SELECTIVE ORTHO-METHYLATION OF PHENOL COMPOUND

摘要

PURPOSE:To carry out the ortho-methylation reaction of a phenol compound using a highly active, highly selective and long-life catalyst containing vanadium oxide, titanium oxide and optionally silicon oxide. CONSTITUTION:A phenol compound of the formula (R1-R4 are H or alkyl) and methanol are subjected to the vapor phase catalytic reaction at 250-500 deg.C using a catalyst containing vanadium oxide, titanium oxide and optionally silicon oxide. The atomic ratios in the catalyst are preferably V:Ti:Si=100:(10-300):(0-70). The catalyst is prepared from oxides of V and Ti, sodium silicate etc. by mixing, precipitation, or evaporation to dryness etc. followed by calcination at 300-600 deg.C. The raw materials are pref. supplied as dilution with water. USE:For example, raw material of a heat-resistant polymer, polyphenylene oxide.