Facile Access to 2-Arylindolines and 2-Arylindoles by Microwave-Assisted Tandem Radical Cyclization

Abstract

A new route providing access to 2-arylindoles has been developed. The synthesis consists of a tin-mediated tandem radical cyclization of appropriate precursors to form 2,3-disubstituted dihydroindoles, which in turn are oxidized to yield the corresponding 2-arylindoles. The reactions proceed smoothly under microwave irradiation, furnishing the desired products in good yields.

Key words

indoles - cyclizations - heterocycles - radical reactions - dehydrogenations - microwave irradiation

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Details on the X-ray crystal structure of 14b can be obtained from the Cambridge Crystallographic Data Centre (CCDC 691332).