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Author: Subject: PEA and mek -> NPP?
Sauron
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[*] posted on 15-3-2009 at 00:15


Probably because drug cookery is discouraged here, and 4-piperidone has little use other than making opioids.

Furthermore spoonfeeding requests are also frowned upon.

You cite no literature and show no evidence of having a clue.

There are quite a few preps of piperidine which have been discussed, one very recently from pentamethylenediamine (cadaverine). It ought to be clear that a carbonyl group in the appropriate position in the acyclic precursor will be unaffected by the ring closure and that 4-piperidone would result. My point is, have you searched for analogous preps of piperidine that can be modified? Apparently not.

Just asking for this information on a platter is asking for spoonfeeding.

Scholars help scholars who get stuck but have little time for the terminally indolent.

And that goes double for those just trying to squeeze a little joyjuice out of chemistry.

The appropiate compound would be 1,5-diamino-3-pentaneone.

H2N-CH2CH2-C(=O)-CH2CH2-NH2

See the cadaverine thread for that cyclization.

I do not know if the ketone stinks like cadaverine, let's hope not.

How to get to the intermediate?

Figure out how to make the corresponding glycol:

HO-CH2CH2-C(=O)-CH2CH2-OH

and chlorinate it or brominate it then treat it with conc NH4OH.

An obvious precursor to the keto glycol would be the trihydroxy compound 1,3,5-trihydroxypentane which you can selectively oxidize to the keto glycol with TCCA. The primary hydroxyls are unaffected.

That keto glycol looks vaguely like a citric acid derivative.

[Edited on 15-3-2009 by Sauron]




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[*] posted on 15-3-2009 at 02:16


Starting with citric acid, you can apparently make its triamide, then dehydrate it into trinitrile, then eliminate the mid. CN group with KOH to get a useful byproduct KCN, the ketone is reduced by LAH to 1,5-diamino-3-pentanol and oxidized to corresponding ketone (then it is treated like cadaverine).
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[*] posted on 15-3-2009 at 02:37


Got any lit. on that?

Or is this old rhodium stuff?

The dehydration of the triamide, how? P2O5, POCl3, PCl5 if so this will be out of reach for most. Almost certainly for the thread author.

LAH is also a deal killer for many.

How about going directly from citric acid to acetonedicarboxylic acid (3-ketoglutaric acid) and reducing that to the trihydroxy compound (catalytically most likely) which gets you the starting material and then proceeding as I outlined above?

1. TCCA to the keto glycol
2. Chlorinate to the keto dichloride (bromination may be better)
3. Aminate w/ conc NH4OH

No restricted phosphorus reagents, no restricted LAH.

Acetonedicarboxylic acid is easy to make if you can get oleum. Just watch out for all that CO formed. Hood, or outside.

[Edited on 15-3-2009 by Sauron]




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[*] posted on 15-3-2009 at 06:13


What lit? It must be a very kewl person who attempted this pathway, usual chemists haven't ever done it i believe.
Quote:
1. TCCA to the keto glycol
2. Chlorinate to the keto dichloride (bromination may be better)
3. Aminate w/ conc NH4OH

now its your turn (lit) :D
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[*] posted on 15-3-2009 at 09:24


For formation of acetonedicarboxylic acid from oleum, smartass, try my thread on things to do with citric acid; also axt's thread on DINA which is made from the same intermediate (ADCA) and both of us posted many papers on the reactions of citric acid with conc H2SO4 or (better) 15-20% oleum, UTFSE. Also see Org.Syn for prep of acetonedicarboxylic acid and references therein. All this was posted long before you ever joined this forum, but still.

Also a thread I did on prep of citrazinic acid which bears similarities to your proposal.

Org.Syn. also has prep of the di-ester (methyl or ethyl) of ADCA and I or someone else posted the prep of its cyclic anhydride which is prepared from ADCA and Ac2).

It does not take lit. to envision the catalytic hydrogenation of ADCA to the trihydroxy-3-pentanone, the TCCA selective oxidation of sec. hydroxyls has been posted here before, the halogenation of the keto glycol is trivial and so is its aminolysis.

It would be a good idea to do a literature search to pin down (hopefully) atm. or low pressure conditions and catalyst for hydrogenation of ADCA. I have a pressure reactorr but not many do, so a 60 spi procedure that could be done in a stirred Parr bottle would be more convenient for most.

