Copper-Catalyzed Synthesis of Stereodefined Cyclopropyl Bis(boronates) from Alkenes with CO as the C1 Source

A novel copper-catalyzed stereodefined procedure for the selective synthesis of cyclopropyl bis­(boronates) from terminal alkenes has been developed. Various aliphatic alkenes were transformed into the desired bis­(boronate ester)-substituted cyclopropanes in moderate to good yields. Synthetic transformations of the resulting cyclopropyl bis­(boronates) demonstrate their utility. A possible reaction mechanism is proposed.