Z-iodovinylfurans and 2-acyl furans promoted by NIS via controllable cyclization of ynenones is reported. The reaction proceeded by sequential 5-exo-dig electrophilic cyclization to intermediate 2-(iodomethylene)-2H-furanium cation D, providing a range of synthetically valuable and useful trisubstituted furan derivatives 2 and 3 in moderate to excellent yields. This approach is metal-free, mild, and atom-economic,
据报道,NIS通过可控制的
炔诺酮环化而合成了Z-
碘乙烯基呋喃和2-酰基
呋喃。反应通过顺序地5-exo-dig亲电环化进行,以生成中间体2-(
碘亚甲基)-2H-
呋喃阳离子D,以中等到极好的收率提供了一系列具有合成价值的有用的三取代
呋喃衍
生物2和3。该方法无
金属,温和且经济实惠,具有良好的选择性和高的立体选择性。