METHOD OF OBTAINING HIGHLY FLUORINATED CARBOXYLIC ACIDS AND THEIR SALTS Russian patent published in 2015 - IPC C07C51/353 C07C231/12 C07C233/05 C07C233/06 C07C51/367 C07C53/21 C07C67/347 C07C69/63 C07C69/708 C07C235/06 C07C59/135 C07C67/38 

FIELD: chemistry.

SUBSTANCE: invention relates to a method of obtaining highly fluorinated carboxylic acids and their salts, as well as substances-precursors, which includes an impact on a highly fluorinated olefin, which has the general formula (I): R_f-(O)_n-(CF₂)_m-CF=CF₂ of a formic acid derivative in accordance with the general formula (II): HCOR in the presence of a radical initiator to form a substance-precursor of carboxylic acid in the form of O-ethers, S-ethers or an amide adduct of the general formula (III): R_f-(O)_n-(CF₂)_m-CFH-CF₂-COO and, optionally, in case of an acid obtaining, hydrolysis of an adduct of formula (III) to form carboxylic acid or its salts with the general formula (IV): R_f-(O)_n-(CF₂)_m-CFH-CF₂-COO^-M⁺, where in formulas (II) and (III) R represents a residue O^-M⁺, S^-M⁺, OR' or SR' or NR'R", where R' and R" are independent on each other linear or branched or cyclic aliphatic residues, which contain at least one carbon atom and which do not have an alpha-H-atom, where the alpha-H-atom represents a hydrogen atom, bond with a carbon atom, bound with O, S or N in groups OR', SR' or NR'R", and where in formulas (I), (III), (IV) R_f represents H, either a perfluorinated or fluorinated linear or branched alkyl residue which can contain one or several catenary oxygen atoms, and n constitutes 1 or 0, m represents a number from 0 to 6, and M⁺ represents a cation.

EFFECT: method makes it possible to obtain target compounds with the high output.

8 cl, 7 ex