Merging Photoredox/ <scp> CO ₂ </scp> ^•− Catalysis: Regioselective Hydroarylation of 1‐Alkenyl Carbonyls with Cyano(hetero)aromatics

Comprehensive Summary The alkene hydroarylation reaction is among the most powerful and atom‐economical methodologies in modern organic chemistry to straightforwardly construct the C(sp 2 )−C(sp 3 ) bonds and the C(sp 3 )−H bonds for the selective incorporation of aryl groups into the two olefinic carbon sites leading to valuable complex aryl‐based alkane molecules, which have been proven to be instrumental in the synthesis of many natural products, pharmaceuticals and organic functional materials. Herein, we describe a synergetic photoredox and CO 2 •− catalysis for a regioselective hydroarylation of 1‐alkenyl carbonyls with cyano(hetero)aromatics via radical anion sorting. Using the carbon dioxide radical anion (CO 2 •− ) as a powerful single electron reductant in cooperation with the photoreductive catalysis, this protocol enables the simultaneous formation of dual radical anions through single electron reduction of alkenes and cyano(hetero)aromatics, respectively, followed by radical anion‐radical anion coupling to achieve hydroarylation leading to β ‐(hetero)aryl alkyl carbonyl compounds in a highly regioselective manner. This hydroarylation reaction proceeds under mild conditions, exhibits broad functional‐group compatibility and accommodates a wide range of alkenes and cyano(hetero)aromatics with exquisite regioselectivity.