Catalyst-controlled enantioselective 1,1-arylboration of unactivated olefins

Abstract

Enantioselective difunctionalization of alkenes constitutes an efficient strategy to assemble complex chiral molecules from simple racemic or achiral starting materials. Here we present an intermolecular nickel-catalysed enantioselective 1,1-arylboration of unactivated terminal alkenes. The high regio- and enantioselectivities of the reactions arise from a judicious choice of the nickel catalyst rather than the incorporation of a directing group. Moreover, excellent regioselectivities can also be obtained from the reactions of allylbenzenes. We also conducted a series of stereospecific downstream transformations for the enantioenriched secondary boronic esters. These examples represent an efficient catalyst-controlled enantioselective 1,1-difunctionalization of unactivated alkenes. Difunctionalization of alkenes can afford useful building blocks from readily available starting materials, but these reactions often show limitations in olefin scope. This work presents a catalyst-controlled enantioselective 1,1-arylboration of unactivated alkenes that is independent of directing groups.