One-Step Synthesis of the Benzocyclo[penta- to octa-]isoindole Core

摘要

Owing to the prevalence of heterocyclic compounds in medicinal chemistry and natural products, the development of new transition-metal-catalyzed reactions for the formation of fused heterocycles continues to be an active area of research. The construction of such ring systems by means of C-H activation and Heck coupling is a complementary approach to remarkably powerful domino reactions. Recently, Yu and co-workers reported a promising C-H activation route for the preparation of indolines and tetrahy-droisoquinolines. Fujii and co-workers developed a palladium-catalyzed C(sp~3)-H activation for the direct preparation of indoline derivatives. In a particularly straightforward approach, Chang and co-workers reported the synthesis of condensed pyrroloindoles through the intramolecular func-tionalization of a pyrrole C-H bond. These syntheses exhibit good selectivity and high atom economy, and are carried out under mild reaction conditions at low catalyst loadings.