A Radical Cascade Enabling Collective Syntheses of Natural Products

Summary Natural products have long been important inspirations for the development of chemical methodologies, theories, and technologies, and ultimately, discoveries of new drugs and materials. Chemical syntheses have traditionally yielded individual or small groups of natural products; however, methodology development allowing the synthesis of a large collection of natural products remains scarce. Here, we report an efficient photocatalytic radical cascade method that enables access to libraries of chiral and multiple-ring-fused tetrahydrocarbolinones. The radical cascade can controllably introduce complexity and functionality into products with excellent chemo-, regio-, and diastereoselectivity. The power of this distinct method has been demonstrated by the efficient syntheses of 33 monoterpenoid indole alkaloids belonging to four families.