Sciencemadness Discussion Board

Synthesis of malonic acid

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Magpie - 17-9-2010 at 10:39

I have recently tried a preparation of calcium malonate using an older procedure by Subramaniam et al, as offered by DJF90. This procedure, as excerpted, is shown below:

"Oxidation of Malic Acid by Hydrogen Peroxide in the Presence of Ammonia.

dl-Malic acid (5 g.) was dissolved in a 20-volume (6%) solution of hydrogen peroxide (100 c.c.), and the liquid was made just alkaline with concentrated aqueous ammonia and diluted to 150 C.C. with water. After 30 hours the reaction mixture was shaken with animal charcoal (5 g.) to remove the undecomposed hydrogen peroxide still present. The solution was filtered, boiled, and treated with an excess of calcium chloride solution. After concentration to 100 C.C. and subsequent standing for 3 days, the white crystalline precipitate (5.25 g.) was collected, washed with water, and dried in a vacuum [Found : Ca, 21.7. Calc. for CH2(CO*O),Ca,2H20: Ca, 22.3%].

A quantity of this calcium salt (1-5 g.) was heated in a sealed tube with glacial acetic acid (5 c.c.) and freshly distilled cinnamaldehyde (30 drops) at 100" for 10 hours. The product was purified as detailed in a previous case and yielded 0.32 g., which melted at 208" (decomp.), alone or mixed with authentic cinnamylidenemalonic acid of m. p. 208" (decomp.) (0.1510 g. required 274 C.C. of NI20-NaOH. Calc., 27.7 c.c.)."

A white precipitate of the stated weight was indeed obtained. However, extraction of the acidified salt with ether did not yield the desired malonic acid.

Although a method for identifying the salt as a malonate is presented in the article, it appears cumbersome. Does anyone have any other suggestions as to how putative Ca malonate can be identified?

experimenter - 25-7-2011 at 09:44

By reacting glycerol with HCl/ZnCl2 (Lucas test) the middle hydroxyl group (OH) could be substituted by Cl. So you get CH2(OH)-CHCl-CH2(OH). From this, substitute the chloride ion with hydrogen (using Zn) in order to obtain 1,3 propanediol. Oxidize this to the malonic acid.

I don't know if this could work. Probably you will see no turbidity in the first reaction because the chlorinated product is water-soluble (because of two hydroxyl groups). Isolation of this product from the unreacted glycerol could be another problem.

Roger86 - 17-8-2011 at 12:59

Quote: Originally posted by Magpie  
Malonate salts are indeed present in the juice of beets. Precipitation of Ca malonate is a problem for industrial refiners of sugar beets. It is present at something around 2% in sugar beets IIRC. It would be an interesting challenge to extract malonate from beets IMO.


If its intresting, then i hope you dont mind in helping me,i decided to do just that

I think that getting calcium malonate from beetroot is an achivement id like to have, has anyone written extraction guide yet, because id like to try, im not expert at chemistry but i have degree as a lab worker and i dont mind trying many times

what i believe i should do first is to make some calculations on economics

in my country beetroot costs 0,9€ per kilogram and if there is 2 % calcium malonate the price of extracted malonate at 0% loss would be 45€ per kilogram witch would be a good price, and i also like doing some cooking:)

Since its economicaly a sound plan im going to start my experiments next monday when i get some money for chemicals

and of course the game plan, witch i hope i can get some feedback on

1.Im going to cut the beetroot to slices and boil them in water for some amount of time, since i have no experience in cooking beetroot i have no idea for how long, but i will do so for as long as it takes to soften them up.Then im going to use blender to break the stuff in to a paste,to help the color dissolve in water.I know from a reliable source that calcium malonate will not dissolve in water.There is no source as to how low the solubility is but what iv read, calcium malonate is 'cheese like precapitate'.im going to save the water and drink it for its vitamins and antioxidants.

2.im going to put fresh water in and put the beetroots from steel cooking pot to plastic bucket and add some acid, i plan to use sulfuric from battery acid.Battery acid should be pretty pure ~30%.Calcium sulfate is going to precapitate at this point.Maybe, i might not see anything because calcium malonate is already insoluble, it might just get replaced by the sulfate.

3.Im going to filter the liquid that i get from that. I should now have pink malonic acid solution.Now this is the part id need theoretical help.Should i now proceed with options;

a)dry this off (pain in the ass) and esterify and distill.

b) use calcium compound to precapitate it and then wash with water

c)put non water miscible solvent like ether and extract with that


As a conclusion,i know that im not going to get pure stuff, its going to be contaminated with the red color and some organics from the vegetable, but i dont really need it to be analytically pure.I dont even have a use for malonic acid yet but i wanted to do some kitchen friendly chemistry for a while.

Has someone already done this, and if can i get link to the quide?if not i'd like to make experiments and reading and write the guide.

Ps.should i use beetroot or sugar beet?

[Edited on 17-8-2011 by Roger86]

Magpie - 17-8-2011 at 14:51

Here's a reference you might want to read:

http://pubs.acs.org/doi/pdf/10.1021/ie50495a018

I have never tried this. I do have in my notes that the industrial juice extraction was done at 70-74C for 100 minutes.

Ether extraction may be the best way to separate the malonic acid from the other water solubles such as amino acids. Other acids may tag along with the malonic acid.

manimal - 21-8-2011 at 17:02

How about the oxidative decarboxylation of aspartic acid with TCCA, followed by hydrolysis of the nitrile?

Synthesis of Malonic acid...

FrankMartin - 21-8-2011 at 21:13

This may be done via enolate (crossed claisen) chemistry, vis:

Etn-Butyrate + DiEthylCarbonate = diethyl ethylmalonate + EtOH

Using NaEthoxide as a reagent.

The "diethyl ethylmalonate" is also known as "Ethyl Malonic Ester"
Presumably simple DiEthylMalonicAcid needs EtAcetate instead of Etn-Butyrate.

This patent gives this and similar examples:
US2367632 And the process is/was called "Carbalkoxylation"

Regards.
Frank

Roger86 - 22-8-2011 at 09:19

As i sayed i started today working towards OTC source of malonates.With attachement is a quide i wrote for myself, please help me to improve it.I got to step 7 today.Tomorrow im going out to the hardware store to buy some impure NaOH and some CaCl2.

But, i cooked the vegetable for 60 minutes, untill it got soft, i didnt have blender so i just let the H2SO4 work for 15 minutes with mixing.

I did some reading and it seems that the colour of the beetroot is dependent on PH.I washed most of the colour from the plant away, but when sulfuric acid was added, the colour became more violet than red.Now i have 1,5dl of beetroot juice with sulfuric acid in it(actually, from this point it smelled like blackcurrants. I plan to make it basic with lye and put CaCl2 to make it precapitate.I read that the violet color turns to yellow at caustic PH.

When i'm done with this quide, is it ok to have link to my guide, or do i just post it here as document? problem is that upload limit is 2MB witch doesnt leave much to get creative with...

And i read Magpie's link, would it be possible to get glutamic acid from it too? because i would love to have some GABA:D

Attachment: Calcium Malonate.rtf (1kB)
This file has been downloaded 815 times

Ebao-lu - 23-8-2011 at 01:15

[edited]

[Edited on 23-8-2011 by Ebao-lu]

bbartlog - 23-8-2011 at 07:31

Quote: Originally posted by Roger86  
I plan to make it basic with lye and put CaCl2 to make it precapitate


Not sure where you got your procedure, but I believe you will precipitate CaSO4 along with your calcium malonate. 2NaOH + H2SO4 -> Na2SO4 + 2H2O, then CaCl2 + Na2SO4 -> 2NaCl + CaSO4 (driven by solubility as the CaSO4 is relatively insoluble). This may not be an insuperable objection if you have some way in mind to separate calcium malonate from calcium sulfate, but in any case don't assume that all that white precipitate is malonate.

Roger86 - 23-8-2011 at 07:40

I dont expect the precapitate to be pure malonate, the process is so that i dont have to evaporate tons of water.I now have a plan to esterify the malonic acid to make diethylmalonate and then distill.

I havent added the calcium chloride yet, so i havent really made the mistake yet:)

But, i could always separate malonic acid from the sulfuric acid by just letting it dry, couldnt i? i suspect its going to be a very long process, but as i stated earlier, im not afraid to do some hard work:cool:

Magpie - 23-8-2011 at 08:38

I went to the library and looked up the article in the scientific journal I cited above. Did you? There is absolutely no mention of malonic acid or malonates in this article. This articles covers the analysis of the contents of juice extract of sugar beets from at least 3 different regions of the US.

I have done a little researching and can find no reference to malonates in beets in scientific journals. Several, however, make reference to malic acid or malates. So, I don't know why Wiki and its clones keep mentioning malonic acid as a constituent of beets.

I think that the separation of a particular organic acid or its salt from beet juice would be difficult. The scientists resorted to several different ion exchange resins to get these acid anion separations.

[Edited on 23-8-2011 by Magpie]

Roger86 - 23-8-2011 at 10:42

I advanced in my work, i got to step 8 :)

Turns out that you get precapitate even without CaCl2, not much but the precapitate would indicate that i have saturated solution of sodium malonate, and i used very dilute acid and base, so i have a lot of the solution.I never learned to make in small amounts.Would i be optimistic to assume that the precapitate is sodium malonate?

I checked that Encylopedia Britannica also states that there is calcium malonate in beetroot

http://www.britannica.com/EBchecked/topic/360443/malonic-aci...