Some people like conc HBr for alkyl bromide preps, I favor TCT/DMF/KBr. The lit. on that one has been posted several times.

Since I have zero interest in 4-piperidone I am never going to prepare it and so I will leave it to somneone who is more motivated to dig out the as yet unearthed lit. ADCA etc are a different story, been there, done that, posted already.

And yes it can be done with conc H2SO4 but the yields are shit compared to using oleum.

[Edited on 16-3-2009 by Sauron]




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[*] posted on 15-3-2009 at 09:53


Ok, you won. You have provided literature so thats fine. Just let BobHawson to have a go (still, maybe try with cadaverine first to work out the procedure and not to flunk the last step with diaminoketone).
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[*] posted on 15-3-2009 at 10:31


It wasn't my stinky corpse juice. That was someone else who wanted to dry-distill it from lysine, see his thread. Ugh. He claimed he was just doing it out of curiosity, uh-huh. Cadaverine is a well known precursor to piperidine, so I guess we all know what that guy had in mind.

Master Hawson framed the question, how to make 4-piperidone from other than piperidine.

I merely wanted to demonstrate to him how chemists think. His problem was tractible. He's just not a chemist. I offered him an object lesson, not a spoonfeeding. I doubt he can make use of my route any more than he could get PCl5 and LAH to essay yours.

If I WANTED 4-piperidone I would probably start with pyridine and go from there, with a nuclear reduction in between maybe to a hydroxyypiperidine that can be mildly oxidized. A 5 minute review of pyridine chemistry in Ullmann's would probably tell all.'

But I do not have any use for it. I am past get rich quick schemes and certainly have no desire for instant incurable acute Parkinson's.

[Edited on 16-3-2009 by Sauron]




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[*] posted on 15-3-2009 at 19:18


Parkinson's? Is the discussion about the synthesis of MPPP which under certain reaction conditions leads to the side-product MPTP (to be consumed)? No, it is not. It is interesting that you first take a "moral" stance against the "drug cookery" thread only to become the most active contributor in it. hahaha... ;)

[Edited on 16-3-2009 by Sandmeyer]




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[*] posted on 15-3-2009 at 21:23


There is a lot of literature available through ACS on synthesis of piperidones. It's mostly done by the Dieckmann route. The intermediate compounds are alos covered in papers by McElvain and others, Baty, Jones & Moore and Beckett, Casey and others to name a few. Do some homework. When you have iden tified a specific paper ask for help getting it in refs if you don't have journal or library access. I don't see how you missed the rather too much discussion here if you searched. At least one of the papers was posted in a thread on piperidones. As Sauron says, they're mostly used in medicinal chemistry. I like them for other reasons and spent some time with them last year.



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[*] posted on 15-3-2009 at 21:23


Sandmeyer, as usual, I couldn't give a damn about what you think is "interesting".

What you characterize as a "moral" stance is nothing more or less than the current forum policy, no cook threads and no spoonfeeding.

The thread author exhibited neither interest in the chemistry of piperidones nor any scholarly effort to ferret out the literature on same beyond an obviously superficial and unsuccesful search. This is the sort of thread Nicodem loves to close precisely on those grounds. The thread author was doing nothing but asking for a synthesis - in effect a recipe.

So you see, "morality" has nothing to do with it. If you don't like the policy, take it up with the management, not with me.

BobHawson's other threads are revealing. Have a look. PEA -> NPP so I don't think it is inappropriate to conclude he is after opioids such as the infamous super-demerol.

The guy appears clueless, so let's not paint him as some world class medivinal chemist all of a sudden.

[Edited on 16-3-2009 by Sauron]




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[*] posted on 15-3-2009 at 23:55


These latest thread was anything but informative and all it gives to this forum is one more opioid thread. One such thread would be more than enough, this is why I'm merging it with the longest one. No more new threads regarding piperidin-4-one and opiods in general - use the existing ones!
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[*] posted on 16-3-2009 at 02:48


The decarboxylation of lysine to produce cadaverine was described in Ber. 18, 2956 (1885), and I think the same procedure would apply to the diamino-3-pentanone prepared from citric acid.

The Dieckmann condensation of a suitable diester would require Na or preferably K metal or freshly opened potassium alkoxide. Na metal is not too hard to come by, potassium is rather dear, I have 6 Kg Na but only 250 g K.

