M. D. Bargamova

α-Hydrohexafluoroisobutyryl fluoride — A new system with a labile hydrogen atom

α-Hydrohexafluoroisobutyryl fluoride reacts with triethylamine to form the salt of a stable carbanion, capable of being alkylated, forming homologs.

Perfluorodimethylketene and perfluoromethacrylic acid Communication 1. Hexafluoroisobutyryl chlorides from fluorinated ethers

1. When the appropriate ethers containing fluorinated groups react with sulfuric acid or aluminum halides, 2-hydro- and 2-halo-hexafluoroisobutyryl halides are obtained. 2. It was shown that in the fluorocarbonyl group of the acid fluorides obtained fluorine can be smoothly replaced by chlorine or bromine by the action of the appropriate aluminum halide. 3. Perfluorodimethylketene is formed in the pyrolysis of perfluoroisobutenyl methyl ether.

Fluorine-containing allenes

The reaction of tetrakis(trifluoromethyl)allene with thiophenol and ethyl mercaptan was studied. The corresponding thioether is formed in the reaction with thiophenol, while the reaction with ethyl mercaptan gives a complex mixture of products.

Communication 1. Reaction of tetrakis(trifluoromethyl) allene with nitrogen oxides and nitrosyl chlorides

1. The radical addition reactions of NOCl, Cl2, N2O4, and N2O3 to tetrakis(trifluoromethyl)allene were studied. 2. The reaction of tetrakis(trifluoromethyl)allene with NOCl leads to a number of linear aliphatic carbonyl compounds, which are obtained as the result of eliminating one CF3 group. The allene under the influence of either N2O4 or N2O3 undergoes complex transformations, as a result of which 1-N-oxy-3,3,5,5-tetrakis(trifluoromethyl)-4-keto-1,2-diazine and 3,3,5,5-tetrakis(trifluoromethyl)-4-keto-l,2-diazine are obtained.

Reactions of hexafluoropropene with methanol at atmospheric pressure

1. In the reaction of hexafluoropropene with methanol in presence of sodium methoxide, apart from the already known products of the addition of methanol at the double bond and the replacement of one of the fluorine atoms, 2H-pentafluoro-1,1-and -1,3-dimethoxypropanes are formed. 2. By the reaction of anhydrous sodium alkoxides with hexafluoropropene alkyl pentafluoropropenyl ethers are formed.

Some properties of halides of fluorinated acids

1. Conditions were found for the production of perfluorodimethylketene in good yields by the dehalogenation ofα-haloperfluoroisobutyryl halides with zinc in ethyl acetate. 2. The interaction ofα-chloroperfluoropropionyl chloride with zinc, leading to the production of a low yield of a mixture of perfluoroacrylyl and tetrafluoropropionyl fluorides, was investigated. 3. Perfluoroacrylyl halides were produced by dehalogenation of α,β-dibromoperfluoropropionyl halides. In this case there is a side reaction of cleavage of the ethers by the acid halides, leading to esters of fluorinated acids. 4. The cleavage of ethers by perfluoroacrylyl halides in the presence of zinc salts can be used as a preparative method for obtaining alkyl perfluoroacrylates.

The reaction ofα-H-Fluorocarboxylic acids with phosphorus pentoxide

Depending on the reaction conditions, fluoroacids containing a hydrogen atom in theα-position to the carboxy group react with phosphorus pentoxide to give either anhydrides or products of their further conversion.

Bistrifluoromethylketene Communication 7. Structure of the dimer

1. Unlike other known ketenes, bistrifluoromethylketene forms a linear dimer under the action of triethylamine. 2. A new reaction was discovered: the linear dimerization of functional derivatives of perfluoromethacrylic and (difluoromethylene)malonic acids.

Acid halides of tetraflu-opropionic acid

1. The acid halides of tetraflu-opropionic acid were obtained by reacting theβ-hydroperflu-opropyl methyl andβ-hydroperflu-opropyl ethyl ethers with aluminum chl-ide. 2. The acid halides of anα-haloperflu-opropionic acid were synthesized by the direct chl-ination of tetraflu-opropionyl chl-ide and by the bromination of a mixture of tetraflu-opropionyl flu-ide and triethylamine.

Action of triethylamine on 3,3,3-trifluoro-2-(trifluoromethyl)propionyl fluoride

1. It was shown that 3,3,3-trifluoro-2-(trifluoromethyl)propionyl fluoride dimerizes under the action of triethylamine. 2. An investigation was made of the properties and reactivity of the dimer and a number of derivatives of α,β-unsaturated γ-H-polyfluorinated acids.