Lewis base catalysed halofunctionalisation reactions of alkenes are well established and allow access to, among others, various oxygen containing heterocycles. By exploiting the known conversion of N-heterocyclic carbenes into the corresponding thioureas it has been possible to prepare and study a range of chiral and non-chiral Lewis base catalysts for such reactions. Although all thiourea catalysts were found to mediate bromocycloetherification and bromolactonisation reactions, they could not be achieved with enantioselectivity.

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硫脲催化的溴环醚化和溴内酯化的研究

路易斯碱催化的烯烃的卤代官能化反应是公认的，并且除其他外，还可以使用各种含氧杂环。通过利用已知的N-杂环卡宾转化成相应的硫脲的方法，可以制备和研究一系列用于这种反应的手性和非手性路易斯碱催化剂。尽管发现所有的硫脲催化剂都可介导溴环醚化和溴内酯化反应，但对映选择性不能实现。