Unlocking Stereodefined Olefins by Z-Selective Transition Metals-catalyzed C−H Activations

Z-olefins are key synthetic intermediates in organic chemistry, and they are ubiquitous functionalities since they are present in many pharmaceuticals, biologically relevant compounds, and materials. Recently, several catalytic strategies for the non-trivial synthesis of these compounds have been reported to overcome the limitations linked to the use of stoichiometric reagents. Among these methods, the direct C−H functionalization of (hetero)arenes represents a complementary yet challenging strategy. Within this review, we aim to discuss the stereoselective synthesis of olefins by Z-selective transition metals-catalyzed C−H activations. In particular, we will focus on the design of novel methods for the synthesis of Z-alkenes, characterized by a single double bond, and (E,Z)-1,3-dienes. The origin of Z-stereoselectivity and late-stage derivatizations for the synthesis of value-added derivatives will be further discussed to provide a complete overview of this innovative approach in the field of synthetic methodologies.