Divalent Ytterbium Complex-Catalyzed Homo- and Cross-Coupling of Primary Arylsilanes

作者：Xiaojuan Liu, Li Xiang, Elisa Louyriac, Laurent Maron, Xuebing Leng, Yaofeng Chen · 发表于：Journal of the American Chemical Society · 年份：2018 · DOI：10.1021/jacs.8b12138 · 被引用次数：66 · 研究领域：Organoboron and organosilicon chemistry、Catalytic Cross-Coupling Reactions、Synthesis and characterization of novel inorganic/organometallic compounds

Redistribution of primary silanes through C–Si and Si–H bond cleavage and reformation provides a straightforward synthesis of secondary silanes, but the poor selectivity and low efficiency severely hinders the application of this synthetic protocol. Here, we show that a newly synthesized divalent ytterbium alkyl complex exhibits unprecedentedly high catalytic activity toward the selective redistribution of primary arylsilanes to secondary arylsilanes. More significantly, this complex also effectively catalyzes the cross-coupling between electron-withdrawing substituted primary arylsilanes and electron-donating substituted primary arylsilanes to secondary arylsilanes containing two different aryls. DFT calculation indicates that the reaction always involve the exothermic formation of a hypervalent silicon upon facile addition of PhSiH 3 to the Yb–E (E = C, H) bond. This hypervalent compound can easily either generate directly the Yb–Ph complex, or indirectly through the formation of Yb–H, that is the key complex for the formation of Ph 2 SiH 2 .