METHOD OF OBTAINING KETOACIDS AND THEIR DERIVATIVES Russian patent published in 2014 - IPC C07C51/15 C07C323/52 C07C59/185 C07C319/18 C07C319/20 C07C321/14 

FIELD: chemistry.

SUBSTANCE: invention relates to a method of obtaining α-ketoacids, as well as their derivatives of general formula or , where R¹ stands for either a branched or linear C₁-C₁₈alkyl group and, where R¹ is optionally substituted with -SH or -SCH₃, R² stands for -OR"', where R"' represents a hydrogen atom or a branched or linear C₁-C₈alkyl group, both residues R³ together represent C₂-C₈alkanediyl and together form a ring or both residues R³ and R"' together represent a part of a C₃-C₈alkanetriyl group of general formula -R³(CH-)R"'- and together form a bicyclic group, consisting in the following: a) aldehyde R¹ CHO is subjected to interaction with similar or different thiols of formula R⁴-S-H, where R⁴ stands for a branched or linear, optionally substituted C₁-C₆alkyl group, with obtaining respective dithioacetal, b) formed dithioacetal is subjected in the presence of a strong base to interaction with carbonyl-containing electrophile and further hydrolysis with obtaining α,α-(dithio)carboxylic acid or its derivatives of formula , where R⁵ represents a hydrogen atom or a branched or linear C₁-C₆alkyl group, and residues R⁴ and R¹ have values given above, and c) α,α-(dithio)carboxylic acid or its derivatives of formula are converted by solvolysis carried out at acid catalysis in the presence of at least 1 molar equivalent of water into α-ketoacid or its derivatives of general formula (I) or (II) with the separation of thiols of formula R⁴SH. The invention also relates to an intermediate product of formula .

EFFECT: improved method is environmentally friendly and suitable for implementation on an industrial scale.

14 cl, 12 ex