Synthesis of Dibenzofurans via Palladium-Catalyzed Phenol-Directed C-H Activation/C-0 Cyclization

摘要

A practical, Pd(0)/Pd(II)-catalyzed reaction was developed for phenol-directed C—H activation/C—O cyclization using air as an oxidant. The turnover-limiting step of the process was found to be C—O reductive elimination instead of C—H activation. This reaction can tolerate a variety of functional groups and is complementary to the previous methods for the synthesis of substituted dibenzofurans.