Rhodium-Catalyzed Carbonylative Synthesis of Aryl Salicylates from Unactivated Phenols

Org Lett. 2020 Aug 7;22(15):6050-6054. doi: 10.1021/acs.orglett.0c02133. Epub 2020 Jul 27.

Abstract

A rhodium-catalyzed carbonylative transformation of unactivated phenols to aryl salicylates is described. This protocol is characterized by utilizing 1,3-rhodium migration as the key step to provide direct access to synthesize o-hydroxyaryl esters. Various desired aryl o-hydroxybenzoates were produced in moderate to excellent yields with bis(dicyclohexylphosphino)ethane (DCPE) as the ligand. Interestingly, diphenyl carbonate was formed as the main product when 1,3-bis(diphenylphosphino)propane (DPPP) was used as the ligand. A plausible reaction mechanism is proposed.