WO2021052768A1

WO2021052768A1 - Phosphonic acid derivatives and process for their preparation

Info

Publication number: WO2021052768A1
Application number: PCT/EP2020/074580
Authority: WO
Inventors: Carsten Rudolph; Thomas Kreher; Ulrich Stoeck; Stephan Liebsch
Original assignee: Zschimmer & Schwarz Mohsdorf GmbH & Co. KG
Priority date: 2019-09-17
Filing date: 2020-09-03
Publication date: 2021-03-25
Also published as: DE102019124958A1; DE102019124958B4

Abstract

The invention relates to phosphonic acid derivatives according to formula (I), a process for preparing them using 1,4 dicarboxylic acid derivatives and chloroalkylaminobis(alkylphosphonic acids) and their use as a functional additive.

Description

Phosphonic acid derivatives and processes for their preparation

The invention relates to phosphonic acid compounds according to formula (I), a process for their preparation using 1,4-dicarboxylic acid derivatives and chloroalkylaminobis (alkylphosphonic acids) and their use as a functional additive.

In a wide variety of industrial, institutional and domestic applications, water plays a crucial role as a medium. It takes on the function of the solvent for additives and as a reaction medium, acts as a transport medium or serves as a heat transfer medium. Examples in which these functions can be used include the use of detergents and cleaning agents, energy generation, the production of ceramic slips or the bleaching of natural fibers. Furthermore, the production of drinking water from service water by means of desalination processes such as reverse osmosis is of increasing importance.

These uses are usually associated with undesirable side effects of varying degrees, which can be traced back to the constituents of the water. Examples of this are: the deposition of poorly soluble compounds, in particular poorly soluble alkaline earth salts in water cycles or on membrane surfaces; the catalytic decomposition of bleach-active compounds such as hydrogen peroxide in the presence of heavy metal ions; as well as the re-soiling of textile fabrics due to the deposition of previously loosened dirt particles on the fibers during a washing process.

In order to circumvent these problems, substances have been developed over the past few decades which either minimize or completely eliminate one or even several of the above-mentioned problems. For example, water-soluble homo- and copolymers based on acrylic acid can be used to prevent the deposition of poorly soluble alkaline earth salts, with polymer properties being varied through the targeted selection of monomers and their stoichiometric ratios. Organic phosphonic acids with at least two phosphonic acid groups are also very suitable and often even more effective for avoiding deposits (so-called scale), which temporarily prevent precipitation and deposition even in an extremely low concentration range through special interactions with the substrate. Complex-forming compounds are used to mask heavy metal ions and avoid undesirable effects. The resulting metal complexes are very soluble in water and shield the metal ion from further chemical reactions. Examples of complex-forming compounds are polyaminopolycarboxylates or polyaminopolymethylene phosphonates, some of which have extremely high complex formation constants. The disadvantage of the cited classes of compounds is that they are considered to be not readily degradable according to the customary methods for determining the ready biodegradability.

Structures which, due to their chemical structure and (partial) charges, are able to adsorb on the surfaces of mineral particles can be used as dispersing aids. The transfer of negative charges to the mineral particles causes them to experience mutual repulsion and remain homogeneously distributed in a liquid phase without sedimenting. Common dispersants are homo- and copolymers of acrylic acid and organic phosphonic acids such as 1-hydroxyethane-1, 1-diphosphonic acid (HEDP), aminotris (methylenephosphonic acid) (ATMP) or diethylenetriaminepenta (methylenephosphonic acid) (DTPMP).

DE 2 233 273 A describes condensed polyalkylenepolyamine derivatives of the general formula

and their use for inhibiting the precipitation or the deposition of scale-forming salts from aqueous solutions. The radicals Ri, R2, R4 and R5 are preferably phosphonic acid radicals and / or radicals containing carboxyl groups.

DE 2 214 144 A discloses a process for the production of ethylenediamine-mono-β-propionic acid tri- (methylenephosphonic acid).

Other aminopolycarboxylic acids and their salts, such as the methylglycinediacetic acid (MGDA) disclosed in EP 0781762 A1 and the glutamine diacetic acid (GLDA) disclosed in WO 2009/024518 A1, are an alternative to the substance classes mentioned.

US 3,077,487 A discloses compounds of the formula

wherein the radicals Zi and Z2 are 1,4-conjugated polycarboxyl group-containing lower alkenyl groups with at least two carboxyl groups.

EP 0 772 084 A2 describes metal complexes of various polyamino monosuccinic acids for use as bleaching agents in photographic developer solutions.

Iminodisuccinic acid (IDS), for example disclosed in WO 201 ^ 179692 A1, EP 3 127 896 A1 and WO 9845251 A1, the aminosuccinic acid derivative 3-hydroxy-2,2'-iminodisuccinic acid (HIDS) described in DE 4024552 A1 and others in JPH 09157232 A disclosed aminopolycarboxylic acids as alternative complexing agents and corresponding processes for their preparation. An advantageous property of these substances is their easy biodegradability. However, their lower complex formation constants with heavy metals and the lack of a further functional property such as the ability to disperse particles are disadvantageous.

WO 9634126 A1 describes biodegradable chelating agents as complexing agents, in particular according to formula [1] or formula [2]

R ¹

C H- C OOM

/

R ^z -N

\ A ¹ - CH ^{- NH - A 5} - NH - CH - A ³

(C H.) "- A

R ^s A ^z - (C Hs) " ⁴

[1] [2] with radicals selected from -H, -OH, -COOH, -S0 ₃ , -P0 ₃ , -NH ₂ , -CONH ₂ , -NHC (= NH) NH ₂ , and

SH.

Organic aminomethylene phosphonic acids and their salts are usually prepared by the method of Moedritzer and Irani (Moedritzer and Irani, 1966). The aminomethylene phosphonates that can be prepared on the basis of primary and secondary amines are generally not considered to be readily biodegradable. EP 2 125 844 B1 and EP 2 716646 B1 disclose phosphonate derivatives by linking a reactive phosphonate with amino carboxylic acids or amino alcohols. The pH of the reaction mixture is between pH 8 and pH 14, the reaction temperature between 0 ° C and 200 ° C or 50 ° C and 140 ° C. Furthermore, EP 2 125 844 B1 discloses the use of the phosphonate compounds as dispersants, water treatment agents, deposit inhibitors, pharmaceuticals, pharmaceutical intermediates, surfactants, agents for secondary oil extraction, fertilizers or micronutrients. Statements on the biodegradability of the phosphonate compounds are not available.

The object of the present invention is therefore to provide biodegradable compounds with at least one functional property selected from complex formation, hardness stabilization (threshold activity), dispersibility, and corrosion inhibition.

A further object of the invention is to provide a method for their production. According to the invention, the object is achieved by a compound of the formula (I)

in which

R ^{1 is} selected from the group comprising -H, unsubstituted and substituted, unbranched and branched C1- to C25-alkyl and alkenyl radicals,

R ^{2 is} selected from the group comprising carboxyl and carboxyalkyl radicals,

R ³ and R ^{4 are} each independently selected from the group comprising —H, —CH ₃ and —OH, and n = 2 or 3, and salts thereof. The compounds according to the invention are advantageously biodegradable according to the standard test methods published in the Technical Guidelines of the OECD, in particular inherently degradable according to OECD 302 and thus environmentally friendly. In degradation tests for ready biodegradability according to OECD 301 A and OECD 301 F, the compounds according to the invention particularly advantageously have degradation rates which allow classification as readily biodegradable. Furthermore, these compounds advantageously have the property that the biological degradation processes also take place in situations where there is a lack of phosphorus and the phosphorus contained in the molecule can be released and metabolized in the process. The compounds according to the invention also advantageously have a high molar complexing capacity compared to conventional biodegradable complexing agents such as methylglycine diacetic acid (MGDA), N, N-bis (carboxylatomethyl) -L-glutamate (GLDA), iminodisuccinate (IDS) or hydroxyiminodisuccinic acid (HIDS). The compounds according to the invention are also advantageously not hazardous to health and have adequate stability. Furthermore, the compounds according to the invention are advantageously capable of interacting with sparingly soluble alkaline earth salts through the terminal phosphonic acid groups and are thus an encrustation inhibitor that is less than stoichiometrically effective. Furthermore, the compounds according to the invention show particularly good dispersing properties.

