N,N- and N,O-Bidentate-Chelation-Assisted Alkenyl C-H Functionalization.

Chelation-assisted olefinic C-H functionalization has been demonstrated to be a powerful method of constructing multi-substituted alkenes from simpler ones. This strategy produces complex alkenes in a regio- and stereoselective manner, followed by C-H endo- and exo-cyclometallation. Among the various directing groups developed, N,N- and N,O-bidentate directing groups are the most widely used to selectively promote C-H functionalization due to their fine, tunable, and reversible coordination with the metal center.

Synthesis of silyl indenes by ruthenium-catalyzed aldehyde- and acylsilane-enabled C-H alkylation/cyclization.

A ruthenium-catalyzed C-H alkylation/cyclization sequence is presented to prepare silyl indenes with atom and step-economy. This domino reaction is triggered by acyl silane-directed C-H activation, and an aldehyde controlled the following enol cyclization/condensation other than β-H elimination. The protocol tolerates a broad substitution pattern, and the further synthetic elaboration of silyl indenes allows access to a diverse range of interesting indene and indanone derivatives.