Visible-Light-Induced Nickel-Catalyzed Cross-Coupling with Alkylzirconocenes from Unactivated Alkenes

Transition-metal-catalyzed cross-coupling reactions between naturally abundant sp(3)-hybridized carbon centers facilitate access to diverse molecules with complex three-dimensional structures. Organometallic compounds are among one of the most powerful reagents that are broadly used in carbon-carbon bond formations. Although sp(2)-hybridized organometallic compounds are widely employed in cross-couplings, sp(3)-hybridized organometallic coupling partners are less developed. Herein, we report visible-light-induced single nickel-catalyzed C(sp(3))-C(sp(3)), C(sp(3))-C(sp(2)), and C(sp(3))-C(sp) cross-coupling reactions using alkylzirconocenes, which are easily generated in situ from terminal or internal unactivated alkenes through hydrozirconation and chain walking. This method is mild and applicable for a large range of substrates including primary, secondary, tertiary alkyl, aryl, alkenyl, alkynyl halides, and a variety of alkenes. Mechanistic studies suggest a novel nickel-catalyzed radical crosscoupling pathway, which represents the first visible-light-induced transformation of alkylzirconocenes.