硫代双烯酮与硫甲醛环加成反应机理的理论研究

采用从头算HF/6-31G^*和密度泛函B3LYP/6-31++G^*^*方法研究了硫代双烯酮与硫甲醛两种可能的环加成反应的机理,并对反应各驻点进行了电子密度拓扑分析研究.结果表明,这两个生成不同四元杂环产物的平行反应均为有一两性离子中间体的分步反应.两个反应均较易进行,但反应(1)更容易一些,结果与实验一致.

Theoretical studies on the mechanism of the cycloaddition reaction between thioketene and thioformaldehyde

Ab initio HF/6 - 31G* and density functional theory (DFT) B3LYP/6 - 31 G* * have been used to study the mechanism of the cycloaddition reaction between thioketene and thioformaldehyde. These two reactions that give different four-membered heterocyclic products; both proceed via a two-step mechanism involving a zwitterionic intermediate. Both processes proceed easily, but reaction (1) is more favorable. In addition, Bader type electron density topological analysis was used to study the electronic structures of stationary points for reactions (1) and (2) .