【摘要】 利用量子化学的CNDO/2法对一系列二甲苯异构体及其质子络合物进行了计算,结果表明,它们的稳定性具有下列次序: 定域σ-络合物>定域π-络合物>二甲苯异构体>CH₃离域π络合物并且进一步阐明了二甲苯异构体的异构化能、电离能、酸碱性、质子亲合势、亲电子反应等物理化学性质以及间二甲苯在酸性催化剂中的异构化机理。更多还原

【Abstract】 Semiempirical CNDO/2 calculations have been carried out for isomeric xylenes and their protonated-complexes. The results indicate that the stabilities of these compounds are of the following order:localised σ-complex>localised π-complex>Isomeric xylenes>CH₃ delocalised π-complex.Interpretations are given for the physical and chemical properties of xylenes, such as isomeric energy, ionization potential, acidity and basioity, proton affinity, electrophilic reaction, as well as the meohanism of isomerisation of m-xylene on acidic catalyst.更多还原