Sciencemadness Discussion Board

Lovely Smells

Waffles SS - 2-7-2013 at 08:50

I create this topic for introducing chemicals that cause Lovely smell Like Fruits,Flowers and finding method for preparing those.
I hope everybody help me in this topic.

The smells of fruits are due to the presence of complicated mixtures of chemicals,
For example:
Pentyl acetate (Pears)
Pentyl alcohol + Acetic acid

Iso amy acetate (bananas)
Isoamyl Alcohol + Acetic acid

Octyl acetate (orange)
Octyl Alcohol + Acetic acid

Ethyl butyrate(Pineapple)
Ethyl Alcohol + Acetic acid

Methyl butyrate(apple)
Methyl Alcohol + butyric Acid

Methyl anthranilate(grape)
Methyl Alcohol + Anthranilic Acid

Somebody know what is ester or component in smell of Cantaloupe ,Watermelon,Chocolate,Cucumber,Strawberries?


[Edited on 3-7-2013 by Waffles SS]

Magpie - 2-7-2013 at 09:05

This is one of my favorite parts of chemistry. I have been working on OTC methods of making isoamyl alcohol just so I can make the banana oil, isoamyl acetate.

Here's my only contributions so far:

benzaldehyde (almond oil) - a really lovely smell, IMO
Ethyl ß-Naphtholate (Nerolin) - notes of citrus and vanilla
methyl salicylate (wintergreen)

adamsium - 2-7-2013 at 09:28

(R)-carvone: spearmint
(S)-carvone: caraway

It's interesting that an enantiomeric pair can have such different smells.

Mailinmypocket - 2-7-2013 at 09:34

Pure vanillin smells wonderful, when I ordered some I could smell my mailbox a meter away and knew it had arrived :P

Random - 2-7-2013 at 10:31

Quote: Originally posted by Magpie  
This is one of my favorite parts of chemistry. I have been working on OTC methods of making isoamyl alcohol just so I can make the banana oil, isoamyl acetate.


You are not the only interested in it. One of my favorite fields is aroma and flavor chemistry.

Check out this site:

http://www.thegoodscentscompany.com/

Click on the right side "Odor index" then go there in the newly opened applet and click on "Odor type". You can see all common odors, if you click on each one you can see chemicals that contribute to it.

You think we could synthesize some of them with OTC chemicals?

There is this 2,5-dimethylpyrazine which has a strong chocolate smell. IIRC the reaction goes by isonitrosation of acetone with nitrite, reducing the product with Fe/HCl and then oxidizing it with persulfate I think. Unfortunatelly I don't have any nitrite as of yet.

Also guiacol has smoky aroma and wood creasote which is obtained by dry distillation of wood contains like 20-30% IIRC guiacol. Aldehyde bond can be added with chloroform via Reimer-Tiemann reaction to produce vanillin. By the way guiacol alone is aroma chemical.

Another list can be found on wikipedia but it is rather short. Only listing common ones:

http://en.wikipedia.org/wiki/Aroma_compound

Terpenes are another class of different flavor components but synthesis often requires borohydride reduction. Another chemical I don't have.

[Edited on 2-7-2013 by Random]

Waffles SS - 2-7-2013 at 10:31



Aroma components of honeydew melon:
cis-6-nonenyl acetate, cis-3-nonenyl actetate, and cis,cis-3,6-nonadienyl acetate
Buttery et al. 1982

bfesser - 2-7-2013 at 12:57

Not to rain on the parade, but couldn't this have been incorporated into the already well established thread <a href="viewthread.php?tid=1216"><em>Best and worst smelling chemicals?</em></a>

Some other <a href="search.php?token=&srchtxt=smell&srchfield=subject&srchuname=&f%5B%5D=all&srchfrom=0&searchsubmit=Search">posts of interest</a> turn up with a forum search for "smell" in the subject field.

ElectroWin - 2-7-2013 at 19:03

ok, what's that lovely smell/taste obtained when grilling chicken?

Random - 2-7-2013 at 19:44

Quote: Originally posted by ElectroWin  
ok, what's that lovely smell/taste obtained when grilling chicken?


Probably a mixture of products, you could make the aroma through maillard reaction with certain sugar/amino acid.

Waffles SS - 2-7-2013 at 21:18

Quote: Originally posted by bfesser  
Not to rain on the parade, but couldn't this have been incorporated into the already well established thread <a href="viewthread.php?tid=1216"><em>Best and worst smelling chemicals?</em></a>

Some other <a href="search.php?token=&srchtxt=smell&srchfield=subject&srchuname=&f%5B%5D=all&srchfrom=0&searchsubmit=Search">posts of interest</a> turn up with a forum search for "smell" in the subject field.


