HPLC enantioseparation of various racemates using novel pillared homochiral MOF–silica composite as chiral stationaryphase has been successfully demonstrated.
Bovine serum albumin–cobalt(<scp>ii</scp>) Schiff base complex hybrid: an efficient artificial metalloenzyme for enantioselective sulfoxidation using hydrogen peroxide
An artificial metalloenzyme (BSA–CoL) based on the incorporation of a cobalt(II) Schiffbase complex CoL, H2L = 2,2′-[(1,2-ethanediyl)bis(nitrilopropylidyne)]bisphenol} with bovine serum albumin (BSA) has been synthesized and characterized. Attention is focused on the catalytic activity of this artificial metalloenzyme for enantioselective oxidation of a variety of sulfides with H2O2. The influences
人工金属酶(BSA–CoL),其基于钴(II)Schiff碱络合物CoL,H 2 L = 2,2'-[((1,2-乙二基)双(亚硝酰丙二炔)]双酚}与牛的结合血清白蛋白(BSA)已被合成和表征。注意力集中在这种人工金属酶对H 2 O 2对多种硫化物的对映选择性氧化的催化活性上。。研究了pH,温度,催化剂和氧化剂浓度等参数对硫代苯甲醚的影响。在最佳条件下,BSA–CoL作为杂化生物催化剂可有效地对一系列硫化物进行对映选择性氧化,产生相应的亚砜,具有优异的转化率(最高100%),化学选择性(最高100%)和良好的对映体纯度(最高在某些情况下为87%ee)。
Efficient Asymmetric Oxidation of Sulfides and Kinetic Resolution of Sulfoxides Catalyzed by a Vanadium−Salan System
作者:Jiangtao Sun、Chengjian Zhu、Zhenya Dai、Minghua Yang、Yi Pan、Hongwen Hu
DOI:10.1021/jo040221d
日期:2004.11.1
The asymmetricoxidation of sulfides to chiral sulfoxides with hydrogen peroxide in good yield and high enantioselectivity has been catalyzed very effectively by chiral vanadium−salan [N,N‘-alkyl bis(salicylamine)] complex. The salan ligand shows results superior in terms of reactivity and enantioselectivity to those of salen [N,N‘-alkylene bis(salicylideneimine)] analogue, and provides the sulfoxide
frontier in the development of chiral stationary phases for chromatographic enantioseparation involves homochiral metal–organic frameworks (MOFs). Using enantiopure (R)-2,2′-dihydroxy-1,1′-binaphthalene-6,6′-dicarboxylic acid as a starting material, we prepared three homochiral MOFs that were further used as chiral stationary phases for high-performanceliquidchromatography to separate the enantiomers
Chiral Ionic Liquids as Stationary Phases in Gas Chromatography
作者:Jie Ding、Thomas Welton、Daniel W. Armstrong
DOI:10.1021/ac049144c
日期:2004.11.1
Recently, it has been found that room-temperature ionic liquids can be used as stable, unusual selectivity stationary phases. They show “dual nature” properties, in that they separate nonpolar compounds as if they are nonpolar stationary phases and separate polar compounds as if they are polar stationary phases. Extending ionic liquids to the realm of chiral separations can be done in two ways: (1) a chiral selector can be dissolved in an achiral ionic liquid, or (2) the ionic liquid itself can be chiral. There is a single precedent for the first approach, but nothing has been reported for the second approach. In this work, we present the first enantiomeric separations using chiral ionic liquid stationary phases in gas chromatography. Compounds that have been separated using these ionic liquid chiral selectors include alcohols, diols, sulfoxides, epoxides, and acetylated amines. Because of the synthetic nature of these chiral selectors, the configuration of the stereogenic center can be controlled and altered for mechanistic studies and reversing enantiomeric retention.