Facile Synthesis of Gem-Difluoroalkene-Based Bis(silanes) via Copper-Catalyzed Disilylative Defluorination of 1-Chloro-1-trifluoromethylalkenes.

Development of efficient methods to access multifunctional gem-difluoroalkenes is of great importance for medicinal and materials chemistry. While monofunctionalized derivatives of such molecules are well-established, scaffolds bearing two transformable handles remain scarce, particularly those featuring silicon groups. Herein, we report a copper-catalyzed disilylative defluorination of readily available 1-chloro-1-trifluoromethylalkenes. This reaction employs commercial organosilylboranes to directly furnish gem-difluoroalkene-based bis(silanes) with broad substrate scope, excellent functional-group tolerance, under mild conditions. The protocol establishes the first general access to this valuable class of compounds, installing two silicon groups─often with distinct steric and electronic profiles─in a single operation. This method demonstrates scalability and versatility, as evidenced by gram-scale synthesis and diverse downstream derivatizations of the products. An asymmetric variant has also been developed, delivering enantioenriched bis(silanes) with high efficiency and selectivity. This work fills a critical gap in fluorinated building block synthesis and provides a robust platform for accessing complex, silicon-bearing fluoroorganic architectures.