Author Topic: DPT purification issues...  (Read 1624 times)

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Bandil

  • Guest
DPT purification issues...
« on: December 19, 2002, 03:14:00 PM »
Swim has worked on some DPT and DiPT again today, but has encountered some problems...

8 grammes of tryptamine was dissolved in 50 mL's of IPA together with 25,5 g prpyliodide and 26 grammes diisopropylethylamine. This was heated on a water bath for some hours and then left with stirring for 48 hours.

A lot of white crystals precitipated during this time.

A lot of 10% NaOH was added and the soln was extracted with 3X chloroform. The solvent was stripped and the DPT was attempted vacuum distilled, but the vacuum was not strong enough to pull the tryptamine over, so the chloroform was dried with sodiumsulfate and gassed with anh. HCl gas. Nothing fell out...

The Chloroform phase was then extracted three times w. acidic water and the extracted into a DCM phase(the pH shifts all gave nice white clouds of tryptamine...). This was dried with sodium sulfate and gassed again. This time huge clouds fell out but after a short while the dissapeared and left the soln. red/clear again???

anyone knows what happened here? Why did the tryptamine fall out and then redissolve?? The DCM phase is now left out in the cold to think about how i behaved!!

Swim would like to have the crystalline DPT before he continues with the DiPT that is currently bubling :)

Thanks!!

Regards
Bandil

Rhodium

  • Guest
I would suggest you try gassing the dry freebase ...
« Reply #1 on: December 19, 2002, 03:32:00 PM »
I would suggest you try gassing the dry freebase in anhydrous ether instead (as directed in Tihkal), and if that does not work, I'm afraid that you need to flash chromatograph your product before it becomes pure enough to crystallize.

Bandil

  • Guest
OK, guess ill try it this weekend then, but how ...
« Reply #2 on: December 20, 2002, 05:33:00 AM »
OK, guess ill try it this weekend then, but how come the DPT crystallized in the soln. and the dissolved after ½ min? Thats quite odd...

Rhodium

  • Guest
No, that's relatively common with impure ...
« Reply #3 on: December 20, 2002, 06:21:00 AM »
No, that's relatively common with impure freebases and/or if you use a sub-optimal solvent or use too much acid.