Azo compounds as key intermediates in the synthesis of cinnolines. Recent advances
Xabier Jiménez-Aberásturi1, Xabier Del Corte1, Jesús M de Los Santos1
1Department of Organic Chemistry I, Faculty of Pharmacy and Lascaray Research Center, University of the Basque Country (UPV/EHU), Paseo de la Universidad 7, 01006 Vitoria-Gasteiz, Spain. jesus.delossantos@ehu.eus.
Abstract:
Over the past decades, azo compounds have emerged as versatile and efficient building blocks for the construction of cinnoline frameworks due to their ready availability, structural diversity, and unique reactivity profiles. This review provides a comprehensive overview of recent advances in the use of azo compounds for cinnoline synthesis, highlighting transition-metal-catalyzed C-H activation modern strategies, cycloaddition reactions and classical methods (von-Richter, Widman-Stoermer or Borsche-Herbert).
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