I looked, but did not find.
In one version of tryptamine synthesis, oxalyl chloride is condensed with indole, then the stuff alkylates some amine to give this (I don't know what it's called)
Molecule: (https://www.the-hive.ws/forum/faq.pl?Cat=#applet)
intermediate ("c1nc2ccccc2c1C(=O)C(=O)N(C)C")
Which is then reduced with LiAlH4, usually. Every reaction on beilstein does this. Maybee some bee has used the clemenson reduction also, I do not know.
What I would like to know is whether a Wolff-Kishner reaction would remove those carbonyls, or reaction conditions would destroy the tryptamine. (Pictet-Spengler, Lili? 8) Or something?)
I guess if acidic conditions cause that, it would be a strike against the Clemenson. But Wolff-Kishner is basic. Any threads here on this matter already? UTFSE again?
The carbonyl closest to the ring (the aromatic carbonyl) shouldn't be a problem to reduce with any of the regular methods for reducing them. I don't know what would happen with the amide though. But I suspect it would survive since they tend to be tough bastards. The amide can then be reduced to the amine with e.g. sodium triacetoxyborohydride (which can be found in TFSE).
The intermediate is a N,N-disubstituted indolyl-3-glyoxylamide
I don't know what would happen with the amide though. But I suspect it would survive since they tend to be tough bastards.
Survive the conditions for the Wolf-Kishner? Like >150°C, KOH and hydrazine in glycol? No way. This bastards are not that tough.
Bah! I'd take a Wolff-Kishner any day of the week. ;)
On second thought, you might have point there. How about the Clemmensen then?
I guess there are possibilities for the amide to come out of the Clemmensen more or less intact, but this reduction is known to sometimes cause impredictable results with substrates that are more than just plain ketones (have other functions as well). Besides I don't even know if it works for beta-keto-amides. The indole group can also bee cause for many unpredictabilities (just think of the NaBH4 reduction of 3-acethyl-indoles). And then, what should be done with the amide group? Just don't say LiAlH4 please.
Edit: The best thing to try out would bee a NaBH4 reduction of both the amide and the keto group like in
https://www.thevespiary.org/rhodium/Rhodium/clandestine/dmt/index.html (https://www.thevespiary.org/rhodium/Rhodium/clandestine/dmt/index.html)
but in the presence of a catalyst that enables the borohydride to reduce amides (maybe NiCl2?).
Nicodem, you obviously did not read the entire post I made above. Use STAB for the amide.
Sorry. :-[
However, a two step reaction is not tempting at all.
What, do you think of a one step alternative, something cleaner than Clemmensen? Hey, I think your STAB should do just well for both keto groups.
Searched beilstein a little more carefully, and I found two types of reactions.
In the first case, indole-CH2CH2COOMe + N2H4 --> indole-CH2CH2CONHNH2
In the second case, yohimbine (which contains the tryptamine core) is treated to the wolff-kishner.
I don't know if this is of use, but it is suggestive that tryptamines MIGHT survive.