Copper-catalysed kinetic resolution of cyclic alkenyl cyclopropane malonates with organoaluminium and Grignard reagents

We report herein the first copper-catalysed kinetic resolution of alkenyl cyclopropane malonates with organoaluminium and Grignard reagents. The conjugate products were exclusively obtained on five- and six-membered-ring substrates. After optimization of the reaction conditions, we observed good conversions and enantiomeric excesses using ferrocene-based ligands on five-membered-ring substrates, and phosphoramidite ligands on six-membered rings.