Diastereoselective synthesis of chroman bearing spirobenzofuranone scaffolds <i>via</i> oxa-Michael/1,6-conjugated addition of <i>para</i>-quinone methides with benzofuranone-type olefins
作者:Hongmei Qin、Qimei Xie、Long He
DOI:10.1039/d2ra03031d
日期:——
A simple and convenient cyclization of ortho-hydroxyphenyl-substituted para-quinone methides with benzofuran-2-one type active olefins via oxa-Michael/1,6-conjugated addition has been developed, which afforded an easy access to enriched functionalized chroman-spirobenzofuran-2-one scaffolds with good to excellent yields (up to 90%) and diastereoselectivities (up to >19 : 1 dr). This reaction provided