Synthesis of fluoroalkyl-containing 2-oxyimino-1,3-dicarbonyl compounds and their reaction with hydrazine hydrate

Abstract Reaction of fluoroalkyl-containing 1,3-keto esters and 1,3-diketones and their copper chelates with sodium nitrite gives the corresponding 2-hydroxyiminosubstituted ligands and chelates. 1,1,1-Trifluoro-3-hydroxyimino-4-pheny1-2,4-butanedione reacts with hydrazine hydrate with the formation of 4-hydroxyiminopyrazole. The 1,3-keto ester with a nonafluorobutyl substituent gives the stable 3-nonafluorobutyl-3-dihydroxy-4-hydroxyiminopyrazolidone-5. The similar reaction of ethyl trifluoroacetoacetate oxime leads to a pyrazolidone-5 (which can be dehydrated to 4-oxyiminopyrazolinone-5) and the hydrazide of 4,4,4-trifluoro-2-hydroxyimino-3-dihydroxybutanoate.