摘要 |
1,178,779. Phenols and phenyl esters. FARBWERKE HOECHST A.G. 14 March, 1968 [17 March, 1967], No. 12428/68. Heading C2C. A phenyl ester or a mixture of a phenyl ester and phenol are prepared by reacting a mixture of benzene, a saturated aliphatic carboxylic acid and molecular O 2 in the gas or vapour phase in the presence of a compound of a noble Group VIII metal having a maximum stable valency of at most 4. The Group VIII metal compound is a Rh, Ir, Pt, Ru or preferably Pd compound. The reaction is preferably carried out in the presence of an initiator, i.e. a carbonate or carboxylic acid salt of an alkali metal, Zn or Cd; a sodium phosphate or borax. In Examples (1) a catalyst comprising sintered silicic acid impregnated with K and Pd acetates is prepared, placed in a reaction tube at 170‹ C. and 5 atm. and a vaporized mixture of benzene, O 2 , acetic acid and K acetate passed over it to give phenyl acetate and phenol, the phenylacetate being hydrolysed to phenol with steam at 600‹ C.; (2) phenylacetate is obtained by passing benzene, O 2 and acetic acid at 170‹ C. and 1 atm. over a catalyst obtained by impregnating silicic acid with PdCl 2 treating the impregnated carrier with dilute aq. NaOH, washing and drying and depositing K and Cd acetates thereon. |