合成路线1

The reaction of 3-trifluoromethylbenzaldehyde (I) with morpholine (II) and potassium cyanide by means of p-toluenesulfonic acid in refluxing THF gives alpha-(3-trifluoromethylphenyl)-4-morpholineacetonitrile (III), which is condensed with ethyl acrylate (IV) by means of KOH in THF yielding gamma-cyano-gamma-(3-trifluoromethylphenyl)-4-morpholinebutyric acid ethyl ester (V). The cyclization of (V) with hydrazine in refluxing ethanol affords 4,5-dihydro-6-(3-trifluoromethylphenyl)-3(2H)-pyridazinone (VI), which is dehydrogenated by treatment with Br2 in hot acetic acid to give 6-(3-trifluoromethylphenyl)-3(2H)-pyridazinone (VII). The reaction of (VII) with POCl3 at 100 C affords 3-chloro-6-(3-trifluoromethylphenyl)pyridazine (VIII), which is finally cyclized with acetylhydrazine (IX) in refluxing n-butanol.