DE2015068B2 - ALPHA-SUBSTITUTED PHOSPHONO Amber Acids - Google Patents

Description

Examples of R are methyl, ethyl, propyl, Isopropyl, butyl and sea-butyl radical, furthermore the AUyI- and called the methallyl residue

R ₁ preferably denotes the methyl and ethyl radicals. The alkylation or substitution of the tetraalkyl phosphonosuccinate is carried out in such a way that the teiraalkyl phosphonosuccinate is first metalated by z. B. with stoichiometric amounts of alkali metals ¹ !, Such as lithium or potassium and especially sodium, or with stoichiometric amounts of alkali metal compounds that are acidic with CH. Compounds capable of forming salts, e.g. B. alkali amides, such as sodium amide, alkali hydrides, such as sodium hydride, or alkali metal alcoholates, such as sodium methylate, sodium ethylate or potassium tert-butoxide, and then the alkali phosphonosuccinic acid tetraalkyl ester compounds obtained with the usual alkylating agents, such as alkyl halides, e.g. B.

Methyl bromide, methyl iodide, ethyl chloride, allyl bromide, methallyl chloride, butyl iodide, cyclohexyl bromide, benzyl chloride, dialkyl sulfate. * 5 such as methyl sulfate and ethyl sulfate alkyl sulfonic acid esters, such as
P-toluenesulfonic acid esters, trialkyl phosphates, such as trimethyl phosphate or triethyl phosphate, are allowed to react. The phosphonosuccinic acid tetraalkyl esters are also suitable as alkylating agents.

The metalation and alkylation of the Phosphonobernsteinsärre tetraalkyl esters is preferably carried out in inert organic solvents such as aromatic hydrocarbons, e.g. B. benzene, toluene, xylene or ethers, such as ether, tetrahydrofuran, made. The metallization usually has a positive heat tint. It may therefore have to be cooled. The alkylation is carried out at temperatures between 10 and 18O ⁰ C, preferably 20 and 14O ⁰ C, carried out the resulting "-substituted phosphonosuccinic acid tetraalkyl ester-can then be purified by vacuum Destillationn.

When alkylating or substituting the tetraalkyl phosphonosuccinate esters with tetraalkyl phosphonosuccinic esters, mixtures of trialkyl phosphonosuccinic esters, tetraalkyl esters, trialkyl α-alkyl phosphonosuccinic esters and tetraalkyl esters or their sodium salts are obtained. The alkylation is carried out in such a manner that phosphonosuccinic acid tetraalkyl ester-be reacted with alkali metal alkoxides or alkali metals at 80- 17O ⁰ C, preferably 100-150 ⁰ C. The amount of alkali metal alcoholate or alkali metal is decisive for the proportion of a-alkyl-phosphonosuccinic acid alkyl ester in the mixtures. When using 0.5 mole of alkali metal (alcoholate) per mole of phosphonosuccinic acid tetraalkyl ester, a mixture is obtained which consists of about 50% of α-alkylated and about 50% of non-alkylated phosphonosuccinic acid alkyl esters. If one mole of alkali metal (alcoholate) is used per mole of tetraalkyl phosphonosuccinate, the mixture consists essentially of -alkylated trialkyl phosphonosuccinate. The α-alkyl-phosphonosuccinic acid alkyl esters obtained are then saponified by heating with concentrated hydrochloric acid. The saponification can also be carried out in two stages by

the esters first with dilute aqueous hydrochloric acid while distilling off the liberated alcohol partially saponified and then the saponification is completed by adding concentrated hydrochloric acid

The α-alkyl-phosphonosuccinic acids are dissolved in hydrochloric acid after half of the saponification. After the hydrochloric acid has been distilled off in vacuo at temperatures up to about 140 ³ C, the anhydrous α-alkyl-phosphoiiisuccinic acids are obtained, which are viscous when heated and either crystallize or solidify glassy when cold.

