Theoretical Studies on Organometallic Chemistry

金属有机配合物的结构和性能研究被公认为是化学中的热点领域。本论文的研究工作围绕着金属有机化学这个主题展开，以手性格氏试剂的生成、金属苯的电子结构、钌基催化剂的催化加氢反应为目标，进行了系统的理论研究，主要结果总结如下： 一、手性的格氏试剂不仅能够作为分子探针用于研究反应机理，更能够作为潜在的手性构筑单元用于不对称合成，但如何直接合成具有手性的格氏试剂目前尚无通用的方法。本文的理论研究表明，在格氏试剂的生成过程中存在两条相互竞争的反应路径：非自由基路径与自由基路径。前者能够得到手性保持的产物，而后者将导致外消旋化产物的生成。进一步的研究揭示，氯代烃比其它卤代烃更有利于生成构型保持的产物；小位阻...Studies on structures and properties of organometallic compounds have been admittedly regarded as a hot field of chemistry. In this thesis, the organometallic chemistry is our subject. The formation of chiral Grignard reagent, the electronic configuration of metallabenzene complexes, and the selective hydrogenation of cinnamaldehyde by ruthenium hydride catalyst have been selected for our theoreti...学位：理学博士院系专业：化学化工学院化学系_物理化学学号：2052008015017

FeO~+(~6Σ~+)催化CO还原N_2O的理论研究

在B3LYP/6-311+G(2d)//B3LYP/6-31G(d)计算水平下,考察了FeO+(6Σ+)分子如何催化CO还原N2O微观机理.计算结果表明,FeO+(6Σ+)是一种有效的催化剂,其可从N2O中夺取一个O原子,然后再传递给CO,完成整个氧转移过程.结果发现,反应中可能生成各种过氧[Fe(O2)+]或双端氧(OFeO+)物种,其中前者比较稳定,后者更活泼

Density Functional Method Studies on Configuration and Electronic Structure of R-ReO_3

在X3LYP/6-311+G(2d,p)的水平下系统地研究了一系列高价有机铼氧化物(R—ReO3.Ln)的几何构型和电子结构.研究结果表明,用X3LYP方法预测的几何结构与实验值符合得很好,键长的误差一般小于0.001 nm,而键角的误差小于1°.同时发现不同配位类型的R基和L配体显著影响铼氧化合物的酸性以及Re—O键能.应用NBO分析和前线轨道理论可以合理地阐明配体调变的实质.We performed a systematic densities functional(X3LYP) study on the configuration and electronic structures of a series of high valence organorhenium oxides(R-ReO35Ln).Our calculations show that X3LYP function can give a good description of rhenium oxide geometries.In most cases,the deviations of bond lengths from the experimental results are less than 0.001 nm,while the errors of bond angels are around 1°.We found that the Lewis acidity and the strength of the Re-O bond could be subtly tuned by various R groups as well as amine ligands such that rhenium oxo can play a versatile role in catalytic oxidation.These results are rationalized in terms of NBO analysis and frontier orbital theory.国家自然科学基金(批准号:20525311,20533030和20503022)资

How To Prepare a Chiral Grignard Reagent: A Theoretical Proposal

It is shown that two competitive pathways (T2 vs T4) exist for Grignard reagent formation. While the nonradical pathway T2 leads to retention of the configuration, the radical pathway T4 gives racemization. Our calculations suggest the way that T2 can be enhanced, which should be of significance to prompt new synthesis approaches for the preparation of chiral Grignard reagents.National Natural Science Foundation of China[91027044, 20923004]; Ministry of Science and Technology[2007CB815206, 2011CB8504

Theoretical Studies on the Reduction of N2O by CO on FeO+ ((6)Sigma(+))

The reduction of N2O by CO was Investigated at the level of B3LYP/6-311 + G (2d)//B3LYP/6-31G(d) using FeO+ as a model catalyst. The calculation results show that FcO(+) is an effective catalyst which can pick up the O atom from N2O and then deliver it to CO to accomplish the overall O-transfer. Two species, Fe(O-2)(+) and OFeO+, were located during the reactions. While Fe (O-2)(+) is found to be more stable than OFeO+; the latter is shown to be more active than the former

Density Functional Method Studies on Configuration and Electronic Structure of R-ReO3

We performed a systematic densities functional (X3LYP) study on the configuration and electronic structures of a series of high valence organohenium oxides (R-ReO3 (.) L-n). Our calculations show that X3LYP function can give a good description of rhenium oxide geometries. In most cases, the deviations of bond lengths from the experimental results are less than 0.001 nm, while the errors of bond angels are around 1 degrees. We found that the Lewis acidity and the strength of the Re-O bond could be subtly tuned by various R groups as well as amine ligands such that rhenium oxo can play a versatile role in catalytic oxidation. These results are rationalized in terms of NBO analysis and frontier orbital theory

Theoretical Studies on Thermochemistry for Conversion of 5-Chloromethylfurfural into Valuable Chemicals

Recently, 5-chloromethylfurfural (CMF) was proposed as a central, intermediate in the conversion of carbohydrate-based material into useful organic commodities. In the present work, we have calculated the thermochemistry using the highly accurate G4 theory and several state-of-art density functional theory (DFT) methods (e.g., x1, M06-2X, B2PLYP-D, and XYG3) for the conversion from CMF to 5-hydroxymethylfurfural (HMF) and levulinic acid (LA) in water, and that to biofuels 5-ethoxymethylfurfural (EMF) and ethyllevulinate (EL) in alcohol. New reaction mechanisms have been proposed, which complement the well-recognized Horvat mechanisms. The assessment of DFT methods suggested that XYG3 be a viable method for biomass related thermochemistry calculations.National Natural Science Foundation of China[91027044, 20973138, 21133004]; Ministry of Science and Technology of China[2007CB815206, 2011CB808505]; Synfuels China Co. Ltd