EP0287885A1 - Process for the preparation of serine-N,N-diacetic acid and its derivatives - Google Patents

Abstract

Serine-N,N-diacetic acid and derivatives thereof are prepared in various ways and used in particular as complexing agents, bleaching agent stabilizers and builders in detergents.

Description

The invention relates to processes for the preparation of serine-N, N-diacetic acid and derivatives, their use in particular as complexing agents and detergents and cleaning agents containing them and the intermediate product serine-N, N-diacetonitrile for the production of serine-N, N-diacetic acid and their salts.

Complexing agents for alkaline earth metal ions and metal ions, for example calcium, magnesium, iron, manganese and copper, are required for a wide variety of technical fields.

Areas of use and uses include, for example, detergents and cleaning agents, technical applications for industrial cleaners, in electroplating, in water treatment and in polymerizations, the photographic industry, the textile industry and the paper industry, and various applications in pharmaceuticals, cosmetics, and food and in plant nutrition.

Complexing agents which are familiar and recognized to the person skilled in the art, in particular for detergents, are, for example, nitrilotriacetic acid (NTA), ethylenediaminetetraacetic acid (EDTA), ethylenediaminetetramethylenephosphonic acid (EDTMP), propylenediamine tetraacetic acid (PDTA), hydroxypropylenediamine ethylenediamine acid, hydroxypropyl ethylenediamine dihydroxy acid, (HPDTA), hydroxymethyl ethylenediamine dihydroxy acid, Diethylenetriaminepentaacetic acid and, for example, diethanolglycine, ethanolglycine, citric acid, glucoheptonic acid or tartaric acid, as described, for example, under the keyword washing agent Ullmann's Encyclopedia of Industrial Chemistry, 4th edition, volume 24, pp. 63-160, in particular pp. 91-96, Verlag Chemie, Weinheim, 1983.

The effect of the known compounds, some of which are used on a large scale, is not always optimal in individual cases. For example, NTA works very well as a complexing agent and, in washing and cleaning agents, works quite well as a builder to improve the whitening effect and to prevent deposits that cause incrustations and graying on the fabric. However, the effect as a bleach stabilizer is only weak. EDTA also shows despite its good complexity compared to heavy metals, only a moderate effect as a bleach stabilizer in detergents and cleaning agents.

In some cases, biodegradability also leaves something to be desired. In the usual tests, EDTA proves to be insufficiently biodegradable, as do PDTA or HPDTA and corresponding aminomethylene phosphonates, which are also often undesirable because of their phosphorus content.

In a publication by L. Erdey et al. in Acta Chim. Hung., Tomus 21, pp. 327-332 (1959) describe the complexing properties of 2,3-dihydroxypropylamine-N, N-diacetic acid, serine-N, N-diacetic acid, made from D, L-serine and chloroacetic acid, and L-gutamic acid-N, N-diacetic acid with regard to the stability of the complexes formed with alkaline earth metal ions. For the complexes with alkaline earth metal ions formed with serine-N, N-diacetic acid, it is found that their stability is lower than expected, since it was believed that the stability values of nitrilotriacetic acid could be achieved.

The applicability of these compounds as auxiliary complexing agents was investigated by adding them to zinc, iron (III), copper and nickel solutions, each at a pH of 13.5, and to aluminum solutions at a pH of 7. Serine-N, N-diacetic acid is found to hold zinc and copper ions in solution at a molar ratio of metal ion: complexing agent of 1: 2, excess metal ions being excreted. As a summary result, it is found that the examined compounds can be used as standard solutions, i.e. for the analysis of alkaline earth solutions, can only be used with very limited possibilities and that they can possibly be considered as auxiliary complexing agents for heavy metal ions.

The lack of complex binding capacity resulting from these results cannot give the person skilled in the art any suggestion for producing serine-N, N-diacetic acid and its derivatives and using it as a complexing agent.

The object of the present invention is to provide new complexing agents for alkaline earth and heavy metal ions for a wide variety of technical fields, in particular for detergents, which, in addition to good complexing properties, are ecologically harmless, contain no phosphorus if possible and are readily biodegradable. Technically advantageous manufacturing processes are also to be developed for these new complexing agents.

