SU687079A1 - Method of obtaining alkylphosphonic acids - Google Patents

Description

(54) METHOD FOR OBTAINING ALKYLPHOSPHONIC ACIDS

one

This invention relates to the chemistry of organophosphorus compounds with a C-P bond, and specifically to a process for the preparation of alkylphosphonic acids of the formula:

HE

“-

where R is alkyl, which can be used as surface active substances, inhibitors, corrosion, plasticizers, lubricant additives and polymers for imparting fire resistance.

 A known method for producing phosphonous acids by oxidizing primary phosphines with hydrogen peroxide when heated to 1.

In this method, phosphonic acid is formed as a by-product.

The closest in technical essence and the achieved result to the proposed method is to obtain alkylphosphonic acids, is that hypophosphorous acid is attached to olefins in the presence of organic peroxides and sulfuric acid when heated to 65-85 with organic solvent in an inert atmosphere gas 2.

The disadvantage of this method is the duration of the process (4-5 hours), as well as the fact that it is possible to obtain only a mixture of alkylphosphonous and dialkylphosphonic acids, and it is very difficult to select pure alkylphosphonous acids from the mixture,

The aim of the invention is to process the process and increase the yield of the target product.

five

The goal is achieved by the method of obtaining alkylphosphonic acids, which consists in the fact that hypophosphorous acid is attached to olefins in the presence of a peroxide initiator (hydrogen peroxide) and mineral acid when heated, preferably to 55-75 s in an organic solvent medium in an inert gas atmosphere . 5 The hallmark of the method. is the use of hydrogen peroxide as a peroxide initiator.

Claims (2)

