Enantioselective conjugate addition to cyclic enones with scalemic lithium organo(amido)cuprates, part IV. Relationship between ligand structure and enantioselectivity

Article abstract of DOI:10.1016/S0040-4020(01)86278-5

Scalemic lithium amides derived from primary and secondary amines react with organocopper compounds in ether or dimethyl sulfide to form lithium organo(amido)cuprates capable of enantioselective conjugate addition to 2-cycloalkenones. The most successful heterocuprate, in which the chiral ligand is (S)-N-methyl-1-phenyl-2-(1-piperidinyl)ethanamine, (S)-MAPP, 13, reacts with cyclic enones to form products with up to 97% ee. Nonlinear asymmetric induction was observed with the cuprate formed from ligand 13.