It has been found that serine-N, N-diacetic acid in the form of the free acid or in particular the sodium, potassium, ammonium or organic amine salts is an excellent complexing agent for calcium, magnesium and iron, copper, nickel and manganese ions represent, while the acid derivatives, especially amides, esters and the nitriles are preferred intermediates for the preparation of the acid and its salts.

in der Y für den Rest -COOH, der gegebenenfalls in Form eines Alkalimetall-, Ammonium- oder substituierten Ammoniumsalzes vorliegt, oder für den Rest -CN steht und
X eine Hydroxylgruppe, wobei die dadurch vorliegende Carbonsäuregruppe gegebenenfalls in Form eines Alkalimetall-, Ammonium- oder substituierten Ammoniumsalzes vorliegt, oder einen Rest -NR³R⁴, in dem R³ und R⁴ gleich oder verschiedenen sind und für ein Wasserstoffatom oder einen Alkylrest mit 1 bis 4 C-Atomen stehen,
bedeutet, indem man 1 Mol Serin (3-Hydroxy-2-aminopropionsäure) ggfs. in Form eines Alkalisalzes oder des Säureamids, ggfs. am Amidstickstoffatom durch ein oder zwei Alkylreste mit 1 bis 4 C-Atomen substituiert, in Wasser, einem organischen Lösungsmittel oder ihren Mischungen mit 2,0 bis 2,6 Mol Formaldehyd und 2,0 bis 2,3 Mol flüssigen Blausäure bei Tempera­turen von 0 bis 45°C oder mit 2,0 bis 2,3 Mol Alkalicyanid bei Tempera­turen von 40 bis 100°C umsetzt und ggfs. vorliegende Amid- und die Nitril­gruppen in Gegenwart von einer Säure oder Base hydrolysiert und ggfs. die freie Säure oder ein Salz gemäß Formel I isoliert.The invention therefore relates to a process for the preparation of compounds of the formula I.

in which Y represents the radical -COOH, which is optionally in the form of an alkali metal, ammonium or substituted ammonium salt, or represents the radical -CN and
X is a hydroxyl group, the carboxylic acid group thereby present optionally being in the form of an alkali metal, ammonium or substituted ammonium salt, or a radical -NR³R⁴, in which R³ and R⁴ are identical or different and represent a hydrogen atom or an alkyl radical with 1 to 4 C. -Atoms stand,
means by 1 mol of serine (3-hydroxy-2-aminopropionic acid), optionally in the form of an alkali salt or acid amide, optionally substituted on the amide nitrogen atom by one or two alkyl radicals having 1 to 4 carbon atoms, in water, an organic solvent or their mixtures with 2.0 to 2.6 mol of formaldehyde and 2.0 to 2.3 mol of liquid hydrocyanic acid at temperatures from 0 to 45 ° C. or with 2.0 to 2.3 mol of alkali metal cyanide at temperatures from 40 to 100 ° C and, if appropriate, hydrolyze the amide and nitrile groups present in the presence of an acid or base and, if appropriate, isolate the free acid or a salt of the formula I.

The free serine N, N-diacetic acid and the sodium, potassium and ammonium salts, in particular the trisodium, tripotassium and triammonium salt, and organic triamine salts with a tertiary nitrogen atom are to be mentioned in particular.

The bases on which the organic amine salts are based are, in particular, tertiary amines, such as trialkylamines having 1 to 4 carbon atoms in the alkyl, such as trimethyl and triethylamine, and trialkanolamines having 2 or 3 carbon atoms in the alkanol radical, preferably triethanolamine and tripropanolamine.

The preferred starting compound is serine in the form of its racemic mixture and optionally in the form of the sodium, potassium or ammonium salt.

The implementation takes place in a conventional manner in the manner of a Strecker synthesis, cf. Houben-Weyl, Vol. 11/2, pp. 408-412 (1958), Thieme-Verlag, Stuttgart.

Water is preferably used as the solvent, or organic solvents which are miscible with water, such as methanol, ethanol, n-propanol, isopropanol, tertiary butanol, dioxane or tetrahydrofuran. Mixtures of these organic solvents with one another or their mixtures with water can also be used. In the case of aqueous mixtures, 10 to 70% by weight of organic solvent is expediently added to the weight of the water.

