采用密度泛函理论研究了烃类C—H键在醋酸铜催化作用下断裂活性受其相邻基团的影响规律。计算结果表明,与不同基团相连的甲基和次甲基C—H键的催化断裂活性顺序:苯基〉正己基〉环己基;而亚甲基C—H键的催化断裂活性顺序:苯基〉环己基〉正己基。通过对C—H键催化断裂活性的理论分析,发现相邻基团对所连C—H键催化断裂活性的影响与相邻基团在催化剂发生吸附前后的电荷变化量以及空间位阻大小有关。
The density functional theory has been employed to study the influence rule of the catalytic cleavage activity of C—H bond in hydrocarbons affected by adjacent groups under the copper acetate catalyst.The computed results suggested that the order of catalytic cleavage activity of C—H bond of methyl and methyne linking with different adjacent groups was:phenylnhexyl cyclohexyl,while the order of catalytic cleavage activity of C—H bond of methylene was:phenylcyclohexylnhexyl.It was found that the effect of adjacent groups on catalytic cleavage activity of C—H bondwas related with charge value and space steric hindrance of adjacent groups before and after the adsorption on catalyst.