Enzymatic Kinetic Resolution and Racemization of 2-(Tetramethylpiperidine-1-oxyl)ethanols
作者:Agnes Prechter、Markus R. Heinrich
DOI:10.1002/ejoc.201300661
日期:2013.9
The Candida antarctica lipase B catalyzed transesterification of 2-(tetramethylpiperidine-1-oxyl)ethanols provides acetates in useful yields with good to high enantiomeric excess values. By taking advantage of the persistent radical effect, the remaining alcohols can be cleanly racemized under mild conditions in the presence of TEMPO [2,2,6,6-tetramethylpiperidin-1-yl)oxidanyl].
南极念珠菌脂肪酶 B 催化的 2-(四甲基哌啶-1-氧基) 乙醇的酯交换以有用的产率提供具有良好至高对映体过量值的乙酸盐。通过利用持久的自由基效应,剩余的醇可以在温和条件下在 TEMPO [2,2,6,6-四甲基哌啶-1-基)氧烷基]的存在下完全外消旋。
One-pot sequential alcohol oxidation and asymmetric α-oxyamination in aqueous media using recyclable resin-supported peptide catalyst
An efficient tandem reaction system was developed, in which primary alcohols were used for the oxidation to the corresponding aldehydes followed by an asymmetric alpha-oxyamination with a resin-supportedpeptidecatalyst.
Asymmetric α-oxyamination of aldehydes by synergistic catalysis of imidazolethiones and metal salts
作者:Xianrui Liang、Na Li、Xinlei Chen、Weike Su
DOI:10.1039/c4ra08556f
日期:——
Novel and efficient imidazolethione catalysts combined with metal salts were successfully introduced to the asymmetric α-oxyamination of aldehydes. The desired products with high yields and good to excellent enantioselectivities were obtained via a one-pot oxidation–oxyamination reaction system.