Enantioselective 1,4-additions of ClMeAl(CHCHR) (R = alkyl, alkenyl, Ph) to cyclohexenones†
Abstract
Chloromethylvinyl alanes (E)-ClMeAl(CHCHR) prepared directly from terminal alkynes undergo 1,4-addition to cyclohexenone and 3-methylcyclohexenone in moderate to good yield (30–70%) and good to excellent stereoselectivity (80–98% ee) using readily available copper(I) sources and chiral ligands.