Steric and complexation effects on the 1,4-addition reaction of lithium dimethylcuprate with rigid α,β-unsaturated ketones

Article abstract of DOI:10.1016/S0040-4020(98)83052-4

Reaction of lithium dimethylcuprate with a series of substituted 10- methyl-l(9)-octal-2-ones in diethyl ether give 1,4-addition products with the same ring junction stereochemistry as the parent, unsubstituted α,β- unsaturated ketone. The reactivity of the system is modified by groups positioned axially and 1,3 with respect to the β-carbon of the enone. Alkoxy substituents are generally activating, particularly if they are syn with respect to the incoming methyl group.