Hexafluoroacetone hydrazone

This cyclic octasulfane is stable at 20 °C, and even in a boiling EtOH/CHCls mixture. Related to equation (109) is the reaction of hexafluoroacetone hydrazone with S2CI2, which produces the hexathiepane (CP3)2CS6 (equation 1 lO). ... 

Examples of the oxidation of aliphatic hydrazones are the conversion of acetone hydrazone into 2-diazopropane [386, 392], of hexafluoroacetone hydrazone into 2-diazohexafluoropropane [445], of 4-octanone hydrazone into 4-diazooctane [386], and of the hydrazone of diethyl mesoxalate into diethyl diazomalonate [935] (equations 457 and 458). 

Nitrene insertions into a-amino groups should lead to diaziridines. The only existing report of such a reaction is the photolysis of 2-amino-hexafluoroisopropyl azide (140) which yielded 43% of 3,3-bis (tri-fluoromethyl)-diaziridine (141). The thermal decomposition of 140 yielded only 11% of 141, the main product being hexafluoroacetone hydrazone ... 

Hexafluoroacetone imine distilled slowly during ca. 1 hr. into stirred anhydrous hydrazine cooled below 10°, allowed to warm to room temp., poured rapidly on P2O5, mixed and distilled -> hexafluoroacetone hydrazone (Conversion 53-59%) dissolved in benzonitrile, added dropwise with stirring during 1 hr. under Ng to ice-cooled Pb-tetraacetate and benzonitrile, then stirred 1 hr. at room temp. bis(trifluoromethyl)diazomethane (Y 76-79%). F. e. s. W. J. Middleton and D. M. Gale, Org. Synth. 50, 6 (1970). 

Treatment of perfluoroisopropylamine with sulphur tetrafluoride in the presence of caesium fluoride at 90 °C yields the iminosulphur difluoride (CFslaCF-NiSFa, which can also be prepared from hexafluoroacetone imine and sulphur tetrafluoride. Treatment of (21) with sulphur tetrafluoride in the presence of caesium fluoride at 70 °C yields the iminosulphur difluorides (CFa)aCF-N SFa, (CFa)aaN SFa)a, and (CFa)2(FaS N)C-N S N-C(N SF,)-(CFala, while with phosphorus pentachloride at 0 C it yields the iminosulphur dichloride (CFa)aCCl-N SCla. Similarly, treatment of the trifluoroacetyl compound CFa-CO-N iSFa (formed, together with CaFj-N SFa and CFg-COF by reaction of trifluoroacetamide with sulphur tetrafluoride in the presence of sodium fluoride at 90 °C) with phosphorus pentachloride gives CFa CO N SClj. Treatment of hexafluoroacetone hydrazone with sulphur tetrafluoride in the presence of caesium fluoride at 0— 20 C yields... 

Hexafluoroacetone azine accepts nucleophiles (ROH, RSH, R NH) in positions 1 and 2 to yield hydrazones [27] Phosphites give open-chain products via a skeletal rearrangement [22] Radical addition reactions are also reported [22] Treatment of tnfluoropyruvates with tosylhydrazine and phosphorus oxychlo-ride-pyndme yields tnfluoromethyl-substituted diazo compounds [24] (equation 3)... 

Enamines possessing /7-hydrogen atoms add hexafluoroacetone azine to form transient dipolar azomethine imines 9, as evidenced by low-temperature 19F NMR spectroscopy, which rearrange to hydrazones. If there is no hydrogen atom in the /7-position the betaines cyclize to unstable derivatives 10 of azetidine (equation 7)24. 

About 14 g. (17%) of hexafluoroacetone imine can be recovered during the redistillation step if the receivers for both distillations are cooled to —10° or lower. The yield of the hydrazone is about 67% if the recovered imine is taken into account. 

LTA oxidizes certain hydrazones under basic conditions to the corresponding diazoalkanes. The hydrazone of hexafluoroacetone is a good example ... 

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