Benzoylation of Phenol Ether

Benzoylation under Friedel-Crafts acylation is an important process for the preparation of many industrially valuable chemicals. However, like the acetylation, the use of conventional Lewis acids, for example, AICI3, ZnCl2, and so on, in the homogeneous Friedel-Crafts acylation of arenes entails problems of materials due to corrosion work up and effluent issues. Thus, for benzoylation, as with acetylation, the use of heterogeneous catalysts seems to be an interesting alternative technique to the homogeneous reaction. 

According to Singh et al. [9], benzoylation with benzoic acid did not proceed under the reaction conditions but benzoic anhydride and benzoyl chloride gave the benzophenone. Anhydride was better than acid chloride but for reasons of availability, simplification of process and effluent production we focused attention on the use of benzoyl chloride as reactant for the zeolite catalyzed process. Friedel-Crafts 

The order of activity was HY HBEA HMOR for the dealuminated zeolites but HMOR and HBEA have nearly similar activity. 

The activity of HY increases with dealumination. This was attributed to the generation of mesoporosity during the dealumination and the corresponding ease of diffusion of the reactants and products. Eor HBEA, though, the activity decreases with dealumination because we observed a destructuring of the zeolite. 

We have developed a batch process, catalyzed by HY zeolite, to produce the pharmaceutical intermediate 4-chloro-4 -ethoxybenzophenone (Table 14.6). 

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