Synthesis of 3-Substituted 1-Thioacyl- and 1-Thiocarbamoylindoles from α-Substituted 2-Isocyanato-β-methoxystyrenes

Abstract

3-Aryl-1-thioacylindoles were prepared by treating α-aryl-2-isothiocyanato-β-methoxystyrenes with organolithiums or Grignard reagents, followed by hydriodic acid catalyzed cyclization of the resulting adducts. A one-pot synthesis of 1-thiocarbamoylindoles was achieved by hydriodic acid mediated cyclization of the corresponding thiourea intermediates, prepared from α-substituted 2-isothiocyanato-β-methoxystyrenes and secondary amines.

Key words

heterocycles - indoles - cyclizations - isothiocyanates - organometallic reagents

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