Patent ID: 7262296

Claim:
A process for the preparation aryl alkenoic acid heterocyclic amides of the chemical formula 1, wherein n=1 or 2, X=O or N—CH 3 and wherein R=linear or branched C 1 to C 5 alkyl chain, the process comprising the steps of: (a) reacting aldehyde of general formula (5) with alkyl magnesium halide with constant stirring at an ambient temperature in an anhydrous ethereal solvent to produce corresponding phenyl ethanol of general formula (4), (b) treating the compound of general formula (4) with dimethyl formamide and phosphorous oxychloride at 0° to 10° C. for 20-40 hours, working up the reaction mixture by adjusting the pH of the solution and isolating the product of general formula (3) by using conventional method, (c) reacting the compound of general formula (3) with witting reagent in presence of a base at a temperature range of 15-80° C. in an ethereal solvent for a period of 1-80 hours to get the corresponding carboxylic ester, (d) hydrolysing the ester of step (c) with strong alkali solution followed by acidification of the reaction mixture to produce the corresponding carboxylic acid of general formula (2), (e) reacting compound of step (d) of general formula (2) with thionyl chloride in presence of an organic solvent at a temperature in the range of reflux temperature of 70° C.-80° C., removing the solvent to obtain the corresponding acid chloride, (f) reacting the acid chloride of step (e) with heterocyclic amine in an inert organic solvent at a temperature in the range of 0 to 50° C. for 1 to 16 hours, isolating the product by purifying the reaction mixture to obtain product of formula 1