[reaction: see text] Polyfunctional mixed lithium arylcuprates of the type (FG-Ar)(PhMe(2)CCH(2))CuLi obtained via iodine- or bromine-copper exchange with (PhMe(2)CCH(2))(2)CuLi react with cyclic 2-iodoallylic acetates with high S(N)2 selectivity. The addition of ZnBr(2) changes this selectivity and allows the performance of highly regioselective and enantioselective anti S(N)2' substitutions using