To the solution was dropwise added under cooling at -12° to -14°C a solution of 3-(2-chlorophenyl)-5-methylisoxazol-4-carbonyl chloride, which was prepared from 3-(2-chlorophenyl)-5-methylisoxazol-4-carboxylic acid (1.78 g.) and thionyl chloride (10 ml.), in methylene chloride and then stirred for 5 hours. After the reaction, to the solution was added ice-water, and the resulant mixture was washed with water, dilute phosphoric acid, an aqueous solution of sodium bicarbonate and water in turn, and dried over magnesium sulfate.
