Helical chiral pyridine N-oxides: a new family of asymmetric catalysts.

Optically active chiral alkyl chlorides are valuable compounds because of their bioactivity and versatile synthetic utility. Accordingly, the ring opening of epoxides with a chloride nucleophile stands as an important goal in asymmetric catalysis. We describe herein recent advances in the design and development of chiral pyridine N-oxide catalysts for the enantioselective synthesis of chlorohydrins.