Catalytic Enantioselective Oxidation of Bulky Alkyl Aryl Thioethers with H2O2 over Titanium-Salan Catalysts
作者:Konstantin P. Bryliakov、Evgenii P. Talsi
DOI:10.1002/ejoc.201100557
日期:2011.8
procedure for the oxidation of bulky (preferably aryl benzyl substituted) thioethers with hydrogen peroxide in good to high yields and enantioselectivities (up to 98.5 % ee) is reported. The high optical yields are achieved in a tandem stereoconvergent enantioselective oxidation and kinetic resolution process. A reasonable balance between the sulfoxide yield and enantioselectivity could be found by varying
The Stereoselective Oxidation of
<i>para</i>
‐Substituted Benzenes by a Cytochrome P450 Biocatalyst
作者:Rebecca R. Chao、Ian C.‐K. Lau、Tom Coleman、Luke R. Churchman、Stella A. Child、Joel H. Z. Lee、John B. Bruning、James J. De Voss、Stephen G. Bell
DOI:10.1002/chem.202102757
日期:2021.10.21
The efficient and sustainable hydroxylation, epoxidation and sulfoxidation of a wide range of benzene derivatives using an engineered variant of a bacterial cytochromeP450 enzyme is reported. These reactions were catalyzed with high activity, regioselectivity and total turnover number (up to 20,000) and in certain instances these reactions were achieved with high enanatioselectivity (up to 98 % ee
报道了使用细菌细胞色素 P450 酶的工程变体对各种苯衍生物进行有效和可持续的羟基化、环氧化和磺化氧化。这些反应以高活性、区域选择性和总转换数(高达 20,000)催化,在某些情况下,这些反应以高对映选择性(高达 98% ee .)实现。
Efficient HPLC enantiomer separation using a pillared homochiral metal–organic framework as a novel chiral stationary phase
HPLC enantioseparation of various racemates using novel pillared homochiral MOF–silica composite as chiral stationaryphase has been successfully demonstrated.
Incorporation of azobenzene into the linker of bimetallic chiral salen TiIV catalysts allowed the photoswitchable arrangement of the two Ti(salen) units through cis/transphotoisomerization of azobenzene. The differently arranged Ti(salen) units changed their cooperative function to reflect the positional relationships, as a result, their efficiency as cooperative catalysts in asymmetric sulfoxidation
Investigations on the Iron-Catalyzed Asymmetric Sulfide Oxidation
作者:Julien Legros、Carsten Bolm
DOI:10.1002/chem.200400857
日期:2005.2.4
The development of an enantioselective sulfideoxidation involving a chiral iron catalyst and aqueous hydrogen peroxide as oxidant is described. In the presence of a simple carboxylic acid, or a carboxylate salt, the reaction affords sulfoxides with remarkable enantioselectivities (up to 96 % ee) in moderate to good yields. The influence of the structure of the additive on the reaction outcome is reported