Catalytic, Asymmetric Halofunctionalization of Alkenes-A Critical Perspective

Despite the fact that halogenation of alkenes has been known for centuries, enantioselective variants of this reaction have only recently been developed. In the past three years, catalytic enantioselective versions of halofunctionalizations with the four common halogens have appeared and although important breakthroughs, they represent just the very beginnings of a nascent field. This Minireview provides a critical analysis of the challenges that accompany the development of general and highly enantioselective halofunctionalization reactions. Moreover, the focus herein, diverges from previous reviews of the field by identifying the various modes of catalysis and the different strategies implemented for asymmetric induction. The return of the salt makers: Catalytic enantioselective versions of halofunctionalizations have recently appeared and although important breakthroughs, they represent just the very beginnings of a nascent field. Herein is a critical analysis of the challenges that accompany the development of general and highly enantioselective halofunctionalizations. Various modes of catalysis and the different strategies implemented for asymmetric induction are identified. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.