Recent advances in rhodium-catalyzed C(sp)-H (hetero)arylation.

Arylation is a common behaviour in organic synthesis for the construction of complex structures, especially the biaryls. Among those reported arylation procedures, transition-metal-catalyzed direct C(sp)-H arylation has been rapidly developed in recent decades and has become a reliable alternative to traditional cross-coupling procedures using organometallic reagents. Great achievements in rhodium-catalyzed C(sp)-H arylation have been witnessed during the last decade. Aryl halides, simple arenes, aryl boronic acids, arylsilanes, aryl aldehyde, aryl carboxylic acid, diazides, . were successfully utilized as arylating reagents under rhodium-catalyzed conditions. In this review, recent achievements in rhodium-catalyzed arylations through C(sp)-H bond activation were summarized together with the mechanism discussions.