Nicodem, I have a use for dilute solns of piperidine in Fmoc-streyegy peptide synthesis as a deprotection reagent, and buying piperidine is a pain in the ass everywhere because of the anti-PCP regimes. So making my own is attractive. I do not, as stated above, have any use for 4-piperidone, but chemrox does and he is no drug cook. No one is discussing how to make opioids per se. (Well not in this piperidone thread anyway. I think NPP is closer to the mark.)




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[*] posted on 16-3-2009 at 03:27


Quote:
Originally posted by Sauron
Nicodem, I have a use for dilute solns of piperidine in Fmoc-streyegy peptide synthesis as a deprotection reagent, and buying piperidine is a pain in the ass everywhere because of the anti-PCP regimes. So making my own is attractive.

Those who are too annoyed by the paper signing when buying piperidine for Fmoc deprotection are now using piperazine for this purpose, at least that is what I have been recently told by a biochemist. I bet morpholine or pyrrolidine would work just as well. There is no need to stick to piperidine just because historically it is the reagent of choice for this deprotection.
Quote:
No one is discussing how to make opioids per se. (Well not in this piperidone thread anyway. I think NPP is closer to the mark.)

Already using such drug cook acronyms like "NPP" says more than enough about the intentions of the original poster and others involved in this thread. Not to mention the kewlish discourse used here, or the asocial form of posting of members like BobHawson and the like. For some reason most members that ask about opioids synthesis just have this need to shout to the whole world about their intentions.




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[*] posted on 16-3-2009 at 03:39


Oh, I absolutely agree about conducter and BobHawser and their ilk, I would think I make that perfectly clear. I agree that they broadcast their intentions about as effectively as the Goodyear Blimp over a packed stadium with an electronic signboard.

But BobHawser vanished like a vampire at the sight of the True Cross as soon as a few of us took over this thread. And conducter is nowhere around either.

Peptide chemists are rather conservative about reagents and often loathe to switch. I understand your reasoning that any old 5 or 6 membered secondary N-heterocycle ought to do as well as piperidine. But peptide chemists will turn up their noses at the suggestion. This personality trait has been remarked upon in the literature of peptide synthesis.

Piperazine itself is anyway under DEA scrutiny because of abuse of N-benzylpiperazine (horse cathartics if I recall) as rave drugs or some such. So that one is likely to be a problem in the future if not already.

I have never tried to buy piperidine here but a friend is a professor of molecular biology at a med school in Lausanne and he has been kicked upstairs into admin and described to me the paperwork the Swiss antidrug agency makes the university do to buy 5% solutions of piperidine for their peptide work. Next time I see him I will ask him about piperazine. Recently he was complaining about the shortage of acetonitrile worldwide.

[Edited on 16-3-2009 by Sauron]




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[*] posted on 18-3-2009 at 17:31


Thanks for your replies folks!

I was waiting to post until some people had responded.



Now, anyone know of routes to piperidone that DO start with piperidine?

I have uts engines and know of no posts or literature on the conversion of piperidine to piperidone, though wikipedia says that piperidone is a derivative of piperidine. I don't know if this could be done on a lab scale, or wouldn't be practical.

[Edited on 18-3-2009 by BobHawson]




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[*] posted on 18-3-2009 at 18:37


Just because something is a derivative of something doesn't mean it can be made from that something (easily anyway).
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[*] posted on 18-3-2009 at 21:43


Again, as Nicodem implies, there are already many posts on the subject here and if one looked a lot of the relevant literature has also been posted. Did you not hear the part about spoonfeeding? Having devoted the better part of a year and half to 4-piperidones (but not opioids thank you) I can tell you that pyridines and piperidines are not very good ways to make them. Cyclizations and addition reactions are employed. Even that old friend of yours and mine the Diels Alder has been utilized. FYI: in the opioid literature piperidones are gateways to piperidinyl moieties. Starting from piperidine would be backwards. Maybe it would be worthwhile for you to pick up one of those guides to chemical research. Not searching the literature as far as you are able will only earn you resentment and contempt. Moreover, there's a mod that waxes indecorous when this subject comes up. Maybe you should peruse the thread and send out a few pms after a search through the refs and a trip to the library. Pay heed to the words just posted by ergoamide. Also, out of his innate compassion, our friend Sauron did pretty much spoon feed you the general synthetic approach. Thank him and do some homework.

[Edited on 18-3-2009 by chemrox]




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[*] posted on 19-3-2009 at 00:18


I am very preoccupied with downloading 110 years of JACS volumes at present and after that I have a couple dozen large chemistry books to scan so I am afraid I have little time to help with this. Sorry.