The concentration of the starting compounds in the respective solvent is advantageously 10 to 80% by weight, preferably 20 to 70% by weight.

In a convenient and preferred reaction procedure, the sodium or potassium salt of the serine is in one of the above. Solvents or solvent mixtures, with an aqueous solution being preferred, are reacted with the formaldehyde in the form of its aqueous, about 30% by weight solution and the liquid hydrocyanic acid at the preferred temperatures of 15 to 25 ° C.

The reaction with akalicyanide, in particular sodium or potassium cyanide, is preferably carried out at 70 to 100 ° C. instead of the liquid hydrocyanic acid.

For the reaction with liquid hydrocyanic acid, pH ranges from 0 to 11, preferably 3 to 9, are expedient, which can be adjusted accordingly with an acid or base.

The resulting intermediate, serine-N, N-diacetonitrile, has not yet been described in the literature.

As a rule, for the nitrile groups present and any ester or amide groups present, hydrolysis or saponification to give the carboxylic acid is carried out in a conventional manner in an aqueous reaction mixture, if appropriate after adding water in the presence of alkalis, such as sodium or potassium hydroxide, or of acid such as sulfuric or hydrochloric acid.

This hydrolysis is expediently carried out at temperatures from 20 to 110 ° C., preferably 40 to 100 ° C., with a slight excess of base or acid, if necessary.

According to the reaction conditions, the serine-N, N-diacetic acid or an alkali salt is preferably obtained. Then salts with another cation can be prepared without further notice.

If necessary, an acid derivative can also be produced in the usual way from the acid obtained.

The compounds of formula I can be isolated in pure form without difficulty. Spray or freeze drying, crystallization or precipitation are particularly suitable for the free acid and the salts. It can be advantageous to use the resulting solution directly for technical use.

Furthermore, the compounds of the formula I, where the radical —COX additionally denotes a nitrile group, serine-N, N-diacetic acid and its salts, can be prepared
by glycolaldehyde with a compound of formula II
HN (CH₂-Y) ₂> II
in which Y has the meanings given for formula I and can additionally represent a radical -COOR¹, in which R¹ is an alkyl radical having 1 to 4 carbon atoms, with liquid hydrocyanic acid or an alkali metal cyanide in water, an organic solvent or their mixtures bie at temperatures of 10 to 100 ° C and optionally hydrolyzed the nitrile groups and amide or ester groups present in the presence of an acid or base and optionally isolated the free acid or a salt according to formula I.

The serine-N, N-diacetic acid and its salts are preferably prepared by this process.

The starting compounds of formula II are known or can easily be prepared by known processes. The starting compounds of the formula II are preferably the iminodiacetic acid, if appropriate in the form of the mono- or disodium, potassium or ammonium salt, the iminodiacetonitrile, the methyl and ethyl iminodiacetic acid.

In general, the same reaction conditions and molar ratios apply as in the process described above, in which formaldehyde is also used as the starting compound.

A compound of formula II, the glycol aldehyde, liquid hydrocyanic acid, sodium or potassium cyanide are preferably reacted in a molar ratio of 1: 1: 1.

The reaction is expediently carried out in such a way that a compound of the formula I with a nitrile group for the radical -COX as an intermediate is prepared from glycolaldehyde, liquid hydrocyanic acid and a compound of the formula II, preferably in aqueous solution, that subsequently in the manner indicated above is hydrolyzed or saponified.

However, it is possible to carry out the reaction of glycol aldehyde with an alkali metal cyanide and a compound of the formula II, preferably in aqueous solution, in such a way that the nitrile group is saponified during the reaction.

Otherwise, the above Solvents and solvent mixtures are used.

For the reactions with the glycol aldehyde, a pH range from 0 to 13, preferably 0.5 to 9, and temperatures from 10 to 100 ° C., preferably 10 to 60 ° C., are advantageous.

The hydrolysis of the nitrile group and any amide or ester groups present is expediently carried out as described above, temperatures from 20 to 110 ° C., preferably 40 to 100 ° C., with a slight excess of base or acid.

