Ru(II)-catalyzed ortho-amidation and decarboxylation of aromatic acids: a versatile route to meta-substituted N-aryl benzamides

Carboxylate as a promising and valuable directing group has attracted a great deal of attention. However, employing it as a traceless direction group has rarely been reported. We developed the ruthenium-catalyzed amidation of substituted benzoic acids with isocyanates via directed C-H functionalization followed by decarboxylation to afford the corresponding meta-substituted N-aryl benzamides, in which the carboxylate serves as a unique, removable directing group. Notably, this protocol can provide an efficient alternative to access meta-substituted N-aryl benzamides, which are much more difficult to prepare than ortho-substituted analogues.