This topic is about lovely Smells Like fruits and flowers and finding
method for preparing it.not about worst smells or anything else

madscientist - 2-7-2013 at 21:27

Cadaverine butyrate - roses.

testimento - 3-7-2013 at 22:09

The more carcinogenic the stuff is, the better it smells. Ain't no better smell than benzene, gasoline, diesel, chlorine compounds or even toxic gases. Thank god I've got a bunch of ATEX filters.

phlogiston - 4-7-2013 at 00:43

There's an interesting list of chemicals with notable smells on wikipedia:

http://en.wikipedia.org/wiki/Aroma_compound

bahamuth - 4-7-2013 at 03:14

Quote: Originally posted by testimento  
The more carcinogenic the stuff is, the better it smells. Ain't no better smell than benzene, gasoline, diesel, chlorine compounds or even toxic gases. Thank god I've got a bunch of ATEX filters.


Haha, so true. Mostly anyways...

Pyridine/DMSO and similar reportedly "fishy" smelling compounds smells like berries to me by some weird action on my receptors.

Have a post and made an .xlsx on the smells of many simple esters, Esters and their smells if anyone is unaware of it.

Random - 4-7-2013 at 03:26

Anyone has some way to produce higher chain alcohol like nonanol without buying it? Maybe grignard or something?

Furboffle - 4-7-2013 at 17:55

way to be off topic. but it depends what nonanol you want? 1-nonanol? why not oxidize 1-pentanol with PCC to pentanal. then form your grignard reagent from 1-bromobutane. then carry out reaction to get 5-nonanol.
another way would be with 1-butanol and 1-bromopentane to get 4-nonanol. then if you're looking for 1-nonanol you could reduce either product to nonane. perhaps do a chlorination to get a terminal chloro-compound and then just go from there to your alcohol. but you'll more than likely get a slurry of the different chlorinated-nonyl compounds. let alone possibly poly chlorinated compounds. which separation will suck ass.
it really just depends which isomer you're asking about. you should try mentioning that part.

<!-- bfesser_edit_tag -->[<a href="u2u.php?action=send&username=bfesser">bfesser</a>: removed unnecessary quoting]

[Edited on 7/8/13 by bfesser]

Furboffle - 4-7-2013 at 18:04

theres been quite a few that I've had a fancy for that I just can't remember what they were off hand. but a few that were fancied enough to keep note of:
1. benzaldehyde. I want to pour a bottle all over my furniture and make my house reek of it.
2. tryptamines mainly n,n-dimethyltryptamine. that floral smell I find quite lovely.
3. indole theres something about it. the smell just seems like its toxic but I can't get enough.

[Edited on 5-7-2013 by Furboffle]

halogen - 7-7-2013 at 12:09

Quote: Originally posted by bahamuth  

...
Pyridine/DMSO and similar reportedly "fishy" smelling compounds smells like berries to me by some weird action on my receptors.


Yes! I wondered if anyone else thought pyridine smells like berries! Dilute pyridine and strawberries specifically.

Hexavalent - 7-7-2013 at 12:19

Quote: Originally posted by Random  
Anyone has some way to produce higher chain alcohol like nonanol without buying it? Maybe grignard or something?


For some unknown reason, our school has 5L of nonanoic acid :P

zeved - 7-7-2013 at 22:50

i always loved benzene.
also, nitrobenzene smells really nice, almond like
dibromoethane

nezza - 8-7-2013 at 11:26

Nitrotoluene smells of almonds to me as well. Benzaldehyde is the notable almondy smelling solvent. I like the smell of 1-bromobutane as well, its a bit petrolly and nice.

Hockeydemon - 8-7-2013 at 19:51

Quote: Originally posted by Random  


There is this 2,5-dimethylpyrazine which has a strong chocolate smell. IIRC the reaction goes by isonitrosation of acetone with nitrite, reducing the product with Fe/HCl and then oxidizing it with persulfate I think. Unfortunatelly I don't have any nitrite as of yet.


Where would I find more information on this? I have quite a bit of sodium nitrite that I haven't had a use for. What do you mean reducing it with iron/hydrochloric acid? Would ammonium persulfate used for PCB etching work for the oxidizer?

I've tried to find information on this, but I haven't found much. I could do this in a couple days if I had more information on it.


I would like to make many of these compounds, and I'm making up some sodium acetate in order to make glacial acetic acid right now. I also ordered potassium permanganate & butanol to make butryic acid. Is there any relatively inexpensive way to make these other alcohols (Isoamyl, pentyl, octyl)? I'd rather not spend much more money.

