Benzo[c]cinnoline derivatives. VII. Reactions of Benzo[c]cinnoline and Chlorobenzo[c]cinnolines with lithium dimethylamide.

Abstract

The reactions of the four isomeric chlorobenzo[c]cinnolines and unsubstituted benzo[c]cinnoline with lithium dimethylamide in dimethylamine lead to the formation of complex product mixtures. Di- methylaminations occur as primary reactions at the 4- and 7-positions of the benzo[c]cinnoline nucleus; these involve displacement of hydrogen even when a chloro substituent is attached to another position in the same ring. Nucleophilic displacement of chloro substituents (in most instances as secondary reactions) appears to involve both direct (AE) substitution and EA cinesubstitution. With the 2-chloro compound 1,3-telesubstitution occurs as a primary reaction.