And if both Wikipedia and Encylopedia Britannica say there's some in it, it's worth trying out.

BTW, where did you get the 2% number? If there was 2% it would be in correlation with what i got as what i think is sodium malonate

Also, i read about the acid being unstable, any info on how long i can store it?


Edit. didnt notice you sayed scientific journals, but i trust wiki and Britannica:D

[Edited on 23-8-2011 by Roger86]

Polverone - 23-8-2011 at 11:39

Quote: Originally posted by Magpie  
I went to the library and looked up the article in the scientific journal I cited above. Did you? There is absolutely no mention of malonic acid or malonates in this article. This articles covers the analysis of the contents of juice extract of sugar beets from at least 3 different regions of the US.

I have done a little researching and can find no reference to malonates in beets in scientific journals. Several, however, make reference to malic acid or malates. So, I don't know why Wiki and its clones keep mentioning malonic acid as a constituent of beets.

I think that the separation of a particular organic acid or its salt from beet juice would be difficult. The scientists resorted to several different ion exchange resins to get these acid anion separations.


According to several older references, malonic acid is present in sugar beets. No quantitative information was found in these pre-war publications. Ullmann's says "Malonic acid is found in small amounts in sugar beet and green wheat, being formed by oxidative degradation of malic acid." Malic acid is not that abundant in beets to begin with. I would guess that while malonic acid is technically present in beets, it's futile to attempt preparative extraction.

Magpie - 23-8-2011 at 11:50

Quote: Originally posted by Roger86  

Turns out that you get precapitate even without CaCl2, not much but the precapitate would indicate that i have saturated solution of sodium malonate, and i used very dilute acid and base, so i have a lot of the solution.I never learned to make in small amounts.Would i be optimistic to assume that the precapitate is sodium malonate?


Yes, sodium malonate is soluble to 148g/L according to:

http://www.chemicalbook.com/ChemicalProductProperty_EN_CB870...
Quote: Originally posted by Roger86  

BTW, where did you get the 2% number? If there was 2% it would be in correlation with what i got as what i think is sodium malonate


I can't remember where I got that 2%. It is not in my notes.

querjek - 24-8-2011 at 13:27

I'm not too sure if this pathway would work--what about :
Serine + oxidant -> 1,3-propanedioic acid 2-amine (sorry if the name is off--I'm out of practice!)
1,3-propanedioic acid 2-amine + HNO2 -> the diazo form of the previous product
diazo compound + reductant -> malonate

What I'm mostly unsure about is the diazotization reaction--I know HNO2 can be kinda finicky depending on the constituents of the compounds involved.

[Edited on 24-8-2011 by querjek]

[Edited on 24-8-2011 by querjek]

Roger86 - 26-8-2011 at 05:15

I't doesnt matter if this isnt full succes, i know i probably have a mix of inorganics and some malates in the precapitate, but i like trying things.So if it doesnt succeed, at least i had fun:)

redox - 26-8-2011 at 07:06

Quote: Originally posted by querjek  
I'm not too sure if this pathway would work--what about :
Serine + oxidant -> 1,3-propanedioic acid 2-amine (sorry if the name is off--I'm out of practice!)
1,3-propanedioic acid 2-amine + HNO2 -> the diazo form of the previous product
diazo compound + reductant -> malonate

What I'm mostly unsure about is the diazotization reaction--I know HNO2 can be kinda finicky depending on the constituents of the compounds involved.

[Edited on 24-8-2011 by querjek]

[Edited on 24-8-2011 by querjek]


Maybe I remember wrong, but I thought diazotisation wasn't possible on aliphatic compounds. The resonance in aromatics stabilizes the diazo compound, but aliphatic compounds don't have these stabilizing effects. I think when you diazotise your acid it will release nitrogen immediately and form 2-hydroxymalonic acid.

Here's a ref: http://in.answers.yahoo.com/question/index?qid=2011051821215...

querjek - 26-8-2011 at 13:23

Quote: Originally posted by redox  
Quote: Originally posted by querjek  
I'm not too sure if this pathway would work--what about :
Serine + oxidant -> 1,3-propanedioic acid 2-amine (sorry if the name is off--I'm out of practice!)
1,3-propanedioic acid 2-amine + HNO2 -> the diazo form of the previous product
diazo compound + reductant -> malonate

What I'm mostly unsure about is the diazotization reaction--I know HNO2 can be kinda finicky depending on the constituents of the compounds involved.

[Edited on 24-8-2011 by querjek]

[Edited on 24-8-2011 by querjek]


Maybe I remember wrong, but I thought diazotisation wasn't possible on aliphatic compounds. The resonance in aromatics stabilizes the diazo compound, but aliphatic compounds don't have these stabilizing effects. I think when you diazotise your acid it will release nitrogen immediately and form 2-hydroxymalonic acid.

Here's a ref: http://in.answers.yahoo.com/question/index?qid=2011051821215...

I've heard that before too about aliphatic compounds. However, could the pH of solution be played with in order to provide resonance stability via the two carboxylates?

not_important - 27-8-2011 at 05:47

Alpha-amino acids can be successfully diazotised. See the following discussion from obscure site http://www.sciencemadness.org/talk/viewthread.php?tid=11148


querjek - 27-8-2011 at 10:41

Quote: Originally posted by not_important  
Alpha-amino acids can be successfully diazotised. See the following discussion from obscure site http://www.sciencemadness.org/talk/viewthread.php?tid=11148



Haha. Sorry for not using the search here more effectively and thanks for the link!

Roger86 - 27-8-2011 at 11:16

I really could use data on what malonic acid, sodium malonate and calcium malonate are soluble in, especially if the solvent is non water miscible.I used google and it didnt provide much help.

Magpie - 27-8-2011 at 11:48

http://www.sciencemadness.org/talk/viewthread.php?tid=11698&...

Roger86 - 28-8-2011 at 00:38

Quote: Originally posted by Magpie  
http://www.sciencemadness.org/talk/viewthread.php?tid=11698&...


I cant open the page, it says im not permitted:(

Magpie - 28-8-2011 at 06:29

Quote: Originally posted by Roger86  

I cant open the page, it says im not permitted:(


You will have to request permission from an administrator via U2U.

bbartlog - 29-8-2011 at 12:27

In this case, though, the reference that is provided in the linked-to post is just a page or two from Atherton Seidell's 1919 book on solubilities. You can find it in Google Books even if you don't get access to the Reference forum. You may be disappointed, though, as it only gives data for malonic acid proper and not for the salts; not only that, but it looks like malonic acid is more or less soluble in all of the listed solvents and so there is no real prospect for crashing it out of solution by addition of some other compound.
My CRC handbook suggests that calcium malonate is rather insoluble, though.

Roger86 - 1-9-2011 at 14:33

Quote: Originally posted by Formatik  

By the oxidation of malic acid (Dessaignes, A. 107, 251)


Tried to search for that book on pdf form but couldnt find it, do you have a link?

Not that i have given up on beetroots, but i seriously would like to read that, especially since it's been done on 19th century technology, what should make it simple to do at home

krystaljjang90 - 2-10-2011 at 13:11

hi all..

I'm a chemical engineering student and I need to design malonic acid plant for my plant design subject..
i'll be really grateful if anyone can anyone tell me about the industrial process of malonic acid..

tq...:)

Magpie - 2-10-2011 at 16:14

Quote: Originally posted by krystaljjang90  

i'll be really grateful if anyone can anyone tell me about the industrial process of malonic acid..


Hi krystal,

Have you checked out the Kirk-Othmer Encycopedia of Chemical Technology and Ullman's Encyclopedia of Industrial Chemistry? Most university libraries should have one or both.

[Edited on 3-10-2011 by Magpie]

krystaljjang90 - 2-10-2011 at 22:22

yeah I've checked them n shortlisted 2 processes which are alkaline saponification of cyanoacetic acid and acidic

saponification of chloroacetic acid..i've spent days searching patents and journals but it was not enough..

can you recommend some links or maybe do you know about these processes and the equipments involved??..tq:)




Magpie - 3-10-2011 at 10:26

Quote: Originally posted by krystaljjang90  

can you recommend some links or maybe do you know about these processes and the equipments involved??..tq:)


Sorry, other than the patents I wouldn't know where else to look.

I'm just guessing that malonic acid is being produced today by the usual Indian and Chinese bulk chemical producers. Businesses don't usually publish details on their processes for obvious reasons.

------------------------------------------------------------

Edit: Here's another possibility. Search the archives of these magazines:

Chemical Engineering Progress
Chemical & Engineering News
Chemical Engineering

[Edited on 4-10-2011 by Magpie]

stygian - 28-10-2011 at 20:22

Quote: Originally posted by Sauron  
BTW red P is not mandatory for chlorination of acetic acid, it merely accelerates the rate of the chlorination. Direct chlorination is UV mediated so you need reliable sunlight or preferably a UV reactor. OR chlorinate with CuCl2 (see thread) or N-chlorosuccinimide, both of which monochlorinate the alpha position of carboxylic acids I think. NBS does for sure and bromoacetic acid would work just as well,


May I ask, to which thread do you refer (wrt CuCl2)? I've not been able to find it.

