Captain_Mission
(Stranger / Eraser)
01-05-03 02:07
No 395481
      lithiation of nitrosamines idea/question
(Rated as: good idea!)
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Recently I was having some fun by reading http://www.orgsyn.org/orgsyn/prep.asp?prep=cv6p0542 , linked from ../rhodium/chemistry /pyrrolidinyl.html.
I you scroll down to the discussion and have a look at the table you will see a number of examples were benzaldehydes and a benzyl bromide are reacted with various lithiated nitrosamines, yielding, in the case of the benzaldehydes, N-substituted alpha-hydroxyphenethylamines and, of benzyl bromide a N-substituted phenethylamine.

One of the most interesting reactions is where benzaldehyde is reacted with the lithiated nitroso-diethylamine, to give n-ethyl ephedrine.
Well, it looks to me that if one were to use benzyl bromide or piperonyl bromide  in that reaction the product would be the n-ethylamphetamine.

Now, What I want to ask you people is: what if methylethylamine is used? Will the lithium atom attatch itself to the methyl or to the alpha carbon of the ethyl chain.
I guess you can see where I am getting at.

 
 
 
 
    Rhodium
(Chief Bee)
01-05-03 03:36
No 395506
      At thermodynamical equilibrium, the lithiation  Bookmark   

At thermodynamical equilibrium, the lithiation should preferentially take place at the alpha-position of the N-ethyl chain. Being secondary, the hydrogens in that position should be significantly more acidic than on the N-methyl.