Amino acid decarboxylation, need Chem Lett article

[Cyrax]

Before taking a nap, I read some in the advanced organic chemistry from our dear friend Jerry March.  It seems that 2-cyclohexenone is used in a catalytic amound to decarboxylate alpha-amino acids (p. 629).

Could some friendly bee get his / her hands on the Chem. Lett. (1986) p. 893 article and type in the lab procedure.  A .PDF file would be even better.  I think they use the decarboxylation of Phe as an example.

[Rhodium]

20 grams of L-Tryptophan was dissolved in 150 ml cyclohexanol containing 1.5 ml of 2-cyclohexen-1-one, and the temp of the solution was held at 154°C for 1.5 hours. The tryptamine was isolated as the HCl salt, mp 256°C. Yield 92.3%.

Ref: M. Hashimoto, Decarboxylation of Amino Acids with 2-cyclohexanone,

Chem. Lett. 893 (1986)

(https://www.thevespiary.org/rhodium/Rhodium/chemistry/trp.decarbox.enone.html)

[pHarmacist]

Excellent find Rhodium.
pHarmacist

[java]

Êsee.ÊÊPost  at  Wanted References at Methods Forum
Java:
Decarboxolation of Amino AcidsÊ was made available to me by chimimanie, I hence converted it to PDF and have it available . As for the Photodecarboxalation that too was also provided but its not converted to PDF its in a gif format, will convert to a PDF soon..........java
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[urushibara]

[hypo]

what is your point?

[urushibara]

my main point here is that decarboxylating carboxylic acid groups is most certainly catalysed by ketones - it is well documented.

Further to that is that for lack of neccessity, decarboxylation has not been thoroughly studied by mainstream chemists. carboxylic acids, in particular amino acids, can be, in some cases, made useful to clandestine chemists via carboxylation (tryptamine is basically it though there might be other uses). Regular chemists can usually synthsise using chemicals made industrially and purified. they don't look for otc sources or reaction systems.

and to repeat my first point - cyclohexanol/2-cyclohexen-1-one decarboxylation of tryptophan, in particular, has been posted on rhodium's site for at least a year as far as I know. In fact it's gotta be older because krz's dmt synth is older than a year and was posted after the decarb tek.

student had a go at using turpene media and carvone (major component of spearming and ketone) with limited success.

urushibara (me) once did silly things with high pressure/temperature and acetone, and seemed to result in some decarboxylation of amino acids (lysine and tyrosine) extracted via ethanol from amino acid supplements. certainly the strong smell and gooey character of at least 50% of the results suggested that.

I don't know how clean the results were though.

it seems nobody has got the balls to replicate it. I suspect that 250 was too high and caused some oxidation of the resultant alkaloid freebases. lower temperatures and longer reactions might turn out to be useful.