Carbon Tetrachloride-Mediated Cyclization of (2-Alkynyl)arylaldimines for the Synthesis of Polychlorinated Nitrogen Heterocycles.

An unprecedented use of carbon tetrachloride to mediate the 6-endo-dig cyclization of (2-alkynyl)arylaldimines, generated in situ from (2-alkynyl)arylaldehydes and primary amines, has been developed via formal insertion of C═N and C≡C bonds into a C-Cl bond under catalyst-free conditions, providing convenient access to a range of structurally diverse polychlorinated 1,2-dihydroisoquinolines and heteroarene-fused nitrogen heterocycles.