Stereoselective β–F Elimination Enabled Redox-Neutral [4 + 1] Annulation via Rh(III)-Catalyzed C–H Activation: Access to Z‑Monofluoroalkenyl Dihydrobenzo[d]isoxazole Framework

An efficient and practical Rh­(III)-catalyzed redox-neutral [4 + 1] annulation of N-phenoxy amides with α,α-difluoromethylene alkynes has been realized to give direct access to the Z-configured monofluoroalkenyl dihydrobenzo­[d]­isoxazole framework with broad substrate compatibility and good functional group tolerance, which was further enhanced by the late-stage C–H modification of complex bioactive compounds. Subsequent density functional theory calculations revealed that the stereoselective β–F elimination involving an allene species played a decisive role in determining the reaction outcome and such Z-selectivity.