Counterion effects in iminium-activated electrophilic aromatic substitutions of pyrroles

被引：21

作者：

Lakhdar, Sami ^{[1
]}

Mayr, Herbert ^{[1
]}

机构：

[1] Univ Munich, Dept Chem, D-81377 Munich, Germany

来源：

CHEMICAL COMMUNICATIONS | 2011年 / 47卷 / 06期

关键词：

STEREOSELECTIVE ALPHA-ALKYLATION; ASYMMETRIC ORGANOCATALYSIS; ORGANIC CATALYSIS; X-RAY; ALDEHYDES; IMIDAZOLIDINONES; NUCLEOPHILICITY; REACTIVITIES; STRATEGIES; ADDITIONS;

D O I：

10.1039/c0cc04295a

中图分类号：

O6 [化学];

学科分类号：

0703 ;

摘要：

Electrophilic substitution of pyrroles by alpha,beta-unsaturated iminium ions is slow in acetonitrile when only weakly basic counterions are present. When the reactions are carried out in the presence of KCF3CO2, fast deprotonation of the intermediate sigma-adducts occurs, and the rate constant for the rate-determining CC bond-forming step can be predicted from the electrophilicity parameter E of the iminium ion and the N and s parameters of the pyrroles.

引用

收藏

页码：1866 / 1868

页数：3

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