4-苯基嘧啶-2-硫酮互变异构的理论研究

采用B3LYP/6-311 G＊＊方法,计算并考察了4-苯基嘧啶-2-硫酮分子的硫醇式和硫酮式构型进行结构互变质子迁移的两种可能途径：（a）分子内质子迁移,（b）水助质子迁移.计算结果表明,途经（b）所需要的活化能较小,氢键在降低反应活化能方面起着重要作用.Onsager自洽反应场溶剂模型用于水相的计算,并探讨了水溶剂化效应对异构化过程的几何结构和能量的影响.

Theoretical investigation on conformational isomerization and tautomerization of 4-phenyl-2-thiopyrimidine

The processes of the proton transfer between the thione tautomer and the thiol tautomer of 4-phenyl-2-thiopyrimidine were investigated by density functional theory at B3LYP/6-311G** level.The two possible reaction pathways:(a) intramolecular proton transfer;(b) water-assisted intermolecular transfer were investigated.The calculated results showed that the processes(b) has lower activation energies because of the form action of hydrogen-bonded complexes in(b).It is likely that the hydrogen bonds formed in the complexes play an important role in proton transfer processes in the later reaction pathway.Onsager solvate theory model was employed for aqueous solution calculations.