Random - 8-7-2013 at 20:05

Here is the reference, it uses alkyl nitrite but I have read that acetic acid mixed with nitrite (Name reactions in heterocyclic chemistry II) will also produce isonitrosoacetone.

Now from this book in my post I made a year ago says this:
Quote:

I have found a reaction for obtaining 2,5-dimethylpyrazine in Name reactions in heterocyclic chemistry II book. Oxoaminoketone can be made in-situ with acetic acid and nitrite salt along with acetone. Then it can be reduced with zn/hcl, fe/hcl or anything other. Cupric salt can be used for oxidation to obtain dimethylpyrazine.


So if I correctly read the book a year ago, fe/hcl can be used for reduction, cupric salt for oxidation. Persulfate should give best oxidation yield though.

If you can also take photos it would be interesting to see this experiment.





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[Edited on 7/9/13 by bfesser]

Hockeydemon - 8-7-2013 at 23:51

Lol. I'm gunna need quite a bit more help than that.

Are you sure that dimethylpyrazine is supposed to smell like chocolate though? I looked it up on Sigma-Aldrich & it lists it's organoleptic properties are 'meaty, woody, nutty, & medicinal'. If I hop on wikipedia, and look at aromatic compounds it lists 4-Anisaldehyde as chocolate smelling.

------------
On a side note I spent much longer than I should have tracking down the scent & flavor for watermelon. It was surprisingly difficult for whatever reason.
cis,cis-3,6-nonadienal is the believed culprit. Here is an .pdf on this elusive compound.
https://www.ideals.illinois.edu/bitstream/handle/2142/16898/...

-----------
Here is a .pdfon the synthesis of n-hexylacetate which has an apple, floral, fruity aroma


[Edited on 9-7-2013 by Hockeydemon]

Random - 9-7-2013 at 08:09

2,5-dimethylpyrazine should smell like chocolate as its listed here

http://www.leffingwell.com/pyrazine.htm

It has low odor threshold so only one way to find out is to synthesize it. But it is true, I have seen various smells that descibe it, one of it is also fried potatoes?

2-isobutyl−3,5−dimethyl pyrazine is also listed on goodscentscompany as chocolate smelling compound but it would be probably harder to synthesize.


I believe watermelon flavor is hard to locare because there isn't one single compound. Have you ever tasted watermelon flavored candies or bubblegums? The taste was nothing like watermelon.

[Edited on 9-7-2013 by Random]

Waffles SS - 10-7-2013 at 22:45
Quote:

2,5-Dimethylpyrazine: Acetone oxime (17.4 g, 0.2 mole) was added in small portions
to a mixture of stannous chloride (90 g, 0.4 mole) and conc. HCI (130 ml). The reaction
flask was cooled with iced water, and water (200 ml), NaOH (25%, 380 ml), and ammonium
persulfate (64 g, 0.28 mole) were added in turn. After standing for 2 h it was steam distilled
to give 250 ml of distillate which was extracted with methylene chloride (4 x 150 ml).
The extracts were dried (anhydrous sodium sulfate) and evaporated in vacuo. Distillation
at normal pressure gave a fraction boiling at 153-156c (lit. bp 153.5-155c). Yield
6.65 g (56%). PMR Spectrum (CDCI3, TMS): 2.50 (s, 6H, CH3), 8.25 ppm (s, 2H, ring
protons). Mass spectrum, m/z (peak intensity, %): 108 (M +, 60), 81 (12), 42 (i00), 41
(27).
Synthesis and catalytic oxidation of 2,5-dimethylpyrazine



[Edited on 11-7-2013 by Waffles SS]

skeletal-clown - 11-7-2013 at 22:27

Quote: Originally posted by madscientist  
Cadaverine butyrate - roses.


Sounds.....wonderful >;D

Waffles SS - 14-7-2013 at 07:07

Somebody has experience on making Methyl anthranilate?(grape smell)
(Anthranilic acid is amino acid and it should has different route for esterification)


Esterification of PhenylAlanine
Quote:

methyl L-phenylalaninate

36 g of 98% sulfuric acid was added to a suspension of 33.1 g of L-phenylalanine in 60 g of methanol, and a reaction was carried out at 40°-50° C. for 7 hours. The reaction mixture contained 34.6 g of methyl L-phenylalaninate and 1.2 g of unreacted L-phenylalanine. Thereinto was fed 70 g of 1,2-dichloroethane, and about 220 g of a 8% water solution of sodium hydroxide was dropwise added in 1.5 hours with stirring at 20°-25° C. Successively, stirring and extraction were carried out for 0.5 hour while the pH of the aqueous layer was kept at 7.5. The organic layer was separated from the aqueous layer. The organic layer contained 29.4 g (percent extraction=85%) of methyl L-phenylalaninate, and the aqueous layer contained 4.8 g of methyl L-phenylalaninate and 1.6 g of L-phenylalanine. Therefore, the percent hydrolysis of methyl L-phenylalaninate during extraction was only 1.2%.