Boffis - 31-10-2012 at 18:50

Once again I find myself reading a long an painful thread with very little useful content. I think we have established there are only really two practical methods to malonic acid for the amateur. The chloroacetic acid + alkali cyanide and the oxidation of malic acid. The first of these suffers from the availability of sodium and potassium cyanide and the second from the fact that the published proceedure are old and often don't appear to work. Other procedures such as the hydrolysis of malononitrile or the oxidation of 1,3 propandiol suffer from the difficult of obtaining the starting material again (if you can get these compounds you can probably buy malonic acid anyway).

I can't add much more to the first technique but the second looks like fertile ground for investigation, malic acid is easily available from home brew suppliers etc and is cheap; there are dozens of easily available oxidizing agents on the high street or the internet.

I am not going to go through my experiments in detail I have attached a copy of my prelimenary experimental findings for anyone who is interested and I have so far only looked at the oxidation and precipitation as calcium malonite. I intend to try the work up of the precipitates in the near future. However, a summary of the work so far is never the less interesting. I tried oxiding dl malic acid with the following reagents:

Sodium dichromate
Sodium hypochlorite
Hydrogen peroxide and tungstate catalyst
sodium chlorate and vanadium pentoxide catalyst

From the attached file you will see that sodium dichromate and hydrogen peroxide did not work for certain as no calcium salt precipitated. The tungstate catalyst was used with hydrogen peroxide because I have somewhere in my documents a reference to Fe salts and H2O2 being used to oxidize malic acid to oxaloacetic acid, though there papers posted on this thread that describe the oxidation of citric acid to malonic acid via several possible intermediates so this route is not closed but clearly requires different conditions.

Sodium chlorate with V2O5 gave only a slight precipitate inspite of the apparently fairly vigorous reaction so once again oxaloacetic acid may be the main product.

It would appear on the basis of the amount of precipitate formed that the sodium hypochlorite method is by far the most successful. However, towards the end of the addition of the hypochlorite the solution became cloudy and heavy mobile droplet formed in the liquid and the whole smelled strongly of chloroform. This suggests that towards the end the conditions become alkaline and the haloform reaction becomes an important side reaction. Experiment with buffering with HCl towards the end were tried to prevent this but there is clearly much scope for improvement. That said the reactants are cheap and easily obtained so modest yields may not be an issue.

Excessive oxidation could theoretically produce oxalic acid which would also precipitate with calcium salts so the formation of a precipitate with calcium chloride does not prove that malonic acid was formed, however, the absence of a precipitate indicates that it was not formed.

One further point is that when using calcium chloride to precipitate free malonic acid hydrochloric acid is liberated potentially dropping the pH to a point where calcium malonate will no longer precipitate. Clearly there is much scope for the optimisation of this method.

The precipitates from the hypochlorite oxidation experiments where subjected to the diphenylamine-sulphuric test for oxalates and gave practically negative results indicating very little calcium oxalate to be present.

Attachment: Malic acid Oxidation Experiments.docx (18kB)
This file has been downloaded 1149 times

[Edited on 1-11-2012 by Boffis]

Boffis - 2-2-2014 at 16:38

I have recently returned to the topic of OTC synthesis of Malonic acid both from the oxidation of malic acid and via cyanoacetic acid. While looking for reasonably recent online papers concerning the former process I came across this one:

Effect of MnII ions on the oxidation of the oxidation of malic and oxaloethanoic acids by aqueous HCrO4-

Zaheer Khan and Kabir-ud-Din, Transition Metal Chemistry, v26, p672-678, 2001

This paper explores the catalytic affect of MnII on this reaction but I could only access the first page, however, on this page there is a claim that following a measurement of the amount of CO2 evolved the reaction must approximate to:

12HCrO4- + 9C4H6O5 + 48H+ ==> 12CrIII + 2C2H4O2(acetic acid) + 7C3H4O4 +11CO2 +39H2O
(14H2O in the paper but this is clearly a typo)

This is a higher ratio of oxidant than I used above but I would still have expected some malonic acid to have been precipitated. I will investigate this further when I get chance.

DoctorZET - 13-4-2014 at 12:43

I know those 2 methods ... and I also tryed the old clasic method (acetic acid --> cyanoacetic acid --> malonic acid) and I observe that it consume a lot of cyanide salts, wich are hard to make (by me), as I'm a home-laboratory-chemist.
But something come into my mind ... there might be a way to obtain malonic acid more easy and in a much more pure form (not using chromates, permanganates, cyanides...)

The process look like this:

CH3-COOH(liquid) + Cl2(gas) --(intense blue light, traces of acetic anhydride and some CCl4, 60-70 *C, probably on an ethanol bath)--> Cl-CH2-COOH + HCl

HCOOH(gas) + Cl-CH2-COOH (gas) --(traces of H2O and AlCl3 cristals deposited in a glass tube at 190-200*C)--> HOOC-CH2-COOH + HCl

It is corect ? ... I hope it is, because I will test this theory :)


[Edited on 13-4-2014 by DoctorZET]

DoctorZET - 13-4-2014 at 13:08

As soon I post that, I can see a big problem : the malonic acid starts to decarboxylate at about 70*C forming acetic acid ... sooo...at about 190*C should be already decomposed into CO2 and acetic acid. :(
So if I want to do the Friedel-Kraft alkylation reaction in the gas phase (because I want to have a fast reaction), I must do it at a lower pressure.
But I also could do it at max.60-70*C for a few hours, with a lot of AlCl3(better use FeCl3) added and excess of formic acid...
Then I can distill the excess of formic acid.
Sounds good...

An easier way to make malonic acid?

Assured Fish - 2-10-2016 at 22:16

I read the entire thread and as far as i can tell nobody suggested this but correct me if im wrong.
Simply react allyl alcohol with a hydrogen halide or possibly a halide and aluminium to get allyl halide (1-halo-2-Propene) then after drying it thoroughly react with magnesium in diethyl ether or THF to get the grignard reagent then of coarse either add dry ice or bubble CO2 through the grignard reagent to get 3-buteneoic acid after acidification with H2SO4, then obviously reflux with potassium dichromate or permangenate and neutralize then distil and bobs your uncle your done.

CH2CHCH3-MgBr + CO2 ------> CH2CHCH3COOH

CH2CHCH3COOH + K2Cr2O7 ------> COOHCH2COOH

Allyl alcohol can easily be synthesized OTC from oxalic acid and glycerol, the only annoying part that i can see about this method would be drying the allyl halide but i mean fractional distillation over a dessicant such as calcium chloride or hell even molecular sieves then maybe left to dry over some sodium overnight not really that difficult.
Also given that butanoic acid has a boiling point of 164*C i would speculate that buntenoic acid would have a similar boiling point thus making pretty much all the workups piss easy.
I just dont get why nobody else thought of this.

wg48 - 3-10-2016 at 01:08

Allyl alcohol synthesized from oxalic acid and glycerol ???
How the heck can that happen, you would have to be mad to think that was possible were my first thoughts LOL

Well I checked apparently it is correct but the yield is low. I am still looking for the detailed mechanism.

Ok a little off topic and its probably been posted already:

https://erowid.org/archive/rhodium/chemistry/allylalcohol.ht...

"Experimental

Allyl Alcohol from Glycerol and Oxalic Acid
A mixture of 500g anhydrous oxalic acid and 500g of glycerol was heated in a partial vacuum on a water bath for 4-5h (or longer) until formic acid ceased to distill over. The mixture was then gradually heated to 240°C under ordinary pressure, the flask being fitted with a fractionating column. At 220-225°C, CO2 was given off and a mixture of approximately equal amounts of allyl alcohol and allyl formate distilled over leaving in the distillation flask a residue containing somewhat 50% of the glycerol originally used. Practically no acrolein was produced. The distillate was treated with 50g NaOH in 1000ml water (to hydrolyze the formate), allowed to stand for 12h at room temp, and finally distilled. The first 300 ml of distillate contained all the allyl alcohol, which after fractionation yielded 200-210g of a allyl alcohol/water mixture (bp 87-88°C) which may be dehydrated using anhydrous potassium carbonate yielding approximately 150g of anhydrous allyl alcohol."

[Edited on 3-10-2016 by wg48]

Assured Fish - 4-10-2016 at 12:11

The triethylorthoformate method posted here looks like a better way to go about allyl alcohol preparation, the thread also goes into more detail regarding the oxalic acid glycerol method although the mechanism still seems obscure. I do rest my case however that allyl alcohol should be fairly straightforward and OTC to prepare and then the grignard carbonation and oxidation of the double bond to finish up.

http://www.sciencemadness.org/talk/viewthread.php?tid=6274

wg48 - 4-10-2016 at 13:58

Quote: Originally posted by Assured Fish  
The triethylorthoformate method posted here looks like a better way to go about allyl alcohol preparation, the thread also goes into more detail regarding the oxalic acid glycerol method although the mechanism still seems obscure. I do rest my case however that allyl alcohol should be fairly straightforward and OTC to prepare and then the grignard carbonation and oxidation of the double bond to finish up.

http://www.sciencemadness.org/talk/viewthread.php?tid=6274


Well triethyl orthoformate route to allyl alcohol may be cleaner and more productive but it looks a long way from OTC.

Darkstar - 5-10-2016 at 00:37

Quote: Originally posted by wg48  
I am still looking for the detailed mechanism.

Quote: Originally posted by Assured Fish  
the thread also goes into more detail regarding the oxalic acid glycerol method although the mechanism still seems obscure.