The α-substituted phosphonobesinic acids of the invention of formula I are characterized by an excellent ability to form complexes for alkaline earth metal ions the end. They are therefore excellent as: s sequestrants, e.g. B. in cleaning agents, suitable how they are used in the food industry for bottle washing. The ability to form complexes of the «-substituted phosphonosuccinic acids according to the invention is significantly higher than that of the phosphorus compounds previously used as sequestering agents. So the softening factor is which is a measure of the sequestering ability of a compound for:

25th

and made up to 1000 ml

Na hexamethaphosphate hai. so at a consumption 10.0 ml CaCIr solution has a softening factor of 100.

The -substituted phosphonosuccinic acids according to the invention also have the advantage that the Saturation concentration of their poorly soluble calcium salts is not achieved with the water hardness occurring in practice, d. H. no stone formation occurs; on the other hand, the saturation concentration of the poorly soluble calcium salts of the known phosphoric acid or phosphonic acid sequestering agent! already achieved with the usual water hardness

The table below shows the limit calcium concentrations (given in ° dH) for a range of phosphoric and phosphonic acids:

link Ent- ' was standing hardening the factor Technology ³⁵ ß- phosphonobutyric acid 26th ß- phosphonopropionic acid 30th 1 -phosphonopropari-23-di- 58 carboxylic acid Sodium hexametaphosphate 100 invention 1,2-diphosphonosuccinic acid 100 Phosphonosuccinic acid 100 Hydroxyethane diphosphonic acid 280 Nitrilotrismethylene phosphonic 309 acid «-Methylphosphonobernstein- acid 500

The softening factor was determined as follows:

Reagents
1) soda solution

100 g CaIc. Soda p. A. are with least. Dissolved water and made up to 1000 ml

2) calcium chloride solution
37.92 g CaCl ₂ · H ₂ O are dissolved with distilled water

55

Performing the titration

100 ml of the 1% sample solution in dist. Water are adjusted to pH 13.0 with sodium hydroxide solution or HCl. 2 ml of soda solution are added. _{The CaCl 2} solution is added dropwise with constant stirring until a cloudiness can be seen which no longer dissolves within a minute. The calcium chloride solution was adjusted so that sodium hexametaphosphate resulted in a consumption of 10.0 ml of calcium chloride solution. The consumption of 0.1 ml CaCl2 solution corresponds to a softening factor of 1

link CalcJum- was standing Borderline the focus technology trations Hydroxyäthandisphosphon- 10 ° dH invention acid Phosphonosuccinic acid 19 ° dH Nitrilotrisr.iethylenphosphon- 24 ° dH acid Na hexametaphosphate 25 ° dH a-methylphosphono 78 ° dH succinic acid

The -substituted phosphonosuccinic acids according to the invention can be used as free acids or in the form their alkali or amine salts in the cleaning agents, which also contain the usual additives such as Wetting agents, emulsifiers, defoamers, organic builders, bleaching agents! and disinfectants can be used.

example 1

To the suspension of 23 g (1 mol) of sodium in 300 ml of toluene, with vigorous stirring and good Cooling at 20-25 ° C. 254 g (1 mol) of tetramethyl phosphonosuccinate dripped. A clear yellow solution of tetramethyl sodium phosphonobernic acid is formed in toluene.

126 g (1 mol) of dimethyl sulfate are added dropwise to this solution at 10-40 ° C. over a period of about 25 minutes, while stirring and cooling. The reaction mixture is then stirred for a further 1 hour a bottom temperature of about 6O ⁰ C the solvent removed Subsequently, the crude "-methyl-phosphonosuccinic acid tetramethylester fractionally distilled yield: 172 g (65% of theory); Bp .: 127 - 130 ° C / l Torr.

The a-methyl-phosphonosuccinic acid tetramethyl ester obtained in this way is with 100 ml of dilute hydrochloric acid (2 mol HCl / liter) for 18 hours while distilling off of the methanol formed during the saponification is heated to boiling temperature. The saponification mixture is then added 150 ml of concentrated hydrochloric acid (12 mol HCl / liter) are added and the mixture is continued for a further 18 hours Heated to reflux temperature. The reaction solution is then evaporated to dryness in vacuo (maximum Sump temperature: 120 ° C) and dilute with water to a 50% solution!

