The degenerative radical transfer of xanthates and related derivatives: An unusually powerful tool for the creation of carbon-carbon bonds

This review summarises recent work on the dithiocarbonyl group transfer reaction. Xanthates, in particular, have proved to be extremely useful for both inter- and intra-molecular additions. The broad applicability of the intermolecular addition to un-activated olefins opens tremendous opportunities for synthesis, since various functional groups can be brought together under mild conditions and complex structures can be rapidly assembled. The presence of the xanthate in the product is also a powerful asset for further modifications, by both radical and non-radical pathways. Of special importance is the access to highly substituted aromatic and heteroaromatic derivatives and the synthesis of block polymers through a controlled radical polymerisation mediated by various dithiocarbonyl agents (RAFT and MADIX processes).