Metal‐Free Formation of Xanthenes and Xanthones from 2‐aryloxybenzaldehydes via Intramolecular Cyclization

Abstract We herein report a metal‐free strategy for the selective synthesis of xanthenes and xanthones from 2‐aryloxybenzaldehydes. By employing a phosphorous acid/iodine system, we achieved the efficient preparation of diverse xanthenes via intramolecular reductive cyclization. In contrast, a series of xanthones were selective constructed from the same substrates through TBAI‐catalyzed intramolecular direct cyclization. This methodology offers notable advantages, including straightforward workup, absence of metal involvement, and low‐cost. A plausible reaction mechanism was also proposed.