5
Example 2

254 g (1 mol) of phosphonosuccinic acid tetramethyl ester are stirred at 20-25 ° C with a Solution of 54 g (1 MqI) of sodium methylate in 330 ml Methanol added. After adding 300 ml of toluene, the solvent mixture is in> Vacuum distilled at 15-25 ° C so far that the sodium phosphonosuccinic acid tetramethyl ester barely still in solution. After a further addition of 300 ml of toluene and again distilling off the solvent mixture in vacuo, the sodium salt is almost in place methanol-free toluene solution.

140 g (I mol) of trimethyl phosphate are added dropwise at 20-30 ° C. to the solution of the sodium phosphonosuccinic acid tetramethyl ester obtained in this way, while stirring and cooling, within 30 minutes. The reaction mixture is then stirred for a further 2 hours. Then, the atisgeschiedene sodium dimethyl phosphate is filtered off and the filtrate up to a bottom temperature of 60 ⁰ C freed from the solvent by distillation in vacuo. The crude product is then purified by distillation. Yield: 195 g; Bp: 126-13-1 Torr.

According to the gas chromatogram, the distillate consists of 86% a-methyl-phosphonosuccinic acid tetramethyl ester and 10% tetramethyl phosphonosuccinate.

The distillate is heated to reflux temperature with 400 ml of concentrated hydrochloric acid (12 mol / liter) for 24 hours. The weak acidic reaction solution is then evaporated to dryness in vacuo to diluted to a sump temperature of 120 ⁰ C and then with water to give a 50% solution

Example 3

To the solution of 1 mol of sodium phosphonosuccinic acid tetramethyl ester in 200 ml of toluene, which as in the example! 121 g {1 mol) of allyl bromide are added dropwise with stirring and cooling at 20-25 ^° C. within about 20 minutes. After the addition of allyl bromide is complete, stirring is continued for 3 hours vacuum up to a bottom temperature of 60-70 ⁰ C the solvent was evaporated, the crude product is distilled Ausbeule Subsequently, 246 g (84% of theory); Bp: 133-140 ° C / l Torr.

According to the gas chromatogram, the product contains 92% «-allylphosphonosuccinic acid tetramethyl ester.

The ester is saponified in the manner indicated in Example 1.

Example 4

The solution of 27 g (0.5 mol) of sodium methylate dissolved in 180 ml of methanol is added dropwise to 254 g (1 mol) of tetramethyl phosphonosuccinate over about 90 minutes at 100 ° C. with stirring and heating Methylatzugabe the reaction mixture is stirred for 30 minutes at 100 ⁰ C then allowed the reaction product at 50 ° C to cool and added dropwise with stirring 42 ml of concentrated hydrochloric acid (12 mol HCl / liter). The sodium chloride which separates out is then filtered off. The filtrate is saponified in the manner described in Example 1. 360 g of a 50% strength aqueous solution of a 1: 1 mixture of phosphonosuccinic acid and α-methyl-phosphonosuccinic acid are obtained.

Example 5

To 254 g (1 mol) of tetramethyl phosphono succinate the solution of is added dropwise at 130.degree. C. with stirring and heating within 30 minutes 40.5 g (0.75 mol) of sodium methylate dissolved in 270 ml of methanol. The evaporating methanol is during

ίο the dropping is distilled off in a water jet vacuum The reaction mixture is then stirred for a further 30 minutes at 135 ° C. under normal pressure After cooling to about 50 ° C., the reaction product is concentrated with 63 ml (0.75 mol)

15 ' hydrochloric acid is added and the precipitated sodium chloride is filtered off. The filtrate is saponified in the manner described in Example 1

After concentrating the saponification solution in Vacuum obtained from 50 g of a 1: 3 mixture Phosphono succinic acid and Λ-methyl-phosphono succinic acid.

