1,4-dihydropyrazol-5-one

Conditions: temp:80.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: The method of the invention is then used to convert the 1,2,4-oxadiazole to the 2-pyrazolin-5-one. As previously described, the method comprises forming a liquid reaction system of a base catalyst and the 1,2,4-oxadiazole in an organic liquid reaction medium and heating the reaction system to a temperature sufficient to cause the 1,2,4-oxadiazole to be rearranged to the 2-pyrazolin-5-one, e.g., heating a solution of potassium hydroxide and 2-(5-methyl-1,2,4-oxadiazol-3-yl)-2',4',6'-trichloroacetanilide in anhydrous ethanol under reflux at a temperature of 80° C. for 8 to 14 hours to yield 3-acetamido-1-(2,4,6-trichlorophenyl)-2-pyrazolin-5-one, i.e., ##STR7## the method comprises forming a liquid reaction system of a base catalyst heating the reaction system to a temperature sufficient

Conditions: temp:80.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: The method of the invention is then used to convert the 1,2,4-oxadiazole to the 2-pyrazolin-5-one. As previously described, the method comprises forming a liquid reaction system of a base catalyst and the 1,2,4-oxadiazole in an organic liquid reaction medium and heating the reaction system to a temperature sufficient to cause the 1,2,4-oxadiazole to be rearranged to the 2-pyrazolin-5-one, e.g., heating a solution of potassium hydroxide and 2-(5-methyl-1,2,4-oxadiazol-3-yl)-2',4',6'-trichloroacetanilide in anhydrous ethanol under reflux at a temperature of 80° C. for 8 to 14 hours to yield 3-acetamido-1-(2,4,6-trichlorophenyl)-2-pyrazolin-5-one, i.e., ##STR7## the method comprises forming a liquid reaction system of a base catalyst heating the reaction system to a temperature sufficient

Conditions: temp:80.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: The method of the invention is then used to convert the 1,2,4-oxadiazole to the 2-pyrazolin-5-one. As previously described, the method comprises forming a liquid reaction system of a base catalyst and the 1,2,4-oxadiazole in an organic liquid reaction medium and heating the reaction system to a temperature sufficient to cause the 1,2,4-oxadiazole to be rearranged to the 2-pyrazolin-5-one, e.g., heating a solution of potassium hydroxide and 2-(5-methyl-1,2,4-oxadiazol-3-yl)-2',4',6'-trichloroacetanilide in anhydrous ethanol under reflux at a temperature of 80° C. for 8 to 14 hours to yield 3-acetamido-1-(2,4,6-trichlorophenyl)-2-pyrazolin-5-one, i.e., ##STR7## the method comprises forming a liquid reaction system of a base catalyst heating the reaction system to a temperature sufficient