Synthetic utility of 4′-nitrobenzenesulfenanilide in the functionalization of carbon-carbon double and triple bonds : Its use in the bromosulfenylation of alkenes and alkynes
作者:Luisa Benati、Pier Carlo Montevecchi、Piero Spagnolo
DOI:10.1016/s0040-4020(01)82386-3
日期:1993.6
formation of diphenyl disulfide essentially ascribable to preferred decomposition of the highly unstable benzenesulfenyl bromide intermediate. The present additions of benzenesulfenyl bromide to alkenes and alkynes are believed to involve the initial intermediacy of thiiranium- and thiirenium-like ions, respectively, by analogy with related AdE reactions of sulfenyl chlorides.
4'-硝基苯亚磺酰苯胺(NBSA)与氢溴酸的反应,适当地在室温下在环己烯,-hex-3-ene,hex-1-ene和3,3-二甲基丁-1-烯的存在下进行定量分离相应的2-溴烷基苯硫醚通过亲电加成初始形成的苯硫基溴化物到烯烃双键上,获得-立体特异性和抗马尔科夫尼科夫区域特异性。在单-和双-取代的烷基-和苯基-乙炔的存在下,类似的反应通常以良好的产率提供(E)-2-溴乙烯基苯基硫化物,其随着所用炔的亲核力的降低而降低。但是,在母体乙炔的存在下,几乎没有形成相应的硫化物加合物,而是几乎排他地形成了二硫化二苯,这基本上是由于高度不稳定的苯硫基溴化物中间体的优选分解所致。据信目前向烯烃和炔烃中添加苯硫基溴化物分别涉及th离子和th离子的初始中间体,磺酰氯的E反应。