Thermal Behaviour of Some New Polyoxometalate Complexes of Ciprofloxacin with Keggin-type Heteropoly Acids

作     者：WANGDun-jia FANGZheng-dong HANDe-yan 

作者机构：DepartmentofChemistryandEnvironmentalEngineeringHubeiNormalUniversityHuangshi435002P.R.China 

出 版 物：《Chemical Research in Chinese Universities》 (高等学校化学研究（英文版）)

年 卷 期：2005年第21卷第3期

页      面：258-263页

核心收录：

学科分类：1007[医学-药学(可授医学、理学学位)] 081704[工学-应用化学] 07[理学] 08[工学] 0817[工学-化学工程与技术] 070303[理学-有机化学] 0703[理学-化学] 10[医学] 

基　　金：SupportedbytheNaturalScienceFoundationofHubeiProvince(No.2003ABA062)andtheNaturalScienceFounda-tionoftheEducationalCommissionofHubeiProvince(No.2003A001) 

主　　题：Thermal decomposition Polyoxometalate complexes Keggin-type heteropoly acids Ciprofloxacin hydrochloride TG/DTA 

摘      要：Four polyoxometalate complexes, (CPFX·HCl)_3H_4SiW_~12 O_~40 , (CPFX·HCl)_3H_3PW_~12 O_~40 , (CPFX·HCl)_3H_3PMo_~12 O_~40 and (CPFX·HCl)_4H_4SiMo_~12 O_~40 , were prepared from ciprofloxacin hydrochloride(CPFX·HCl) reacting with H_nXM_~12 O_~40 ·nH_2O(X=P,Si; M=W,Mo) in an aqueous solution, and characterized by elemental analysis, IR spectrometry and TG-DTA. The IR spectrum confirms the presence of Keggin-type anions of heteropoly acids and the characteristic functional groups of ciprofloxacin. The TG/DTA curves show that their thermal decomposition is a multi-step process including simultaneous collapse of the Keggin-type structure. At first, these compounds had a mass loss of water molecules, then several other mass losses occured due to the decomposition of ciprofloxacin hydrochloride and its fragments with the degradation of Keggin anions. The end product of decomposition is the mixture of WO_3(or MoO_3) and SiO_2(or P_2O_5), identified by X-ray diffraction and IR spectroscopy. The possible thermal decomposition mechanisms of these complexes are proposed. This study exemplified that the thermal stability of the complexes containing tungsten is much better than that of the complexes containing molybdenum.