Theoretical Investigation of the Intrinsic Reaction Path (IRC) of the Methylation of Mono-substituted Aromatic Molecules over Faujasite Catalysts

摘要

In this work, we have investigate the methylation of benzene, toluene nitrobenzene. A methoxide, formed by dehydration of methanol, is the methylating agent. Semi-empirical method, AMl, was applied to calculate the entire IRC of the reactions over the cluster H_3SiO(H)Al(OSiH_3)_3. In all cases one transition state was found along the reaction path, but bond breaking and bond forming do not occur simultaneoulsy. It is possible to rpedict the order of the reactivity between the different sites in an aromatic molecule (ortho, meta or para) and it is suitable to compare the reactivity between different aromatic molecules (toluene and nitrobenzene). In the second part we used the Electronegativity Equalisation Method (EEM) to predict bond breaking and forming and to see if a carbenium ion is formed during the reaction.