Example 6

In 254 g (1 mole) at 100 ° C heated-phosphonosuccinic acid tetramethylester be entered g within 30 minutes at 100 ^C C 27 g (0.5 mol) of solid sodium methoxide with stirring and cooling in portions of 3.5. Before each addition, it is waited until the temperature of the mixture has ^{fallen back to 100 °} C. After the addition has ended, the reaction mixture is stirred for a further 1 hour.

The reaction mixture is worked up in the manner described in Example 5 1: 1 mixture of phosphonosuccinic acid and Λ-methyl-phosphonosuccinic acid.

Example 7

11.5 g (0.5 mol) of sodium are introduced in portions into the boiling mixture of 254 g (1 mol) of tetramethyl phosphonosuccinate and 16 g of methanol over the course of 1 hour. The sodium melts and reacts with the mixture. After the last addition of sodium, the mixture is stirred at 120 ^° C. for a further 1 hour

The reaction mixture is worked up in the manner described in Example 5 1: 1 mixture of phosphonosuccinic acid and α-methyl-phosphonosuccinic acid.

Example

Implementation of tetramethyl phosphonosuccinate with sodium methylate can also be carried out continuously. A 4.5-1 stainless steel reactor with heatable jacket and openings for stirrer, internal thermometer, addition of Methylate solution and tetramethyl phosphonosuccinate and derivation of reaction product and Methanol vapor is used. The heating mantle is supplied with oil from a thermostat with a circulation pump

6v. 280-310 ° C charged with two metering pumps Phosphonosuccinic acid tetramethyl ester (41.1 mol / h, corresponding to 10.46 kg / h) and methylate solution with a Content of 2.8 mol of sodium methylate / liter of methanol (20.5 mol / h-7.2 liters of solution / h) under intensive Stirring added. The evaporating methanol is condensed in a product cooler. The reaction temperature in the stainless steel reactor is 115-120 ° C. the reaction product, a mixture of phosphonobernary

stone methy'lester acid or its sodium salt, and oc-methyl-phosphonosuccinic acid-methylester and its sodium salt and a-methyl-phosphonosuccinic acid-methylester and its sodium salt is reheated in a 4-liter flask at 120 ⁰ C

The reaction mixture to be obtained is worked up in the manner described in Example 5 performed. It becomes a 1: 1 mixture of phosphono succinic acid and α-methylphosphonosuccinic acid.

Example 9

To 310 g (1 mol) of tetraethyl phosphonosuccinate is added dropwise at 150 ° C. with stirring The solution of 34 g (0.5 mol) of sodium ethylate in 185 ml of ethanol is heated within 2 hours. That Evaporating ethanol is distilled off. After the addition of ethylate is complete, the reaction mixture becomes 10 Stirred minutes

The reaction mixture is worked up in the manner described in Example 5. 375 g are obtained a 50% aqueous solution of a 1: 1 mixture of phosphonosuccinic acid and α-ethyl-phosphonosuccinic acid.

Example 10

To the solution of 1 mole of sodium-phosphonosuccinic acid tetramethylester in 200 ml of toluene, which was prepared as described in Example 1, is added dropwise with stirring at 30-40 ⁰ C, 126 g (1 mol) of benzyl chloride. The reaction mixture 4 hours at the indicated temperature stirred Then the reaction mixture with the solution of 1 mole of hydrogen chloride is added in 250 ml of dry ether The precipitated sodium chloride is filtered off and the Fiitrat by vacuum distillation up to a bottom temperature of 80 ⁰ C by all volatile compounds freed. The crude product consists essentially of methyl α-benzyl-phosphonosuccinate which is contaminated by methyl phosphonosuccinate and methyl α-methyl-phosphonosuccinate

The crude product is saponified in the manner described in Example 1

Example 11

To the suspension of 23 g (1 mol) of sodium in 300 ml of toluene with vigorous stirring and thorough cooling at 20-30 ⁰ C 422 g (1 mol) Phosphonobern- stone acid tetrabutyl ester eo. A clear solution of sodium phosphonosuccinic acid -te trabutyl ester in toluene is formed

Be at 88 * C 184 g (t TXST] ftafljöffid dropwise Then, with stirring over 1 hour to this solution, the Reaktkmsmischung is 2 hours at 80 ⁰ C is stirred then filtered off the precipitated sodium iodide and the Ffttrat by distillation in Valuimu to a Sufnpfttsnipentfnr of 100 ⁰ C of the volatile compounds beb ei t the residual crude product is gemfiB NMR spectrum of a 1: 9 mixture of butyl Phosphonobernstemsäure- and "butyl-phosphonosuccinic acid tert-butyl ester.

