Enantioselective Nitroaldol Reaction of α-Keto Esters Catalyzed by a Copper(II)-Bisoxazolidine Complex
作者:Christian Wolf、Hanhui Xu
DOI:10.1055/s-0030-1259000
日期:2010.11
A wide range of aliphatic and aromatic α-keto esters has been transformed to α-hydroxy-β-nitro esters via the Cu(II)-bisoxazolidine-catalyzed Henry reaction. In the presence of 10 mol% of the chiral catalyst, nitroaldol products were obtained in up to 95% yield and 76% ee.
Enantioselective addition of nitromethane to α-keto esters catalyzed by copper(<scp>ii</scp>)–iminopyridine complexes
作者:Gonzalo Blay、Victor Hernández-Olmos、José R. Pedro
DOI:10.1039/b716446g
日期:——
The coppercomplex of a chiral iminopyridine easily prepared from (R)-(-)-fenchone and picolylamine catalyzes the enantioselective Henry (nitroaldol) reaction between nitromethane and alpha-keto esters. Good yields and modest to good enantioselectivities are obtained for a wide range of alpha-keto esters, bearing aromatic, alkyl or alkenyl groups attached to the ketone carbonyl group.
Enantioselective Nitroaldol Reaction of α-Ketoesters Catalyzed by Cinchona Alkaloids
作者:Hongming Li、Baomin Wang、Li Deng
DOI:10.1021/ja057237l
日期:2006.1.1
The development of highly enantioselective and general catalytic nitroaldol (Henry) reactions with ketones is a challenging yet desirable task in organic synthesis. In this communication, we report an asymmetric nitroaldol reaction with alpha-ketoesters catalyzed by a new C6'-OH cinchonaalkaloid catalyst. This is the first highly efficient organocatalytic asymmetric Henry reaction with ketones. This
Copper-Catalyzed Enantioselective Henry Reactions of α-Keto Esters: An Easy Entry to Optically Active β-Nitro-α-hydroxy Esters and β-Amino-α-hydroxy Esters
作者:Christina Christensen、Karsten Juhl、Rita G. Hazell、Karl Anker Jørgensen
DOI:10.1021/jo025690z
日期:2002.7.1
The catalytic enantioselective Henry reaction of alpha-keto esters with nitromethane has been developed. The reaction conditions have been optimized by the screening of different chiral Lewis acids, solvents, and bases, and it was found that the copper(II)-tert-butyl bisoxazoline complex in combination with triethylamine catalyzed a highly enantioselective reaction giving opticallyactive beta-nitro-alpha-hydroxy