Diversity-oriented synthesis of benzofuro[3,2-<i>b</i>]pyridine derivatives from aurone-derived α,β-unsaturated imines and activated terminal alkynes
Bin Cheng, Hui Li, Xuecheng Zhu, Xinping Zhang, Yixuan He, Haiyan Sun, Taimin Wang, Hongbin Zhai
Abstract
An efficient annulation reaction of aurone-derived α,β-unsaturated imines and activated terminal alkynes mediated by triethylamine is described, which enables the facile synthesis of 1,4-dihydrobenzofuro[3,2-b]pyridines in high yields. When the nucleophile of triethylamine was replaced with triphenylphosphine, another class of 1,4-dihydrobenzofuro[3,2-b]pyridines tethered with an additional acrylate motif were obtained instead. These two types of 1,4-dihydrobenzofuro[3,2-b]pyridines could be aromatized in the presence of DBU to afford benzofuro[3,2-b]pyridines, which could also be accessed via a one-pot procedure.
Topics & Concepts
Terminal (telecommunication)ChemistryCatalysisPyridineMedicinal chemistryStereochemistryOrganic chemistryComputer scienceTelecommunicationsCatalytic C–H Functionalization MethodsSynthesis of Organic CompoundsSynthesis and Reactivity of Heterocycles