According to the invention, the term “alkenyl radical” is understood to mean an alkyl radical with at least one carbon-carbon double bond. The term “C1 to C25 alkyl and alkenyl radicals” is understood to mean alkyl and alkenyl radicals with 1 to 25 carbon (C) atoms.

In embodiments of the compounds ^{according to the invention, R 1 is selected} from the group comprising —H, unsubstituted and substituted, unbranched and branched C1 to C7 alkyl and alkenyl radicals.

In further embodiments of the compound ^{according to the invention, R 1 is} selected from substituted alkyl radicals, the alkyl radicals having at least one substituent selected from aryl, heteroaryl, amide, carboxyl, guanidino and / or hydroxyl group. In an embodiment with at least two substituents, the substituents can be the same or different.

The term “heteroaryl group” is understood to mean aromatics whose ring structure contains at least one heteroatom. The term “heteroatoms” is understood to mean atoms that are not carbon or hydrogen. Heteroatoms are preferably selected from the group comprising oxygen, nitrogen and sulfur. Is preferred

an amino acid residue, particularly preferably an α-amino acid residue. The term “amino acid residue” is understood to mean an organic compound comprising at least one amino group and at least one carboxyl group, the amino group being substituted.

In a preferred embodiment is

a proteinogenic amino acid residue. The term “proteinogenic” is understood to mean amino acids, which are building blocks of peptides or proteins and are encoded by codons in the DNA. Proteinogenic amino acids are selected from alanine, arginine, asparagine, aspartic acid, cysteine, glutamine, glutamic acid, glycine, histidine, isoleucine, leucine, lysine, methionine, phenylalanine, proline, serine, threonine, tryptophan, tyrosine and valine.

In further embodiments, R ^{1 is selected} from the group comprising -H, -CH ₃ and -phenyl.

In one embodiment of the compounds ^{according to the invention, R 2} = - (CH 2) COOH, where m = 0 to 11. Preferably m = 0 to 2, ie m = 0, 1 or 2.

In further embodiments, R ³ and R ^{4 are selected} from -H, -CH ₃ and -OH, preferably selected from -H and -H, -H and -CH ₃ or -H and -OH, that is to say R ³ = -H and R ⁴ = -H, R ³ = -H and R ⁴ = -CH ₃ , R ³ = -CH ₃ and R ⁴ = -H, R ³ = -H and R ⁴ = -OH or R ³ = -OH and R ⁴ = —H, particularly preferably selected from —H and —H or —H and —OH, that is, R ³ = —H and R ⁴ = —H, R ³ = —H and R ⁴ = —OH or R ³ = -OH and R ⁴ = -H.

Preferably R ³ = R ⁴ = -H.

According to the invention, n = 2 or 3. A short-chain alkyl group, in particular an ethylene group or a propylene group, advantageously occupies several coordination sites between the nitrogen atoms in the compounds according to the invention Metal atom or ion achieved by a molecule and thus an increase in the ability to complex.

In a preferred embodiment of the compounds according to the invention, n = 2.

According to the invention, the term “salts” is understood to mean the compounds according to the invention having at least one deprotonated carboxyl and / or phosphonic acid group and at least one positively charged counterion.

In further embodiments, the compounds according to the invention are alkali or ammonium salts, preferably sodium or potassium salts, that is to say a salt comprising alkali or ammonium cations, preferably sodium or potassium cations as counterions. In further embodiments, the compounds according to the invention have 0 to 8 deprotonated carboxyl and / or phosphonic acid groups and alkali or ammonium cations as counterions, preferably 2 to 7 deprotonated carboxyl and / or phosphonic acid groups and alkali or ammonium cations as counterions.

Particularly preferred embodiments of the compounds according to the invention are the following individual compounds:

N- (2- (bis (phosphonomethyl) amino) - N- (2- (bis (phosphonomethyl) amino) ethyl) -ethyl) -N- (1-carboxyethyl) aspartic acid, N- (1-carboxy-4-guanidinobutyl ) aspartic acid,

N- (3-Amino-1-carboxy-3-oxopropyl) -N- (2-bis- 2,2 '- ((2- (bis (phosphonomethyl) amino) -

(phosphonomethyl) amino) ethyl) aspartic acid, ethyl) azanediyl) disuccinic acid,

N- (2- (bis (phosphonomethyl) amino) ethyl) - N- (2- (bis (phosphonomethyl) amino) ethyl) -

N- (2-carboxyethyl) aspartic acid, N- (3-carboxypropyl) aspartic acid,

N- (4-Amino-1-carboxy-4-oxobutyl) -N- (2-bis- N- (2- (bis (phosphonomethyl) amino) ethyl) -

(phosphonomethyl) amino) ethyl) aspartic acid, N- (1,2-dicarboxyethyl) glutamic acid,

N- (2- (bis (phosphonomethyl) amino) ethyl) -

N- (carboxymethyl) aspartic acid,

N- (1-carboxy-3-methylbutyl) aspartic acid, N- (1-carboxy-2-phenylethyl) aspartic acid,

N- (2- (bis (phosphonomethyl) amino) ethyl) - N- (2- (bis (phosphonomethyl) amino) ethyl) -N-

N- (1-carboxy-2-hydroxyethyl) aspartic acid, (1-carboxy-2-hydroxypropyl) aspartic acid,

N- (2- (bis (phosphonomethyl) amino) ethyl) -N- (1- N- (2- (bis (phosphonomethyl) amino) ethyl) -N-carboxy-2- (4-hydroxyphenyl) ethyl) aspartic acid, (1-carboxy-2-methylpropyl) aspartic acid, ^'

N- (2- (bis (phosphonomethyl) amino) ethyl) -N- (5-carboxypentyl) aspartic acid,

2 - ((2- (bis (phosphonomethyl) amino) ethyl) (1- 2 - ((2- (bis (phosphonomethyl) amino) - carboxyethyl) amino) -3-hydroxysuccinic acid, ethyl) (1-carboxy-4- guanidinobutyl) -amino) -3- hydroxysuccinic acid,

2 - ((3-Amino-1-carboxy-3-oxopropyl) (2- (to 2 - ((2- (Bis (phosphonomethyl) amino) -

(phosphonomethyl) amino) ethyl) amino) -3- ethyl) (1,2-dicarboxyethyl) amino) -3- hydroxysuccinic acid, hydroxysuccinic acid,

2 - ((2- (bis (phosphonomethyl) amino) ethyl) (2- 2 - ((2- (bis (phosphonomethyl) amino) ethyl) (3-carboxy-ethyl) amino) -3-hydroxysuccinic acid, carboxypropyl) amino ) -3- hydroxysuccinic acid,

2 - ((4-Amino-1-carboxy-4-oxobutyl) (2- (bis- N- (2- (bis (phosphonomethyl) amino) ethyl) -

(phos-phonomethyl) amino) ethyl) amino) -3- N- (1,2-dicarboxy-2-hydroxyethyl) glutamine- hydroxysuccinic acid, acid,

2 - ((2- (bis (phosphonomethyl) amino) ethyl) (car- 2 - ((2- (bis (phosphonomethyl) amino) ethyl) (1-boxy (methyl) amino) -3-hydroxysuccinic acid, carboxy-2 -methylbutyl) amino) -3-hydroxysuccinic acid,

2 - ((2- (bis (phosphonomethyl) amino) ethyl) (1-carboxy- 2 - ((2- (bis (phosphonomethyl) amino) ethyl) 4-methylpentyl) amino) -3-hydroxysuccinic acid, - (1- carboxy-2-phenylethyl) amino) -3 hydroxysuccinic acid,

2 - ((2- (bis (phosphonomethyl) amino) ethyl) (1- 2 - ((2- (bis (phosphonomethyl) amino) ethyl) (1-carboxy-2-hydroxyethyl) amino) -3-hydroxy-carboxy -2-hydroxypropyl) amino) -3-hydroxysuccinic acid, succinic acid,

2 - ((2- (bis (phosphonomethyl) amino) ethyl) (1- 2 - ((2- (bis (phosphonomethyl) amino) ethyl) (1- carboxy-2- (4-hydroxyphenyl) ethyl) amino) - 3- carboxy-2-methylpropyl) amino) -3-hydroxy-hydroxysuccinic acid, succinic acid and their salts, preferably their sodium or potassium salts.

