Reducing-Agent-Free Convergent Synthesis of Hydroxyimino-Decorated Tetracyclic Fused Cinnolines via Rh<sup>III</sup>-Catalyzed Annulation Using Nitroolefins
Pidiyara Karishma, Chikkagundagal K. Mahesha, Sanjay K. Mandal, Rajeev Sakhuja
Abstract
A mild Rh-catalyzed method was developed for the synthesis of hydroxyimino functionalized indazolo[1,2-a]cinnolines and phthalazino[2,3-a]cinnolines by reductive [4 + 2] annulation between 1-arylindazolones and 2-aryl-2,3-dihydrophthalazine-1,4-diones with varied nitroolefins. The targeted oxime decorated tetracyclic fused cinnolines were synthesized via sequential C–H activation/olefin insertion/reduction under reducing-agent-free conditions.
Topics & Concepts
AnnulationOximeChemistryOlefin fiberCatalysisArylCombinatorial chemistryStereochemistryMedicinal chemistryOrganic chemistryAlkylCatalytic C–H Functionalization MethodsCatalytic Cross-Coupling ReactionsCyclopropane Reaction Mechanisms