Microwave-Assisted One-Pot Synthesis of Dibenzo[b,d]oxepines via Domino C-C Coupling and Cyclo-condensation Pathway

Abstract

Microwave-assisted [Pd]-catalyzed domino one-pot approach to dibenzo[b,d]oxepines starting from 2-bromo-/2-iodo-aryl ethers and 2-formylphenylboronic acids/pinacol boronic acid esters have been developed. The overall methodology is comprehended through tandem intermolecular arylation of 2-bromo-/iodo-aryl ethers and subsequent intramolecular cyclo-condensation to accomplish fused cyclic ethers. The present strategy enables quick access to various substituted dibenzo[b,d]oxepine products in good to high yields and with adequate functional group tolerance. In addition, late-stage functionalization has been conducted.