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Waffles SS
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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
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[Edited on 11-7-2013 by Waffles SS]
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skeletal-clown
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Sounds.....wonderful >;D
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Waffles SS
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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
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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
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[Edited on 14-7-2013 by Waffles SS]
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Crowfjord
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@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.
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Random
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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]
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Hockeydemon
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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.
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bfesser
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<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.
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Fantasma4500
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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?
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hydride_shift
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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]
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Waffles SS
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@hydride_shift ,
Sorry.it seems i did mistake and wrote Acetic acid instead of butyric acid.it is just typing mistake.
thanks
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bfesser
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Thread Moved 11-8-2013 at 07:57 |
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