Tetrabutylammonium Chloride-Triggered 6-endo Cyclization of o-Alkynylisocyanobenzenes: An Efficient Synthesis of 2-Chloro-3-Substituted Quinolines.

A highly efficient one-pot synthesis of 2-chloro-3-substituted quinolines has been developed by tetrabutylammonium chloride-triggered 6-endo cyclization of o-alkynylisocyanobenzenes, which are generated in situ by dehydration of the corresponding N-(2-ethynylphenyl)formamides.