Asymmetric Desymmetrization and Kinetic Resolution of 1,2-Diols

Significance

Prior to this work only two examples of semi-catalytic asymmetric oxidation of 1,2-diols using chiral dioxiranes and hypervalent iodine had been reported (K. Jakka, C.-G. Zhao Org. Lett. 2006, 8, 3013; U. Ladziata et al. Tetrahedron Lett. 2006, 47, 6301). This paper reports the first truly catalytic asymmetric oxidation of 1,2-diols promoted by NBS in the presence of a copper catalyst. Desymmetrization of meso-hydrobenzoin gave the α-keto alcohol in moderate yield and ee. Additionally, kinetic resolution of diols 5 could be achieved to produce enantioenriched 1,2-diols in moderate yields and with low enantioselectivity.