<i>anti</i>-Selective Catalytic Asymmetric Nitroaldol Reaction of α-Keto Esters: Intriguing Solvent Effect, Flow Reaction, and Synthesis of Active Pharmaceutical Ingredients
nitroalkanes and α-ketoesters in an anti-selective manner to afford synthetically versatile, densely functionalized, and optically active α-nitro tertiary alcohols. A chiral diamide ligand captured two distinct metal cations, giving rise to a catalytically competent solid-phase heterobimetallic catalyst by simple mixing via self-assembly. The advantage of the solid-phase asymmetric catalyst was realized
A series of N,N′-dialkylated derivatives of (1R,2R)-cyclohexane-1,2-diamine were synthesized, and a new approach to the one-pot preparation of this type of amine was demonstrated. The prepared diamines were used as organocatalysts for the two-stepsynthesis of α-hydroxy γ-keto esters from arenes, chlorooxoacetates, and ketones; they were also used as chiral ligands for Meervein–Ponndorf–Verley reductions
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.
The Construction of Quaternary Stereocenters by the Henry Reaction: Circumventing the Usual Reactivity of Substituted Glyoxals
作者:Gonzalo Blay、Víctor Hernández‐Olmos、José R. Pedro
DOI:10.1002/chem.201002888
日期:2011.3.21
enantioselective Henry reaction between alkyl‐ and arylglyoxal hydrates and nitromethane catalyzed by CuII–iminopyridine complexes takes place regioselectively on the ketone carbonyl group to give chiral tertiary nitroaldols with high functional group density and enantiomeric excesses of up to 96 %. Both aromatic and aliphatic glyoxals are suitable substrates for this reaction.
Cu II-亚氨基吡啶络合物催化的烷基和芳基乙二醛水合物与硝基甲烷之间的对映选择性亨利反应在酮羰基上区域选择性地发生,从而得到具有高官能团密度和高达96%的对映体过量的手性叔硝基醛醇。芳族和脂族乙二醛都是适合该反应的底物。