As far as I'm aware, the exact mechanism for the reaction isn't actually known; however, if you're having trouble trying to come up with a way to get from oxalic acid and glycerol to allyl alcohol (it's a little tricky), I've drawn a plausible mechanism that is actually based on some recent literature where deuterium labeling was used:

mechy.png - 255kB

The oxalic acid and glycerol initially react to give a mono-oxalate ester that, upon ring closure, gives 2-hydroxy-4-(hydroxymethyl)-1,3-dioxolan-2-carboxylic acid. This unstable dioxolane ring system then undergoes thermal decarboxylation to the more stable 4-(hydroxymethyl)-1,3-dioxolan-2-ol, which is in equilibrium with both glycerol mono-formate isomers as well as their hydrolysis products, glycerol and formic acid:

equilibrium.png - 77kB

The dioxolane form of glycerol mono-formate then reacts with some of the formic acid produced by the hydrolysis shown above to give a resonance-stabilized carbocation, which gets attacked by the resulting formate ion to give 4-(hydroxymethyl)-1,3-dioxolan-2-formate. The formate ester undergoes a final thermal decarboxylation reaction to give both the desired allyl alcohol as well as give back the formic acid that was consumed.

Additionally, it's also possible that, instead of attacking the electrophilic carbon, the formate ion instead abstracts the acidic proton to give an unstable carbene that immediately decomposes into carbon dioxide and allyl alcohol:

mechy2.png - 100kB

UC235 - 8-10-2016 at 00:59

http://www.sciencemadness.org/talk/viewthread.php?tid=13122

There are now a few sources of 1,3-propanediol available as a cosmetic ingredient.

Pumukli - 8-10-2016 at 12:03

And also available as antifreeze for solar systems. (At least in the EU.) Not as cheap as ethylene-glycol or 1,2-propane-diol and not so common in every hardware store, but for a 10 or 20 liters can the price is not bad.
(The reason is reportedly 1,3-propane-diol whitstands better the 150+ Celsius range encountered in solar systems than other diols.)

mr.crow - 9-10-2016 at 08:27

Perhaps treating amino acids with TCCA or NaOCl would yield malonic acid.

https://www.sciencemadness.org/whisper/viewthread.php?tid=32...

https://www.sciencemadness.org/whisper/viewthread.php?tid=29...

It looks like the mono-chloroamine of aspartic acid will decompose into an aldehyde and dichloroamine will produce the nitrile.


[Edited on 9-10-2016 by mr.crow]

clearly_not_atara - 13-10-2016 at 13:02

I had a somewhat long synthesis in mind from aspirin, ethyl bromide, sodium ethoxide, and hydrogen peroxide:

acetylsalicylic acid + NaOEt + EtOH + ∆ >> sodium acetylsalicylate + EtOH (g) i.e. just make the sodium salt alkoxide is used here or use something else

sodium acetylsalicylate + EtBr >> NaBr + ethyl acetylsalicylate

ethyl acetylsalicylate + NaOEt (dry) >> 4-hydroxycoumarin (2,4-dioxodihydrobenzopyran) [1]

4-hydroxy-2-chromone + NaOH + H2O + H2O2 >> sodium 2-hydroxyphenyl-1-oxopropanoate (aq)[2] + H2O2 >> catechol + malonic acid [3]

[1] http://www.orgsyn.org/demo.aspx?prep=cv1p0235 (see Discussion; the extension from intermolecular to intramolecular is sort of a leap but usually makes things easier anyway)

[2] http://www.sciencedirect.com/science/article/pii/S1386142506...

[3] http://orgsyn.org/demo.aspx?prep=CV1P0149 (it is an o-hydroxyketone at the end of the day)

-------

Also, the Baeyer-Villiger oxidation of levulinic acid gives 3-acetoxypropanoic acid. Levulinic acid in turn is produced from sucrose and HCl.

-------


EDIT 2:

Maybe you could make 1,3-dinitropropane by the Michael addition of nitromethane to niroethylene? Nitroethylene then is made from nitromethane and formaldehyde!

Reduction with a variety of reagents (CrCl2 reportedly gives oximes IIRC) gives malondialdehyde dioxime, a precursor to malonic acid as well as many other interesting compounds, including malononitrile.

-------

EDIT 3: last one i swear

ethyl chloroacetate + zinc + formaldehyde >> ethyl hydracrylate aka ethyl 3-hydroxypropanoate

(reformatsky reaction)

NB: with acetaldehyde this gives an ethoxide-free preparation of ethyl acetoacetate by oxidation

[Edited on 13-10-2016 by clearly_not_atara]

[Edited on 13-10-2016 by clearly_not_atara]

[Edited on 13-10-2016 by clearly_not_atara]

Boffis - 1-10-2017 at 15:37

I was recently going through a dark corner of my lab when I found 4 samples of calcium salts prepared by the alkaline oxidation of malic acid in the hope of producing malonic acid as described above. I decided to finally complete this work by analysing these precipitates. I decided to proceed by adding just enough sulphuric acid to liberate the organic acid but since I didn't know exactly what compound I had and therefore how much acid it would require I first had to analyse the Ca content. I did this by taking a small sub sample of about 0.2g accurately weighed out and calcining it in a pre-weighed nickel crucible. The calcine was cooled and left in in a plastic box over ammonium carbonate for a few days to ensure conversion of any calcium oxide to carbonate. The calcines were reheated to just 120 degrees in an oven to drive off any water and ammonia and then weighed. The weight of CaCO3 remaining was then used to calculate the amount of sulphuric acid required. The weights seem rather higher than I had been expecting since I had assumed that the precipitate consisted of a mixture of calcium malate, malonate 4 hydrate and oxalate dihydrate. The CaCO3 weights suggested that they were anhydrous and even then there was too much calcium present. For one sample I dissolved to check the calcine by dissolving it in a little dilute HCl, then diluting it to 250ml and titrating it as though it was hard water using a buffer, solochrome black as indicator and standard EDTA solution (bought). This procedure confirmed that the calcine was essentially pure CaCO3.

One of the samples was too small to be worth treating but the other three were then reacted with the appropriate amount of 1M sulphuric acid which resulted in copious evolution of a colourless odorless gas, certainly CO2. The slurry was warmed a little to ensure complete reaction and then chilled overnight to allow the calcium sulphate to cystallise then evaporate down on a water bath in a shallow ceramic bowl to a thick solution and left to crystallise. Only further calcium sulphate was recovered. No evidence of organic acids could be found in the residues, not even acetic acid from the breakdown of malonic acid.

From this I conclude that the alkaline oxidation of Malic acid (more correctly malate salts) results not in malonic or even oxalic acid but instead carbonate ions, chloroform and only organic acids that form soluble calcium salts such as formate or acetate. The method therefore is a complete failure.

Just thought you ought to know! Back to the drawing board.

clearly_not_atara - 3-10-2017 at 09:29

There's a prep of 2-methylmalonic acid on Orgsyn which proceeds via 3-methyl-2-oxosuccinic acid. Apparently the ester of this is pyrolysed and undergoes some kind of carbonyl-elimination rearrangement.

Starting from diethyl malate, oxidation with an anhydrous CrO3 synthon (such as PCC or something) should give oxaloacetic acid -- be aware that alpha-ketoesters hydrolyse easily. Pyrolysis of this ester may, if the analogy holds, generate diethyl malonate.

I think it's worth a try, at least. There's also the possibility of somehow reducing alloxan to barbituric acid.

Claisen condensation

Niter of Potash - 15-10-2017 at 02:30

My idea is to make malonic acid by mixed claisen condensation between ethyl formate and ethyl acetate.

That /product/ (i'm not good at naming compounds) would be ester on one side, and aldehyde on another. Oxidizing that aldehyde with HNO3, KMnO4 or something silimar, sould yield monoester of malonic acid, or pure acid, if ester gets hydrolised.

Since I can't really get or make pure Na metal (I tried NurdRage's dioxane method, but since my stirrer is broken, I couldnt extract decent quantaty of Na metal), I would probbaly use Na/MgO aggregate, mix that with dry EtOH, and filter, to get sodium ethoxide solution, and use that in reaction.

Sadly, I'm pretty buisy so I can't try this out, but can anyone confirm that it would work at all, or why not?

EDIT:

As soon as I posted reply, I relalised what could go wrong.

http://www.prepchem.com/synthesis-of-benzyl-benzoate/

Reactions similar to this could accure, and that would yield malonic acid - 3-hydroxypropionic acid ester.

That,however, is not a huge issue, as 3-hydroxypropionic acid could be further oxidised to form malonic acid.

Not a big deal, I guess, and this would only make extraction and purification steps a bit more complex

[Edited on 15-10-2017 by Niter of Potash]

Boffis - 18-10-2017 at 10:52

Will diethyl carbonate undergo a cross claisen condenstion with ethyl acetate to give diethyl malonate directly? Or is this just wishful thinking?

:)

clearly_not_atara - 18-10-2017 at 10:59

In order to achieve the desired selectivity I would think you want to use diMethyl carbonate and tert-butyl acetate, although isopropyl acetate is similar and much more OTC.

I think it's possible... yields may be complicated by the formation of acetoacetate.

AvBaeyer - 18-10-2017 at 12:51

Most of what is being proposed here is too far fetched for the typical hobby or home lab. Why not just buy diethyl malonate which is cheaply available from perfume chemical suppliers. It is essentially OTC. The diester can serve as the basis for lots of chemistry including the preparation of the the half-ester and malonic acid itself.

I realize folks like to speculate on all sorts of possible chemical reactions, but most of the time it's just easier to buy what you need. Do not mean to offend, just my thoughts.

