Synthesis of π-Extended Imidazoles by 1,3-Dipolar Cycloaddition of Polycyclic Aromatic Azomethine Ylides with Nitriles
Qiang‐Qiang Li, Kotaro Ochiai, C. Lee, Shingo Ito
Abstract
Here we report the 1,3-dipolar cycloaddition of polycyclic aromatic azomethine ylides with nitriles to produce highly fused imidazole derivatives, that is, tribenzo[b,g,ij]imidazo[2,1,5-de]quinolizine. The advantages of this transformation are the broad substrate scope and the good functional group compatibility. The subsequent palladium-catalyzed intramolecular cyclization provides an efficient approach to further π-extended imidazoles, that is, 14b1,15-diazadibenzo[fg,ij]cyclopenta[rst]pentaphene.
Topics & Concepts
ChemistryIntramolecular forceCycloadditionImidazoleAzomethine ylidePalladium1,3-Dipolar cycloadditionNitrileCombinatorial chemistryCatalysisStereochemistryOrganic chemistryCatalytic C–H Functionalization MethodsCyclopropane Reaction MechanismsSynthesis and Characterization of Pyrroles