CN bond formation via palladium-catalyzed carbene insertion into NN bonds: inhibiting the general 1,2-migration process of ylide intermediates

Abstract

A new example of C[double bond, length as m-dash]N double bond formation in metal carbene insertion reactions is reported. Remarkably, the general 1,2-migration process of the corresponding ylide intermediates in X-H carbene insertion reactions that leads to C-X single bond formation is completely inhibited by replacing the H atom with a nitrogen atom. This palladium-catalyzed carbene insertion reaction with N[double bond, length as m-dash]N double bonds gave various N,N-disubstituted hydrazone products in high yields.