The alkylation of phenol with methanol: Conversion of anisole and two-step reaction process on X zeolites

Abstract

The alkylation of phenol with methanol reaction and anisole rearrangement were investigated on NaX zeolite and ion-exchange modified X zeolites with H⁺, K⁺, Cs⁺ and Mg²⁺. The product distribution of anisole rearrangement closely resembles that of the product distribution in the alkylation of phenol with methanol. This indicates that anisole is not only the primary product of the phenol alkylation reaction, but also serves as a key “intermediate” in the conversion of phenol to cresol. Based on the above results, a possible reaction pathway is proposed: the alkylation of phenol with methanol initially generates O-alkylation products, which then undergo rearrangement to form C-alkylation products. By employing a simple layered loading approach, the alkylation of phenol with methanol reaction was divided into two sequential steps. The results provided additional evidence for the feasibility of initially generating O-alkylation products in the alkylation of phenol with methanol and then converting them into C-alkylation products.