Tin Tetrachloride-Catalyzed Regiospecific Allylic Substitution of Quinone Monoketals: An Easy Entry to Benzofurans and Coumestans
作者:Yingjie Liu、Jingxin Liu、Mang Wang、Jun Liu、Qun Liu
DOI:10.1002/adsc.201200344
日期:2012.10.8
A highly regioselective allylic substitution of quinone monoketals with α-oxoketene dithioacetals is achieved under the catalysis of only tin tetrachloride (1 mol%). The advantages of the reaction, including its simplicity, rapidity, low catalyst loading of inexpensive tin tetrachloride, mild conditions and; in particular, the regiospecificity, is proposed to be due to a pseudo-intramolecular process
在仅四氯化锡(1摩尔%)的催化下,α-氧杂环丁烯二硫缩醛可对区域性单酮缩酮进行高度区域选择性的烯丙基取代。该反应的优点包括其简单,快速,廉价的廉价四氯化锡催化剂负载量,温和的条件,以及;特别地,区域特异性被认为是由于拟分子内过程引起的。这种新的合成方法为苯并呋喃提供了一种简便的[3 + 2]环加成路线,并通过合成香豆素而得到了强调。