Synthesis of Chromenopyrroles (Azacoumestans) from Functionalized Enones and Alkyl Isocyanoacetates
Bubul Das, Anjali Dahiya, Nikita Chakraborty, Bhisma K. Patel
Abstract
Elegant synthetic strategies for chromenopyrroles (azacoumestans) have been devised via cycloaddition of 2-hydroxychalcone/cyclic enones and alkyl isocyanoacetate, followed by lactonization. Herein, ethyl isocyanoacetate acts as a C–NH–C–C═O synthon contrary to its hitherto applications as a C–NH–C synthon. Subsequently, pentacyclic-fused pyrroles were also constructed from the o -iodo benzoyl chromenopyrroles using the Pd(II) catalyst.
Topics & Concepts
SynthonChemistryCycloadditionAlkylCatalysisEnoneStereochemistryOrganic chemistrySynthesis and Characterization of PyrrolesCatalytic C–H Functionalization MethodsOxidative Organic Chemistry Reactions