METHOD OF OBTAINING DIALKYLPHOSPHITES Russian patent published in 2014 - IPC C07F9/141 

FIELD: chemistry.

SUBSTANCE: invention relates to a method of obtaining dialkylphosphites and can be applied in the chemical industry, including obtaining 2-phosphonobutyl-1,2,4-tricarboxylic acid. In the claimed method a P-O component is added simultaneously with TAP or separately from it into a R′OH-containing reaction mixture, and the reaction mixture is brought to a temperature in the range from 40°C to 180°C during the period of time from 10 minutes to 10 hours, where the P-O component contains from 1 to 6 P-O-P bonds in a molecule at the stage of interaction of the R'OH mixture and the P-O component, expressed in molar ratios R'OH:P-O at least from 1:1 to 6:1, where R′ is selected from alkyl groups, which have from 1 to 20 carbon atoms in a branched or linear configuration; and TAP - P(OA)₃ [trialkylphosphite], where A stands for linear or branched alkyl groups, which have from 1 to 20 carbon atoms; where the minimal number of TAP moles per the P atom in the P-O molecule, required for the said method, "z", is determined by formula z=2n-m, where: n stands for the number of P atoms in the P-O molecule, and m stands for the number of P-O-P bonds in the P-O molecule. 2-phosphonobutyl-1,2,4-tricarboxylic acid is obtained from dialkylphosphite, obtained by the claimed method, by its interaction with methylmaleate with further reaction with methylacrylate in the presence of sodium methylate and hydrolysis of ester groups with water in the presence of hydrochloric acid.

EFFECT: claimed is an effective method of obtaining dialkylphosphites and 2-phosphonobutyl-1,2,4-tricarboxylic acid.

14 cl, 5 ex