The invention also relates to a process for the preparation of a compound according to the invention comprising a) providing a 1,4-dicarboxylic acid derivative and adding alkali metal hydroxide, b) reaction of the 1,4-dicarboxylic acid derivative with ammonia or a primary amine to form an aspartic acid derivative, c) reaction of the Aspartic acid derivative with a chloroalkylaminobis (alkylphosphonic acid).

In one embodiment, the method takes place in the order of steps a), b) and c).

The term “1,4-dicarboxylic acid derivative” is understood to mean an organic compound with two terminal carboxyl groups and a reactive structural unit in the 2,3-position, the reactive structural unit being selected from a double bond and an epoxy group.

In embodiments of the method, the 1,4-dicarboxylic acid derivative is selected from maleic acid, maleic anhydride, citraconic acid and a 1,2-cis-epoxysuccinic acid.

The term "aspartic acid derivative" is understood to mean an organic compound with a secondary amino group and two terminal carboxyl groups in the 1,3-position, wherein the secondary amino group is derivatized by a group comprising -H, unsubstituted and substituted, unbranched and branched C1 to C25 alkyl and alkenyl radicals and a group comprising carboxyl and carboxyalkyl radicals.

The primary amine preferably has at least one carboxyl group. In one embodiment, the primary amine is an amino acid, preferably an α-amino acid.

In a further embodiment, the amino acid is an L-amino acid, a D-amino acid or a mixture of L- and D-amino acids, preferably an L-amino acid.

In one embodiment of the method, step a) taking place at a temperature in the range from 0 ° C. to 80 ° C., preferably in the range from 10 ° C. to 70 ° C., particularly preferably in the range from 40 ° C. to 60 ° C., step b) at a temperature in the range from 80 ° C. to 150 ° C., preferably in the range from 90 ° C. to 150 ° C., particularly preferably in the range from 100 ° C. to 150 ° C., and / or step c) at a temperature in the range from 0 ° C. to 40.degree. C., preferably in the range from 20.degree. C. to 30.degree. C., particularly preferably at room temperature.

In embodiments of the method, the alkali hydroxide is sodium hydroxide and / or potassium hydroxide.

In further embodiments, the chloroalkylaminobis (alkylphosphonic acid) is selected from 2-chloroethylaminobis (methylene phosphonic acid) and 3-chloropropylaminobis (methylene phosphonic acid).

In further embodiments, the reaction with a chloroalkylaminobis (alkylenephosphonic acid) takes place in step c) with the addition of alkali metal hydroxide, preferably sodium hydroxide and / or potassium hydroxide. The addition of alkali hydroxide advantageously increases the solubility of the chloroalkylaminobis (alkylphosphonic acid).

In one embodiment of step c), the chloroalkylaminobis (alkylphosphonic acid) is initially introduced into a solvent and the aspartic acid derivative is added, preferably continuously added dropwise as an aqueous solution. In a further embodiment of step c), the aspartic acid derivative is initially charged and the chloroalkylaminobis (alkylphosphonic acid) is added, preferably continuously added dropwise as an aqueous solution.

In a further embodiment of step c), alkali metal hydroxide is also added simultaneously and in parallel with the addition of the chloroalkylaminobis (alkylenephosphonic acid).

Another aspect of the invention relates to the use of at least one compound according to the invention as a functional additive, preferably a dispersant, complexing agent, corrosion inhibitor, hardness stabilizer.

The term “functional additive” is understood to mean an additive for modifying, in particular improving, the properties of a product, preferably for chemical products for use in water treatment, oil field chemistry, the detergent and cleaning agent industry or the pulp, paper and textile industry.

The term “dispersant” is understood to mean a substance which enables or stabilizes the optimal mixing of at least two non-homogeneously miscible substances, in particular suspensions.

The term “complexing agent” is understood to mean a substance which coordinates metal ions or metal atoms as Lewis acids, in particular for masking chemical properties of the metal ions or metal atoms. Complexing agents are advantageously used in washing or cleaning agents to mask the hardness of the water.

The term “corrosion inhibitor” is understood to mean a substance which temporarily or permanently protects materials against electrochemical attack. Corrosion inhibitors in a corrosive medium, in particular water, protect surfaces which are permanently in contact with the medium.

The term “hardness stabilizer” is understood to mean a substance which, in sub-stoichiometric amounts, prevents or delays the further formation and precipitation of the poorly soluble alkaline earth compounds through interactions with crystallites of poorly soluble alkaline earth compounds. In embodiments, the compounds according to the invention are used as readily biodegradable complexing agents.

In embodiments, the compounds according to the invention are used as a functional additive, in particular as a hardness stabilizer, in cooling water systems, desalination plants, preferably thermal desalination plants, and / or in oil production. In further embodiments, the compounds according to the invention are used as a functional additive, in particular as a hardness stabilizer, in oil or gas production, in washing and cleaning processes, in textile, pulp or paper manufacture and treatment, in galvanic processes and in agrochemical applications such as fertilizing with trace elements or avoiding intolerances caused by water hardness.

In embodiments, the compounds according to the invention are used as complexing agents for the paper and pulp industry, as bleach stabilizers for hydrogen peroxide bleaching (so-called P stage) and as complexing agents for removing troublesome metal ions in what is known as complexing agent washing (so-called Q stage). In further embodiments, the compounds according to the invention are used as a dispersing additive for fillers and for adjusting the viscosity of paper coating slips in paper manufacture.

Another aspect of the invention relates to the use of the compounds according to the invention for the production of detergents or cleaning agents, for the production of formulations, preferably for textile, pulp and paper production and treatment for the ceramics industry, for the oil and natural gas industry or for Water treatment. The use of the compounds according to the invention for the production of formulations for the electroplating industry and / or industrial agriculture is also included.

In embodiments, the compounds according to the invention are used in liquid or solid household detergents, in particular in household detergents in powder form or in granulated form.

In further embodiments, the compounds according to the invention are used in industrial and institutional cleaner formulations, for example in cleaners for hard surfaces (HSC), in bottle cleaners or workshop and tarpaulin cleaners. In further embodiments, the compounds according to the invention are used as a dispersant additive in ceramic formulations and applications.

A further aspect of the invention relates to the use of the compounds according to the invention for the production of agrochemical formulations, for example for stabilizing agrochemicals that are sensitive to water hardness in aqueous preparation or for providing dissolved transition metal ions as trace elements or nutrients, preferably in chelated form, so as to enable them to be absorbed into the plant organisms to facilitate.

In further embodiments, the compound according to the invention is used in formulations for electroplating processes, in particular by complexing dissolved metal ions in baths for electroplating.

To implement the invention, it is also expedient to combine the embodiments and features of the claims described above.

Embodiments

The invention is to be explained in more detail below with the aid of some exemplary embodiments and associated figures. The exemplary embodiments are intended to describe the invention without restricting it.

It show the

1 shows a diagram of the reaction A) an olefinic 1,4-dicarboxylic acid derivative with a primary amine to form an aspartic acid derivative and B) reaction of the aspartic acid derivative with a chloroalkylaminobis (alkylphosphonic acid).

2 shows a diagram of the reaction of an aspartic acid derivative, which is obtained by reacting a 1,4-dicarboxylic acid derivative with ammonia, with a chloroalkylaminobis (alkylphosphonic acid).

3 shows a diagram of the reaction of a 2,3-epoxy-1,4-dicarboxylic acid derivative with a primary amine to form an aspartic acid derivative.

4 shows a graphic representation of the prevention of deposits in the dynamic tube blocking test with the inhibitors IDS, DTPMP and IDS-EABMP.

