Complementary Catalytic Strategies to Access ?-Chiral Aldehydes

The present article summarizes the development of two novel and complementary catalytic methods to access alpha-chiral aldehydes. A C1-symmetric chiral (P,N) ligand with a structure derived from the ubiquitous binepine scaffold has been specifically designed for the Pd-catalyzed alpha-arylation of aldehydes to access indane derivatives with a well-defined quaternary stereocenter in high yields and excellent enantioselectivities. In addition, a dinuclear palladium hydride catalyst has been synthesized for the isomerization of terminal and trisubstituted epoxides into aldehydes and ketones respectively. Combined experimental and theoretical investigations pointed to an unprecedented 'epoxide-opening/hydride-transfer' sequence. The mechanism also features two distinct enantio-determining steps in the kinetic resolution of racemic epoxides.