3-卤代吲唑水助质子转移反应机理的理论研究(英文)

Theoretical study of reaction mechanism of water-assisted intermolecular transfer of indazole and 3-halogeno-indazole

在密度泛函B3LYP/6-311G^(**)理论水平上,对气相和水相中3-卤代吲唑互变异构体进行几何构型全自由度优化,获得它们在气相和水相中的几何结构和电子结构,PCM反应场溶剂模型用于水相计算。结果显示在气相和水相中,3-卤代吲唑的N_1-H形式比N_2-H形式稳定。探讨了不同的3-取代基团和溶剂化效应对互变异构体的几何结构,能量,电荷分布以及互变异构反应活化能的影响等。进一步研究了3-卤代吲唑水催化质子迁移的反应机理,提出了平面五元环的过渡态结构。

The molecular structures of indazole and 3-halogeno-indazole tautomers were calculated by the B3LYP method at the 6-311G^＊＊ level, both in the gaseous and aqueous phases, with full geometry optimization. The geometry and electronic structure of the tautomers of indazole, 3-halogeno-indazole and their transition states were obtained. The PCM solvate theory model was employed for the aqueous solution calculations. The results of the calculation indicate that the N1-H form of the studied molecule is more stable than that of the N2-H form. The influences of the different 3-halogeno and the solvent effects on the geometry, e^ncrgy, charge and activation energy were discussed. The reaction mechanism of water-assisted intermolecular transfer of indazole and 3-halogeno-indazole was also studied and a five-member cyclic transition state of the water-assisted intermolecular transfer reaction was obtained.