Enhancement of the Efficiency of the Low Temperature Method for Kinetic Resolution of Primary Alcohols by Optimizing the Organic Bridges in Porous Ceramic-Immobilized Lipase
作者:Takashi Sakai、Kyoko Hayashi、Fumika Yano、Mie Takami、Megumi Ino、Toshinobu Korenaga、Tadashi Ema
DOI:10.1246/bcsj.76.1441
日期:2003.7
For the enhancement of enantioselectivity and acceleration of the reaction rate in the lipase-catalyzed resolution of primary alcohols, the use of a very low reaction temperature (−30 °C) and an immobilized lipase on organic bridges-coated porous ceramic support was found to be highly effective. Furthermore, the structure of the organic bridges greatly influenced the temperature effect between ln E and 1/T as well as the reaction rate. Among the organic bridges examined in the resolution of (±)-2-hydroxymethyl-1,4-benzodioxane, the 6-(2-methylpropanoyloxy)hexylsilanetrioxyl bridge was the best choice for both the E value and the reaction rate at −30 °C.
Synthesis of epoxy (meth)acrylic esters by selective epoxidation of unsaturated (meth)acrylic esters using the system H2O2 - Na2WO4 under phase transfer catalysis
作者:Y. Fort、A. Olszewski-Ortar、P. Caubere
DOI:10.1016/s0040-4020(01)90120-6
日期:1992.1
Selective epoxidation of unsaturated (meth)acrylic esters by various classical epoxidizing agents was investigated. It is shown that high selectivity and good yields are obtained by using the system H2O2 (20%) - Na2WO4 under phase transfer catalysis. Under these conditions, the rigorous control of the temperature and of the initial pH allows to prevent polymerization during these selective epoxidations
研究了各种经典的环氧化剂对不饱和(甲基)丙烯酸酯的选择性环氧化。结果表明,在相转移催化下,通过使用H 2 O 2(20%)-Na 2 WO 4体系可以得到高选择性和高收率。在这些条件下,严格控制温度和初始pH值可防止在这些选择性环氧化过程中发生聚合。结果表明,环氧化的选择性取决于两个双键亲核性的差异。
Preparation of Organosilicon Compound Having (Meth)acryloyloxy Group
申请人:Shin-Etsu Chemical Co., Ltd.
公开号:US20210139515A1
公开(公告)日:2021-05-13
A (meth)acryloyloxy-containing organosilicon compound (3) is prepared by simultaneously feeding a hydrohalosilane compound (1) and a (meth)acrylate compound (2) in the presence of a polymerization inhibitor to a reaction system, and effecting hydrosilylation reaction in the presence of a platinum catalyst. The content of (meth)acrylate compound (2) is 0-100 mol % based on the content of organosilicon compound (3) in the reaction system. R is a C
1
-C
10
monovalent hydrocarbon group, X is halogen, n is 1, 2 or 3, R
2
is H or methyl, and R
3
is a C
1
-C
18
alkylene group.