ALKYLATION OF GEM-DIBROMOCYCLOPROPANES WI TH 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 Mel 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 st ereochemistry was deduced by the reaction mechanism.