ligands were designed and synthesized. The rhodium complexes with the ligands were applied to the asymmetric transfer hydrogenation of broad range of long-chained aliphatic ketoesters in neatwater. Quantitative conversion and excellent enantioselectivity (up to 99% ee) was observed for α-, β-, γ-, δ- and ε-ketoesters as well as for α- and β-acyloxyketone using chiral surfactant-type catalyst 2. The CH/π
Synthesis and absolute stereochemistry of hagen's-gland lactones in some parasitic wasps (Hymenoptera:Braconidae)
作者:Gregory C. Paddon-Jones、Christopher J. Moore、Douglas J. Brecknell、Wilfried A. König、William Kitching
DOI:10.1016/s0040-4039(97)00661-8
日期:1997.5
Efficient syntheses and enantioselective gas chromatography have confirmed the structures and established the absolute stereochemistry of some novel bicyclic lactones (tetrahydrofurofuranones) in species of parasitic wasps (Hymenoptera:Braconidae). The co-occurring γ-lactones, octan-4-olide and dodecan-4-olide, have the (R)-configuration.
Ligand effects in aluminium-catalyzed asymmetric Baeyer–Villiger reactions
作者:Jean-Cédric Frison、Chiara Palazzi、Carsten Bolm
DOI:10.1016/j.tet.2005.12.080
日期:2006.7
AsymmetricBaeyer–Villigeroxidations of racemic and prochiral cyclobutanones can be performed with chiral aluminium-based Lewis acids resulting in products with good enantioselectivities in high yields. By employing substituted BINOL derivatives as ligands, remarkable catalyst efficiencies have been achieved and γ-butyrolactones with up to 84% ee were obtained. The relation between the electronic
Asymmetric synthesis via axially dissymmetric molecules. 7. Synthetic applications of the enantioselective reduction by binaphthol-modified lithium aluminum hydride reagents
作者:R. Noyori、I. Tomino、M. Yamada、M. Nishizawa
DOI:10.1021/ja00334a042
日期:1984.10
La reaction est applicable a une variete decomposescarbonyles insatures de structures diverses tels que, cetones aromatiques, cetones acetyleniques, cetones ethyleniques et aldehydes. L'utilite est illustree parla synthese fortement stereocontrolee d'intermediaires de prostaglandines, de quelques pheromones d'insectes, d'alcools terpeniques primaires chiraux, de phenyloxiranne optiquement actif
La 反应 est 适用一个 une variete de composes carbonyles insatures destructures different tels que, cetones aromatiques, cetones acetyleniques, cetones ethyleniques et aldehydes。L'utilite est illustree par la synthese fortement Stereocontrolee d'intermediaires de prostaglandines, de quelques pheromones d'insectes, d'alcools terpeniques primaires chiraux, de phenyloxiranne optiquement actif...
Syntheses of rac- and optically active 2-alkyl-γ-butyrolactones and 2 -alkyl-cyclobutanones
作者:Alain Krief、Alain Ronvaux、Arounarith Tuch
DOI:10.1016/s0040-4020(98)00371-8
日期:1998.6
good yield from alkylidene cyclopropanes, as racemates or as an enantiomerically enriched mixture of stereoisomers (e.e.>60%) depending upon the method used. Opticallyactive cyclobutanones which are intermediate in the process have been in some cases isolated. We show the limitations of a competitive method previously described and point out its weak step.