Room Temperature and Phosphine Free Palladium Catalyzed Direct C-2 Arylation of Indoles

摘要

Direct C-H functionalization has emerged over the past few years as an attractive strategy to enhance molecular complexity. However, in spite of major advances in this field, the important aryl-aryl bond formation is still almost exclusively carried out by traditional cross-coupling reactions, which require a differential prefunctionalization of both aryl coupling partners. Indeed, the few currently available methods for direct C-H arylation suffer from the need for drastic conditions, elevated temperatures (125 to 150℃), and long reaction times (24 to 48 h) which significantly limit their scope and functional group tolerance.