A Family of Thiazolium Salt Derived N-Heterocyclic Carbenes (NHCs) for Organocatalysis: Synthesis, Investigation and Application in Cross-Benzoin Condensation
作者:Isabel Piel、Marius D. Pawelczyk、Keiichi Hirano、Roland Fröhlich、Frank Glorius
DOI:10.1002/ejoc.201100870
日期:2011.10
A family of thiazolium salt derived N-heterocycliccarbenes (NHCs) bearing sterically demanding aryl substituents on the nitrogen and with varying backbone substitution patterns have been synthesized. Investigation of the catalytic activity of these NHCs in a number of benzoin-type coupling reactions revealed markedly different levels of reactivity and selectivity. To elucidate the underlying factors