By the way I regard any sentence starting with "According to Wilkepedia..." as epistomologically invalid. And if you do not know what epistomology is, look it up. It is a term the Jesuits pounded into me.




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[*] posted on 8-5-2009 at 21:14


This thread is long finished except that I felt I had to weigh in on the Wikipedia question. Wikipedia articles are written by volunteers and often carry the hope with them that another volunteer author will come along and correct the one first offered. That indeed makes them epistemologically invalid or suspect which ammounts to the same thing. Than k you Sauron.



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[*] posted on 8-5-2009 at 21:31


Ill have to go check Wikipedia to see if I can find out what epistomologically means.




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[*] posted on 8-5-2009 at 21:39


Try the OED instead. Wiki is for pinheads.



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[*] posted on 6-4-2010 at 16:31


I thought I'd follow up on this discussion with some experimental results. The PEA method works but the yields aren't great. Since that experiment I started making esters of various phenethyl cmpds; alcohol, halides, aldehyde. The results with acids including oxalic, anthranillic, propionic, acetic, citric yielded rosy flavors ranging from fruity and sharp to musky and bergamot like. I've been wondering if the method of using 4-piperidone HCl·H2O, Na2CO3 and phenethyl Br fails because the phenethyl compounds are too acidic. Maybe stronger base would have worked as suggested in a patent on ANNP (Indian). The esterifications mentioned above are *very* easy. The Indian patent is easily found for those wanting it and I shan't post it here for two reasons; bandwidth and I don't really want to encourage further delving into this area. However, the problem of failure of the N-alkylation by way of the halide bothers me. Maybe I'll try it with 4N NaOH sometime to see how it works. Also using the Cl rather than the Br cmpd. If I get around to it I'll write back with some details.



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[*] posted on 8-5-2010 at 08:33


Could someone give me a link to an explanation of this reaction? I am not quite understanding the mechanism of this reaction, what is it called?
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[*] posted on 30-3-2011 at 00:14


I apologize for this being my first post, for diggin it up from the depths, and for making it so "TL;DR"

I noticed this thread while thinking about this topic, mostly for fun (because who is honestly going to undertake this and ruin their career in chemistry).

I was thinking about how to make the dominant structural features for a convergent synthetic scheme by utilizing the absolute bare minimum of watched precursors (because it is absolutely impossible to achieve this synthesis by avoiding the use of chemicals watched by LEO). I realized that the main structural elements do indeed have synthons that are readily preparable from ubiquitous materials, and possibly even utilizing several multi step 1-pot reactions (without intervening purifications, just "add this, heat, add this, heat, etc")

Obviously the main core unit is the PEA, but like most of the posters here, I realized that construction of 4-piperidone might be possible and did the same googling and Scifinder-ing that everyone else did (Still have VPN access to my old institution's network, so I still have journal access and I have the Scifinder 2007 application installed, as opposed to the we based utility which sucks in comparison).

anyway, I stumbled upon that same intermolecular mannich followed by intramollecular mannich: amine+2xaldehyde+ketone prep.

The question of will formaldehyde work instead of benzaldehyde? my guess is yes, but the reaction conditions would have to be amended to optimize the yield of the target material. With formaldehyde, the imine/iminium ion intermediate (imine because either PEA or ammonia can be deprotonated to the neutral imine) is wildly reactive and will react with literally anything in solution, be it solvent or unreacted (or completely reacted target material) ketone or amine or impurity.

on the other hand, the benzaldehyde intermediate: phenyl-CH=N-R,H (where R is ethyl amine if you used PEA or H if you used ammonia, and I have written the structure as the deprotonated, neutral imine, not the iminium formed by a 2ndary amine mannich.) is very stable, with a large amount of resonance stabilization energy. why is this important? it means that the intermediate persists long enough for the ketone to diffuse through the solvent and encounter the intermediate with the right energy and orientation, which depends (as usual) on a Boltzmann distribution (as usual for encounter pairs in solution.... just like the old days of the Marcus Cross relation and the Eigen Fuos mechanism for inorganic electron transfer reactions, lol)

furthermore, in the NEXT mannich (on the "other side" of the carbonyl, so to speak), the intermediate Is, yet again, stabilized by the phenyl conjugation (though the effect is less significant, because this reaction is intramolecular, so the free energy stabilization is not as pronounced, due to a major entropic consideration). basically, if you ran the reaction with formaldehyde, the initial imine intermediate would react so quickly that the target material would be formed in precipitously low yield. but then again, who cares... its just formaldehyde.... if you run the reaction with ammonia and formaldehyde... who cares, that stuff is cheap and LEO really cannot fault you for buying paraformaldehyde and ammonia. you are just cleaning your floors and acting as an amateur entymologist (the formaldehyde)

and for the sake of completion....

