Combination of Lithium Chloride and Hexafluoroisopropanol for Friedel-Crafts Reactions
作者:Jieping Zhu、Matthieu Willot、JinChun Chen
DOI:10.1055/s-0028-1087566
日期:2009.3
A combination of weak Lewis acid (LiCl) and weak Bronsted acid (hexafluoroisopropanol, HFIP) promotes efficiently the Friedel-Craftsreaction of electron-rich arom. compds. with Et glyoxylate. [on SciFinder (R)]
observed to give N-substituted aryl glycine derivatives in good to excellent yields (up to 93 %) from (ortho-hydroxymethyl)aryl benzoates. A cascade mechanism was proposed for the generation and in situ conjugateaddition of the ortho-quinone methides. This mechanism is strongly supported by our subsequent findings that tertiary amines could promote the process. Different functional groups on the (