Tryptophan to tryptamine: practical xperiences

[yellium]

Napthalene will dissolve pretty good in DCM. And you certainly don't want to add DCM to a more than hand-warm water solution.

(been there, done that, decorated the ceiling again.)

[superhybrid]

Beilstein says that it can be done in diphenyl ether to 63% yields. It simply said tryptophan was heated for 10 hours in diphenyl ether(I would assume under reflux). Maybe if they refluxed longer yields would have been higher???

With the above reaction one can seperate the two recover the tryptophan and do it again seperate recover and do it again etc....{The point is that the use of a ketone was not used so it isn't always needed aparently} Polyethylene glycol is a polyether with alcoholic ends. Might work, might not. CHeck er, out!

With a simple column you should be able to seperate these two quite easily(tryptophan from tryptamine). I also did not find much on the use of ethylacetate to do the seperation. That could prove to be quite useful also. On one hand the decarboxylated product could be much more soluble in the EtOAc than the carboxylated precurser.

Diphenyl ether has a very electron poor Oxygen linkage though which could be better than a glycolic polyether in this reaction.

Sorry best I can do!

[halfapint]

PEG, yeah, just what I was thinking. With fewer hydroxyls, it won't bump into Lilienthal's objection as badly as glycol, or say, glycerine would. Naphthalene, hm, who knows -- with this "solvent", how could you ever get your Tryp out? Sounds like you're in a worse fix than with DMSO! Any way a vegetable cooking oil could dissolve tryptophan? Aqueous acid would sure pull the basic tryptamine out of that, a lot easier than it would the amphoteric amino acid. But for a catalyst, try benzoquinone! Betcha that would work.

Turning science fact into <<science fiction>>

[foxy2]

Naphthalene shouldn't be so hard to remove.  An A/B at 90°C should be all liquid and remove most of the naphthalene.  The remainder can be easily washed out with DCM(of course not at 90°C).



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[Lilienthal]

You don't have to heat for the acid / base extraction if you use an organic solvent  

[foxy2]

Lili
The melting point of naphthalene is approximately 80°C so doing the initial acidic water extraction at 90°C will bee necessary.

Do Your Part To Win The War

[Lilienthal]

Use an organic solvent during the acidic extraction. Naphtalene will stay in the organic phase, the tryptamine salt moves into the aqueous phase.

[foxy2]

Yea ok as usual someone comes along with a better method
Thanks Lili


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[Maighstir]

psychokitty> "According to Drone, acetone, DMSO and tryptophan, when heated together, provides tryptamine in good yield.  I KNOW I have the Old Hive thread in which he states this printed out somewhere and as soon as I find it, I'll post the details."

So, does this method work or not? I got a bit lost in all the comments. I need to make some tryptamine soon.

Maighstir.
Vae victis meretrix est et mors venit.

[Lilienthal]

My (purely theoretic) guess is that it may work under absolutely anhydrous conditions with removing the water formed during imine formation. Then (and only then) it wouldn't matter if all your acetone boils off after a few minutes of heating.

But I would simply use a much higher boiling ketone.

[terbium]

Rhodium just recently posted in this Forum a very promising looking method using copper ion to promote the decarboxylation.

Post 211603

(Rhodium: "Another tryptophan decarboxylation", Tryptamine Chemistry)

[foxy2]

Try THUJONE as the ketone, just get some high thujone wormwood essential oil.  I think it might work.

THUJONE

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[IudexK2]

artemisia absinthium is around 50% thujone
thuja plicata essential oil is around 90% thujone

[Ritter]

The DMSO/copper chelate decarboxylation works like a charm with phenylalanine.  SWIM has found that yields are in the 70% range with this amino acid.  Unlike my cyclohexanone/cyclohexanol decarboxylation archived at Rhodiums site, this procedure produces repeatable yields.

Make sure decarboxylation is carried out in a hood as DMSO vapors are horrible!

[element109]

Ritter, do the yields of your reaction fluctuate? I always thought it was a high-hitter (80+%), and the DMSO reaction gives only 40% yield.

First i wanted to try the DMSO reaction, but comparing the prices of DMSO and cyclohexanol, think SWIM's going to try a chelate in cyclohexanol reaction, next month or so.
It's always good to try a new idea, isn't it?


e109