Enantioselective Allylic C−H Oxidation of Terminal Olefins to Isochromans by Palladium(II)/Chiral Sulfoxide Catalysis

The enantioselective synthesis of isochroman motifs has been accomplished by palladium(II)‐catalyzed allylic C−H oxidation from terminal olefin precursors. Critical to the success of this goal was the development and utilization of a novel chiral aryl sulfoxide‐oxazoline (ArSOX) ligand. The allylic C−H oxidation reaction proceeds with the broadest scope and highest levels of asymmetric induction reported to date (avg. 92 % ee, 13 examples with greater than 90 % ee). Selective and general: Palladium(II)/chiral sulfoxide catalysis affords an asymmetric allylic C−H oxidation reaction which proceeds with broad scope and high levels of enantioselectivity. The palladium(II)/ArSOX catalyst furnishes chiral isochromans from terminal olefin precursors and the reactions are run open to the air and moisture.