Divergent Access to 1-Naphthols and Isocoumarins via Rh(III)-Catalyzed C-H Activation Assisted by Phosphonium Ylide.

Rh-catalyzed C-H activation of phenacyl phosphoniums in coupling with α-diazocarbonyl compounds has been realized with the assistance of a mutifunctional phosphonium ylidic directing group, providing expedient accesses to 1-naphthols and isocoumarins. Switchable synthesis of 1-naphthols and isocoumarins was realized by substrate control, where these transformations were enabled by initial C-H activation and subsequent intramolecular Wittig reaction or nucleophilic C-O formation.