AvB

Boffis - 18-10-2017 at 23:34

Quote: Originally posted by AvBaeyer  
Most of what is being proposed here is too far fetched for the typical hobby or home lab. Why not just buy diethyl malonate which is cheaply available from perfume chemical suppliers. It is essentially OTC. The diester can serve as the basis for lots of chemistry including the preparation of the the half-ester and malonic acid itself.

I realize folks like to speculate on all sorts of possible chemical reactions, but most of the time it's just easier to buy what you need. Do not mean to offend, just my thoughts.

AvB


Agreed but we can dream.. :)

DraconicAcid - 19-10-2017 at 10:25

And here I was wondering if it was possible to easily make esters out of malonic acid....

Niter of Potash - 29-10-2017 at 06:04

What about allyl alcohol/acrylic acid route?
Allyl alcohol is not hard to make, just pretty nasty :(

In theory, you could do anti-markovnikov addition of HBr to acrylic acid, hydrolise 3-bromopropionic acid, and then oxidise 3-hydroxypriopinic acid to form malonic acid.

Also, what would happen if you try to oxidise that double bond with KMnO4 or nitric acid, for example?

Would you end up with malonic acid, epoxide, or that double bound gets cleaved with final products being oxalic and formic acid?

[Edited on 29-10-2017 by Niter of Potash]

clearly_not_atara - 29-10-2017 at 19:20

AvBaeyer: if everyone could buy diethyl malonate this thread might not be here.


However I believe I have a route using only sulfuric acid, malic acid, copper sulfate, and magnesium acetate. I have noticed that magnesium malonate appears to be significantly less soluble than the sulfate:
Quote:
A. Magnesium Malonate: 180.6 g of magnesium acetate tetrahydrate (Mg(OAc)2.4H2O) was dissolved in 500 ml deionized water. Separately, 89.4 g malonic acid (C3O4H4) was dissolved in 60 ml deionized water. The solutions were mixed, bringing about immediate precipitation of Mg(C3O4H2)3.nH2O. After filtering and washing, the yield was 136 g.
https://www.google.com/patents/US6193904

This allows malonic acid to be separated from solutions containing sulfuric acid by the action of magnesium acetate.
In particular, some references indicate that malic acid is converted to formylacetic acid by the action of concentrated sulfuric acid.
https://books.google.com/books?id=mnsKyupepQEC&pg=PA125&...
It's possible that the oxidation with nitric acid depends on formylacetic acid as an intermediate. Nitric acid is known to oxidize aldehydes.
This suggests that malic acid oxidation could also occur in concentrated sulfuric acid containing anhydrous copper (II) sulfate, since Cu2+ oxidizes aldehydes as well. The reaction can then be quenched with magnesium acetate. Copper sulfate has the advantage of producing no gaseous byproducts; copper is filtered from the rxn mixture or reoxidized by dioxygen. Malonic acid can probably be recovered from the magnesium salt by the action of oxalic acid, since magnesium oxalate is highly insoluble and oxalic acid is much stronger than malonic acid. If oxalic acid is unavailable, phosphoric acid might work.
The instability of malonic acid is annoying however so it might be more reasonable to perform a double displacement on magnesium malonate by treating it with hot sodium carbonate solution; IIRC the malonate ion has a much longer lifetime in solution than the free acid (I know this is true of acetoacetic acid). Malonic diesters can then be prepared directly from sodium malonate by alkylation with alkyl halides.

[Edited on 30-10-2017 by clearly_not_atara]

Magpie - 29-10-2017 at 20:07

In the US diethyl malonate is easily purchased from perfume suppliers as stated by UC235.

In Prepublication I have posted a synthesis using 1,3 propandiol. A few years ago this was more difficult to get. Now it is readily available from cosmetic suppliers and Amazon, as previously mentioned. Are these sources not available to you?

Niter of Potash - 30-10-2017 at 12:05

I just found this document online.

Seems like that malonic acid can me made by oxidation of malic acid by sodium hypochloride, in somewhat acceptable yield.

Sadly, HNO3 was not tested in this article as oxidising agent, and NaClO used was industrial strenght (I can only get 5% hypochlorite :( )

I guess I will just have to buy malic acid and try HNO3 oxidation myself.

Any ideas why dichromate and H2O2 methods don't work?


Attachment: Malic acid Oxidation Experiments.docx (18kB)
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Niter of Potash - 30-10-2017 at 12:40

Quote: Originally posted by Magpie  
In the US diethyl malonate is easily purchased from perfume suppliers as stated by UC235.

In Prepublication I have posted a synthesis using 1,3 propandiol. A few years ago this was more difficult to get. Now it is readily available from cosmetic suppliers and Amazon, as previously mentioned. Are these sources not available to you?


So far, I wasn't able to find 1,3PD locally, and i'm a bit too paranoid to order it online, outside my country.

Oh well, I spent months trying to distill toluene from various nitro thinners, and pretty much failed every time(I couldn't purify it to desired purity), just to find out that all this time, one specific, very cheap paint thinner was 100% toluene...so yeah, maybe 1,3PD is just in front of my nose all this time as well.

Magpie - 30-10-2017 at 14:10

1, 3 propanediol is an ingredient for making cosmetics at home and is available at
Somerset Cosmetics. I think your paranoia meter is unnecessarily pegged.

[Edited on 30-10-2017 by Magpie]

[Edited on 31-10-2017 by Magpie]

Niter of Potash - 27-12-2017 at 17:20

So I took a look at Magpie's malonic acid synthesis (this one:)

http://www.sciencemadness.org/talk/viewthread.php?tid=13122

Is there any reason why 6M nitric acid was used?
What would happen if you used something like 30%,40%, or even higher percentage nitric acid?
Are there any drawback (malonic acid decomposing,for example), except maybe having harder time controlling reaction?

Benefits would be less water to evaporate after synthesis.

Magpie - 27-12-2017 at 20:13

You can easily get a dangerous runaway reaction if the nitric is too strong or added too fast.

Jackson - 22-2-2019 at 08:44

I know this thread is kinda old, but I think its going to be better to ask a question on an existing thread, rather than start a new thread. I know that tartaric acid can be oxidized by nitric acid to tartronic acid, which is also known as 2-Hydroxymalonic acid. My question is, can this be dehydrated to Malonic acid? I don’t think it would, but seeing as tartaric acid, or at least Pottasium hydrogen tartrate is readily available, it would be very accessible to most people.

Tsjerk - 22-2-2019 at 08:59

Of course synthesizing is fun, but this might be easier (I never worked with them, but it came up on the first page of Google).

http://www.thegoodscentscompany.com/data/rw1004331.html

clearly_not_atara - 22-2-2019 at 11:31

Jackson: no, I don't think that's a realistic possibility. Maybe it could be reduced by Pd/H2 in acid conditions, but that is literally a wild guess and not worth wasting palladium on. Plus the very similar oxidation of malic acid with nitric acid turns out to be touchy.

Perhaps some other oxidation of malic acid could work. For example, bromine water is known to convert hydroxyacids to carbonyls and H2O2 oxidizes aldehydes to acids, so maybe NaBr/H2O2 would work. However, overoxidation of malonic acid is possible.

Mush - 7-5-2020 at 16:06

potassium dichromate, water
Dessaignes; Justus Liebigs Annalen der Chemie; vol. 107; (1858); p. 251

ammonium hydroxide, dihydrogen peroxide, T= 20 °C
Subramaniam; Stent; Walker; Journal of the Chemical Society; (1929); p. 2490

silver(l) oxide
Behrend; Dreyer; Justus Liebigs Annalen der Chemie; vol. 416; (1918); p. 219

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beebeautiful.org.uk used to have Cherry Fragrance Oil containing 25-50 diethyl malonate

https://beebeautiful.org.uk/shop/wp-content/uploads/2014/06/...

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[Edited on 8-5-2020 by Mush]

clearly_not_atara - 8-5-2020 at 09:56

Oxidative degradation of linoleic acid with KMnO4 or H2O2/WO3 ought to generate malonic acid actually. This is extremely OTC and easy although the atom efficiency is dismal.

Extracting malonic acid from the other products -- hexanoic acid and azelaic acid -- you can probably take advantage of different solubilities in neutral water: hexanoic 1% w/w, azelaic 0.2% w/w, malonic 76% w/w.

[Edited on 8-5-2020 by clearly_not_atara]

kmno4 - 9-2-2021 at 04:23

During searching something via Google, I came across an article:
The Abiotic Oxidation of Organic Acids to Malonate
It is rather fresh (end of 2016) and seems not to be posted on the board.
It is about Fenton-like oxidation of several organic acids, including malic and citric ones. The article is, however, too optimistic.
There are many acid by-produscts of the reactions and it may be difficult to extract malonic acid directly form these post-reaction mixtures.
Possibly, converting all acids into its methyl esters, would give better way of separation.
Anyway, the article is short and the oxidations are very cheap, at least in theory :P

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Boffis - 9-2-2021 at 06:37

Interesting. Many years ago I did a lot of similar work oxidizing particularly malic acid with H2O2 and various catalysts and then precipitating the malonic acid as its Ca salt I reported th work on SM. The Ca salt was isolated and the free acid liberated with a calculated quantity of sulphuric acid. Under mildly acid conditions only oxalic acid should interfere. In the end oxalic acid was all I got!! Malonic acid and oxalic acid are easily separated by fractional crystallisation, oxalic acid crystallises first. My conclusion was that under neutral or mildly acid conditions (free malic acid) it was hard to stop the oxidation at malonic acid and oxalate and unreacted malic acid result. Under alkaline conditions carbonate is the main product.