Synthesis of iminodisuccinic acid (iminodisuccinic acid), tetrasodium salt (IDS-Na ₄ ):

A round-bottom flask equipped with a heater, stirrer, internal thermometer, reflux condenser and solids metering unit is charged with 43.8 g of water and mixed with 77.8 g of 50% strength Sodium hydroxide solution added. After homogenization has taken place, 19.8 g of maleic anhydride are added slowly and with good cooling so that the internal reactor temperature remains below 60.degree. 28.1 g of L-aspartic acid are then dissolved in the resulting solution and then heated to 100-110 ° C. for 44 h. To dissolve the solids that have formed, 10 g of water are added and then cooled. The main component of the solution is the tetrasodium salt of iminodisuccinic acid (90.2%) and the sodium salts of maleic acid (0.9%), fumaric acid (5.5%) and aspartic acid (3.4%).

The reaction mixture has a copper binding capacity of 74.8 mg Cu / g (corresponding to 1.18 mmol Cu / g). This value corresponds to a molar ratio n Cu: n IDS = 1: 1.

Synthesis of the tetrasodium salt of N- (1, 2-dicarboxyethyl) -L-glutamic acid (GIS-Na ₄ ):

60.0 g of water and 81.7 g (0.833 mol) of maleic anhydride are placed in a reaction vessel with a Teflon lining, which is equipped with external heating, stirrer, internal thermometer, reflux condenser and solids metering device. To this, the entire amount of 118.9 g of L-glutamic acid (0.808 mol) is added with stirring. 102.7 g (1.2835 mol) of 50% sodium hydroxide solution are now metered into this solution in portions, so that the internal reactor temperature does not rise above 85.degree. A further addition of 88.9 g (2.00 mol) of solid sodium hydroxide (90%) to the reaction mixture increases the temperature to 105-110 ° C. and reflux begins. The reaction mixture is kept at this temperature for 44 h. After adding 197 g of water, a clear, colorless solution with a dry matter of 49.1% and a density of 1.346 g / cm ^{3 is obtained} .

The main component of the solution is the tetrasodium salt of N- (1,2-dicarboxyethyl) -L-glutamic acid with a content of 92.6% determined ^{by 1 H-NMR spectroscopy.} Sodium maleate (0.4%), sodium fumarate (0.8%) and sodium malate (6.2%) are identified and quantified analogously as by-products.

Synthesis of the tetrapotassium salt of N- (1, 2-dicarboxyethyl) -L-glutamic acid (GIS-K ₄ ):

35.1 g of water and 97.1 g (0.778 mol) of 45% strength potassium hydroxide solution are placed in a round bottom flask equipped with a heater, stirrer, internal thermometer, reflux condenser and solids metering device. To this end, the entire amount (15.9 g = 0.162 mol) of maleic anhydride is added and dissolved over the course of 30 minutes with stirring, so that the temperature of the solution does not exceed 65.degree. 24.9 g (0.169 mol) of L-glutamic acid are then added in portions to this solution and also completely dissolved. The resulting mixture is then heated to reflux and at this temperature for 20 h left. The main component of the solution is the tetrapotassium salt of N- (1,2-dicarboxyethyl) -L-glutamic acid at 78%. Potassium maleate (0.7%), potassium fumarate (2.8%), potassium malate (18.5%) are ^{identified and quantified as by-products by means of 1} H-NMR spectroscopy.

Preparation of 2,2 '- ((2- (bis (phosphonomethyl) amino) ethyl) azandiyl) disuccinic acid, sodium salt (IDS-EABMP):

50 g (37.5 ml) of a solution of tetrasodium iminodisuccinate (Baypure CX 100/34) (1.18 mmol / g iminodisuccinic acid) are placed in a reaction vessel and the mixture is stirred at room temperature.

15.78 g (59 mmol) of crystalline 2-chloroethylaminobis (methylenephosphonic acid), 4.43 g (55.3 mmol) of 50% NaOH solution and 38 , 34 g of water produced a clear solution and transferred to a dropping funnel.

The solution from the dropping funnel is continuously added to the reaction vessel with tetrasodium iminodisuccinate solution over the course of 60 minutes while maintaining the internal temperature constant at 20 ° C. and stirring vigorously and then stirred for a further 60 minutes at room temperature to complete the chemical reaction.

108.5 g of a colorless aqueous solution are obtained, containing as the main component the sodium salt of 2,2 '- ((2- (bis (phosphonomethyl) amino) ethyl) azanediyl) disuccinic acid. The reaction mixture has a copper binding capacity of 64.0 mg Cu / g, corresponding to 1.008 mmol Cu / g. The theoretically possible amount of 2,2 '- ((2- (bis (phosphonomethyl) amino) ethyl) azandiyl) disuccinic acid is 0.543 mmol / g. This value corresponds to a molar ratio n Cu: n IDS-EABMP = 1.86: 1.

Product properties: pH (1% solution): 5.3 Dry matter: 38.1% Density: 1.249 g / cm ³

Copper binding capacity: 64.0 mg Cu / g product

IDS-EABMP: 24.2% calculated via complexometric titration with the molecular weight of the protonated form)

Calcium binding capacity: 1302 mg CaCCh / g (pH 9) active substance

Calcium binding capacity: 678 mg CaCCh / g (pH 11) active substance Preparation of 2 - ((2- (bis (phosphonomethyl) amino) ethyl) (1,2-dicarboxyethyl) amino) -3- hydroxysuccinic acid, sodium salt (HIDS-EABMP):

30 g of a solution of tetrasodium 3-hydroxyiminodisuccinate (Nippon Shokubai) (containing 1.6 mmol / g HIDS, determined by complexometric titration) are placed in a reaction vessel and stirred at room temperature.

12.84 g (48 mmol) of crystalline 2-chloroethylaminobis (methylenephosphonic acid), 3.6 g (45 mmol) of 50% NaOH solution and 38.34 g water prepared a clear solution and transferred to a dropping funnel.

In the reaction vessel with tetrasodium hydroxyiminodisuccinate solution, while keeping the internal temperature constant at 20 ° C and stirring vigorously, the solution from the dropping funnel is continuously added in full within 60 minutes and then stirred for a further 60 minutes at room temperature to complete the chemical reaction. 84.7 g of a colorless aqueous solution are obtained, containing as the main component the sodium salt of 2 - ((2- (bis (phosphonomethyl) amino) ethyl) (1,2-dicarboxyethyl) amino) -3-hydroxysuccinic acid.

The reaction mixture has a copper binding capacity of 71.8 mg Cu / g, corresponding to 1. 131 mmol Cu / g. The theoretically possible amount of 2 - ((2- (bis (phosphono-methyl) amino) ethyl) (1,2-dicarboxyethyl) amino) -3-hydroxysuccinic acid is 0.567 mmol / g. This value corresponds to a molar ratio n Cu: n IDS-EABMP = 1.99: 1.

Product properties: pH (1% solution): 5.1 dry matter: 39.2% density: 1.268 g / cm ³

Copper binding capacity: 71.8 mg Cu / g product

HIDS-EABMP: 28.0% (calculated using complexometric titration with the molecular weight of the protonated form)

Calcium binding capacity: 780 mg CaCCh / g (pH 9) active substance

Calcium binding capacity: 600 mg CaCCh / g (pH 11) active substance Preparation of pentasodium-2,2 '- ((2- (bis (phosphonomethyl) amino) ethyl) azandiyl) disuccinic acid:

50 g (37.5 ml) of a solution of tetrasodium iminodisuccinate (Baypure CX 100/34) (1.18 mmol / g iminodisuccinic acid) are placed in a reaction vessel and stirred at room temperature.

15.78 g (59 mmol) of crystalline 2-chloroethylaminobis (methylenephosphonic acid), 4.425 g (55.3 mmol) of 50% strength NaOH solution and 38, 34 g of water produced a clear solution.

In a receiving vessel B, a dilute aqueous NaOH solution is prepared from 4.72 (59 mmol) of 50% strength NaOH solution and 7.3 g of water.

In the reaction vessel with tetrasodium iminodisuccinate solution at a constant internal temperature of 20 ° C, the solution from receiving vessel A at 0.5 ml / min and the solution from receiving vessel B at 0.1 ml / min are simultaneously dosed via separate feeds the reaction mixture was stirred for 80 minutes.

120.5 g of a colorless aqueous solution are obtained containing 34.8 g of the pentasodium salt of 2,2 '- ((2- (bis (phosphonomethyl) amino) ethyl) azanediyl) disuccinic acid (28.9%) as the main component.

