Selective Synthesis of Isochromene Fused Indenone or Indane Fused Indanone Derivatives Featuring with Solvent-Dependent Intra- or Intermolecular O–H Bond Carbene Insertion

. To our knowledge, such a solvent-dependent selective O-H bond carbene insertion leading to the formation of distinct polycyclic compounds from the same starting materials has not been reported previously. In general, the protocols developed herein feature high efficiency, good atom/step-economy, broad substrate scope and ready scalability. Moreover, the products could be readily transformed into other valuable products.