I look at this paper again but it appears to be a bit light on actual experimental detail but it may be worth another bash.

Fery - 9-2-2021 at 09:50

I love these beautiful ideas you have guys and pioneering experiments you did / are doing / will be doing to bring this interesting acid to hobbyists. Who does not want to see Belousov - Zhabotinsky reaction with one's own eyes?
Due to my laziness I've bought this acid very cheaply from https://chemcraft.su/product/24482 and diethylmalonate (beautiful apple scent) from an ebay seller from USA. I saw malonic acid also at s3 chemicals https://shop.es-drei.de/komplexchemie/8766/malonsaeure-min.-... just somewhat more expensive, but they sell to individuals too.

clearly_not_atara - 9-2-2021 at 09:54

I wonder if you could remove most of the oxalic acid from the solution by precipitating potassium tetraoxalate? As far as I know, there are no insoluble salts of potassium and malonate at any stage of protonation, but the solubility of KH3(C2O4)2 is very low, about 2.5% w/w in distilled water and probably lower at its equilibrium pH ~1.5.

Probably no good if there's no actual malonate produced, but if you're getting mostly oxalate and a little malonate, being able to isolate the yield would be something. The ammonia/H2O2 method linked by Mush yields around 20%.

kmno4 - 9-2-2021 at 22:55

Quote: Originally posted by Fery  
Who does not want to see Belousov - Zhabotinsky reaction with one's own eyes?
Due to my laziness I've bought this acid very cheaply from ....

As it is known, the Belousov - Zhabotinsky reaction works with many other reductors, for example citric acid, only (any soluble) bromate is important component.
Alibaba offers malonic acid in prices around several $'s / 1 kg if you order amount > 10 kg.
Unfortunately, shippment from China is very expensive (at least to central Europe). But I am going to order it anyway, I am lazy too :D. This acid and its esters are EXTREMELY useful in OS.
I also like the smell of the esters.

Boffis, I have read about your experiments. In general, oxalic acid is end product of oxidation of many, many organic compounds. That is why I prepared my malonic acid by standard procedure (chloroacetic + cyanide). But without continuous extraction with ether, its separation it is real pain in the ass. Also same malonic acid and its solutions decompose above ~90 C or so. This is not good compound for preparation :(

One more important thing about the article I posted.
It still looks too good for me, but it may work because of not so obvious reasons.
See this article:
DISODIUM PHOSPHATE AS A CATALYST FOR THE QUANTITATIVE OXIDATION OF GLUCOSE TO CARBON DIOXIDE WITH HYDROGEN PEROXIDE.
(in attachment)

So, their "phosphate buffer" may act not only as a buffer, but also as true catalyst.


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[Edited on 10-2-2021 by kmno4]

student - 17-5-2021 at 09:08

Quote: Originally posted by clearly_not_atara  
Oxidative degradation of linoleic acid with KMnO4 or H2O2/WO3 ought to generate malonic acid actually. This is extremely OTC and easy although the atom efficiency is dismal.

I came up with this idea independently, and you mostly stole my thunder. Having recently thought about what could be made using ozonolysis, I realized that acids like linoleic acid have double bonds separated by a methylene group, so that ozonolysis, with an oxidative work-up, would yield one mole of malonic acid per methylene group.

Linoleic acid isn't the best precursor for this because it has only one isolated methylene per molecule. But checking a list of omega 3 fatty acids, there can be up to six isolated methylenes in natural fatty acids. I couldn't find a good source of a fatty acid with six methylenes - DHA is a major constituent of fish oil, but it isn't a majority of the oil and pure DHA isn't economical.

However, a-linolenic acid has three isolated methylenes, and that fatty acid is 55% of the content of flax oil (which also contains 15% linoleic acid), available by the liter. While looking into this I learned that, although flax oil is also called linseed oil, and linseed oil is available at hardware stores, the hardware store stuff, typically called "boiled" linseed oil, has been processed to conjugate the double bonds, rendering it useless for our purpose. The flax oil needed is the food grade oil kept in the refrigerated section of health food stores.

If this approach works, it could allow an inexpensive (once set up), accessible and cost-effective approach to producing malonic acid. Another possible approach would be elimination of the secondary alcohol group of glycerine to give 3-hydroxypropanal, followed by oxidation.

However, while the opportunity lasts, I would prefer to buy malonic acid from a vendor like chemcraft, or even the diester off ebay.

[Edited on 17-5-2021 by student]

Fery - 17-5-2021 at 11:59

Hi student and welcome here. It is nice to obtain the desired product by own synthesis for the beauty of the chemistry.
Recently I've bought 1 L of diethylmalonate for 46 EUR from s3 chemicals (Germany).
https://shop.es-drei.de/ester/695/malonsaeurediethylester-mi...
More time ago I've bought 2 x 500 ml bottles from the ebay seller you linked. I'm very satisfied with both sellers.

Malonic acid from acrolein via hydracrolein?

SplendidAcylation - 25-10-2022 at 02:30

Like many, I have been interested in the synthesis of malonic acid for some time, but I have been foiled by the apparent necessity of cyanides.

I have tried my best to UTFSE and I've read the threads about malonic acid on here, specifically this one, and while there were a lot of very interesting ideas, none of them seemed very likely to be practical or to work.

On page 7 of the above thread, it was suggested "Another possible approach would be elimination of the secondary alcohol group of glycerine to give 3-hydroxypropanal, followed by oxidation."...


Anyway, I was looking at the Wiki page for 1,3-propanediol, and I was surprised to read "1,3-Propanediol is mainly produced by the hydration of acrolein."

I wouldn't have considered this in the first place, based on the assumption that hydration of the above unsaturated aldehyde would follow Markovnikov's rule and end up with the hydroxy in the alpha position, on the 2 carbon, but no! It ends up in the beta position, on the 3 carbon.

I don't know exactly why this is, but I'm guessing that, if the mechanism involves a carbocation intermediate, then it is obvious why this would happen, because the formyl (aldehyde) group is electron-withdrawing, so this would have the secondary carbocation less stable and the primary one more stable, the opposite to addition to an alkene where the secondary carbocation is more stable due to the alkyl electron-donating group.


So, having discovered that hydration of acrolein (and, of course, reduction!) can possibly yield 1,3-propanediol, which could of course be readily oxidised to malonic acid, I did a bit more searching, and came to a few conclusions:



The latter would also work, as Wiki says "3-Hydroxypropionic acid can be obtained by base-induced hydration of acrylic acid", so again, another way to add the hydroxy to the beta position!


Anyway, oxidation of acrolein to acrylic acid doesn't seem to be too straightforward, so the hydracrolein approach seems more interesting.

I found this paper: Hydration of Unsaturated Compounds. XI. Acrolein and Acrylic Acid
I have attached it as a PDF.

Within this paper, there is a reference to an earlier paper, this one:
Dissociationsvorgänge in der Glycol-Glycerinreihe
Also attached as PDF.

It is in German, which I cannot read, but I can infer, thanks to Google Translate, that it says that a solution of acrolein should be heated in a sealed tube for a number of hours, whereupon the water and unreacted acrolein are distilled off, and the hydracrolein is vacuum-distilled, whereupon it solidifies upon cooling.

Seems easy, but it doesn't mention yield, and of course, acrolein is pure evil.


If it were successful to make hydracrolein this way, it would presumably (but not necessarily) be easy to oxidise it to malonic acid, perhaps sodium hypochlorite could be used as the oxidiser, whereupon the solution could be acidified to remove any carbonate and hydroxide ions, and a soluble calcium or magnesium salt added to precipitate the malonic acid as an insoluble malonate salt.

[Edited on 25-10-2022 by SplendidAcylation]

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andyloris - 25-10-2022 at 04:14

Just got a random idea while looking at the strecker degradation wikipedia page:
Could serine undergo strecker degradation to form 3-hydroxypropanal and then be oxidised to malonic acid ?

Texium - 25-10-2022 at 05:52

Nope. Not enough carbons. You’d end up with glycolaldehyde.

andyloris - 25-10-2022 at 06:09

Then could this work with aspartic acid ?

Boffis - 25-10-2022 at 10:28

Since acrolein preparation is no joke and yields are not great in laboratory scale procedures as much tar is produced too, is making malonic acid via acrolein (which I assume you are looking at because it can be prepared from easily available glycerine and sodium bisulphate) really an amateur friendly route?

As andyloris points out there are several well explored routes from aspartic acid and also through beta-alanine. Both of which are cheap and degraded through well studied wet chemistry.

Also what's wrong with the route through 1,3-propandiol as this compound is now easily available online through hobbyist cosmetic ingredient suppliers, particularly in the US but they posted it to me in the UK without problem.

andyloris - 25-10-2022 at 10:46

What is the route from beta-alanine ?

Texium - 25-10-2022 at 11:05

Perhaps you could try using a search engine instead of asking so many one-lined questions in rapid succession.

andyloris - 25-10-2022 at 11:30

I searched on google but I only could find a source saying
Quote:

beta-Alanine can undergo a transamination reaction with pyruvate to form malonate-semialdehyde and L-alanine. The malonate semialdehyde can then be converted into malonate

However I thought a transamination reaction was the swaping of a ketone of a keto acid and the amine of an alpha-amino acid to form a new amino acid and a new keto acid. However beta-alanine is a beta amino acid, and this didn't make sense.