70 g of 1,2-dichloroethane was added to the aqueous layer. Thereto was dropwise added a 8% water solution of sodium hydroxide in 10 minutes with stirring. Successively, stirring and second extraction were carried out for 0.5 hour while the pH of the aqueous layer was kept at 7.5. The organic layer was separated from the aqueous layer. The organic layer contained 4.0 g (percent extraction=83%) of methyl L-phenylalaninate, and the aqueous layer contained 0.75 g of methyl L-phenylalaninate and 1.65 g of L-phenylalanine.

The aqueous layer after the second extraction was subjected to the same procedure as in the second extraction, to carry out a third extraction. The organic layer contained 0.62 g (percent extraction=83%) of methyl L-phenylalaninate, and the aqueous layer contained 0.12 g of methyl L-phenylalaninate and 1.66 g of L-phenylalanine.

After the third extraction, the total organic layer contained 34.02 g (percent extraction=98%) of methyl L-phenylalaninate and the percent hydrolysis of methyl L-phenylalaninate was only 1.3%.

Method for extracting an amino acid ester from a hydrous solution of a mineral acid salt thereof
USPatent 5374765




[Edited on 14-7-2013 by Waffles SS]

Crowfjord - 15-7-2013 at 16:08

@Madscientist: that reminds me of a trick I played in high school chemistry, taking a bottle of butyric acid around to unsuspecting classmates, offering a smell saying "take a whiff, it smells like strawberries," then watching in amusement as they gagged.

Phenethyl alcohol is supposed to smell like roses, and be a component of them but I haven't got to smell it yet for myself. The same has been said of benzyl alcohol (good scents company), but I can't hardly detect any aroma from it. The smell is very faint to me.

Random - 15-7-2013 at 22:23

Quote: Originally posted by Crowfjord  
@Madscientist: that reminds me of a trick I played in high school chemistry, taking a bottle of butyric acid around to unsuspecting classmates, offering a smell saying "take a whiff, it smells like strawberries," then watching in amusement as they gagged.

Phenethyl alcohol is supposed to smell like roses, and be a component of them but I haven't got to smell it yet for myself. The same has been said of benzyl alcohol (good scents company), but I can't hardly detect any aroma from it. The smell is very faint to me.


Rose smell can be attributed greatly to beta-damascenone, beta-damascone, beta-ionone, and rose oxide (from wikia)

[Edited on 16-7-2013 by Random]

Hockeydemon - 22-7-2013 at 04:05

I can't find anything that says cadaverine butyrate is the smell of roses. I would very much like to know if there is a source for this. There is an ironic elegance (IMO) to the smell of roses being the chemical 'love child' of the smell of rotting flesh & vomit.

bfesser - 22-7-2013 at 05:20

<strong>madscientist</strong> was just being a smart ass. I doubt the <a href="https://en.wikipedia.org/wiki/Amide" target="_blank">amide</a> <img src="../scipics/_wiki.png" /> in question has ever even been synthesized, let alone occurring in nature.

Fantasma4500 - 22-7-2013 at 05:44

benzoic acid -- both as dissolved, wet solid and dry solid it has a very strange slightly sweet smell
when a dust is pushed into the air it feels similar to SO3 however, if not worse, had to walk away when i was pouring the finished dried powder into a container x_X

i suppose this could be whats in Lavendel
if so an interesting thing to do could be to extract benzoic acid from lavendel, just seems weird to me that theres benzoic acid in lavendel?

hydride_shift - 3-8-2013 at 19:36

Quote: Originally posted by Waffles SS  


Ethyl butyrate(Pineapple)
Ethyl Alcohol + Acetic acid

[Edited on 3-7-2013 by Waffles SS]


That makes ethyl acetate*, which has a sickly sweet smell (not a fan).
CH3CH2OH + CH3COOH ⇌ CH3COOCH2CH3 + H2O

Ethyl Butyrate via esterification of butyric acid with acetic acid.

Theres a few more nice smelling esters mentioned here
http://www.projectshum.org/Ester/

makes me wish i had access to a wider variety of alcohols .



*Unless you happen to be a resourceful prokaryote ;)
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1078850/


[Edited on 4-8-2013 by hydride_shift]

Waffles SS - 4-8-2013 at 06:12

@hydride_shift ,
Sorry.it seems i did mistake and wrote Acetic acid instead of butyric acid.it is just typing mistake.
thanks