THE EFFECT OF SOLVENT AND COPPER(I) PRECURSOR ON THE REGIOSELECTIVITYIN THE CROSS-COUPLING REACTION OF PRIMARY ALLYLIC ACETATES WITH PREFORMED MONOBUTYLCUPRATES AND DIBUTYLCUPRATES

The reactions between preformed organocopper compounds and primary all ylic acetates show that the solvent and the copper(I) precursor are im portant parameters in determining the regioselectivity of the reaction . The organocopper complexes were prepared from different copper(I) sa lts, such as CuCl, CuBr, CuI and CuCN, and their reactivity both in Et (2)O and THF were studied. In THF, monobutylcuprates gave the gamma-su bstituted product whereas the dibutylcuprates afforded the alpha-subst ituted product. In Et(2)O, cuprates formed from CuCN and CuI gave gamm a-selective reactions whereas those from CuCl and CuBr resulted in alp ha-selective reactions.