[Edited on 25-10-2022 by andyloris]

Boffis - 25-10-2022 at 12:07

Hi andyloris, give me a few days and I will track down the various references but I seem to recall that hypochlorite ions or their proxies such as the chlorimines like TCCA and NaDCCA convert b-alanine to hemialdehydo-malonate ion. I have several papers at home on these lines.

SplendidAcylation - 26-10-2022 at 02:29

Quote: Originally posted by andyloris  
Just got a random idea while looking at the strecker degradation wikipedia page:
Could serine undergo strecker degradation to form 3-hydroxypropanal and then be oxidised to malonic acid ?


I looked at this and I thought the number of carbons was right too :P
So easy to miscount.
Quote:

Since acrolein preparation is no joke and yields are not great in laboratory scale procedures as much tar is produced too, is making malonic acid via acrolein (which I assume you are looking at because it can be prepared from easily available glycerine and sodium bisulphate) really an amateur friendly route? As andyloris points out there are several well explored routes from aspartic acid and also through beta-alanine. Both of which are cheap and degraded through well studied wet chemistry. Also what's wrong with the route through 1,3-propandiol as this compound is now easily available online through hobbyist cosmetic ingredient suppliers, particularly in the US but they posted it to me in the UK without problem.


Yes, my primary motivation was based on the easy synthesis of acrolein from glycerol.
That's interesting, I wasn't aware of these routes, are they theoretical or are they suspected to work?

Indeed, there isn't anything particularly pleasant about acrolein, but, having read all of the threads I could find here regarding malonic acid, I couldn't see any practical routes avoiding cyanide; Even the oxidation of malic acid seems to be fruitless.

I would be much happier handling cyanides than acrolein, that's for sure, but cyanides are not easy to come by, and if I were to acquire some, I doubt I'd waste them on the synthesis of malonic acid, as you say, 1,3-propanediol is probably the most feasible route.

There has been much talk about the synthesis of cyanides using chloroform and ammonia, but very few positive results, so it seems quite unlikely to be successful.

I shall await your references! :)

andyloris - 26-10-2022 at 04:48

The route from aspartic acid is a random idea I got, but I see no reason why it wouldn't work.

kmno4 - 26-10-2022 at 13:59



..... that is why some time ago I decided to order malonic acid directly from a manufacturer (PRC). Unfortunately, shipping costs almost doubled total price, giving ~40 $ per 1 kg of malonic acid in the end.
Earlier I made this acid by standard method (chloroacetic + cyanide), but without ether continuous extraction apparatus, preparing the free acid is highly problematic. Besides, using K/Na cyanide for this purpose is a waste. There are many better ways to utilize the cyanide ;)
Currently, malonic acid is cheaply (let us say ...) prepared in industry by fermentation methods.

Boffis - 28-10-2022 at 10:58

While I agree that malonic acid is one of those simple organic building blocks that is best bought I can't help but feel that the challenge has a certain attraction for masochists :).

So a few days ago I decided to try a route from beta alanine. First I tried just dissolving 10g of beta alanine in a molar equivalent fairly strong sodium nitrite solution (7.75g in 50ml of water) and then gently warmed it. When the temperature reached about 60-70 C a slow evolution of nitrogen began but it was very slow so I added a molar equivalence of 50% nitric acid fairly quickly. The rate was chosen so that the gas remained colourless (hopefully therefore nitrogen), too rapid an addition caused the gas to become brown. The temperature rose to about 90 C and the evolution of gas was vigorous. When the reaction subsided I evaporated the solution down to about 20-25ml on a steam bath and let it cool. About 6g of sodium nitrate rhombs crystallised out, they were filtered off but weighed damp. The filtrate was warmed to about 70 C and the 40ml of 50% nitric acid added dropwise. It took quite a while before any reaction started but when it did the mixture boiled steadily throughout the addition, much brown NO2 evolved. When the reaction subsided it was cooled in an open bowl to allow further evaporation. The pale orange yellow liquid was chilled overnight but no crystals formed so it was neutralised with 50% NaOH solution, still no crystals formed so the solution was evaporated from about 40ml to 20ml; copious colourless crystals appeared as evaporation occurred. When no further evaporation appeared to occur the slurry was cooled and then filtered, The cake comprising almost colourless crystals weighed 6.47g is yet to be investigated and a viscous orange-brown solution which is currently being evaporated further on a hotplate.

The reaction of nitrous acid with beta-alanine yield 3-hydroxypropanoic acid and nitrogen but without a mineral acid it is very slow. The former dehydrates easily to acrylic acid but I am not sure how easily this occurs in aqueous solution or how important this is given that the intermediate product wasn't isolated but th reaction temperature at times reached boiling point. However, the viscosity of the final filtrate suggest that some polymerised acrylate like material is present. My work-up plan is to treat the latter crystals with a little nitric acid, evaporate to dryness on the steam bath and leach out any malonic acid with alcohol. Watch this space.

I may try this reaction again using beta alanine and 50% nitric acid with just a catalytic amount of sodium nitrite to generate the initial nitrous acid. I am also going to try Magpie's 1,3-propanediol method now I have the diol.

[Edited on 28-10-2022 by Boffis]

Boffis - 31-10-2022 at 12:18

Well the proposed nitric acid oxidation of beta alanine with a trace of nitrite to act as catalyst seems to work nicely, although I haven't characterised the product yet. I tried various methods but the best seems to be to moisten 10g of beta-alanine with a few ml of water and warm it on a steam bath in a ceramic bowl. When it is hot to the touch, c 70 C, remove from the heat and add 11-12ml of conc. nitric acid slowly, drop by drop at such a rate that the frothing is manageable and only the slightest brown NO2 is generated and the temperature runs at around 90 C. Have a bowl of cold water available to cool the reaction if it gets too frisky. When the addition of nitric acid no longer provokes vigorous effervescence the reaction is done. Return to the bowl to the steam bath and steam for a couple of hour to drive of most of the remaining water to leave a viscous yellow liquid which solidifies completely on cooling.

I am currently researching the recrystallisation of malonic acid; has anyone got any experience of recrystallisation solvents for this acid. I have checked out "Purification of laboratory chemicals" but they recommend water, acetone or a complex mixture of benzene etc.? Water would be nice but the solubility is so high a lot will be left in the filtrate. Anyone got experience of acetone?

kmno4 - 1-11-2022 at 22:34

Quote: Originally posted by Boffis  

I am currently researching the recrystallisation of malonic acid; has anyone got any experience of recrystallisation solvents for this acid.


I do not have such experience, but there are many papers giving solubility of malonic acid in many solvents and their binary mixtures (THF, IPA, ethanol, EtAc, dioxan, MeCN, acetone... etc)
For example here:
https://doi.org/10.1002/ceat.201700227

Pumukli - 3-11-2022 at 11:08

I could not resist and tried to make malonic acid via the nitric acid oxidation of malic acid.
Well, it was a failure as far as I can tell.

No oxidation took place, at least nothing obvious (no NOx development), though I tried to "boost" the process with a few milligrams of NaNO2 too. :)
The acid was not concentrated, only around 50-55%, but the temperature was above 70 Celsius.




kmno4 - 5-11-2022 at 14:25

Quote: Originally posted by Boffis  
Well the proposed nitric acid oxidation of beta alanine ....

I made some literature research, no procedure I found describes formation of uniform product in case of oxidation of aminoacids.
Becuse strong acid is used, the first step is formation of ammonium salt, formation of some diazo compound in this case is highly doubtful and if even, it does not explain further reactions.
Besides, oxidation of some organic compounds by HNO3 gives N2O as product of nitrogen reduction - it may be mistaken with N2.
As I said earlier, formation of complex mixture of products, even if more malonic acid is formed, makes further work up cumbersome.
And the more HNO3 is used in higher temperatures, the more (COOH)2 is always formed.

Boffis - 8-11-2022 at 14:56

@ kmno4; Well I have something to report but I am not quite sure what!!

I ran a 20g batch of beta-alanine and obtained a workable amount of beautiful colourless crystals up to 30mm long. It melts without decomposition if heated carefully to a clear liquid and then as the temperature climb gives of gas an decomposes. I heated quickly on foil it melts then suddenly puffs away. I have set up a melting point jig so I'll run a more accurate test tomorrow but the Mp appears to be <90 C. (beta alanine 207, Malonic acid 135)

My original idea was that the presence of nitrous acid or a proxy would replace the amine group with a hydroxy group producing 3-hydroxypropanoic acid would could them be oxidized by the nitric acid. The production of reduced nitrogen oxides as the oxidation proceeds would convert more beta alanine to the hydroxy acid and so the reaction should be self-sustaining until the amino acid is used up. However, the product does not appear to be malonic acid.

In my searches I came across a couple of interesting examples of nitric acid oxidation of simple esters (eg ethyl acetoacetate) to produce furazan or furazan-2-N-oxide derivatives. These compounds often have fairly low Mps and are often energetic.

Other possibilities are things like tartronic acid (hydroxymalonic acid Mp 157) but the Mp is too low.

By the way if you try these experiments don't try recovering the wash acetone from the recrystallisation. When the acetone is distilled it results in a violent decomposition rather suddenly in spite of the fact that free nitric acid has been almost totally removed. The impurity in this reaction is a water soluble yellow oil that deflagrates quite readily!!

