Construction of gem-Difluoroenol Esters through Catalytic O-Selective Addition of Difluoroenoxysilanes to Ketenes

The O-site reactivity of difluoroenoxysilanes is disclosed for the first time, which enabled the direct construction of versatile gem-difluoroalkenes through an unprecedented highly efficient addition reaction with ketenes. A series of valuable gem-difluoroenol esters were achieved in good to excellent yields. The synthetic versatility of this protocol is further demonstrated by the gram-scale synthesis and good functional group tolerance.

Automated summary

The O-site reactivity of difluoroenoxysilanes has been reported for the first time, allowing for the direct construction of versatile gem-difluoroalkenes through an highly efficient addition reaction with ketenes. A series of valuable gem-difluoroenol esters were synthesized in good to excellent yields, showcasing the synthetic versatility of this method through gram-scale synthesis and good functional group tolerance.