In an alternative embodiment, 50 ml (58.5 g) of an aqueous solution are prepared from 15.78 g (59 mmol) of 2-chloroethylaminobis (methylenephosphonic acid), 4.43 g (55.3 mmol) of 50% NaOH solution and 38.34 g of water placed in a reaction vessel and stirred at room temperature.

50 g of Baypure CX 100/34 (tetrasodium iminodisuccinate as an aqueous solution) are taken from a container A and 10 ml of a 19.6% NaOH solution (made from 4.72 g of 50% NaOH solution and 7.3 g of water) are added at a rate such that each solution is used up within 100 minutes. The reaction temperature is kept between 20.degree. And 30.degree. C. during this. After the addition is complete, the mixture is stirred for a further hour and 120.5 g of a colorless aqueous solution are obtained, containing 34.8 g of the pentasodium salt of 2,2 '- ((2- (bis (phosphonomethyl) amino) ethyl) as the main component azanediyl) disuccinic acid.

Product properties: pH (1% solution): 6.7 Dry matter: 35.7% Density: 1.242 g / cm ³ Copper binding capacity: 58.0 mg Cu / g product

IDS-EABMP: 21.9% (calculated using complexometric titration with the molecular weight of the protonated form)

Calcium binding capacity: 1300 mg CaCCh / g (pH 9) active substance

Calcium binding capacity: 670 mg CaCCh / g (pH 11) active substance

Preparation of the sodium salt of N- (2- (bis (phosphonomethyl) amino) ethyl) -N- (1,2-dicarboxyethvDglutamic acid (GIS-EABMP):

In a 500 ml round-bottomed flask equipped with a stirrer, internal thermometer and reflux condenser, 10.5 g of 50% sodium hydroxide solution are added to a suspension of 40.5 g of 2-chloroethylaminobis (methylenephosphonic acid) in 121.6 g of deionized water with external cooling and vigorous stirring. ig admitted. The internal reactor temperature remains at a maximum of 20 ° C. After stirring for 30 minutes, a homogeneous, almost colorless solution is obtained. This solution is then heated to 50 ° C. and 119.6 g of a solution of the sodium salt of N- (1,2-dicarboxyethyl) -L-glutamic acid as described above are added continuously over the course of one hour. The mixture is stirred for a further hour at this temperature and the aqueous solution is obtained with the following product properties: pH (1% solution): 5.1

Dry matter: 37.1%

Density: 1,238 g / cm ³

Copper binding capacity: 60.7 mg Cu / g product

GIS-EABMP: 23.6% (calculated using complexometric titration with the molecular weight of the protonated form)

Calcium binding capacity: 1570 mg CaCOs / g (pH 9) active substance

Calcium binding capacity: 670 mg CaCOs / g (pH 11) active substance

Production of the potassium salt of N- (2- (bis (phosphonomethyl) amino) ethyl) -N- (1,2-dicarboxyethvDglutamic acid (GIS-EABMP):

50 g of a solution of the potassium salt of 2 - ((1,2-dicarboxyethyl) amino) -4-hydroxypentanedioic acid, which was prepared as described above, are added at room temperature from a dropping funnel to a stirred solution of 3.3 g of 45% potassium hydroxide solution , 19.2 g of water and 7.5 g of 2-chloroethylaminobis (methylenephosphonic acid) were added over a period of 30 minutes. After the addition is complete, the mixture is stirred for a further 30 minutes. The Complexometric determination of the potassium salt of the resulting N- (2- (bis (phosphonomethyl) amino) ethyl) -N- (1,2-dicarboxyethyl) glutamic acid gives a copper binding capacity of 42.0 mg Cu / g product, which corresponds to a yield of 94, Corresponds to 2% of theory.

Production of the trisodium salt of (I-carboxyethyl) aspartic acid (Ala-IS, Na salt):

In a reaction vessel with a Teflon lining, 50 ml of deionized (VE) water are placed and 65.3 g (0.667 mol) of maleic anhydride are dissolved with stirring over the course of 30 minutes. 0.686 mol (61.1 g) of crystalline L-alanine are then added to this solution and the mixture is homogenized by stirring. A quantity of 1.212 mol of 50% strength NaOH solution (97.0 g) is then continuously added to the resulting slurry without additional cooling, the internal temperature rising to 90.degree. Finally, 0.808 mol of solid sodium hydroxide in prilled form is added and the mixture is heated to reflux, which begins at 105 ° C., with constant stirring. The reaction mixture is kept at this temperature for 27 hours and then cooled. 291.4 g of the reaction mixture are isolated, which are adjusted to a solids concentration of 49.6% by adding 86.6 g of deionized water.

According to determination by complexometric titration, the solution contains 139.3 g of the trisodium salt of (I-carboxyethyl) aspartic acid, corresponding to a yield of 91.8%.

Production of N- (2- (bis (phosphonomethyl) amino) ethyl) -N- (1-carboxyethyl) aspartic acid,

Sodium salt (Ala-IS-EABMP, Na salt):

A 250 ml round bottom flask equipped with a stirrer, internal thermometer, dropping funnel and reflux condenser is charged with 27.0 g of 2-chloroethylaminobis (methylenephosphonic acid) (purity 99%, 0.1 mol) and 81.1 g of deionized water and heated to 20 ° C. 0.0875 mol of NaOH in the form of a 50% solution (7.0 g) are then added to the slurry and the mixture is stirred until a clear solution is obtained. This mixture is heated to 60 ° C and then, within one hour, a mixture of 59.0 g of the aqueous solution of the trisodium salt of (1-

Carboxyethyl) aspartic acid (corresponding to 0.1 mol) and an identical amount of substance NaOH solution (50%) are metered into the solution of the chloroethylaminobis (methylenephosphonic acid). The reaction takes place for a further hour and then it is cooled.

181.8 g of a colorless, clear solution are obtained containing, as the main component, the sodium salt of N- (2- (bis (phosphonomethyl) amino) ethyl) -N- (1-carboxyethyl) aspartic acid. The reaction mixture has a copper binding capacity of 66.2 mg Cu / g, corresponding to 1.043 mmol Cu / g. The theoretically possible amount of N- (2- (Bis (phosphonomethyl) amino) ethyl) -N- (1-carboxyethyl) aspartic acid is 0.549 mmol / g. This value corresponds to a molar ratio n Cu: n Ala-IS-EABMP = 1.90: 1.

Product properties: pH (1% solution): 6.0

Dry matter: 34.7%

Density: 1,229 g / cm ³

Copper binding capacity: 66.2 mg Cu / g product

Ala-IS-EABMP: 22.7% (calculated using complexometric titration with the

Molecular weight of the protonated form)

Calcium binding capacity: 1550 mg CaCCh / g (pH 9) active substance

Calcium binding capacity: 660 mg CaCCh / g (pH 11) active substance.

Production of the trisodium salt of (2-carboxyethyl) aspartic acid (ß-Ala-IS, Na salt):

50 ml of deionized water are placed in a reaction vessel with a Teflon lining and the total amount of 65.3 g (0.667 mol) of maleic anhydride is dissolved with stirring within 30 minutes. Then 0.686 mol (61.1 g) of crystalline b-alanine are added to this solution and the mixture is homogenized by stirring. A quantity of 1. 212 mol of 50% strength NaOH solution (97.0 g) is then continuously added to the resulting slurry without additional cooling, the internal temperature rising to 90.degree. Finally, 0.808 mol of solid sodium hydroxide in prilled form is added and the mixture is heated to reflux, which begins at 105 ° C., with constant stirring. The reaction mixture is then kept at this temperature for 29 hours and then cooled. When 70 ° C. is reached, 74.2 g of deionized water are added and 371.1 g of a clear solution with a solids content of 49.4% are obtained. According to determination by complexometric titration, the solution contains 45.0% of the trisodium salt of (2-carboxyethyl) aspartic acid. This corresponds to a yield of 91.1%.

