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Leuckart reaction

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gandalf:
Hello it always tries Leuckart with exito but it makes threea attempts that it come failing; somebody know as it is the correct temperature, and the correct conditions of hidrolisis of amide; I warm up around 190 centigrados degrees ah this temperature the reaction reaches ebb tide, five to six hours, the mixture is darkened, it is put brown and black finally; it is too much heat?
thank for his answers.

terbium:
180-190°C would probably be about the correct temperature if you were making methamphetamine. I have used this before for methamphetamine, the yields are low, only 30-40% and a lot of black junk is formed. I don't know how well this will work for MDMA, the methylenedioxy ring may be destroyed under these conditions. Some people say that the yields should be higher when the Leuckart is used with formamide to prepare amphetamine but again I wonder about the stability of the methylenedioxy ring when trying to use this method to prepare MDA.

methlab:
Hi! I would like to make some MDA via the leuckart reaction.
Therefore i wanted to make some formamide (or ammonium formate), which should also work. I added 25% ammonia to 86% formic acid until ph > 8 to neutralize the acid. Then i setup for vacuum distillation to remove water. When all the water was gone the temp started to rise a little bit, but in between a couple of minutes about 98% of the solution solidified into a white crystal mass, just a little bit of 'something' was left.
Can one tell me, if i did something wrong? What should i do to get formamide, or can i use this white crystal mass? If yes, should i dissolve the crystals in something, or will they turn into a liquid when heated again? It sounds a little bit strange to me, to add my lovely ketone to this crystals and then cook everything until...
Thanx

methlab:
hi again. sory, i think i didn't search enough, i found a thread called 'Getting formamide from ammonia formate', which made everything clear (hopefully). will continue heating the white mass to about 180, until it stays a liquid, thanx.

ning:
I'm very interested in the leuckart (why? who knows)
Now I know you probably aren't so interested in doing research as getting amine, but here is a precious, lovely thread. Read it. Admire it. Love it.

Post 302161 (missing) (Antoncho: "Leuckart with 92%+ overall yield", Methods Discourse)

Second, I here must shamelessly plug my own thread -- a great idea of Tengo's that turned out to be much less wild than originally seemed.

Post 497428 (ning: "Oxalic acid leuckart reaction", Novel Discourse)

Now, this is the formaldehyde version of the leuckart. It's much easier than the normal one. However, it's a very likely thing that if it works for one, it will work for the other.

The leuckart is supposed to work best when the temperature is ramped up slowly and the reaction run for a while.

I recommend performing hydrolysis in-situ, as it will raise yields. Not all the reduced amine forms an N-formyl derivative, and if you isolate the N-formyl derivative, you throw that amine away.

So, read rhodium's page, search the hive a bit, and read those two links. Best of luck to you.

And *nudge nudge* if you do happen to have some extra ketone to play with, well, ning would be very interested to know how well ammonium oxalate amines ketones....suggested molar ratio ketone 1, ammonia 2, oxalic acid dihydrate 6, for starters.

Peace Bee.

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