A click chemistry approach based on the reaction between alkynylflavins and mono(6-azido-6-deoxy)-β-cyclodextrin has proven to be a useful tool for the synthesis of flavin-cyclodextrin conjugates studied as monooxygenase mimics in enantioselective sulfoxidations.
oxidation of prochiral sulfides to sulfoxides by hydrogen peroxide in aqueous solutions. The alloxazinium unit was appended to the primary face of α- and β-cyclodextrins via a linker with variable length. A series of sulfides was used as substrates: n-alkyl methyl sulfides (n-alkyl = hexyl, octyl, decyl, dodecyl), cyclohexyl methyl sulfide, tert-butylmethyl sulfide, benzylmethyl sulfide and thioanisol. α-Cyclodextrin
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)。
HPLC enantioseparation on a homochiral MOF–silica composite as a novel chiral stationary phase
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
Fe(salan)-Catalyzed Asymmetric Oxidation of Sulfides with Hydrogen Peroxide in Water
作者:Hiromichi Egami、Tsutomu Katsuki
DOI:10.1021/ja071916+
日期:2007.7.1
A new chiral Fe(salan) complex was synthesized, and it was found to serve as an efficient catalyst for asymmetric oxidation of sulfides using hydrogenperoxide in water without surfactant. Not only alkyl aryl sulfides but also various methyl alkyl sulfides were oxidized to the corresponding sulfoxides with high enantioselectivities up to 96% ee. It should be noted that the turnover number of complex