(3+2) Annulationof Donor–Acceptor Cyclopropaneswith Difluoroenoxysilanes: Syntheses of <i>gem</i>-Difluorocyclopentenesvia α,α-Difluoroketone Scaffolds

Herein, we present an acid- and base-mediated approach for ring opening of donor–acceptor cyclopropanes (DACs) followed by (3+2) annulation, yielding biologically relevant <i>gem</i>-difluorinated cyclopentenes via α,α-difluoroketone scaffolds. Fluorinated rings are essential building blocks in drug discovery and materials research. This methodology has a broad substrate scope, is scalable, and provides a practical synthetic route to obtain value-added fluorinated compounds.