According to a third production process, the compounds of the formula I with the meaning nitrile for the radicals Y and -COX, the serine-N, N-diacetic acid and their salts are prepared by preparing nitrilotriacetonitrile with formaldehyde with base catalysis in a pH range from 7.5 to 12 at temperatures of 0 to 100 ° C, optionally hydrolyzed the nitrile groups in the presence of an acid or base and optionally isolated the free acid or a salt of formula I.

This process is a conventional base-catalyzed aldol addition of formaldehyde to a CH-acidic compound.

Formaldehyde, preferably in the form of the aqueous solution of about 30% by weight, and nitrilotriacetonitrile are in a molar ratio of 1: 1 to 5: 1, preferably 1: 1 to 3: 1, in a monohydric alcohol with 1 up to 4 carbon atoms, tetrahydrofuran, dioxane or water or one of their mixtures as solvent. In addition to water, the preferred solvents are a lower alcohol, such as methanol, ethanol or propanol.

Useful bases as catalysts are tertiary aliphatic amines, in particular trialkylamines and trialkanolamines, such as triethylamine or triethanolamine, alkaline earth metal hydroxides, in particular calcium and magnesium hydroxide, alkali metal hydroxides, such as sodium and potassium hydroxide, alkali metal carbonates, such as sodium and potassium carbonate, and also strongly basic synthetic resin anions made from synthetic anions the OH form.

In the presence of catalytic amounts of base, the reaction is carried out in a pH range from 7.5 to 12, preferably from 8.5 to 11, at temperatures from 0 to 100 ° C. and preferably 25 to 80 ° C.

The subsequent hydrolysis of the nitrile groups and the preparation and isolation of the salts is carried out as described above.

The production processes according to the invention have the advantage over known processes, in particular for the production of serine-N, N-diacetic acid and their salts, that there is practically no inorganic salt load. Due to the easy availability of the starting compounds, extremely inexpensive large-scale processes are made available.

The serine-N, N-diacetic acid and its salts produced by the invention are outstandingly suitable for complexing alkaline earth and heavy metal ions, in particular calcium, magnesium and iron, copper, nickel and manganese ions. Because of this ability, they have a variety of technical applications. Since they are biodegradable compounds, they can be used in large quantities wherever the waste water has to be clarified and phosphorus-containing compounds should also be avoided.

The complexing agents according to the invention can be used in washing and cleaning agents in order to control the content of free heavy metal ions in the washing agents themselves and in the washing solutions. The amount used as a complexing agent is advantageously 0.1 to 2% based on the total weight of the detergent components.

Their beneficial effect also lies in bleach stabilization, for example for sodium perborate, in detergents and in bleaching of textiles, cellulose or paper raw materials. Traces of heavy metals such as iron, copper and manganese occur in the washing powder itself, in the water and in the textile goods and catalyze the decomposition of the sodium perborate. The complexing agents according to the invention bind these metal ions and prevent the undesired decomposition of the bleaching system during storage and in the wash liquor. This increases the efficiency of the bleaching system and fiber damage is suppressed.

In addition, enzymes, opt. Brighteners and fragrances protected from heavy metal catalyzed oxidative decomposition.

In liquid detergent formulations, the new complexing agents can be used as so-called preservatives, advantageously in an amount of 0.05 to 1% by weight, based on the total weight of the detergent formulation.

In soaps, for example, the new complexing agents prevent metal-catalyzed oxidative decomposition.

Furthermore, they serve as an excellent builder in detergents and cleaning agents to prevent precipitation and incrustation on the fabric.

They can advantageously be used wherever the precipitation of Ca, Mg and heavy metal salts is to be disrupted and prevented in technical processes. For example, to prevent deposits and incrustations in boilers, pipelines, on spray nozzles or generally on smooth surfaces.

They can be used to stabilize phosphates in alkaline degreasing baths and prevent the precipitation of lime soaps, thereby preventing "tarnishing" of non-ferrous surfaces and extending the service life of alkaline cleaning baths.

They can be used as complexing agents in alkaline rust removal and descaling baths as well as in galvanic baths instead of cyanides to mask impurities.

