Multicomponent Coupling Cyclization Access to Cinnolines via in Situ Generated Diazene with Arynes, and α-Bromo Ketones.

A transition-metal-free multicomponent coupling cyclization reaction was explored involving arynes, tosylhydrazine, and α-bromo ketones. The reaction proceeds via a formal [2 + 2 + 2] cycloaddition, giving access to cinnoline derivatives in moderate yields under mild conditions. Three chemical bonds were formed-two C-N bonds and one C-C bond-in a single step.