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, chromium oxide and optionally silcon 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 a vanadium oxide and a chromium oxide or a manganese oxide, and optionally silicon oxide, to give a phenol compound methylated at the ortho- position. The atomic ratios in the catalyst are preferably V:Cr or Mn:Si=100:(1- 20):(0-70). The catalyst is prepared from oxides of V, Cr and Mn sodium silicate etc. by mixing, precipitation, or evaporation to dryness etc. followed by calcination at 300-600 deg.C. USE:For example, raw material of a heat-resistant polymer, polyphenylene oxide.