Formation of Indoles, Dihydroisoquinolines, and Dihydroquinolines by Ruthenium-Catalyzed Heterocyclizations

Abstract

Indoles, dihydroisoquinolines, and dihydroquinolines were efficiently prepared by ruthenium-catalyzed heterocyclizations of aromatic­ homo- and bis-homopropargyl amines/amides in the presence of an amine/ammonium base-acid pair. These regioselective 5-endo and 6-endo cyclizations most probably occur by nucleophilic trapping of key ruthenium-vinylidene intermediates.

Key words

heterocyclizations - indoles - isoquinolines - quinolones - ruthenium - vinylidenes

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