Nickel-Catalyzed\nSynthesis of Silaindanes via Sequential\nC–H Activating 1,5-Nickel Migration and C–Si Activating\n1,4-Nickel Migration

Catalytic reactions involving 1,<i>n</i>-metal\nmigration\nprovide a powerful approach for the synthesis of complex molecular\nskeletons from simple precursors through the activation of unreactive\nbonds. In this work, a nickel-catalyzed synthesis of 3,3-disubstituted\n1-silaindanes, silicon analogues of valuable indanes, was developed\nby the reaction involving 1,5-nickel migration via C–H bond\nactivation and 1,4-nickel migration via C–Si bond activation.\nIt was found that 1,5-nickel migration not only enabled the C–H\nbond activation at a remote position but also controlled the regioselectivity\nof subsequent alkene insertion. The detailed reaction mechanism was\ninvestigated by conducting deuterium labeling experiments and DFT\ncalculations. The results obtained here demonstrate the high potential\nof catalytic reactions involving nickel migrations via C–H\nand C–Si bond activations for the synthesis of useful cyclic\norganosilicon compounds.