METHOD OF PRODUCING 2,7-BIS-[2-(DIETHYLAMINO)ETHOXY]-FLUORENONE-9 DIHYDROCHLORIDE Russian patent published in 2019 - IPC C07C217/22 C07C213/02 

FIELD: chemistry.

SUBSTANCE: invention relates to an improved method of producing 2,7-bis-[2-(di-ethylamino)ethoxy]-fluorenone-9 dihydrochloride, having immunomodulatory properties and a wide range of antiviral action. Method involves sulphonation of fluorene, oxidative hydroxylation of a disodium salt of 2,7-fluorendisulphonic acid, cyclisation of obtained 4,4'-dihydroxydiphenyl-2-carboxylic acid, alkylation of 2,7-dihydroxyfluorenone with hydrochloride with 2-diethylaminoethylchloride to obtain a base which is converted to dihydrochloride. Distinctive feature of the proposed method is that sulphonation of fluorene is carried out with chlorosulphonic acid in molar ratio of fluorene : chlorosulphonic acid of 1:2.2–1:2.3, in temperature range of 0–10 °C with subsequent separation of sodium salt of monosulphofluorene by neutralization of aqueous solution of sulphonation products with sodium hydroxide to pH 8–9 and separation of disodium salt of 2,7-disulfofluorene by evaporation of the obtained filtrate.

EFFECT: method increases output of end product to 36–38 % with respect to initial fluorene and content of basic substance of more than 99 %; wherein amount of by-products is reduced.

1 cl, 2 dwg, 2 ex