氨基硫脲与4-氯查尔酮亲核加成-缩合反应的理论研究  

Theoretical Study on Nucleophilic Addition-Condensation Reaction of Thiosemicarbazide with 4-Chlorochalcone

作　　者：倪良[1] 邵怿[1] 张文莉[1] 邵兵[1] 赵琛煊[1] 

机构地区：[1]江苏大学化学化工学院,江苏镇江212013

出　　处：《石油化工》2009年第5期508-514,共7页Petrochemical Technology

基　　金：国家自然科学基金项目(20773109)

摘　　要：对氨基硫脲与4-氯查尔酮亲核加成-缩合反应的反应物和生成物,用量子化学密度泛函方法在B3LYP/6-31G水平上进行了几何构型全优化,从获得的4-氯查尔酮分子中主要原子的Mulliken净电荷,可以推测该化合物具有较高的亲核加成反应活性。对优化后的构型进行了振动分析,得到了不同温度下反应物和生成物的热力学性质,据此计算了相应温度下该反应的焓变、吉布斯自由能变和平衡常数。实验结果表明,在298～1000K内,氨基硫脲与4-氯查尔酮的亲核加成-缩合反应是一个放热反应,吉布斯自由能变为负值,平衡常数很大,说明反应在温和条件下即能自发进行。在此基础上采用含时密度泛函方法计算了分子激发态的电子跃迁能,得到对应激发态的吸收波长,所得结果与文献值基本吻合。Geometric configurations of reactants and products in nucleophilic addition- condensation reaction of thiosemicarbazide （Ⅰ ） with 4-chlorochalcone （ Ⅱ ） were optimized by means of quantum chemistry DFT/B3LYP/6-31G. From the Mulliken atomic net charge of main atoms in I1 ,it could be assumed that the compound was higher in activity for the nucleophilic addition reaction. The thermodynamic properties of reactants and products were obtained via vibration analysis of all optimized geometric configurations, from which the changes of enthalpy, Gibbs free energy and standard equilibrium constants were calculated. The results showed that the nucleophilic additions-condensation reaction ofⅠ withⅡ at 298 - 1 000 K was exothermic and changes of Gibbs free energies of the reaction were all negative. High values of equilibrium constants indicated that the reaction could occur spontaneously under mild conditions. Then, by calculating the energies of electron transitions between excited states of molecules, the UV-Vis data of excited states were obtained. The calculation results agreed satisfactorily with those from literature.

关 键 词：氨基硫脲 4-氯查尔酮 密度泛函理论 亲核加成-缩合反应 

分 类 号：TQ013[化学工程]