One-Pot Synthesis of Xanthones and Thioxanthones by the Tandem Coupling−Cyclization of Arynes and Salicylates

[reaction: see text] The reaction of silylaryl triflates, CsF, and salicylates affords a general and efficient way to prepare biologically interesting xanthones and thioxanthones. This chemistry presumably proceeds by a tandem intermolecular nucleophilic coupling and subsequent intramolecular electrophilic cyclization.