| 摘要 |
PURPOSE:In the liquid-phase halogenation of substituted benzenes, a specific zeolite treated with a lower acylating agent is used as a catalyst to enable high-selectivity production of p-halogenated substituted benzenes which are used as a starting material for medicines and agricultural chemicals. CONSTITUTION:In the production of the compound of formula II (X is halogen) by the liquid-phase halogenation of the compound of formula I (R is lower alkyl, lower alkoxy, halogen), a zeolite which has been treated with a lower acylating agent, preferably acetic anhydride, acetyl chloride, chloracetyl chloride, dichloroacetyl chloride, trifluoroacetic anhydride or methyl orthoformate, has a formulation of SiO2/Al2O3 at a molar ratio of 3-8 and pore sizes of 6-10Angstrom , such as L-type zeolite or Y-type zeolite is used as a catalyst to inhibit the halogenation in the o-position and the polyhalogenation on the benzene nucleus, thus with high selectivity of p-halogenated compound of formula II which has high demand in industry. |
