Process for the ortho alkylation of phenolic compounds

摘要

The invention relates to a process for the selective ortho alkylation of a phenolic compound having at least one hydrogen atom in the ortho position by catalytic reaction of the phenolic compound with an alcohol in the gas phase. In this process, the reaction of the phenolic compound with the alcohol is carried out at a temperature of 300 to 550 DEG C in the presence of a catalyst containing manganese oxide and one or more additives selected from the group (A) comprising germanium oxide, tin oxide and lead oxide. The catalyst can furthermore contain one or more additives selected from silicon oxide and group (B) comprising alkali metal oxides and alkaline earth metal oxides. The catalyst used in the invention not only has excellent catalytic activity in the selective ortho alkylation of phenols, a continuous stability of the activity, is easy to form and has good mechanical strength, but also leads to effective utilisation of the alcohol.