The cooling water treatment with the new complex images prevents deposits or dissolves existing ones. Use in an alkaline medium and thus the elimination of corrosion problems is an advantage.

When polymerizing rubber, they can be used to produce the redox catalysts used. They also prevent the precipitation of iron hydroxide in the alkaline polymerization environment.

In the photographic industry, the new complexing agents can be used in developer / fixer baths made with hard water to prevent the precipitation of poorly soluble Ca and Mg salts. The precipitations lead to gray haze on films and images, as well as deposits in the tanks, which can thus advantageously be avoided. Iron III complexing agent solutions can advantageously be used in bleach-fix baths, where they can replace the hexacyanoferrate solutions, which are of ecological concern.

In the textile industry, they can be used to remove traces of heavy metals during the manufacturing or dyeing process of natural and synthetic fibers. This prevents many faults: dirt stains and streaks on the textile, loss of gloss, poor wettability, uneven dyeing and color errors.

In the paper industry they can be used to eliminate heavy metal / iron ions. The deposition of iron on paper leads to "hot spots" where the oxidative, catalytic destruction of cellulose begins.

Various applications include, for example, applications in pharmaceuticals, cosmetics and foodstuffs in order to prevent the metal-catalyzed oxidation of olefinic double bonds and thus the rancidity of the products.

In plant nutrition, Cu, Fe, Mn, Zn complexes are used to remedy heavy metal deficits. The heavy metals are added as chelates to prevent precipitation as biologically inactive, insoluble salts.

Other areas of application for the new complexing agents are flue gas scrubbing, namely the removal of NO _x from flue gases, H₂S oxidation, metal extraction, and use as catalysts for org. Syntheses (e.g. air oxidation of paraffins, hydroformylation of olefins to alcohols).

The complexing agents according to the invention for alkaline earth and heavy metal ions are used as complexing agents in general and very particularly in washing and cleaning agents and dishwashing and washing aids, in particular as complexing agents for heavy metal and / or alkaline earth metal ions, as bleach stabilizers and as builders.

The invention accordingly also relates to the corresponding uses and detergents and cleaning agents which contain these compounds in addition to the customary constituents known to the person skilled in the art.

The compounds to be used according to the invention are generally used in washing and cleaning formulations in an amount of 0.01 to 20% by weight, preferably 0.05 to 10% by weight, based on the total weight of the detergent formulation.

When used preferably as a builder, amounts from 1 to 10% by weight are preferred, when used as a bleach stabilizer for perborates, amounts from 0.05 to 1% by weight are particularly preferred. When used in particular as a complexing agent in detergents, amounts of 0.1 to 2% by weight are preferred.

Detergent and cleaning agent formulations which, based on the total weight, contain 0.01 to 20, preferably 0.05 to 10% by weight, of compound to be used according to the invention generally contain 6 to 25 as additional constituents, based on the total weight % By weight of surfactants, 15 to 50% by weight of builder and optionally co-builder, 5 to 35% by weight of bleach and optionally bleach activators, 3 to 30% by weight of auxiliaries such as enzymes, foam regulators, corrosion inhibitors, optical brighteners, fragrances, dyes , or formulation aids, such as Sodium sulfate.

The compounds according to the invention, in their capacity as complexing agents, builders and bleach stabilizers, can also be used in washing and cleaning formulations together with other agents of the prior art, the general properties with regard to sequestering, incrustation inhibition, primary washing action and bleaching action being able to be significantly improved under certain circumstances .

Typical constituents of detergent formulations known to the person skilled in the art, based on the framework regulation mentioned above, are listed below, for example:
Suitable surfactants are those which contain at least one hydrophobic organic radical and one water-solubilizing anionic, zwitterionic or nonionic group in the molecule. The hydrophobic radical is usually an aliphatic hydrocarbon radical with 8 to 26, preferably 10 to 22 and in particular 12 to 18 carbon atoms, or an alkyl aromatic radical with 6 to 18, preferably 8 to 16, aliphatic carbon atoms.

Suitable synthetic anionic surfactants are in particular those of the sulfonate, sulfate or synthetic carboxylate type.

