An efficient and redox-neutral Rh­(III)-catalyzed C–H activation/[3 + 2] annulation of N-phenoxy amides with propargylic monofluoroalkynes has been realized to afford 3-alkylidene dihydrobenzofurans with an interesting α-quaternary carbon center. Combined experimental and computational mechanistic studies revealed that a Rh­(III)–Rh­(V)–Rh­(III) catalytic pathway/uncatalyzed intramolecular [H···F] bonding-assisted SN2′-type substitution cascade might be involved in the catalytic cycle, thereby enabling an excellent site-/regioselectivity with broad substrate/functional group compatibility, including the complete retention of the highly strained cyclobutyl structure in the 3-position.

The Rh(III)‐catalysed C−H couplings of 1‐naphthols with gem‐difluoromethylene alkynes have been realized for the direct construction of difluorinated dihydrobenzo[de]chromenes with broad substrate/functional group compatibility and good regio‐/chemoselectivity and in an atom‐economic manner. The unique fluorine effects account for the unconventional reaction path involving intramolecular 1,3‐hydrogen migration process to afford the exo‐methylene fragment.

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