申请人:Hoechst Aktiengesellschaft
公开号:US05481032A1
公开(公告)日:1996-01-02
A process for the preparation of halogenated benzoic acids of formula (1): ##STR1## in which R.sub.1, R.sub.2, R.sub.3, R.sub.4 and R.sub.5 are hydrogen, fluorine, chlorine or bromine atoms or C.sub.1 -C.sub.6 -alkyl, C.sub.1 -C.sub.6 -alkoxy, nitro, cyano, trifluoromethyl, aidehyde, C.sub.1 -C.sub.4 -alkoxycarbonyl, -SO.sub.2 -C.sub.1 -C.sub.4 -alkyl, -SO.sub.2 -phenyl, -CONH.sub.2, -CON(C.sub.1 -C.sub.4 -alkyl).sub.2, hydroxy, carboxy, -NH.sub.2 or -N(C.sub.1 -C.sub.4 - alkyl).sub.2 groups, at least one of the substituents R.sub.1 -R.sub.5 being one of said halogen atoms, which comprises reacting 1 mol of a benzophenone, asymmetrically substituted on the benzene rings A and B, of general formula (2): ##STR2## in which R.sup.1 -R.sup.10 are as defined above for R.sub.1 -R.sub.5, with about 1 to about 10 mol of an oxidizing agent selected from the group comprising hydrogen peroxide, urea/hydrogen peroxide addition product, an alkali metal peroxide, ammonium, alkali metal or alkaline earth metal peroxodisulfates, pertungstates, perborates or percarbonates, ozone, alkyl- or aryl-percarboxylic acids, alkyl- or aryl-persulfonic acids or persulfuric acid, at temperatures from about -20.degree. to about +100.degree. C.
一种制备卤代苯甲酸的方法,其化学式为(1):##STR1## 其中R.sub.1、R.sub.2、R.sub.3、R.sub.4和R.sub.5分别为氢、氟、氯或溴原子,或者为C.sub.1 -C.sub.6 -烷基、C.sub.1 -C.sub.6 -烷氧基、硝基、氰基、三氟甲基、醛基、C.sub.1 -C.sub.4 -烷氧羰基、-SO.sub.2 -C.sub.1 -C.sub.4 -烷基、-SO.sub.2 -苯基、-CONH.sub.2、-CON(C.sub.1 -C.sub.4 -烷基).sub.2、羟基、羧基、-NH.sub.2或-N(C.sub.1 -C.sub.4 -烷基).sub.2基团,其中至少有一个取代基R.sub.1 -R.sub.5是上述卤素原子之一,包括将1摩尔的苯苯酮,对苯环A和B上不对称取代的一般式(2):##STR2## 中的R.sup.1 -R.sup.10定义如上所述的R.sub.1 -R.sub.5,与约1至约10摩尔的氧化剂反应,所述氧化剂选自包括过氧化氢、尿素/过氧化氢加成物、碱金属过氧化物、铵盐、碱金属或碱土金属过二硫酸盐、过钨酸盐、过硼酸盐或过碳酸盐、臭氧、烷基-或芳基-过碳酸酸、烷基-或芳基-过磺酸或过硫酸,反应温度在约-20℃至约+100℃之间。