Novel Photoinitiated Synthesis, Characterization, Thermal Kinetics, and Mechanism of Complex of Potassium Hexacyanoferrate with Imidazole  

作　　者：MAJID Kowsar AHMAD Siraj MALIK Mukhtar Ahmad 

机构地区：[1]Department of Chemistry, National Institute of Technology

出　　处：《Chemical Research in Chinese Universities》2009年第2期138-142,共5页高等学校化学研究（英文版）

摘　　要：Photoinitiated substitution complex of [Fe（CN）6]^4- with imidazole has been synthesized and characterized. On the basis of elemental analysis, the empirical molecular formula of the complex is K4[Fe（CN）5（C3H4N2）]·4H2O. The substitution of aquo ligand produced as a result of photoexcitation by imidazole has been confirmed by various spectroscopic thechniques like UV-Vis, FTIR, NMR, and SEM techniques. The characteristic FTIR and NMR absorption peaks for different entities present support the assigned formula. The presence of cyanide and imidazole ligands is shown by FTIR absorption peaks at 2046 cm^-1 due to v（C≡N） and at 1447 and 1619 cm^-1 due to v（C=N） and v（C=C） stretching vibration of the aromatic ring of imidazole, hence, confirming the assigned formula and photoinitiated substitution process. ^1HNMR also shows the peaks for aromatic hydrogen confirming again the presence of imidazole in the complex, further supporting the successful photoinitiated process. The water outside the coordination sphere has been confirmed from FTIR peaks and thermal analysis. Thermal kinetics and mechanistic studies have also been carried out by TG and DSC, Thermodynamics parameters such as activation energy（Ea）, preexponential factor（A）, and entropy of activation（Aft） have been calculated for each step via different methods like Doyle＇s, Coats, and Redfern and Arrehenius.Photoinitiated substitution complex of [Fe（CN）6]^4- with imidazole has been synthesized and characterized. On the basis of elemental analysis, the empirical molecular formula of the complex is K4[Fe（CN）5（C3H4N2）]·4H2O. The substitution of aquo ligand produced as a result of photoexcitation by imidazole has been confirmed by various spectroscopic thechniques like UV-Vis, FTIR, NMR, and SEM techniques. The characteristic FTIR and NMR absorption peaks for different entities present support the assigned formula. The presence of cyanide and imidazole ligands is shown by FTIR absorption peaks at 2046 cm^-1 due to v（C≡N） and at 1447 and 1619 cm^-1 due to v（C=N） and v（C=C） stretching vibration of the aromatic ring of imidazole, hence, confirming the assigned formula and photoinitiated substitution process. ^1HNMR also shows the peaks for aromatic hydrogen confirming again the presence of imidazole in the complex, further supporting the successful photoinitiated process. The water outside the coordination sphere has been confirmed from FTIR peaks and thermal analysis. Thermal kinetics and mechanistic studies have also been carried out by TG and DSC, Thermodynamics parameters such as activation energy（Ea）, preexponential factor（A）, and entropy of activation（Aft） have been calculated for each step via different methods like Doyle＇s, Coats, and Redfern and Arrehenius.

关 键 词：PHOTOCHEMISTRY Potassium he.xacyanoferrate IMIDAZOLE Photosubstitution FTIR 

分 类 号：O626.23[理学—有机化学]