Synthesis of Polysubstituted 3-Chalcogenated Indoles through Copper(I) Iodide-Catalyzed Three-Component Domino Reactions

Abstract

Polysubstituted 3-chalcogenated indoles were synthesized by a three-component, one-pot, domino reaction of a N-(2-bromophenyl)trifluoroacetamide, a 1-alkyne, a disulfides or diselenides, CuI, and proline in DMF. In this process, tandem Sonogashira coupling, N-cyclization, and sulfenyl/selenyl electrophilic substitution occurred sequentially and smoothly to form the anticipated products in good to excellent yields (20 examples; 65–96%). Notably, no palladium catalyst was used in this catalytic system, supporting its cost effectiveness and potential industrial application.