A new and highly efficient water-soluble copper complex for the oxidation of secondary 1-heteroaryl alcohols by tert-butyl hydroperoxide

The water-soluble copper complex generated in situ from CuCl₂ and 2,2′-biquinoline-4,4′-dicarboxylic acid dipotassium salt (BQC), has been revealed as a highly efficient and selective catalyst for the oxidation of secondary 1-heteroaryl alcohols to the corresponding heteroaromatic ketones with aqueous tert-butyl hydroperoxide, under mild conditions. The catalytic system is compatible with different heterocycles such as pyridines, pyrroles, indoles, thiophens, furans, thiazoles, and imidazoles.     

Syntheses of antimony(v) derivatives from trimethyl and triphenylantimony(III), dihydric phenols,andtert-butyl hydroperoxide

Trimethyl and triphenylantimonyo-phenylene dioxides were obtained by the reaction of trimethyl- and triphenylantimony with pyrocatechol in the presence oftert-butyl hydroperoxide in 68 and 81 % yields, respectively. 7,7,7,15,15,15-Hexamethyl-(and phenyl)-6,8,14,16-tetraoxa-7, 15-distibatricyclo[11.3.1.1^9,13]octadeca-1,3,5,9,11,13-hexaenes were synthesized analogously by the reaction with resorcinol (in 79 and 93 % yields, respectively). The use of hydroquinone resulted in polymeric trimethyl- and triphenylantimony hydroquinolates.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 748–751, April, 1995.This work was carried out with financial support from the Russian Foundation for Basic Research (Project No 94-03-08846).     

三氟甲基叔丁基氮氧自由基的超精细偶合常数与溶剂极性参数的相关性研究

用EPR方法测定了三氟甲基叔丁基氮氧自由基在16种溶剂中的顺磁参数α_N和α_F^β值.并对α_N值与溶剂的极性参数E_T、z进行了线性相关分析,讨论了这类低位阻含氟自旋探针对研究溶剂化和探针本身结构的作用.     

Selective oxidation of sulfides to sulfoxides using a silica immobilised vanadyl alkyl phosphonate catalyst

A range of sulfides can be selectively oxidised to the corresponding sulfoxides in good yields using catalytic quantities of immobilised vanadyl, cobalt or nickel alkyl phosphonates and the reoxidant sodium bromate or vanadyl alkyl phosphonate with tert-butyl hydroperoxide or aqueous hydrogen peroxide as oxidants.     

水辅助下的OH自由基与CH_3OOH气相反应机理的理论研究

利用量子化学计算方法对单个水分子不存在与存在的情况下OH自由基与CH3OOH的气相氢抽取反应进行了理论研究.在BHand HLYP/6-311++G(2df,2pd)理论水平下优化了所有驻点的几何构型,在此基础上利用CCSD(T)/cc-p VTZ方法对所有驻点的单点能重新进行了计算.计算结果表明,OH自由基与CH3OOH反应的主要通道是OH自由基抽取CH3OOH中的-OH基团上的H原子.在单个水分子存在的情况下,反应的主要通道没有改变,但是水化过渡态的能量显著地降低,显然单个水分子对OH+CH3OOH反应具有催化效应.     

Clean and Efficient Benzylic C-H Oxidation Using a Microflow System

An efficient procedure using microreactors for the oxidation of benzylic compounds is described. This new method is facile, economical, and environmentally friendly. By using microreactors, this oxidation can be accomplished with good yields within 10 s at room temperature.      

Features of α-phenylisopropyl hydroperoxide decomposition catalyzed by cetyltrimethylammonium bromide

The features of cumene oxidation, α-phenylisopropyl hydroperoxide (ROOH) decomposition, and free radical formation in the presence of cetyltrimethylammonium bromide (CTAB) were studied by the kinetic methods and TLC product analysis. It was found that CTAB catalyzes ROOH decomposition to free radicals. The efficiency of an initiating system CTAB—ROOH is by a factor of 2.5 higher than that of a combination CTAB with α-phenylethyl hydroperoxide. In addition, CTAB catalyzes the reactions of ROOH with α-tocopherol and 2,2′-bis[2-(p-dimethylaminophenyl)indane-1,3-dione]. The kinetic characteristics of these reactions were determined. __________ Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1802–1807, August, 2005.     

Radical low-temperature oxidation of dibenzyl sulfide with the triphenylbismuth—tert-butyl hydroperoxide system

The reaction of Ph₃Bi with Bu^tOOH in a mole ratio of 1: 3 in hydrocarbon solvents affords the η²-peroxo complex of triphenylbismuth Ph₃Bi(η²O₂) which oxidizes the C-H bonds of the methylene group of dibenzyl sulfide. The reaction proceeds via the radical mechanism with the formation of intermediate unstable sulfur-containing hydroperoxide. Its decomposition is accompanied by the C-S bond cleavage, resulting in benzaldehyde. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1183–1185, June, 2008.