Production of N- (2- (bis (phosphonomethyl) amino) ethyl) -N- (2-carboxyethyl) aspartic acid,

Sodium salt (ß-Ala-IS-EABMP):

A 250 ml round bottom flask equipped with a stirrer, internal thermometer, dropping funnel and reflux condenser is charged with 27.0 g of 2-chloroethylaminobis (methylenephosphonic acid) (purity 99%, 0.1 mol) and 81.1 g of deionized water and heated to 20 ° C. 0.0875 mol of NaOH in the form of a 50% solution (7.0 g) are added to the slurry and the mixture is stirred until a clear solution is obtained. This mixture is heated to 40 ° C. and a mixture of 57.1 g of the aqueous solution of the trisodium salt of (2-carboxyethyl) aspartic acid (corresponding to 0.1 mol) is metered into the solution of chloroethylaminobis (methylenephosphonic acid) over the course of one hour. The reaction continues for an additional hour. The solution is then cooled. 172.2 g of a colorless, clear solution are obtained containing, as the main component, the sodium salt of N- (2- (bis (phosphonomethyl) amino) ethyl) - N- (2-carboxyethyl) aspartic acid.

The reaction mixture has a copper binding capacity of 69.5 mg Cu / g or 1.094 mmol Cu / g. The theoretically possible amount of N- (2- (bis (phosphonomethyl) amino) ethyl) -N- (1-carboxyethyl) aspartic acid is 0.581 mmol / g. This value corresponds to a molar ratio n Cu: n -Ala-IS-EABMP of 1.88: 1.

Product properties: pH (1% solution): 4.8 Dry matter: 35.2% Density: 1,229 g / cm ³

Copper binding capacity: 69.5 mg Cu / g product ß-Ala-IS-EABMP: 23.9% (calculated using complexometric titration with the molecular weight of the protonated form)

Calcium binding capacity: 1460 mg CaCO3 / g (pH 9) active substance

Calcium binding capacity: 565 mg CaCO3 / g (pH 11) active substance

Production of the trisodium salt of (5-carboxypentyl) aspartic acid (6-AHS-IS, Na salt):

50 ml of deionized water are placed in a reaction vessel with a Teflon lining and the total amount of 82.2 g (0.839 mol) of maleic anhydride is dissolved with stirring over the course of 30 minutes. 0.864 mol (113.4 g) of 6-aminohexanoic acid (6-AHS) are then added to this solution with stirring. A quantity of 1.525 mol of 50% NaOH (122.0 g) is then added to this mixture within 30 minutes via a dropping funnel and then 42.2 g of NaOH in flakes (content 96.4%) . This mixture is heated to 105-110 ° C. with constant stirring and kept at this temperature for 28 hours. For better handling, the viscous and opaque liquid is adjusted to a solids content of 40% by adding deionized water. The resulting aqueous solution is colorless and clear and contains 84.5% of the target compound as well as 10.2% malic acid, 3.6% fumaric acid and 0.4% maleic acid in the form of the completely neutralized sodium salts, regardless of the solvent. Production of N- (2- (bis (phosphonomethyl) amino) ethyl) -N- (5-carboxypentyl) aspartic acid,

Sodium salt (6-AHS-IS-EABMP. Na salt):

A 250 ml round bottom flask equipped with a stirrer, internal thermometer, dropping funnel and reflux condenser is charged with 27.0 g of 2-chloroethylaminobis (methylenephosphonic acid) (purity 99%, 0.1 mol) and 81.1 g of deionized water and heated to 20 ° C . 0.0875 mol of NaOH in the form of a 50% solution (7.0 g) are added to the slurry and the mixture is stirred until a clear solution is obtained. This mixture is heated to 60 ° C. and 94.9 g of a mixture of 86.9 g of the aqueous solution of the trisodium salt of (5-carboxypentyl) aspartic acid and 8.0 g of NaOH solution (50%) are metered in over the course of one hour. After the metering has ended, the reaction mixture is left at 60 ° C. for two hours to complete the reaction. 209.9 g of a colorless, clear solution are obtained containing, as the main component, the sodium salt of N- (2- (bis (phosphonomethyl) amino) ethyl) -N- (5-carboxypentyl) aspartic acid.

The reaction mixture has a copper binding capacity of 33.2 mg Cu / g, corresponding to 0.529 mmol Cu / g. In contrast, the trisodium salt of (5-carboxypentyl) aspartic acid has no copper binding capacity.

Product properties: pH (1% solution): 6.4 Dry matter: 32.9% Density: 1.202 g / cm ³

Copper binding capacity: 33.2 mg Cu / g product

6-AHS-IS-EABMP: 25.0% (calculated using complexometric titration with the molecular weight of the protonated form)

Calcium binding capacity: 1150 mg CaCCh / g (pH 9) active substance

Calcium binding capacity: 400 mg CaCCh / g (pH 11) active substance

Synthesis of the trisodium salt of (3-carboxypropyl) aspartic acid (GABA-IS, Na salt):

50 ml of deionized water are placed in a reaction vessel with a Teflon lining and the total amount of 65.3 g (0.666 mol) of maleic anhydride is dissolved with stirring over the course of 30 minutes. 0.686 mol (70.8 g) of y- (aminobutyric acid (GABA) are then added to this solution with stirring. A quantity of 1.21 mol of 50% NaOH (96.8 g) is then added to this mixture of 20 minutes via a dropping funnel and then 33.2 g (0.798 mol) of NaOH in flakes (content 96.4%) Continuous stirring, this mixture is heated to 105-110 ° C and kept at this temperature for 28 h. For better handling, the viscous and cloudy liquid is adjusted to a solids content of approx. 45% by adding deionized water. The resulting aqueous solution contains 87.7 mol% of the target compound and 8.6 mol% of malic acid, 3.3 mol% of fumaric acid and 0.4 mol% of maleic acid in the form ^{, according to evaluation by 1 H-NMR spectroscopy} of the completely neutralized sodium salts without taking the solvent into account.

Synthesis of the sodium salt of N- (2- (bis (phosphonomethyl) amino) ethyl) -N- (3- carboxypropy-aspartic acid (GABA-IS-EABMP):

A 250 ml round bottom flask equipped with a stirrer, internal thermometer, dropping funnel and reflux condenser is charged with 27.0 g of 2-chloroethylaminobis (methylenephosphonic acid) (purity 99%, 0.1 mol) and 81.1 g of deionized water and heated to 20 ° C . 0.0875 mol of NaOH in the form of a 50% solution (7.0 g) are then added to the slurry and the mixture is stirred until a clear solution is obtained. This mixture is heated to 60 ° C. and then 70.4 g of the above-described aqueous solution of the trisodium salt of (3-carboxypropyl) aspartic acid and 8.0 g of NaOH solution (50%) are metered into the reaction flask in parallel over one hour. After the metering has ended, the reaction mixture is stirred for a further hour at 60 ° C. to complete the reaction.

193.4 g of a colorless, clear solution are obtained containing, as the main component, the sodium salt of N- (2- (bis (phosphonomethyl) amino) ethyl) -N- (3-carboxypropyl) aspartic acid.

The reaction mixture has a copper binding capacity of 32.4 mg Cu / g, corresponding to 0.51 mmol Cu / g. In contrast to this, the trisodium salt of (5-carboxypentyl) aspartic acid has no measurable copper binding capacity.

Product properties: pH (1% solution): 6.3 Dry matter: 35.2% Density: 1,222 g / cm ³

Copper binding capacity: 32.4 mg Cu / g product

GABA-IS-EABMP: 22.8% (calculated using complexometric titration with the molecular weight of the protonated form)

Calcium binding capacity: 1220 mg CaCOs / g (pH 9) active substance

Calcium binding capacity: 430 mg CaCOs / g (pH 11) active substance Characterization of the compounds according to the invention:

Determination of the calcium binding capacity

The determination of the calcium binding capacity is based on the titration of a solution of a substance capable of complex formation or hardness stabilization with a calcium salt solution in the presence of carbonate ions at a defined pH value, which is kept constant during the titration by adding sodium hydroxide. The visible formation of calcium carbonate is prevented until the binding capacity is exhausted. The end point of the titration is therefore the first permanent appearance of turbidity in the titration solution. Substances that only have a complexing (chelating) effect show a ratio of 1: 1 for the stoichiometric ratio of n (calcium): n (complexing agent). Substances that also have a hardness-stabilizing or dispersing combination of effects have a ratio of at least or greater than 2: 1 for the above-mentioned ratio.