The surfactants of the sulfonate type are alkylbenzenesulfonates with 4 to 15 carbon atoms in alkyl, mixtures of alkene and hydroxyalkanesulfonates and disulfonates, such as are obtained, for example, from monoolefins with terminal or internal double bonds by sulfonation with gaseous sulfur trioxide and subsequent alkaline or acidic hydrolysis of the sulfonation products receives. Also suitable are alkanesulfonates which can be obtained from alkanes by sulfochlorination or sulfoxidation and subsequent hydrolysis or neutralization or by bisulfite addition to olefins. Other useful sulfonate type surfactants are the esters of α-sulfo fatty acids, e.g. the α-sulfonic acids from hydrogenated methyl or ethyl esters of coconut, palm kernel or tallow fatty acid.

Suitable sulfate type surfactants are the sulfuric acid monoesters of primary alcohols, e.g. from coconut fatty alcohols, tallow fatty alcohols or oleyl alcohol, and those from secondary alcohols. Sulfated fatty acid alkanolamines, fatty acid monoglycerides or reaction products of 1 to 4 moles of ethylene oxide with primary or secondary fatty alcohols or alkylphenols are also suitable.

Other suitable anionic surfactants are the fatty acid esters or amides of hydroxy or aminocarboxylic acids or sulfonic acids, e.g. the fatty acid sarcosides, glycolates, lactates, taurides or isothionates.

The anionic surfactants can be in the form of their sodium, potassium and ammonium salts and also as soluble salts of organic bases, such as mono-, di- or triethanolamine. The usual soaps, i.e. Salts of natural fatty acids should not go unmentioned.

Examples of nonionic surfactants (nonionics) are adducts of 3 to 40, preferably 4 to 20, moles of ethylene oxide with 1 mole of fatty alcohol, alkylphenol, fatty acid, fatty amine, fatty acid amide or alkanesulfonamide usable. The addition products of 5 to 16 moles of ethylene oxide with coconut oil or tallow fatty alcohols, with oleyl alcohol or with synthetic alcohols with 8 to 18, preferably 12 to 18 carbon atoms, and with mono- or dialkylphenols with 6 to 14 carbon atoms in are particularly important the alkyl residues. In addition to these water-soluble nonionics, non-fully or not fully water-soluble polyglycol ethers with 1 to 4 ethylene glycol ether residues in the molecule are also of interest, in particular if they are used together with water-soluble nonionic or anionic surfactants.

Furthermore, the non-ionic surfactants which can be used are the water-soluble adducts of ethylene oxide with 20 to 250 ethylene glycol ether groups and 10 to 100 propylene glycol ether groups with polypropylene glycol ether, alkylene diaminopolypropylene glycol and alkyl polypropylene glycols with 1 to 10 C atoms in the alkyl chain, in which the polypropylene glycol ether chain acts as a hydrophobic residue.

Nonionic surfactants of the amine oxide or sulfoxide type can also be used.

The foaming power of the surfactants can be increased or decreased by combining suitable types of surfactants. A reduction can also be achieved by adding non-surfactant-like organic substances.

Suitable builder substances are, for example: washing alkalis, such as sodium carbonate and sodium silicate, or complexing agents, such as phosphates, or ion exchangers, such as zeolites, and mixtures thereof. These builders and builders have the task of eliminating the hardness ions, which come partly from water, partly from dirt or the textile material, and to support the surfactant effect. In addition to the above Builder substances can also be contained in the builder, so-called co-builders. In modern detergents, the co-builders have the task of adopting some properties of the phosphates, e.g. Sequestering effect, dirt-carrying capacity, primary and secondary washing effect.

