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Development of Epoxidation of Alkenes with Molecular Oxygen Catalyzed by Metal-substituted Polyoxometalates

金属取代多金属氧酸盐催化分子氧环氧化烯烃的研究进展

基本信息

批准号：
14350423
负责人：
MIZUNO Noritaka
金额：
$ 10.94万
依托单位：
The University of Tokyo
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
2002
资助国家：
日本
起止时间：
2002 至 2003
项目状态：
已结题

项目摘要

(1) Lacunary POM as an efficient epoxidation catalyst with hydrogen peroxide.The lacunary Keggin-type silicodecatungstate has been used as a catalyst precursor for epoxidation of olefins with H_2O_2 at 305 K. The catalytic epoxidation proceeded with【greater than or equal】 99% selectivity to epoxide, 【greater than or equal】99% efficiency of H_2O_2 utilization, high stereospecificity, and the easy recovery of the catalyst.(2) Bis (μ-oxo) bridged di-Iron site on the lacunary POM as an efficient epoxidation catalyst with molecular oxygen.Bis (オ-oxo) bridged di-iron site on the lacunary POM has been used as catalysts for the oxygenation of alkenes in homogeneous reaction media using molecular oxygen as an oxygen donor. It is remarkable that selectivity to cyclooctene oxide and turnover number reached up to 98% and 10000, respectively, for the oxygenation of cyclooctene. Not only cyclooctene but also cyclododecene, 1-octene, 2-octene, 2-heptene and 2-hexene were catalytically oxygenated with high turnover numbers and high selectivity to the corresponding epoxides.(3) Microstructured POMs as a shape-selective catalyst.Keggin-type polyoxometalate, SiW_<12>O_<40>^<4->, and Cr(III) trinuclear cation, Cr_3O(OOOCH)_6(H_2O)_3^+, assembled in the presence of K^+ to create a channeled complex K_3[Cr_3O(OOCH)_6(H_2O)_3]SiW_<12>O_<40>・16H_2O with an opening of 0.5 x 0.8 nm. The complex reversibly absorbs water and polar organic molecules smaller than C2. The guest inclusion was highly selective and even a difference of one methylene group in the organic guest molecule was discriminated. Polar organic molecules with longer methylene chain and non-polar molecules were completely excluded. The distinctive guest inclusion was successfully applied to the oxidation of methanol from a mixture of alcohols.

(1)间位聚甲醛作为高效的过氧化氢环氧化催化剂。本文以keggin型十钨酸硅为催化剂前驱体，在305k下用H_2O_2催化烯烃环氧化反应。催化环氧化反应对环氧化物的选择性大于等于99%，H_2O_2利用率大于等于99%，立体专一性高，催化剂易于回收。(2)双（μ-氧）在多孔POM上桥接双铁位点，作为一种高效的分子氧环氧化催化剂。在均相反应介质中，以分子氧为供氧源，将双氧（-氧）桥接双铁位用作烯烃的氧合催化剂。值得注意的是，环烯的氧化选择性和周转率分别高达98%和10000。除环烯外，环十二烯、1-辛烯、2-辛烯、2-庚烯和2-己烯均以高转化率和高选择性催化氧化生成相应的环氧化合物。(3)微结构聚甲醛作为形状选择催化剂。keggin型多金属氧酸盐SiW_<12>O_<40>^<4->，和Cr（III）三核阳离子Cr_3O(OOOCH)_6(H_2O)_3^+，在K^+存在下组装形成通道络合物K_3[Cr_3O(OOCH)_6(H_2O)_3]SiW_<12>O_<40>·16H_2O，其开孔为0.5 x 0.8 nm。该络合物可逆地吸收水和小于C2的极性有机分子。客体包合物具有很高的选择性，甚至有机客体分子中一个亚甲基的差异也能被区分出来。完全排除了亚甲基链较长的极性有机分子和非极性分子。独特的来宾包合物已成功地应用于甲醇的氧化从一种混合物的醇。