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Chemoselective Cross-Coupling of gem-Borazirconocene Alkanes with Aryl Halides
Chao Yang1,2, Yadong Gao1,2, Songlin Bai2
1School of Chemical Engineering, Nanjing University of Science and Technology, Nanjing, Jiangsu 210094, China.
Abstract:
The direct and chemoselective conversion of the carbon-metal bond of gem-dimetallic reagents enables rapid and sequential formation of multiple carbon-carbon and carbon-heteroatom bonds, thus representing a powerful method for efficiently increasing structural complexity. Herein, we report a visible-light-induced, nickel-catalyzed, chemoselective cross-coupling reaction between gem-borazirconocene alkanes and diverse aryl halides, affording a wide range of alkyl Bpin derivatives in high yields with excellent regioselectivity. This practical method features attractively simple reaction conditions and a broad substrate scope. Additionally, we systematically investigated a Bpin-directed chain walking process underlying the regioselectivity of alkylzirconocenes, thus uncovering the mechanism of the remote functionalization of internal olefins achieved with our method. Finally, DFT calculations indicate that the high regioselectivity of this reaction originates from the directing effect of the Bpin group.
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