Theoretical Studies on Proton Transfer Reactions of 8-Hydroxyquinoline Monomers and Dimers  

作　　者：赵继阳 周子彦 苏忠民 谢玉忠 孙光延 吴学 

机构地区：[1]Department of Chemistry, College of Science, Yanbian University, Yanji, Jilin 133002, China [2]Institute of Functional Material Chemistry, Faculty of Chemistry, Northeast Normal University, Changchun, Jilin 130024, China [3]Key Laboratory of Natural Resources of the Changbai Mountain and Functional Molecules, Ministry of Education, Yanbian University, Yanji, Jilin 133002, China

出　　处：《Chinese Journal of Chemistry》2006年第6期724-730,共7页中国化学（英文版）

基　　金：Project supported by the National Natural Science Foundation of China （No. 20162005） and the Science and Technology Development Program of Jilin Province of China （No. 20020664）.

摘　　要：Density functional theory （DFT） of quantum chemistry method was employed to investigate proton transfer reactions of 8-hydroxyquinoline （8-HQ） monomers and dimers. By studying the potential energy curves of the isomerization, the most possible reaction pathway was found. The total energy of 8-hydroxyquinoline was lower than that of quinolin-8（1H）-one, whereas the order was reversed in dimers. The findings explained the contrary experimental phenomena. The minimum reaction barrier of intramolecular proton transfer was 47.3 kJ/mol while that in dimer was only 25.7 kJ/mol. Hence it is obvious that proton transfer reactions of 8-HQ monomer have a considerable rate but it is easier to proceed for 8-HQ dimer than monomers. It implied that the hydrogen bond played an important role in depressing the activation energy of reaction. The mechanism of the tautomerization was discussed on the basis of theoretical results.Density functional theory （DFT） of quantum chemistry method was employed to investigate proton transfer reactions of 8-hydroxyquinoline （8-HQ） monomers and dimers. By studying the potential energy curves of the isomerization, the most possible reaction pathway was found. The total energy of 8-hydroxyquinoline was lower than that of quinolin-8（1H）-one, whereas the order was reversed in dimers. The findings explained the contrary experimental phenomena. The minimum reaction barrier of intramolecular proton transfer was 47.3 kJ/mol while that in dimer was only 25.7 kJ/mol. Hence it is obvious that proton transfer reactions of 8-HQ monomer have a considerable rate but it is easier to proceed for 8-HQ dimer than monomers. It implied that the hydrogen bond played an important role in depressing the activation energy of reaction. The mechanism of the tautomerization was discussed on the basis of theoretical results.

关 键 词：8-HYDROXYQUINOLINE proton transfer TAUTOMERIZATION density functional theory transition state 

分 类 号：O626.323[理学—有机化学]