For example, water-insoluble silicates, as described for example in DE-OS 24 12 837, and / or phosphates may be present in the builder. Pyrophosphate, triphosphate, higher polyphosphates and metaphosphates can be used from the group of phosphates. Organic complexing agents containing phosphorus, such as alkane polyphosphonic acids, amino and hydroxyalkane polyphosphonic acids and phosphonocarboxylic acids, also come as further detergent ingredients into consideration. Examples of such detergent additives are, for example, the following compounds: methane diphosphonic acid, propane-1,2,3-triphosphonic acid, butane-1,2,3,4-tetraphosphonic acid, polyvinylphosphonic acid, 1-aminoethane-1,1-diphosphonic acid, 1-amino-1 -phenyl-1,1-diphosphonic acid, aminotrismethylene triphosphonic acid, methylamino or ethylaminobismethylene diphosphonic acid, ethylenediaminotetramethylene tetraphosphonic acid, diethylene triaminopentamethylene pentaphosphonic acid, 1-hydroxyethane-1,1-diphosphonic acid, phosphonoacetic and phosphonopropionic acid, and / or polyphosphonate acid, and / or their polymer malpolymer partially or fully neutralized salts.

Other organic compounds which act as complexing agents for calcium and can be present in detergent formulations are polycarboxylic acids, hydroxycarboxylic acids and aminocarboxylic acids, which are mostly used in the form of their water-soluble salts.

Examples of polycarboxylic acids are dicarboxylic acids of the general formula HOOC- (CH₂) _m -COOH with m = 0-8, also maleic acid, methylene malonic acid, citraconic acid, mesaconic acid, itaconic acid, non-cyclic polycarboxylic acids with at least 3 carboxyl groups in the molecule, such as tricarballylic acid, aconitic acid, Ethylene tetracarboxylic acid, 1,1,3-propane-tetracarboxylic acid, 1,1,3,3,5,5-pentane-hexacarboxylic acid. Hexane hexacarboxylic acid, cyclic di- or polycarboxylic acids, such as, for example, cyclopentane tetracarboxylic acid, cyclohexane hexacarboxylic acid, tetrahydrofuran tetracarboxylic acid, phthalic acid, terephthalic acid, benzene tri-, tetra- or pentacarboxylic acid and mellitic acid.

Examples of hydroxymono- or polycarboxylic acids are glycolic acid, lactic acid, malic acid, tartronic acid, methyltartronic acid, gluconic acid, glyceric acid, citric acid, tartaric acid, salicylic acid.

Examples of aminocarboxylic acids are glycine, glyclglycine, alanine, asparagine, glutamic acid, aminobenzoic acid, iminodi- or triacetic acid, hydroxyethyliminodiacetic acid, ethylenediaminotetraacetic acid, hydroxyethyl-ethylenediamine-triacetic acid, diethylenetriamine-pentaacetic acid and, for example, polymerisation of a carboxylic acid, the acetic acid, the acetic acid, the acetic acid, the acetic acid, the acidic acid, the acid of which is carboxylic acid, the acetic acid, the acidic acid, the acidic acid, the acidic acid of which is homologous carboxylic acid , Succinic acid, tricarballylic acid, and subsequent saponification, or by condensation of polyamines with a molecular weight of 500 to 10,000 with chloroacetic or bromoacetic salts.

Polymeric carboxylic acids are preferably used as co-builders. These polymeric carboxylic acids include the carboxymethyl ethers of sugar, starch and cellulose.

Among the polymeric carboxylic acids e.g. the polymers of acrylic acid, maleic acid, itaconic acid, mesaconic acid, aconitic acid, methylene malonic acid, citraconic acid and the like. The copolymers of the abovementioned carboxylic acids with one another, e.g. a copolymer of acrylic acid and maleic acid in a ratio of 70:30 and a molecular weight of 70,000, or with ethylenically unsaturated compounds such as ethylene, propylene, isobutylene, vinyl alcohol, vinyl methyl ether, furan, acrolein, vinyl acetate, acrylamide, acrylonitrile, methacrylic acid, crotonic acid etc., such as e.g. the 1: 1 copolymers of maleic anhydride and methyl vinyl ether with a molecular weight of 70,000 or the copolymers of maleic anhydride and ethylene or propylene or furan play a special role.

The co-builders can also contain dirt carriers which keep the dirt detached from the fibers suspended in the liquor and thus inhibit graying. For this purpose, water-soluble colloids, usually of an organic nature, are suitable, such as, for example, the water-soluble salts of polymeric carboxylic acids, glue, gelatin, salts of ether carboxylic acids or ether sulfonic acids of starch or cellulose or salts of acidic sulfuric acid esters of cellulose or starch. Water-soluble polyamides containing acidic groups are also suitable for this purpose. Soluble starch preparations and starch products other than those mentioned above can also be used, e.g. degraded starch, aldehyde starches, etc. Polyvinylpyrrolidone can also be used.

