Reaction of 6-chlorohexanol (I) with 3-phenyl-5-pyrazolone (II) in the presence of K2CO3 in DMF gives 6-(5-phenyl-3-pyrazolyloxy)hexyl alcohol (III), which affords the crystalline acetoacetate derivative (IV) by esterification of (III) with diketene in the presence of triethylamine. Reaction of (IV) and ammonium carbonate in refluxing methanol gives 3-aminocrotonic acid 6-(5-phenyl-3-pyrazolyloxy)hexyl ester (V). This compound is finally cyclized with methyl 3-nitrobenzylidene acetoacetate (VI) in ethanol.