Synthesis of Substituted Imidazolidines: Base-Stable Precursors of 4,5-Dihydro-1<i>H</i>-imidazol-3-ium Salts and<i>N</i>-Heterocyclic Carbenes
作者:Meike Egert、Sebastian Walther、Herbert Plenio
DOI:10.1002/ejoc.201402364
日期:2014.7
1-(4-bromo-2,6-diisopropylphenyl)-3-(2,6-diisopropylphenyl)imidazolidine and 1,3-bis(4-bromo-2,6-diisopropylphenyl)imidazolidine were synthesized and the 4-Br substituents converted into various functional groups through Br/Li exchange or Pd-catalyzed cross-coupling reactions (Suzuki, Sonogashira, and vinylation). The substituted imidazolidines were oxidized, by using chloranil or N-bromosuccinimide,
目前的工作建立了一种新的合成路线,可产生取代的唑鎓盐。合成了碱稳定的 1-(4-溴-2,6-二异丙基苯基)-3-(2,6-二异丙基苯基)咪唑烷和 1,3-双(4-溴-2,6-二异丙基苯基)咪唑烷,4 -Br 取代基通过 Br/Li 交换或 Pd 催化的交叉偶联反应(Suzuki、Sonogashira 和乙烯基化)转化为各种官能团。通过使用氯苯醌或 N-溴代琥珀酰亚胺氧化取代的咪唑烷,以提供相应的唑鎓盐,它们是 N-杂环卡宾的方便前体。