Table 1 shows the measured values of the calcium binding capacity of the compounds according to the invention with solutions adjusted to 25% dry matter in each case with 1 g weight of the solution for the titration at pH 11.

Tab. 1: Calcium binding capacity of the compounds according to the invention compared to reference compounds (IDS = iminodisuccinic acid, HIDS = hydroxyiminodisuccinic acid, MGDA = methylglycinediacetic acid, DTPMP = diethylenetriaminepenta (methylenephosphonic acid)).

The values for the substances according to the invention clearly show the superstoichiometric prevention of CaCCh precipitation in comparison with exclusive complexing agents.

Determination of the stabilization of alkaline hydrogen peroxide bleaching liquors To simulate the alkaline bleaching of, for example, cellulose or cotton using hydrogen peroxide, the decrease in the hydrogen peroxide content is determined at elevated temperatures in the presence of transition metals, which act as a decomposition catalyst, within a certain period of time the test, the stronger the complexing effect.

The stabilization of alkaline hydrogen peroxide bleach liquors is determined using synthetic water with 20 ° dH and pH 10 at a temperature of 75 ° C for 30 minutes with a concentration of manganese of 10 ppm and an amount of stabilizer of 0.5 g (in each case as Solution with 25% dry matter) (Tab. 2).

Tab. 2: Results of the stabilization of alkaline hydrogen peroxide bleach liquors by the compounds according to the invention in comparison with reference compounds after 30 min.

Kaolin dispersion

First, 1 liter of a 0.15% by weight solution of the product to be tested is prepared. It is produced by mixing the calculated amount of the product with 500 g of water, adjusting the pH of the resulting solution with NaOH solution (50%) to a pH of 11.5 and making up to 1000 g with water.

In a beaker, 1 g of kaolin is then sprinkled into the solution at room temperature while stirring at room temperature and stirred until a homogeneous solution is achieved. The suspension obtained is then transferred to an Imhoff cylinder. With increasing Time it comes to settling (sedimentation) of the kaolin particles at the bottom of the conical cylinder. The volume of this soil body is determined at the specified times (Tab. 3). At the same time, the appearance of each individual phase is noted at the observation times (clear, cloudy).

Tab. 3: Results of the kaolin dispersion: volume of the sediment after 5 to 120 min (HMDTMP = hexamethylene diamine (tetramethylene phosphonic acid), DTPMP = diethylene triamine penta (methylene phosphonic acid), PBTC = phosphonobutane tricarboxylic acid).

The calculation of the dispersibility (Tab. 4) is carried out according to the following equation:

Volume lower phase [mZ] * 100

¹⁰⁰ - Volume lower phase (blank) [ml \ ⁼ Dispergierßhi _g keitl%]

Tab. 4: Results of the kaolin dispersion: Dispersibility in% after 5 to 120 minutes (HMDTP = hexamethylene diamine (tetramethylene phosphonic acid), DTPMP = diethylene triamine penta (methylene phosphonic acid), PBTC = phosphonobutane tricarboxylic acid).

In comparison with conventional phosphonic acid-based dispersants, the substances according to the invention show a comparable dispersibility.

Dispersion tests with 2% kaolin slurry

For the dispersion tests, 0.5% solutions, based on the active content as acid, of the products investigated as dispersants are first prepared in water with 20 ° dH and the solutions are adjusted to pH either with caustic soda or acetic acid, depending on the resulting pH (original) discontinued from 7.

Exactly 100 ml of the above-described solution are then placed in a 100 ml measuring cylinder with a ground joint, and 2 g of kaolin, which has previously been weighed with an accuracy of 1 mg, are added. After closing the measuring cylinder and shaking it vigorously for one minute, the standing cylinder is placed on a flat surface and the behavior of the freshly prepared dispersion is monitored over a defined period of time. In most cases, there is a separation in three phases:

Phase A = sediment phase at the bottom of the measuring cylinder Phase B = stable dispersion as the middle phase

Phase C = clear phase (without visible particles) at the upper end of the measuring cylinder

Tab. 5: Results of the dispersing tests with 2% kaolin slurry.

From the proportion of phase B, the absence of a clear phase C and the significantly lower formation of a sediment A, it is clear that the products according to the invention thus have a superior ability to stably disperse even larger amounts of inorganic particles such as kaolin in the aqueous medium and even outperform typical phosphonates in their effectiveness.

Static bottle test

The static bottle test (closed bottle test) serves to illustrate the threshold activity for inhibiting the precipitation of poorly soluble alkaline earth salts. For this purpose, the calcium sulfate inhibition is determined at 75 ° C.

Preparation of solutions with the following concentrations:

Solution A (cation solution) NaCl 17.64 g / l

CaCl ₂ ^* 6 H ₂ 0 120.55 g / l

MgCl ₂ ^* 6 H ₂ 0 2.97 g / l

Solution B (anion solution) Na ₂ SC> 4 ^* 10 H ₂ 0 73.66 g / l

Solution C (inhibitor solution) 10% solution adjusted to pH 6 (calculated on the active substance)

40 ml of solution B, which is heated to 75 ° C., is placed in a 100 ml narrow-neck screw-top bottle and the respective amount of solution C (inhibitor solution) is added. After the two solutions have been homogenized, a further 40 ml of solution A (cation solution), which is heated to 75 ° C., are added, the bottles are tightly closed, homogenized and stored in a drying cabinet at 75 ° C. for 4 hours. The appearance of the bottles is then documented before and after a solid formed is shaken and the turbidity of the shaken solution is determined on a HACH DR 3800 as FAU (Formazin Absorption Unit). After settling again, 5 ml of the supernatant solution are filtered through a 0.45 μm syringe filter, diluted by a factor of 1: 10,000 and then analyzed for the content of dissolved calcium using ICP-OES (Tab. 6). Values without additions relate to the dispersion obtained after shaking, which is stable for at least 30 minutes and does not sediment. Tab. 6: Results of the turbidity measurement of the compounds according to the invention in comparison with reference compounds (MGDA = methylglycinediacetic acid, HIDS = hydroxy-iminodisuccinic acid, IDS = iminodisuccinic acid, HMDTMP = hexamethylenediamine (tetramethylene phosphonic acid), DTPMP = diethylenetriamine ) Solid can be shaken up, but sinks back to the bottom very quickly (less than 1 minute) (b) Solid cannot be shaken up, crystalline sediment).

The higher the numerical values, the greater the cloudiness due to finely divided solids in the liquid phase. The turbidity in turn correlates with the amount of finely divided solid in the liquid phase. At high inhibitor concentrations, the turbidity measurement also provides information about the calcium tolerance of the inhibitor. In this context, calcium tolerance is understood to mean the solubility of the resulting calcium salts of the compounds used as inhibitors under the system conditions. If crystallization occurs at the bottom of the vessel, this indicates an insufficient ability of the test substance to influence the crystallization process. The substances according to the invention prevent crystallization and show a reduced turbidity than the reference compounds. They therefore have an improved calcium tolerance compared to reference phosphonates.

Determination of the CaSCU inhibition

The calcium sulfate inhibition is assessed by determining the dissolved calcium in the clear, supernatant solution and calculating the inhibiting effect according to the following formula: 100 = inhibition [%],

where c Ca (A) = concentration of dissolved calcium without inhibitor (blank sample) c Ca (B) = maximum concentration of dissolved calcium c Ca (C) = concentration of dissolved calcium in the sample.

Tab. 7: Results of the calcium sulfate inhibition of the compounds according to the invention in comparison to reference compounds (MGDA = methylglycinediacetic acid, HIDS = hydroxyiminodisuccinic acid, IDS = iminodisuccinic acid, HMDTP = hexamethylenediamine (tetramethylene phosphonic acid), DTPMP = diethylenetriaminepenta (methylenephosphonic acid), PBMP = diethylenetriaminepenta (methylenephosphonic acid).

