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The first catalytic, enantioselective syntheses of quinine and quinidine is described. Asymmetric catalyst-based synthesis opens the possibility of accessing diastereomeric products with the help of a common route.

X-ray and kinetic studies probe into the origin of high enantioselectivity in the Sharpless asymmetric dihydroxylation of chiral olefins. Notwithstanding contrary evidence from the crystal structure of an OsO4-ligand complex, kinetic experiments strongly suggest a mechanism in which the stereofacial attack proceeds through a mu-oxo-bridged bisosmium(VIII) species where the dihydroquinine ether ligand is bonded to the hexacoordinate Os via the bridgehead nitrogen of its bicycloazaoctane arms.