Optimization for Minodronic Acid Synthesis

The synthesis process of minodronic acid was modified by using orthogonal test method. The results showed that the amount of orthophosphorous acid,phosphorous trichloride and reaction time were the top three factors affecting the product yield. The optimized formula was: the ratio of imidazo [1,2-a] pyridine-3-acetic acid ethyl ester,orthophosphorus trichloride and orthophosphorous acid as 1∶3∶2,with the reaction time of 6 h.