Pd-catalyzed exclusively regioselective [5 + 4] cycloaddition for the construction of 1,5-di/ox-azonanes

Abstract

An efficient approach for the construction of 1,5-di/ox-azonanes via Pd-catalyzed [5 + 4] cycloaddition has been developed. This reaction could tolerate a variety of functional groups with exclusive regioselectivity, affording a series of nine-membered heterocycles in moderate to excellent yields. The synthetic utility of the current method was also demonstrated by a gram-scale reaction.