The mixture is saponified in the manner described in Example 1.

Example 12

To the solution of 1 mole of sodium-phosphono-tetraäthylester in 200 ml of toluene is added dropwise C. 154 g (1 mol) over 30 minutes at 60-70 ⁰

ίο diethyl sulfate The reaction mixture is stirred for 1 hour. The precipitated is filtered off Natriummonoäthylsulfat The Fiitrat is by distillation under vacuum up to a bottom temperature of 70 ⁰ C from toluene freed The resulting crude Λ-ethyl-phosphono-tetraäthylester is saponified in the manner described in Example 1,

Example 13

In a lemonade factory, bottles were made with a lye containing 2% caustic soda and an additive. Contains 0.1% of the following active ingredient concentrate, cleaned:

10% o-phosphoric acid,

10% a-methyl-phosphonosuccinic acid,
10% defoamer,
70% water.

The carbonate hardness of the water was 15 ° dH. The bottles were in perfect condition after being ejected cleaned and showed no limescale, and there were no limescale deposits on the cleaning machine.

14th

example

In a brewery the bottle was cleaned with a lye made from:

1.00% caustic soda,

0.03% orthophosphate

0.04% mixture of phosphonosuccinic acid and

Λ-methyl-phosphonosuccinic acid 1: 1,
0.02% defoamer.

The total hardness was 85 ° dH. The bottles were perfectly clean, free of limescale and well wetted. In contrast to the use of cleaning agents containing polyphosphate, no stone deposits were observed on the machine parts

Example 15

In a mineral water company, 10 ppm of a 1 : 1 mixture of * Pliospnonobenisteinsaure and «-Methyl

SS phosphono added The Verstemung the Nachspritzzone was so vöüig prevented, and the percentage of bottles by confinement of CO2 About tumbled, fell to zero, as in the bottles no lime crystals - the cause of the unwanted release of CO2 - had more deposited.

609530/477

Claims (5)

Patent Claims: 1. «-Substituted phosphonosuccinic acids of formula O R i! ! (HO) ₂ PC-COOH CH ₂ - COOH in which R stands for an alkyl radical with 1-4 carbon atoms or stands for the Aiiyi or Methailylrsst 2. Process for the preparation of substituted Phosphonosuccinic acids of the formula according to Claim 1, characterized in that tetraalkyl phosphonosuccinic acid esters are used the formula (R ₁ O) ₂ P-CH-COOR ₁
CH ₂ - COOR ₁ in which R ₁ denotes a lower alkyl radical, metalated, the metal atom is replaced by an aliphatic radical and then saponified under acidic conditions 3. The method according to claim 2, characterized in that the aliphatic radical with the help of dimethyl sulfate, diethyl sulfate. Introduces trimethyl phosphate or triethyl phosphate 4. The method according to claim 2, characterized in that the alkylating agent is phosphonosuccinic acid tetra-CiC ^ alkyl ester used. 5. Use of substituted phosphonosuccinic acid esters according to claim 1 as a sequestering agent. The invention relates to oc-substituted phosphonosuccinic acids the formula O R (HO) ₂ PC-COOH CH ₇ -COOH in which R stands for an alkyl radical with 1-4 carbon atoms or for the allyl or methallyl radical. The invention also relates to a process for the preparation of α-substituted phosphonic acids Formula I, which consists in using tetraalkyl phosphonosuccinic acid esters of the formula (R ₁ O) ₂ P-CH-COOR ₁
CH ₂ - COOR ₁ (11) in which Ri is a lower alkyl radical, metalated, the metal atom is replaced by an aliphatic radical and then saponified under acidic conditions, and the use of the compounds of formula 1 as sequestering agents