Palladium/Lewis Acid Co-catalyzed Divergent Asymmetric Ring-Opening Reactions of Azabenzonorbornadienes with Alcohols

By fine tuning the combinations of chiral palladium catalysts and Lewis acids, both the additional and reductive asymmetric ring-opening reactions of azabenzonorbornadienes with alcohols were accomplished with good chemoselectivity, regioselectivity, and enantioselectivity. It was proven that the reductive ring-opening products were generated through a transfer-hydrogenation process with alcohols as hydrogen source.