the question is, what is the absolute bare minimum of "watched" chemicals?
if you can get a borane, PCC (pyridinium chlorochromate), H2, Pd/C (palladium adsorbed on carbon), styrene, aniline, various solvents, glassware, electronics (oil baths, mantle, stir plate, etc), tools (syringes, septums, etc), silica gel, celite, etc. and SOME synthetic equivalent for propionic acid.... molecular sieves (3-4 Angstrom) would be ideal as well

example:

styrene + 9-BBN ---> PCC ----> (1 pot, sequential) 2-phenyl-ethanal

no need for alkaline hydrogen peroxide, the PCC oxidizes the trialkylborane directly to the aldehyde (yes I have the reference, it is in my Advanced Organic texbook, by Zweifel, as an example with the reference which is from 1980)

2-pheny-ethanal + 4-piperidone ----> N-styryl-4-piperidone (enamine) + freshly distilled aniline ----> the imine adduct...

this is a 1 pot sequential reaction. no isolation, no change in solvent or reagent conditions.

H2, Pd/C (helps to be run under ~30 atmosphere) will reduce the imine and enamine but leave the phenyl groups. yes. I have references for this. remember, the reaction WILL proceed at ~1 psi guage pressure, but it will take forever (like weeks of stirring under H2). high pressure just speeds it up, nothing more.

the question is how to add the synthetic equivalent for propionic acid without using propionic anhydride or propionyl chloride or getting DCC or other activating agent. my advice would be to make propionaldehyde from propene (propylene) using the same synthetic methodolgy employed above with styrene.

form the simple aldol with reduced diamine listed above, but prevent the reaction from proceeding further to the ene-amine (prevent dehydration), and oxidize the amino alcohol intermediate with the "already obtained" PCC to the amide.

this, again, is theoretically a 1 pot, sequential addition reaction with no intervening isolation/purification. there are some concerns about formation of Chloro-amines, but in the presence of the pyridine itself, I think this would be fairly limited.


this exact concept (amidation of an aldehyde synthon) is actually a currently pursued area of research... many researchers have found various catalytic systems employing copper salts or other peroxides to furnish the intended amide (usually in the form of an amino-aldol, followed by alkoxy oxidation of the amino alcohol).

the absolute final step would be chromatography. each reaction listed above can be run using a filtered crude reaction mixture from the previous step. even the oxidation of the alkylborane will produce a filterable precipitate, and the side product can come along for the ride. the only genuine "isolation" steps would be filtration of any soldids, then drying over sodium sulfate and evaporation of the solvent. the biggest issue would be the use of any high BP solvents like DMSO, which requires long duo-seal vacuum pump time, or lyopholization.


I should note, I mentioned above that you might use the acetone dicarboxylic acid. here are some useful Decarboxylation methodologies:

1) the usual strong acid, high concentration, high heat
2) catalytic Cu2O in a polar-aprotic solvent at high (but not super high temp)... think MeCN at 90 C
3) DMAP in pH 7 buffered H2O/toluene at 90 C
4) LiI in H2O/DMSO or H2O/Collidine at reflux
5) Heating with Boric Acid

[Edited on 30-3-2011 by mongler]
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[*] posted on 30-3-2011 at 18:01


Petrenko-Kritschenko synth of piperidones
put this under your cap.

http://en.wikipedia.org/wiki/Petrenko-Kritschenko_piperidone...

sauron i remember you ranting on about the jesuits long ago they must have done something to shape your thinking.
i know they are some strict teachers.


it looks like if unsubstituted piperidones could be made this way they would have been already.

nope nope it is double micheal addition of methylacrylate to phenylethylamine followed by diekmann condensation and, saponification

phenylethylpiperidone can also be made from methyl piperidone by exhaustive methylation with MeI then heating in an excess of phenylethylamine if anyone wants that reference pm me.


[Edited on 31-3-2011 by jon]

[Edited on 31-3-2011 by jon]

[Edited on 31-3-2011 by jon]

[Edited on 31-3-2011 by jon]
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