Claude Frajerman

Action des organomagnesiens sur les alcools allyliques en presence de complexes du nickel: I. Synthese d'olefines

Abstract The reaction between Grignard reagents, RMgX (R  Me, Ph, PhCH 2 ), and allylic alcohols R′CHCHC(OH)(H)R′′, in the presence of catalytic amounts of (Ph 3P ) 2 NiCl 2 , leads to a mixture of olefins (R′CHCHC(R)(H)R′′ + R′C(R)(H)CHCHR′′). This reaction constitutes a route to compounds with a quaternary carbon atom attached to germinal vinyl and methyl groups; thus, 1-vinylcyclohexanol and MeMgBr afford 1-methyl-1-vinylcyclohexane as the major product. The catalytic cycle probably involves π-allyl complexes of nickel, and intermediates with NiMg bonds.