The method allows using 0 available peroxide initiator (hydrogen peroxide) and shortens the process time up to 1-3 hours. In addition, the reaction proceeds purposefully and results in obtaining individual phosphonic acids without dialkylphosphonic acid impurities with a yield close to the quantity. As a mineral acid, for example, hypophosphorous or sulfuric acid can be used. Hypochlorous acid, used Suitable for the production of alkylphosphonic acids, it can be obtained directly before synthesis from a salt of phosphoric acid and sulfuric acid. Example 1. Heptylphosphonist acid. 14.1 ml (0.1 mol) of heptane-1 and 40 dioxane are added to 8.2 g (0.124 mol) of hypophosphorous acid. A solution of 1.7 g of 30% hydrogen peroxide (0.015 mol) in 5 ml of dioxane is added dropwise in an atmosphere of inert gas at 70-75 for 1.5 hours. After that, the solvent is rtgrn under the vacuum of a water jet. The heptylphosphonic acid is extracted with benzene, the benzene extra is washed with water, the benzene is distilled off. Yield 16.1 g (98.3%), crude product. Bp 170 s mm Hg / 10 p |, ° 1,4556.S Equivalent titration: found 163, calculated 164. Similarly, from 12.5 ml (0.1 mol) of hexene-1, hexylphosphonic acid is obtained with a yield of 96%, bp 155 ° C / 10, p 1.4550 Equivalent titration: found 152, calculated 150. From 12.1 ml (0.1 mol) of 4-methylpethen-1, 4-methyl-amylphosphonitic acid is obtained with a yield of 97%, bp . mmHg /. lO, n | Jl, 4532. Titration equivalent: found 149, calculated 150. Example 2. Hexylphosphonist acid 66.5 g (0.725 mol) of sodium hypophosphite monogram are mixed with 30 ml of water while cooling to 15 ° added 25 ml (0.46 mol) of concentrated sulfuric acid . 120 ml of dioxane and 62.5 ml (0.5 mol) of hex-1 are added to the images of the suspension suspension. During 50 minutes at 65-70s, the reaction mixture was added dropwise with 8.5 g of a solution of 30% (0.075 mol of hydrogen peroxide in 15 ml of dioxane. The reaction was carried out in an inert gas atmosphere. After the end of the stirring, the mass was stirred for an additional 1 min., Inorganic precipitate filtered off and washed on the filter with a small amount of dioxane. The solvent is distilled off in a water jet vacuum pump. Hexyl phosphonic acid is extracted with benzene. The benzene extract is washed 4-5 az with small portions of water (until the ions are removed), the benzene is distilled. oropno benzene. Yield 70 g (93.4%) of hexyl phosphonic acid. boil. 155-160s mm Hg / 10, D 1.4550. Equivalent titration: 150 calculated. Example 3. Heptylphosphonist and acid 13.3 g ( 0.125 mol) of sodium hypophosphite monohydrate is mixed with 6 ml of water and 5 ml (0.092 mol) of concentrated sulfuric acid are added with cooling to 15 ° C. 40 ml of dioxane, 14.1 ml (0.1 mol) of heptene-1 are added to the suspension. 1.5 h at 70-75 ° C in an inert gas atmosphere, a solution of 1.7 g of 30% hydrogen peroxide in 5 ml of dioxane is added dropwise to the reaction mass. After this, the reaction mass is stirred for another 30 minutes, cooled, the inorganic precipitate is filtered off and washed on the filter with a small portion of Dioxane. The solvent is distilled off in a water jet vacuum. The heptylphosphonic acid is extracted with benzene; The benzene extract is washed 4–5 times with small portions of water until the sol sol disappears. The benzene is distilled off, the reaction product is azeotropically dried with benzene. The yield of 16.2 g (98.8%). Heptylphosphonic acid, bp, 170 mm Hg, Art., / 10-, Ti |, l, 4556. Titration equivalent: found 1620, calculated 164, Example 4. 4-methyl-amylphosphonate acid, 12.7 g (0.12 mol) of sodium hypophosphite monohydrate are mixed with 6 ml of water, while cooling to 15c, 4 ml (0.073 mol) of concentrated is added sulfuric acid. 40 ml of dioxane and 12.1 ml (0.1 mol) of 4-methylpentene-1 are added to the suspension. 1.7 g of a solution of 30% (0.015 mol) hydrogen peroxide in 5 ml of dioxane is added dropwise to the reaction mass in the atmosphere of an inert gas for 1 hour at BB-BOC. The mixture is stirred for another 30 minutes at the same temperature. It is then cooled, the inorganic precipitate is filtered off, the solvent is distilled off in a water jet pump vacuum, 4-methyl-amylphosphonic acid is extracted with benzene, and the benzene extract is washed with small portions of water until the ions disappear. The benzene is distilled off, the reaction product is azeotropically dried with benzene. Output 14.7 g (98%), t, bale, 130-135 С mm Hg, Art. , p. 1.4532, Equivalent titration: found 149, calculated 150, Example 5. Cyclohexylphosphonist acid. 13.3 g (0.125 moL) of sodium hypophosphite monohydrate are mixed with a ml of water and, while cooling to 15 ° C, 5 ml (0.09 L) of concentrated sulfuric acid are added. 40 ml of dioxaia, 10.15 ml (0.1 mol) of cyclohexene are added to the suspension. During 2.5 hours at 75 in an inert gas atmosphere, 1.7 g of a solution of 30% (0.015 mol) hydrogen peroxide in 10 ml of dioxane is added to a mixture of the reaction mass. The mixture is stirred for another 30 minutes at 75 ° C, then cooled, the inorganic precipitate is filtered off, the solvent is distilled off in a vacuum of a water-jet pump. The cyclohexylphosphonic acid is extracted with benzene, the benzene extract is washed with water, the benzene is distilled off, the reaction product is dried with azeotropic benzene. The output of 13.5 g (91.2%) of cyclohexylphosphonic acid, so kip. 205 with mm Hg / Yu t. 1,44981. Equivalent titration: found 149, calculated 148. Claim 1. Invention of the preparation of alkylphosphonic acids by addition of a hypophosphorous acid to olefins in the presence of a peroxide initiator and mineral acid when HCl is heated in an organic solvent in an inert gas atmosphere, characterized in that, in order to simplify the process and increase the yield of the target product; hydrogen peroxide is used as the peroxide initiator. 2. Method POP.1, distinguished by the fact that heating is carried out up to 55-75 C. Sources of information taken into account during the examination 1.Purdela D., Ylpchanu R. - Chemistry of organic compounds of phosphorus, M., Chemie 1972, p. 165. 2. Author's certificate 525700, cl. C 07 F 9/48, ii974, ROTOTIP).