mind, we report a catalytic Friedel‒Crafts alkylation method catalyzed by a charged thiourea incorporating a cationic cyclopropenium moiety. Mechanistic studies, including density functional theory computational calculations, variable time normalization analysis, and 1H NMR binding studies, collectively reveal this charged-enhanced reactivity proceeds by a dual hydrogen bond-mediated LUMO-lowering
Enantioselective Friedel-Crafts Alkylation of<i>N</i>-Methylindoles with Nitroalkenes Catalyzed by Chiral Bifunctional Abietic-Acid-Derived Thiourea-Zn<sup>II</sup>Complexes
作者:Wei-gen Huang、Heng-shan Wang、Guo-bao Huang、Yong-ming Wu、Ying-ming Pan
DOI:10.1002/ejoc.201200584
日期:2012.10
The catalytic asymmetric Friedel–Craftsalkylation of N-methylindoles with nitroalkenes catalyzed by bifunctional abietic-acid-derived thiourea-ZnII complexes was investigated. Various types of the nitroalkylated indoles were synthesized under mild conditions and obtained with excellent yields (up to 99 %) and good enantioselectivities (up to 86 % ee). These chiral thiourea catalysts are easily available