FLUOROLACTONE AND METHOD OF ITS PRODUCTION Russian patent published in 2023 - IPC C07D319/12 C07D317/42 

FIELD: pharmaceuticals.

SUBSTANCE: invention relates to methods of producing a compound described by formula (1) where the two R¹ are the same and each represents a fluorine atom or a C_1-3 perfluoroalkyl group, the method includes step A of reacting the compound represented by formula (2) where R¹ is as defined above, with the compound described by formula (3) where R³¹, R³² and R³³ are the same or different and each represents a hydrogen atom or a C_1-3 alkyl group; and a compound represented by formula (4-1) where R⁴¹, R⁴², R⁴³ and R⁴⁴ are the same or different and each represents a hydrogen atom or an alkyl group, or two of them are optionally linked to each other to form a ring, optionally containing one or more substituents; where the reaction temperature in step A is in the range from -30 to 40° C, as well as methods of obtaining the compound described by formula (5) where R¹ means a fluorine atom or a C_1-3 perfluoroalkyl group. The method includes the stage of obtaining a compound described by formula (1) at stage A and a step C of heating the compound represented by formula (1) obtained in the above step in the presence of at least one fluorine compound (9) selected from the group consisting of the following: a compound represented by formula (9-1) MH_nF_m, where M denotes an alkali metal atom, n is 0 or 1 and the sum of the valences of M and n is equal to m; a compound represented by the formula (9-2) LR⁹¹₄F, where L is a nitrogen atom or a phosphorus atom and R⁹¹ is the same or different and each is a C_1-5 alkyl group; and hydrofluoric acid or a salt thereof to obtain the compound represented by formula (6) where R¹ are as defined above, where the reaction temperature in step C is in the range from 50 to 300°C; step D of reacting a compound of formula (6) with a base to obtain a compound of formula (8) where the reaction temperature in step D is in the range from -50 to 120°C; and a step E of heating the compound represented by formula (8) to obtain a compound represented by formula (5), wherein the reaction temperature in step E is in the range of 100 to 400°C.

EFFECT: development of a method that can be used to obtain fluorolactone from hexafluoropropylene oxide, etc. in one step, while the yield of fluorolactone is high and therefore the purification of fluorolactone can be simplified.

18 cl, 8 ex