Facile Synthesis of the Fused 6-6-5 Ring System Containing Chroman Ring from 2-(1-Hydroxy-5-alkenyl)phenol Derivatives via Intramolecular Inverse-Electron-Demand Diels–Alder Reaction
A simple and facile synthesis of the fused 6-6-5 ring system, i.e., 1,2,3,3a,4,9b-hexahydrocyclopenta[c][1]benzopyrans, was achieved through the intramolecular [4+2] cycloaddition of o-quinonemethides generated from 2-(1-hydroxy-5-alkenyl)phenol derivatives under acidic conditions. In general, cis-fused tricyclic compounds of 6-6-5 ring system were obtained as the major products. Reactivity and selectivity
Ag-Catalyzed Selective C–C Bond Activation of Cyclopropenones to Access α-Alkylidene Lactones
作者:Shu-Lin Zhang、Zhao-Bing Wu、Chun-Xin Zhao、Yu-Xin Bai、Wei Sun、Meng Sun
DOI:10.1021/acs.orglett.4c01853
日期:2024.7.26
opening of unsymmetric cyclopropenones for the stereoselective synthesis of a diverse range of α-alkylidene lactones has been developed. In this protocol, two different C–C(O) bonds were distinguished, demonstrating selectiveC–Cbond activation. This reaction features a wide substrate scope, good functional group compatibility, and high atom economy, providing a versatile and general approach to the