Synthesis of pyrazolo[1,5-<i>c</i>]quinazoline derivatives through the copper-catalyzed domino reaction of <i>o</i>-alkenyl aromatic isocyanides with diazo compounds
Lu Liu, Lei Li, Shukuan Mao, Xin Wang, Mingdong Zhou, Yu‐Long Zhao, He Wang
Abstract
A novel copper-catalyzed domino reaction between o-alkenyl aromatic isocyanides and diazo compounds has been developed under mild reaction conditions. Various o-alkenyl aromatic isocyanides were prepared from readily available reactants. The reaction provides a general and efficient method for the synthesis of pyrazolo[1,5-c]quinazolines by the formation of two rings and three new bonds in a single step from readily available acyclic starting materials. A mechanism involving a tandem (3+2) cyclization/elimination/intramolecular aza-addition sequence was proposed.
Topics & Concepts
DiazoChemistryDominoCascade reactionIntramolecular forceCatalysisTandemCombinatorial chemistryCopperReaction conditionsReaction mechanismQuinazolineMedicinal chemistryOrganic chemistryMaterials scienceComposite materialQuinazolinone synthesis and applicationsCatalytic C–H Functionalization MethodsN-Heterocyclic Carbenes in Organic and Inorganic Chemistry