Iron/N-doped graphene nano-structured catalysts for general cyclopropanation of olefins

The first examples of heterogeneous Fe-catalysed cyclopropanation reactions are presented. Pyrolysis of in situ -generated iron/phenanthroline complexes in the presence of a carbonaceous material leads to specific supported nanosized iron particles, which are effective catalysts for carbene transfer reactions. Using olefins as substrates, cyclopropanes are obtained in high yields and moderate diastereoselectivities. The developed protocol is scalable and the activity of the recycled catalyst after deactivation can be effectively restored using an oxidative reactivation protocol under mild conditions. An Fe-based heterogeneous catalyst allows for the synthesis of cyclopropanes via a carbene transfer reaction, a transformation usually belonging to the homogeneous domain.