2-羟基-β-硝基苯乙烯与硫叶立德的[4+1]环加成反应构建二氢苯并呋喃类化合物

Synthesis of 2,3-Dihydrobenzofurans via [4+1]Cycloaddition of 2-( 2-Nitrovinyl) phenol with Sulfur Ylides

在无催化剂的条件下,研究了2-羟基-β-硝基苯乙烯与硫叶立德的[4+1]环加成反应,考察了溶剂和温度对反应收率及非对映选择性的影响,以99%的收率和>20/1的非对映选择性合成了一系列2,3-二氢苯并呋喃类化合物,其结构经1H NMR,13C NMR和HR-MS(ESI-TOF)确证。

The[4+1]cycloaddition of 2-(2-nitrovinyl)phenol with sulfur ylides was explored under the catalyst-free condition.The effects of solvent and temperature on the reaction were investigated,and a series of 2,3-dihydrobenzofurans were obtained in excellent yields(up to 99%)with high diastereoselectivities(up to>20/1).The structures were confirmed by 1 H NMR,13 C NMR and HR-MS(ESI-TOF).