Nucleophilic versus Electrophilic Activation of Hydrogen Peroxide over Zr-Based Metal–Organic Frameworks
作者:Olga V. Zalomaeva、Vasiliy Yu. Evtushok、Irina D. Ivanchikova、Tatyana S. Glazneva、Yuriy A. Chesalov、Kirill P. Larionov、Igor Y. Skobelev、Oxana A. Kholdeeva
DOI:10.1021/acs.inorgchem.0c01084
日期:2020.8.3
acetonitrile solvent. Kinetic modeling on methyl phenyl sulfoxide oxidation coupled with adsorption studies supports a mechanism that involves the interaction of H2O2 with Zr sites with the formation of a nucleophilic oxidizing species and release of water followed by oxygen atom transfer from the nucleophilic oxidant to sulfoxide that competes with water for Zr sites. The nucleophilic peroxo species coexists
基于Zr的金属有机框架(Zr-MOF)UiO-66和UiO-67在非质子溶剂中催化硫醚氧化,对相应的砜具有前所未有的高选择性(在大约50%的硫化物转化率下,只有1当量的H,96-99%)2 O 2)。已使用测试底物,动力学,吸附,同位素(18 O)标记和光谱学工具研究了反应机理。下列事实指出了过氧物种的优良亲核特征:(1)噻吩5-氧化物的氧化过程中亲核参数X Nu = 0.92,加入酸后其亲核参数X Nu = 0.92。(2)砜与亚砜之比为24的甲基苯亚砜与p竞争氧化-溴-甲基苯基硫醚;(3)相对于甲基苯基亚砜,甲基苯基硫醚氧化的初始速率明显降低(k S / k SO = 0.05);(4)Hammett图的正斜率ρ= + 0.42,用于对位取代的芳基甲基亚砜的竞争性氧化。H 2 O 2在Zr-MOF上的亲核活化还通过其催化α,β-不饱和酮中缺电子的C═C键的环氧化以及乙腈溶剂的氧化来证明
Polyoxomolybdate-Calix[4]arene Hybrid: A Catalyst for Sulfoxidation Reactions with Hydrogen Peroxide
polyoxomolybdate–calix[4]arene hybrid 1 has been synthesized and applied as a heterogeneous catalyst in the sulfoxidation of thioethers to sulfoxides and to sulfones under strictly stoichiometric amounts of 30% H2O2 in CH3CN as the solvent. This study represents the first promising example of successful employment of calixarenes–polyoxometalate (POM) hybrid materials in the area of catalytic oxidations.
合成了一种容易获得的聚氧钼酸盐-杯[4]芳烃杂化物1,并作为非均相催化剂在严格化学计量的CH 3 CN中以30%H 2 O 2为溶剂将硫醚硫氧化为亚砜和砜。这项研究代表了在催化氧化领域成功使用杯芳烃-多金属氧酸盐(POM)杂化材料的第一个有希望的例子。
Ti(Phen)(OC<sub>2</sub>H<sub>5</sub>)<sub>2</sub>Cl<sub>2</sub>: a highly efficient pre-catalyst for selective oxidation of organic sulfides to sulfoxides by hydrogen peroxide
作者:Rong-Hui Wu、Jing Wu、Ming-Xin Yu、Long-Guan Zhu
DOI:10.1039/c7ra06883b
日期:——
[Ti(Phen)(OC2H5)2Cl2] (Phen = 1,10-phenanthroline) is reported as a homogeneous pre-catalyst for the selectiveoxidation of organic sulfides to sulfoxides with a stoichiometric amount of 30% aq. H2O2 in CH3OH at room temperature. This catalytic system showed high yield (95–100%) and good selectivity (92–100%) during the catalytic reaction in a short period of time.
据报道,一种新开发并具有结构特征的钛配合物[Ti(Phen)(OC 2 H 5)2 Cl 2 ](Phen = 1,10-菲咯啉)是一种均相的预催化剂,可以将有机硫化物选择性氧化为亚砜。化学计量比为30%的水溶液。室温下在CH 3 OH中的H 2 O 2。该催化体系在短时间内的催化反应过程中显示出高收率(95–100%)和良好的选择性(92–100%)。
Tetradentate platinum and palladium complex emitters containing phenyl-pyrazole and its analogues
申请人:ARIZONA BOARD OF REGENTS ON BEHALF OF ARIZONA STATE UNIVERSITY
公开号:US10020455B2
公开(公告)日:2018-07-10
A phosphorescent emitter or delayed fluorescent and phosphorescent emitters represented by Formula 1 or Formula II, where M is platinum or palladium.