Pd-Catalyzed Enantioselective Aerobic Oxidation of Secondary Alcohols: Applications to the Total Synthesis of Alkaloids

Enantioselective syntheses of the alkaloids (−)-aurantioclavine, (+)-amurensinine, (−)-lobeline, and (−)- and (+)-sedamine are described. The syntheses demonstrate the effectiveness of the Pd-catalyzed asymmetric oxidation of secondary alcohols in diverse contexts and the ability of this methodology to set the absolute configuration of multiple stereocenters in a single operation. The utility of an aryne C−C insertion reaction in accessing complex polycyclic frameworks is also described.