Patent ID: 8853407

Claim:
A process for the manufacture of 4-aryl 1,4-diacyl 1,4-dihydropyridine of the general structure I (STR#1) comprising the steps of a. Mixing 4-arylpyridine, acid anhydride and indium metal in a reactor b. Raising the reaction temperature to about 50°-110° C. c. Maintaining the reaction time ranging from 1 hr to 24 hrs d. Quenching the reaction with water and e. Isolating the final product 4-aryl 1,4-diacyl 1,4-dihydropyridine by crystallization or chromatography Wherein the Ar − functional group is selected from the group consisting of phenyl, alkyl phenyl, aryl phenyl, naphthyl and aryl alkyl, and The R functional group is selected from methyl, ethyl, propyl, butyl, t-butyl, phenyl and benzyl.