Polystyrene-supported cu(II)-R-Box as recyclable catalyst in asymmetric Friedel–Crafts reaction
作者:V. G. Desyatkin、M. V. Anokhin、V. O. Rodionov、I. P. Beletskaya
DOI:10.1134/s1070428016120010
日期:2016.12
complex of copper(II) trifluoromethanesulfonate with chiral isopropyl bis(oxazoline) ligand (i-Pr-Box) was immobilized on accessible and inexpensive Merrifield resin according to a “click” procedure. The resulting catalyst showed high efficiency and recyclability in the asymmetricFriedel–Craftsalkylation of indole and its derivatives. The catalyst can be recycled five times without appreciable loss in
Enantioselective Friedel–Crafts alkylation of indoles with β,γ-unsaturated α-ketoesters catalyzed by new squaramide-linked bisoxazoline–Zn(OTf)2 complexes
作者:Sheng-Jian Jia、Da-Ming Du
DOI:10.1016/j.tetasy.2014.05.011
日期:2014.7
Enantioselective Friedel-Crafts alkylation reactions of indoles with beta,gamma-unsaturated alpha-ketoesters catalyzed by novel chiral C-2-symmetric squaramide-linked bisoxazoline-Zn(OTf)(2) complexes were investigated. The corresponding indole ketoesters were obtained in good to excellent yields (up to 98%) and with high enantioselectivities (up to 94% ee). This is the first report on the use of chiral squaramide-linked bisoxazoline SQBOX in a catalytic enanitioselective Friedel-Crafts alkylation reaction. (C) 2014 Elsevier Ltd. All rights reserved.