Rh(III)-catalyzed C-H activation/[4+3] cycloaddition of benzamides and vinylcarbenoids: facile synthesis of azepinones

Vinylcarbenoids are used as three-carbon components in Rh(III)-catalyzed C-H activation/[4 + 3] cycloaddition with benzamides to access azepinones. This transformation makes a feature of simple starting materials, mild reaction conditions and high efficiency. A kinetic isotope effect study was conducted and a plausible mechanism is proposed.