Theoretical Study On The Structures And Synthesis Mechanism Of The Organogermanium Sesquioxide And Sesquisulfur

Much attention has been shown in organic germanium compounds since Japanese chemist first found the Ge-132(carboxyethyl germanium sesquioxide), which appeared to be less toxic. So far organic germanium compounds have become very unprecedented development. Some scholars home and abroad have sought to synthesis and development for new products, but the theoretical studies are scarce. (GeCH2CH2CONH2)2O3 and (GeCH2CH2COCl)2S3 are very important organic germanium compounds. In present work, a systematic and theoretical investigation of the two compounds was carried out, and the results will be valuable for better understanding the reaction mechanism.We studied many important reactions involved in the synthesis processes of (GeCH2CH2CONH2)2O3 and (GeCH2CH2COCl)2S3 basised on density functional methods of quantum chemistry. This thesis is divided two parts: in the first section of theoretical study on the reaction mechanism of acetamidethylgermanium sesquioxide, we have studied the addition reaction of HGeCl3 and CH2CHCN, hydrolyzation reaction of GeCl3CH2CH2CN and H2O; in the second section of theoretical study on the reaction mechanism of chlorideethyl organogermanium sesquisulfur, we have systematicly studied the chlorination reaction of GeCl3CH2CH2COOH and SOCl2, reaction of GeCl3CH2CH2COCl and H2S.The important and meaningful results in this thesis can be summarized as follows:1. In the the addition reaction of HGeCl3 and CH2CHCN, the reactants, transition states, and products have been optimized respectively at the B3LYP/6-311g(d,p) , B3LYP/6-311++g(3df,3pd) and BB1K/6-311g(d,p)level, and more accurate results are get at BB1K/6-311g(d, p) level. Two possible reactant channel are get and energies, vibrational frequencies are calcutated at BB1K/6-311g(d,p)level. Solvent effects are taken into account with PCM model. The rate constants in the wide temperature 200-3500 K for each reaction channel are calculated by canonical variational transition state theory (CVT) with the small-curvature tunneling (SCT) at BB1K/6-311g(d,p) level. The preliminary study shows the dominating reaction pathway.2. In the hydrolyzation reaction of GeCl3CH2CH2CN and H2O, we have thoroughly optimized all the stable structures and transition states by different methods in the same level, and vibrational frequencies are calcutated at BB1K/6-311g(d,p)level. This reaction has two reaction channels, corresponding thermodynamics and solvent effects are taken at the same level, and dominating reaction pathway are get.3. In the chlorination reaction of GeCl3CH2CH2COOH and SOCl2, the reactants, transition states, and products have been optimized respectively. Eight possible reactant channel are get and energies, vibrational frequencies are calcutated, corresponding thermodynamics and solvent effects are taken at the same level.4. In the reaction of GeCl3CH2CH2COCl and H2S, the reactants, transition states and products have been optimized respectively. Six possible reactant channel are get and energies, vibrational frequencies are calcutated, results in this part can be summarized as follows: hydrolysation of Cl proceed more easily than that of CN radical.We make great efforts to get the systemic and accurate results during the study. Actually, many valuable results are obtained. This will guide promise the development of theoretical and practical study on the organic germanium compounds.