Divergent Conversion of Double Isocyanides with Alkenyl Bromide to Polysubstituted Pyrroles and 4-Imino-4,5-dihydropyrrolo[3,4-<i>b</i>]pyrrol-6(1<i>H</i>)-one Derivatives by Pd-Catalyzed Tandem Cyclization Reactions
Zhi‐Lin Ren, Ji‐Ying Qiu, Ling-Ling Yuan, Yue-Fei Yuan, Shuang Cai, Jun Li, Chi Kong, Ping He, Long Wang
Abstract
Herein a novel and concise approach to pyrrole skeletons via Pd-catalyzed tandem cyclization reactions is investigated. The substrates for the transformation could be readily prepared by phosphoric acid-catalyzed Ugi reactions with available starting materials. In this strategy, two isocyanides participate in sequential isocyanide insertion reactions, and the chemoselectivity of the products is regulated by the steric hindrance of the isocyanide. A plausible mechanism for the formation of the corresponding adducts is proposed.
Topics & Concepts
ChemistryIsocyanideSteric effectsChemoselectivityCombinatorial chemistryAdductPyrroleTandemBromideStereochemistryCatalysisMedicinal chemistryOrganic chemistryMaterials scienceComposite materialSynthesis and Characterization of PyrrolesCatalytic C–H Functionalization MethodsMulticomponent Synthesis of Heterocycles