Catalytic asymmetric bromine-lithium exchange: A new tool to build axial chirality

Abstract

We present here the first catalytic desymmetrization of the 2,2′,6,6′-tetrabromobiphenyl 1 and analogues, by a bromine-lithium exchange catalyzed by either diamines or diether derivatives (0.5 equiv.), yielding axially chiral compounds in high yield (up to 89%) and high enantioselectivity (up to 82%). © 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.