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采用密度泛函理论(DFT)在B3LYP/6-311G(d,p)水平对锗苯与甲醛和二苯甲酮的Diels-Alder反应的微观机理、势能剖面、取代基效应及溶剂化效应进行了理论计算。结果,所研究的反应均为协同的基元反应,形成Ge-O键的反应中,形成2个新键较大不同步,其它反应的不同步性相对较小。羰基碳原子上的苯基取代基于反应不利,而锗苯分子中锗原子上的C(CH_3)_3与CCl_3取代基则有利。在热力学和动力学上,有锗参与的反应均远比无锗的反应容易,而形成Ge-O键的反应比形成Ge-C键的反应容易,结果与实验一致。四氢呋喃溶剂对所研究反应的势能剖面影响较小。4个形成Ge-O键的反应在四氢呋喃溶剂中进行时,其活化能垒分别为38.03、89.75、29.92和29.87 kJ·mol~(-1)。
The micro-mechanism, potential energy profile, substituent effect and solvation effect of Diels-Alder reaction of germanylbenzene with formaldehyde and benzophenone were studied by density functional theory (DFT) at B3LYP / 6-311G (d, p) The theoretical calculation. As a result, all the reactions studied are coordinated elementary reactions. For the formation of Ge-O bonds, the formation of two new bonds is largely unsynchronized and the other reactions are less asynchronous. The phenyl substitution on the carbonyl carbon atom is unfavorable based on the reaction, while the C (CH_3) _3 and CCl_3 substituents on the germanium atom in the germanium molecule are favorable. In terms of thermodynamics and kinetics, reactions involving germanium are far easier than those of germanium-free reactions, and the reaction of forming Ge-O bonds is easier than that of forming Ge-C bonds. The results are in agreement with the experiment. Tetrahydrofuran solvent has little effect on the potential energy profile of the studied reaction. The reaction energies of the four Ge-O bond-forming reactions in THF were 38.03, 89.75, 29.92 and 29.87 kJ · mol -1, respectively.