[Alkylation of gem-dibromocyclopropanes with higher-order organocuprates]

The reaction of gem-dibromocyclopropanes (1) with a higher-order organ-ocuprate prepared from CuCN and commercially available MeLi, followed by the addition of MeI in situ, afforded dimethylcyclopropanes (2) in good yields. The differential substitution reaction of dibromide (1a) in one pot with the higher-order organocuprate and allyl bromide gave a compound (8) in the moderate selectivity as shown in Table 3. Its stereochemistry was deduced by the reaction mechanism.