The tautomers of quinazolinonide‐substituted imidazolium betaines are N‐heterocyclic carbenes which form cyclic boron adducts as well as thiones and selenones. The anionic substituent allowed for the examination of electronic effects on the carbene carbon atom, among others, by ⁷⁷Se NMR measurements.

中文翻译：

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喹唑啉-4-一咪唑甜美甜菜碱的甜菜碱-N-杂环碳素相互转化。硫，硒和硼烷加合物的形成

喹唑啉酮取代的咪唑鎓甜菜碱的互变异构体是N-杂环卡宾，它们形成环状硼加合物以及硫酮和硒酮。阴离子取代基允许通过⁷⁷ Se NMR测量来检查对卡宾碳原子的电子效应。