| 摘要 |
An accelerated process for preparing an O-methyl phenol comprising reacting a phenol with dimethyl carbonate in the presence of a catalyst selected from 1,8-diazabicyclo[5.4.0]undec-7-ene; 1,4-diazabicyclo[2.2.2]octane; and dimethylaminopyridine. According to another aspect, the invention provides an accelerated process for preparing an N-methyl heteroaromatic compound comprising reacting an NH-containing heteroaromatic compound with dimethyl carbonate in the presence of a catalyst selected from 1,8-diazabicyclo[5.4.0]undec-7-ene; 1,4-diazabicyclo[2.2.2]octane; and dimethylaminopyridine. According to an additional aspect, the invention provides an accelerated process for preparing a methylated aminophenol comprising reacting an aminophenol having at least one N-H with dimethyl carbonate in the presence of a catalyst selected from 1,8-diazabicyclo[5.4.0]undec-7-ene; 1,4-diazabicyclo[2.2.2]octane; and dimethylaminopyridine. The process of the invention is especially advantageous since the process: (1) utilizes an environmentally friendly methylating reagent, dimethylcarbonate; (2) produces a high yield of the O-methyl phenols, N-methyl aromatic amines, and/or methylated aminophenols, generally 97-100% conversion; and (3) does not require a high-pressure (autoclave) reactor. |
