Expedient syntheses of the N-heterocyclic carbene precursor imidazolium salts IPr•HCl, IMes•HCl and IXy•HCl

被引：177

作者：

Hintermann, Lukas ^{[1
]}

机构：

[1] Rhein Westfal TH Aachen, Inst Organ Chem, D-52074 Aachen, Germany

来源：

BEILSTEIN JOURNAL OF ORGANIC CHEMISTRY | 2007年 / 3卷

关键词：

D O I：

10.1186/1860-5397-3-22

中图分类号：

O62 [有机化学];

学科分类号：

070303 ; 081704 ;

摘要：

The 1,3-diaryl-imidazolium chlorides IPr center dot HCl (aryl = 2,6-diisopropylphenyl), IMes center dot HCl (aryl = 2,4,6-trimethylphenyl) and IXy center dot HCl (aryl = 2,6-dimethylphenyl), precursors to widely used N-heterocyclic carbene (NHC) ligands and catalysts, were prepared in high yields (81%, 69% and 89%, respectively) by the reaction of 1,4-diaryl-1, 4-diazabutadienes, paraformaldehyde and chlorotrimethylsilane in dilute ethyl acetate solution. A reaction mechanism involving a 1,5-dipolar electrocyclization is proposed.

引用

页数：5

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