Novel Pumice@SO3H catalyzed efficient synthesis of 2,4,5-triarylimidazoles and acridine-1,8-diones under microwave assisted solvent-free path

In the present investigation, new heterogeneous catalyst pumice supported sulfonic acid (pumice@SO3H) was prepared from natural pumice by simple agitation with chlorosulphonic acid. The catalytic performance of a pumice@SO3H was investigated for the synthesis of 2,4,5-triaryl imidazoles and acridine-1,8-diones under microwave (MW) assisted solvent-free condition. The pumice@SO3H was stable and exhibits a good Brunsted acidic character. The beneficial characteristic features observed with this protocol are the recyclability of catalyst, the solvent free approach, the applicability to a wide variety of substrates, good to excellent yields, and easy to use. The catalyst pumice@SO3H with MW has been increased the green chemistry value of this method.