Selective synthesis of 5-methyl-2-phenylpyridine from carbonyl compounds and ammonia over zeolite catalysts

The vapor-phase cyclization of acetophenone, propionaldehyde, formaldehyde and ammonia was carried out over HZSM-5, H beta and HY zeolites at 400 degr eesC and 0.5 h(-1) weight hour space velocity to synthesize 5-methyl-2-phen ylpyridine. The cyclization activity follows the order: HY > H beta > HZSM- 5. The influence of catalyst modification with a metal ion, temperature. fe ed molar ratio, weight hour space velocity, and activity with time on strea m parameters were studied. The maximum yield of 5-methyl-2-phenylpyridine w as obtained over 3 wt% CoHY zeolite at 400 degreesC.