Catalysis of nucleophilic substitution reactions in supramolecular systems

The factors determining the catalytic effect of supramolecular systems on the nucleophilic substitution reactions are analyzed. The role of the structural and phase transitions of nanoaggregates in the catalytic mechanism are determined. The substrate specificity is shown for different structures of the supramolecular composition.     

Donor-acceptor properties, catalytic activity, and negative charge exoemission from the alumina surface modified with lithium cations

Donor-acceptor properties of alumina modified with lithium cations were studied by ESR of paramagnetic complexes of adsorbed anthraquinone. The results were compared with the data on negative ion emission (exoemission) accompanying the decomposition of isopropyl alcohol in the adsorption layer. The data on the activity measured by the pulse microcatalytic technique in isopropyl alcohol decomposition are discussed. Small additives of lithium were found to promote catalytic activity of the samples. The role of acid and basic sites in isopropyl alcohol decomposition was discussed. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 616–621, April, 2006.     

Supramolecular systems based on poly(ethyleneimines) and calix[4]resorcinarenes with alkylphosphonate fragments. Aggregation and catalytic activity

Aggregation in poly(ethylenimine)-calix[4]resorcinarene-water-DMF systems was studied by the methods of conductometry and dynamic light scattering. The sizes (radii) of the aggregates formed and the critical micelle concentrations were determined. The catalytic activity for these systems in the hydrolisys of phosphorus acid esters was shown. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 924–931, May, 2007.     

An unusual new reaction of α-olefins with magnesiumn-alkyl derivatives catalyzed by Cp2ZrCl2

The reaction of organomagnesium compounds (OMC) containing alkyl radicals of normal structure with -olefins, resulting in the formation of alkenylorganomagnesium compounds and accompanied by hydride transfer was discovered and systematically investigated. A scheme providing for the formation of zirconacyclopentane complexes was proposed for the mechanism of the reaction.Institute of Organic Chemistry, Ural Branch, Russian Academy of Sciences, 450054 Ufa. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 5, pp. 1187–1196, May, 1992.     

Molecular beams and model catalysis: activity and selectivity of specific reaction centers on supported nanoparticles.

Reaction kinetics on nanometer-scale particles are different from those on extended surfaces of bulk materials. This fact has been utilized for a long time to empirically maximize the performance of heterogeneous catalysts, but the understanding of the underlying effects is poor at the microscopic level. Modern molecular beam-based methods, however, allow us to derive very detailed kinetic information on catalytically active surfaces. In combination with structurally highly controlled model catalysts, microscopic insights into the activity and selectivity of specific reaction centers on catalyst nanoparticles can be obtained. This combined approach is illustrated through simple model reactions.     

甲醇催化分解动力学之研究

甲醇的裂解产物为H_2与CO,故甲醇被视为一种方便、安全的贮氢材料,可作为汽油的代用燃料;其裂解气作为保护气氛可广泛应用于热处理工业。甲醇裂解有两种方法,高温热裂解(约930℃)与低温催化裂解(约300℃)由于低温催化裂解有诸多优点,在工业上的应用正在发展。     

铁(Ⅲ)-柠檬酸盐配合物光解引发橙黄Ⅱ的脱色

介绍了金属卟啉化合物的结构、种类及其应用，综述了金属卟啉化合物对烷烃的仿生催化氧化研究进展。运用金属卟啉仿生催化空气氧化环己烷制备环己酮技术，使得停留在实验室研究水平的金属卟啉仿生催化烷烃空气氧化进入了工业化生产。     

含锆层柱蒙脱石对1,2,4三甲基苯歧化反应的催化作用

用离子共聚法合成了硅锆层柱蒙脱石（ＳｉＺｒＰＩＬＭ）和铁锆层柱蒙脱石（ＦｅＺｒＰＩＬＭ），考察了它们对１，２，４三甲基苯（１，２，４ＴｒＭＢ）歧化反应的催化性能．１，２，４ＴｒＭＢ在催化剂样品上可发生歧化反应和异构化反应，歧化反应选择性达８０％以上．随着催化剂预处理温度的提高，１，２，４ＴｒＭＢ转化率下降，歧化反应选择性和四甲基苯（ＴｅＭＢ）中１，２，４，５ＴｅＭＢ含量则升高．催化剂对１，２，４ＴｒＭＢ歧化反应有择形催化作用，１，２，４，５ＴｅＭＢ和间二甲苯、邻二甲苯为主要产物，并且其含量偏离其热力学平衡组成，ＴｅＭＢ中１，２，４，５ＴｅＭＢ的含量在８５％以上．