Brønsted Acid Catalyzed (3+2)‐Cycloaddition of Thioketones and Indole‐2‐Carbinols Toward Thiazolo[3,4‐a]indoles

Abstract

Abstract Herein, we report a Brønsted acid catalyzed approach to access the yet unknown heterocyclic motif of thiazolo[3,4‐a]indoles in a one‐pot reaction under very mild conditions. A broad range of thiazolo[3,4‐a]indoles was generated from indole‐2‐methanols and thioketones with 45–99% yield and good functional group tolerance. The practicality of the process and the synthetic potential of the products were demonstrated with an upscaling experiment and further transformations. Additional control experiments provided mechanistic insights into this cycloaddition. magnified image