A Route to Annulated Indoles via a Palladium-Catalyzed Tandem Aikyiation/Direct Arylation Reaction

摘要

Traditionally,catalytic methods for biaryl formation involve transition metal-catalyzed coupling between an organometallic component with an aryl halide or pseudohalide.More recently,considerable attention has been given to the direct arylation of heteroarenes,achieved via cross-coupling of heteroaromatic sp~2 C-H bonds and aryl halides.A direct arylation approach allows for carbon-carbon bond formation without the need for prior functionalization of the heteroarene via metalation.One important application of direct arylation is the functionalization of indoles since many biologically active natural products as well as phar-maceutically important compounds contain this privileged motif.