The plot thickens!

kmno4 - 9-11-2022 at 02:04

Oxidation of organic matters by HNO3 has free-radical mechanism and is not very selective. Of course, same HNO3 is not responsible for hydrogen abstraction from the organic molecule (as it happens usually), but its oxides do this (because NO or NO2 acts as radicals, but N2O does not). Additional complications is nitration and nitro-esters formation when too concentrated HNO3 is used. Usually, concentration below 20% is used, to avoid such reactions. Very common is 10% HNO3 as oxidation agent.
Of course, there are many organic compounds giving large yields of desired oxidation products even when conc. HNO3 is used.
But the dependency of oxidation-nitration properities of HNO3 (depending of its concentration) is well established.
As I wrote above, -NH2 group is protonated under acidic conditions and becomes partly inert. For example, reaction of phenylalanine with aq. HNO3 gives p-nitrophenylalanine in rather good yield, -NH2 is retained.

Boffis - 9-11-2022 at 11:18

Well, carried out a Mp test on my white crystals and got a figure of 93-93.5 C; the compound melted sharply and without decomposition. Any ideas? The sharp melting point suggests a pure compound and it is obtained in high yield; 20g of beta-alanine gave 31g of product and after recrystallisation and washing in acetone 26g, this is far too high for any simple oxidation product it must incorporate some part of the nitric acid. Clearly this is a very complex reaction but worthy

By the way if you think furazan derivatives (Oxodiazoles) or furoxans (Oxodiazole-N-oxides) are not that likely check out some of the threads on SM and in particular a reference posted by Dany:

1] Snyder, H. R., & Boyer, N. E. (1955). The Synthesis of Furoxans from Aryl Methyl Ketones and Nitric Acid1. Journal of the American Chemical Society, 77(16), 4233-4238. doi: 10.1021/ja01621a021

kmno4 - 10-11-2022 at 18:32

Quote: Originally posted by Boffis  
Well, carried out a Mp test on my white crystals and got a figure of 93-93.5 C; the compound melted sharply and without decomposition. Any ideas?

I can be everything (almost).
But if you like furoxan-like matters, here you are a candidate:
furoxancarboxylic acid (I am not sure if it is correct name)
https://archive.org/download/crossref-pre-1923-scholarly-wor...
.... and find page 66. The structural formula is not fully correct in this old paper: the oxygen bridge is not good.

Boffis - 11-11-2022 at 12:15

Hi kmno4, thankyou for the paper, I haven't seen this one before but I have looked at, and indeed translated several others on "glyoxime peroxides" as part of my investigation into fulminic and fulminuric acid.

I have found online a book on the furazan and furoxan heterocyclics and there are lots of examples of nitric acid oxidation of various ketones and keto-acids. I have attached a copy of the Synder paper.

beta-alanine to furoxan.gif - 20kB

Looking at the published literature there are two possible reaction routes but neither is quite applicable to a beta-aminoacid. In one route the nitrogen oxides attack the amino group and somehow generate a nitrile oxide rather than a diazo compound. I can't find any info on the furoxan-diacetic acid. My original idea was that a transient diazo compound formed that then hydrolysed to the hydroxy acid which was then simply oxidized to a second acid group is not tenable in view of the results.

In the second, more likely, route nitrous acid from the nitrite attacks the alpha carbon to the carboxylic acid group forming a isonitroso group while the amine is oxidised to a nitroso group that rearranges it the isonitroso form and is then oxidised and cyclotises to the furoxan carboxylic acid. I prefer this latter route.


Attachment: The preparation of furoxans by oxidation of methylketones with nitric acid JACS 1955.pdf (640kB)
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[Edited on 11-11-2022 by Boffis]

kmno4 - 12-11-2022 at 00:01


The "diaceto" derivative would have higher m.p. than the monocarboxylate furoxan, at least I think so.
You may do some NaOH titration of your compound and/or make some tests described in this article from Annalen. The most possibly your preparate is purer and gives higher m.p. than noted there (89-91 C). The Ag salt is "explosive", as noted elsewhere, but many Ag salts of "nitrogen-acid" do so.

I would name your reaction as "Boffis reaction", but somehow I have impression that it is too simple and someone must have done it earlier. However, I think that making something new, a reaction or a compound, is not very difficult even at "home-chemistry" level.
The chemistry is the endless sea of possibilities ;)

P.S. I am going to do some additional literature research, but maybe SciFinder or similar tool would be more helpful (I have no access now)

[Edited on 12-11-2022 by kmno4]

Boffis - 12-11-2022 at 07:46

I agree with you kmno4 about the mp of the diacetic acid and I find this route rather implausible too. Apart from Synder's paper I have read many papers that produce what are clearly furoxans, although usually referred to as glyoxime peroxides, with nitric acid including the original paper by Propper and several by Ulpiani. Unfortunately other interesting paper by Ponzio and Quilico are in issues of Gaz. Chim. Ital that are not readily available (up to 1923 is available at archive.org but these two latter authors mostly published around 1926 to 1938. I don't have access to scifinder either, any volunteers out there that do?

I have just been preparing salts of the compound and got some weird results that suggest the compound is not furoxan carboxylic acid. It does not appear to be decomposed by the amount of NaOH required to neutralise it and the resulting solution can be evaporated on a steam bath. There is no ppt with either ammoniacal silver nitrate or 2M silver nitrate solution with either the free acid or the neutralised acid and the barium salt is also very soluble.

I originally thought that it might be a compound oxidised in the central carbon like tartronic acid or mesoxalic acid but the former melts at 157 and the latter is so unstable that it can't be isolated in solid form but could it be a nitrate ester of either tartronic acid or 3-hydroxypropanoic acid?

I am also becoming interested in the yellow energetic, water soluble oil that accompanies it after reading that many of the furazan and furozan compounds are viscous liquids. I am being sent overseas with my work soon so I will loose access to my lab until Christmas so I am running out of experimental time.

kmno4 - 13-11-2022 at 07:58


OK.
As a matter of fact, it is really hard to guess correct structure of the product without elemental analysis, IR spectra.... etc.
I would make a test with NaHCO3 sol. to see if your substance is acidic (carboxylic) at all. The crystal form may also suggest some oxime, many of them form large long crystalline needles. Possibly a test with Ni salts (in alkaline conditions) would also show something. Besides, its Ag or Ba salt can be water soluble, who knows....

BTW, the yellow oily matter can be also whatever: some nitro derivatie, nitrate ester, nitrosoamine ... etc, also in multisubstituted versions.

[Edited on 13-11-2022 by kmno4]

Boffis - 19-1-2023 at 13:05

Hi kmno4. I haven’t replied to this thread earlier as when at home over the Christmas period I was rather ill and didn’t really feel like doing any chemistry and I am now overseas again for a while. However, I have been doing some reading into this subject and found some old but rather interesting papers. You are quite right, I am just guessing about the identity of the my mysterious compound but not having access to physical measurements other than melting point my method of working is; “guess the identity then check the literature for its properties, do they match; -yes, whoopee –No, back to the guessing game” technique.

You might think that every possible C3 derivative of propanoic and malonic acids has been prepared but much of the information on these compounds is very old and many have not been isolated in a satisfactory solid form. One such compound is the theoretical 2-oxime of mesoxalic acid semialdehyde.


Van Slyke developed a method1,2) for the determination of amino-acid amino groups by treating the acids with sodium nitrite in acid solution. Some amino acids give slightly anomalous results and during a follow-up investigation by Schmidt4) it was found that beta-alanine reacted like a normal amino acid and rapidly de-aminated, presumably to beta-hydroxypropanoic acid though this isn’t expressly stated. The reaction is essentially complete in 3-5 minutes. So if 1,3-propandiol is oxidized by nitric acid to malonic acid one would expect the hydroxylpropanoic acid to be an intermediate and yield the same product, in fact this is expressly stated in von Richter’s textbook of carbon compounds. So I would expect malonic acid to be the end product of nitric acid oxidation. However, in my final experiment I didn’t add any sodium nitrite so the oxidation route is much less clear. One slight complication is that beta-hydroxypropanoic acid, which is a well-studied intermediate for bio-polymers(see Wikipedia), readily dehydrates to acrylic acid and this may react differently towards nitric acid too. A further problem I see is that an oxime group in the 3 position allows it to cyclotise to an oxazolone derivative.

When I am home next I will try nitrous acid de-amination of beta-alanine then nitric acid oxidation in separate stages to see if I get the same material. I may also try repeating Magpie’s procedure to see what I get.

I also intend to try treating the product with hydroxylamine to see if it has any carbonyl groups in it.

While rummaging through the old literature I came across another paper investigating the reason for the excess nitrogen by Austin3) in which he concludes that one of the products of de-amination of glycine with nitrous acid are things like methazonic acid and fulminic acid and that the polymerization and decomposition of these material leads to the formation of excess nitrogen. Incidentally this paper has been posted before, I think it was on chemplayer’s thread on "essence of smirf" which is described in the latter part of this paper.

1 The reaction of alpha amino acids and related with nitrous acid JBC Van Slyke 1911 v09 p185
2 Quantitative determination of aliphatic amino groups JBC Van Slyke 1912 v12 p275
3 Deamination of amino acids by nitrous acid JCS A T Austin 1950
4 The reaction of nitrous acid with certain amino acids at 45 C JBC C L Schmidt 1930 v82 p587

References 1,2 and 4 are available from the Journal of biological chemistry web site freely.

Attachment: 3 Deamination of amino acids by nitrous acid re methylnitrolic acid & fulminates JCS A T Austin 1950.pdf (205kB)
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