AMT-help !!

brain · Linguist Extraordinaire

i used gramine, 1-nitropropan, and on this step i stopped-because my autoclaw is broken !! and i thin i cant rescue it from trowing on junk-yard Sad

... and what can i du with it? Al/Hg ??? i will be glad eawen with 5% yeld Sad

!!! help... dont hawe eaven ranier Ni at the moment - my w6 oxidates -with air Sad

... help ...

IndoleAmine · Dreamreader Deluxe

You mean you tried a henry rxn with gramine and 1-nitropropane? Doesn't work, you need an aldehyde (or ketone too?) for that, tertiary amines like gramine don't condense with nitroalkanes under henry conditions!

You need indole-3-carboxaldehyde in order to make the corresponding indolyl-nitrostyrene, which then gives AMT upon reduction...

cheers

i_a

Sandmeyer · Mon Apr 25, 2005 3:49 pm

IndoleAmine · Dreamreader Deluxe

Sandmeyer: If you use the sentence "Stop spreading missinformation" one more time, you'll regret it.

Its ok that you post just to correct my personal errors, if you feel appointed to act as my personal proffreader, thats fine - but this is not the way of telling someone that he has made an error; you impute that the person you're adressing does give false information intentionally.

Since this is absolutely NOT the case, using this terminology just leads to bad temper and therefore I herewith officially and urgently request you to use other, common terms like "you're wrong" or "its not exactly like that" or whatever from now on.

Just stop using insultive terminology, and you suddely will appear alot friendlier.
Which is urgently necessary IMO..

And besides that: I didn't "spread any misinformation": I said that henry rxns don't work with tertiary amines like gramine as reactands, said that you'd need to "knoevenagel" condense indole-3-carboxaldehyde with nitroethane and reduce the obtained nitrostyrene to get AMT.

Now tell me what is wrong with that?
(remember <10% yield with gramine alkylation of nitropropane vs. >40% yield with henry rxn between indol-3-yl-carboxaldehyde and nitroethane!!)

And citing an inferior procedure copied from the same document where the superior procedure can be found too is a REALLY bad way of trying to start arguing about them - dumbass.

And BTW: this threads name is "AMT - help!" not "AET - help!", so you're rather off-topic with your post..

Sandmeyer · Tue Apr 26, 2005 2:46 am

I just did some search, check out this paper: Somei, Masanori; Karasawa, Yoshio; Kaneko, Chikara; Heterocycles; 16; 6; 1981; 941-949.

They alkylate a number of nitroalkanes with gramine, for the nitro precursor of AMT the yield is 70%.

Indeed, there is a paper detailing the preparation of a,a-dimethyltryptamine from gramine (alkylation-promoting base being NaOH): J. Med. Chem.; 23; 3; 1980; 285-289, alkylation-yield being a bit lower: 70%.

For more on gramine/nitroalkane see: J . Org. Chem., Vol. 55, No. 13, 1990 and references there, particulary Cohen, A.; Heath-Brown, B. J . Chem. Soc. 1965, 7179. What is intersting in the JOC paper is that they get the N-hydroxylamine when using Al/Hg on nitroalkane:

To a stirred solution of 5-Methoxy-3-(2-nitroethyl)indole (9 g, 41 mmol) in EtOAc (saturated with water) was added freshly prepared Al(Hg) (Fieser and Fieser, vol. 1, p 20) portionwise. After completion of the reaction (5 h) as was monitored by TLC (CHCl3/MeOH, 93/7, v/v), the reaction mixture was filtered, the residue was dried (MgSO4), and the solvent was evaporated in vacuo. The residue was crystallized from EtOAc n-hexane to give 7.83 g (93%) of 5-Methoxy-3-[2-(hydroxyamino)ethyl]indole.

IndoleAmine · Dreamreader Deluxe