Organocoppers, amination

Scheme 2.30 Ring-opening reaction with organocopper reagents to form (E)-allyl 111 amines.

Addition of organocopper reagents to imine derivatives can readily afford functionalized amine derivatives. Three recent examples are shown below (Equations (129) and (130) Scheme 102).498,498a,498b In these cases, iminium ions are employed as an activated imine. 

Scheme 3.34. Alkylation or arylation of amines by treatment of organocopper reagents with amines [119].

Chiral aminals 1,4-dihydropyridine-3-carboxaldehydes.1 The chiral aminal 2 prepared from pyridine-3-carboxylaldehyde and (S,S)-12 reacts with organocopper reagents in the presence of methyl chloroformate to give almost exclusively products of 1,4-addition, as expected from reactions of the free aldehyde.3 No products of 1,2-addition are formed, but 1,6-adducts are minor products in some cases. The 1,4-adducts are formed in 82-93% de (R-configuration). Addition of butyl and ethyl groups is best effected with lithium cuprates, but addition of methyl, vinyl, or aryl groups is best effected with organomagnesium cuprates. Under these conditions,... 

Germon, C., Alexakis. A., and Normant, J. F Vinyl-copper derivatives. XII. Slcreospecific synthesis of allylic amines by aminomethy-lalion of organocopper agents. Tetrahedron Utt.. 3763. 1980. 

Attempts to induce asynunetry at an imine carbon using homochiral amines to form Schiff bases followed by 1,2-additions with organocopper reagents has not produced a viable method as yet. Yamamoto... 

For organocopper compounds, the objective is accomplished by using copper concentrations above 100 ppm in combination with compounds that preferably complex and/or decompose hydroperoxide (hydroperoxide decomposers are discussed in the next section). Examples of compounds that preferably complex and/or decompose hydroperoxide are primary, secondary and tertiary amines, dialkylselenides,... 

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