To model the dynamic behavior in the prevention of deposits, the so-called “Dynamic Tube Blocking Test” is also carried out. The measuring principle is based on the injection of a) a cation solution, b) an anion solution and c) an anion solution containing the inhibitor of the same composition as under b), which are mixed homogeneously shortly before entering a heated capillary and thus exceed the maximum solubility at least one ion pair leads. This leads to the precipitation of the poorly soluble salt pair in the capillary, which is deposited on the walls of the capillary and steadily reduces the cross-section here. The increase in pressure in the capillary resulting from this cross-sectional reduction is recorded and when a defined limit differential pressure is reached, the test is automatically terminated and the capillary is prepared again for a new test according to a defined cleaning regime.

This method is used to determine the minimum inhibitor concentration (MIC) that is necessary to prevent the deposition of sparingly soluble salts within a defined time interval and with a defined salt load.

A DSL 625 (DSL = Dynamic Scale Loop) apparatus from “PSL Systemtechnik GmbH” (Osterode am Harz) is used to carry out the tests. The following parameters were chosen:

System pressure: 3.2 bar

Temperature: 80 ° C

Capillary dimensions: length: 2.0 m

Inner diameter: 0.88 mm pH: 6.0

Step time: 10 minutes Termination criterion: Differential pressure Dr = 0.2 bar Flow rate: 15 ml / min combined (sum of cations, anions and anion-inhibited solution).

Tab. 8: The composition of the salt system resulting after mixing solutions a), b) and c).

The behavior of the substances iminodisuccinic acid (IDS), diethylenetriaminepenta (methylenephosphonic acid) (DTPMP) and 2,2 '- ((2- (bis (phosphonomethyl) amino) ethyl) azanediyl) disuccinic acid (IDS-EABMP ) compared and the minimum inhibitor concentration (MIC) determined (Fig. 4). On the basis of FIG. 4, the following MIC values thus result: IDS: 50 ppm, DTPMP: 40 ppm and IDS-EABMP: 20 ppm.

The compound IDS-EABMP according to the invention shows a significant increase in performance compared with the reference substances and makes it possible to reduce the minimum amount of inhibitor required by at least 50%.

Determination of the ready biodegradability according to standardized test procedures The determination of the ready biodegradability is carried out according to the standards OECD TG 301 A as well as 301 F. The information about the breakdown of dissolved organic carbon (DOC) (OECD 301 A) or the oxygen consumption (OECD 301 F) allow the following assessments (Tab. 9).

Tab. 9: Characterization of the compounds according to the invention with regard to their ready biodegradability (a ... without taking nitrification into account, b ... taking into account nitrification, IDS = iminodisuccinic acid, GIS = N- (1,2-dicarboxyethyl) -L- Glutamic acid).

Production of a concentrated liquid detergent, suitable for individual packaging

(so-called “liguid caps” or “pods”) in water-soluble film with the compounds according to the invention

Example 1:

Example 2:

The specified individual components are mixed one after the other with stirring at room temperature. A clear formulation which is stable for several months is obtained in each case.

Production of a weakly foaming, strongly alkaline cleaner

Production of a foaming, strongly alkaline cleaner with anti-corrosion

characteristics

The specified individual components are mixed one after the other with stirring at room temperature. A clear formulation which is stable for several months is obtained in each case. Production of a micronutrient concentrate (Cu) in chelated form

For an aqueous micronutrient concentrate containing 0.5% dissolved copper in chelate form, 100 ml of water are mixed with 25.4 g of 25% IDS-EABMP, sodium salt. Then 3.3 g of copper (II) sulfate pentahydrate are sprinkled into the stirred solution and then adjusted to a pH of 7.7 with 6.3 g of 45% strength potassium hydroxide solution. The resulting solution is bright blue and is adjusted to the final concentration with a further 35 g of water. This nutrient solution can be combined with conventional NPK nutrient solutions.

Production of a micronutrient concentrate (Mn) in chelated form

For an aqueous micronutrient concentrate containing 0.5% dissolved manganese in chelate form, 50 ml of water are mixed with 12.8 g of 25% IDS-EABMP, sodium salt. Thereafter, 1.1 g of manganese (II) sulfate monohydrate are sprinkled into the stirred solution, then adjusted to a pH of 7.7 with 2.8 g of 45% strength potassium hydroxide solution and by further addition of 4.8 g of water to the desired metal concentration set. The solution obtained is clear and colorless and can be combined with conventional NPK nutrient solutions.

Preparation of a multi-element micronutrient solution

To prepare a solution of several nutrient components and trace elements, 185 g of a 20% solution of IDS-EABMP in the form of its potassium salt, 16.6 g calcium chloride hexahydrate, 22.0 g potassium sulfate, 4.0 g magnesium chloride hexahydrate, 29.0 g Ammonium nitrate, 33 mg manganese (II) sulfate monohydrate, 12 mg zinc sulfate heptahydrate, 50 mg iron (II) sulfate heptahydrate, 2 mg copper (II) sulfate pentahydrate, 25 mg sodium molybdate dihydrate and 140 mg boric acid one after the other in 500 ml deionized water at room temperature and then the pH of the solution was adjusted to 7.7 with 22.7 g of 45% strength potassium hydroxide solution. The solution obtained is pale green in color, clear and without residues.

Non-patent literature cited

Moedritzer K, Irani RR (1966) The Direct Synthesis of a-Aminomethylphosphonic Acids. Mannich-Type Reactions with Orthophosphorous Acid. J. Org. Chem, 31, 1603-1607.

OECD Guideline for Testing of Chemicals 301, Adopted by the Council on 17th July 1992, Ready Biodegradability.

Claims

1. Compound according to formula (I)

in which

R ³ and R ^{4 are} each independently selected from the group comprising —H, —CH ₃ and —OH, and n = 2 or 3, and salts thereof.

2. A compound according to claim 1, characterized in that R ^{1 is} selected from substituted alkyl groups, substituted alkyl groups being alkyl groups with at least one aryl group, heteroaryl group, amide group, carboxyl group, guanidino group and / or hydroxyl group.

3. Compound according to claim 1 or 2, characterized in that R ^{1 is} an amino acid residue.

4. A compound according to any one of claims 1 to 3, characterized in that R ^{2 is} - (CH ₂ ) mCOOH, where m = 0 to 11.

5. A compound according to any one of claims 1 to 4, characterized in that R ³ and R ^{4 are} -H and -H, -H and -CH3 or -H and -OH.

6. A compound according to any one of claims 1 to 5, characterized in that n = 2.

7. A compound according to any one of claims 1 to 6, characterized in that the compound according to formula (I) is an alkali or ammonium salt, preferably a sodium or potassium salt.

8. A process for the preparation of a compound according to any one of claims 1 to 7 comprising a) providing a 1,4-dicarboxylic acid derivative and adding alkali metal hydroxide, b) reaction of the 1,4-dicarboxylic acid derivative with ammonia or a primary amine to form an aspartic acid derivative, c) Reaction of the aspartic acid derivative with a chloroalkylaminobis (alkylphosphonic acid).

9. The method according to claim 8, characterized in that the 1,4-dicarboxylic acid derivative is maleic acid, maleic anhydride, citraconic acid or a 1,2-cis-epoxysuccinic acid.

10. The method according to claim 8 or 9, characterized in that the primary amine is an amino acid, preferably an α-amino acid.

11. The method according to any one of claims 8 to 10, characterized in that the alkali hydroxide is sodium hydroxide and / or potassium hydroxide

12. The method according to any one of claims 8 to 11, characterized in that the chloroalkylaminobis (alkylphosphonic acid) is 2-chloroethylaminobis (methylenephosphonic acid) or 2-chloropropylaminobis (methylenephosphonic acid).

13. Use of at least one compound according to one of claims 1 to 7 as a functional additive, preferably a dispersant, complexing agent, corrosion inhibitor and / or hardness stabilizer.

14. Use according to claim 13, characterized in that the use as a functional additive in cooling water systems, thermal desalination systems, reverse osmosis systems, in oil or gas production, in washing and cleaning processes, in textile, pulp or paper production and treatment, takes place in galvanic processes and / or in agrochemical applications.

15. Use of at least one compound according to one of claims 1 to 7 for the production of detergents or cleaning agents, for the production of formulations, preferably for Textile, pulp and paper manufacture and treatment, for the ceramics industry, for the oil and gas industry, for water treatment, for the galvanic industry or industrial agriculture.