Bleaching agents are especially hydrogen peroxide and derivatives or active chlorine-providing compounds. Sodium perborate hydrates, such as NaBO₂ · H₂O₂ · 3H₂O and NaBO₂ · H₂O₂, are of particular importance among the compounds which serve as bleaching agents and supply H₂O₂ in water. But there are also other H₂O₂ supplying borates. These compounds can be partially or completely replaced by other active oxygen carriers, in particular by peroxyhydrates, such as peroxycarbonates, peroxyphosphonates, citrate perhydrates, urea-H₂O₂- or melamine-H₂O₂-compounds as well as by H₂O₂-delivering peracid salts, e.g. Caroates, perbenzoates or peroxyphthalates can be replaced.

In addition to the customary water-soluble and / or water-insoluble stabilizers for the peroxy compounds according to the invention, they can be incorporated together with these in amounts of 0.25 to 10% by weight, based on the peroxy compound. The are suitable as water-insoluble stabilizers Magnesium silicates MgO: SiO₂ of the composition 4: 1 to 1: 4, preferably 2: 1 to 1: 2 and in particular 1: 1, obtained mostly by precipitation from aqueous solutions. Other alkaline earth metals of appropriate composition can also be used in their place.

In order to achieve a satisfactory bleaching action when washing at temperatures below 80 ° C, in particular in the range from 60 to 40 ° C, bleach activators are advantageously incorporated into the detergent, advantageously in an amount of, based on the H₂O₂-providing compound 5 to 30% by weight.

As activators for H₂O₂ delivering per compounds serve certain, with H₂O₂ organic peracids forming N-acyl, O-acyl compounds, especially acetyl, propionyl or benzoyl compounds, as well as carbonic acid or pyrocarbonate. Useful connections include:
N-diacylated and N, Nʹ-tetraacylated amines, such as
N, N, Nʹ, Nʹ-tetraacetyl-methylenediamine or -ethylenediamine,
N, N-diacetylaniline and N, N-diacetyl-p-toluidine or 1,3-diacylated hydantoins,
Alkyl-N-sulfonyl-carbonamides,
N-acylated cyclic hydrazides, acylated triazoles or urazoles, such as that
Monoacetyl maleic acid hydrazide,
O, N, N-trisubstituted hydroxylamines, such as
O-benzoyl-N, N-succinyl-hydroxylamine,
O-acetyl-N, N-succinyl-hydroxylamine,
Op-methoxybenzoyl-N, N-succinylhydroxylamine,
Op-nitrobenzoyl-N, N-succinylhydroxylamine and
O, N, N-triacetyl-hydroxylamine,
Carboxylic anhydrides, e.g.
Benzoic anhydride,
m-chlorobenzoic anhydride,
Phthalic anhydride, 4-chlorophthalic anhydride,
Sugar esters, such as glucose pentaacetate,
Imidazolidine derivatives, such as
1,3-diformyl-4,5-diacetoxyimidazolidine,
1,3-diacetyl-4,5-diacetoxy-imidazolidine,
1,3-diacetyl-4,5-di-propionyloxy-imidazolidine,
acylated glycolurils, such as
Tetrapropionylglycoluril or
Diacetyl-dibenzoylglycoluril,
dialkylated 2,5-diketopiperazines, such as
1,4-diacetyl-2,5-diketopiperazine,
1,4-dipropionyl-2,5-diketopiperazine,
1,4-dipropionyl-3,6-dimethyl-2,5-diketopiperazine,
Acetylation or benzoylation products of propylene diurea or 2,2-dimethyl-propylene diurea,
the sodium salt of p- (ethoxycarbonyloxy) -benzoic acid and p- (propoxycarbonyloxy) -benzenesulfonic acid and the sodium salts of alkylated or acylated phenolsulfonic acid esters, such as p-acetoxy-benzenesulfonic acid, 2-acetoxy-5-nonyl-benzenesulfonic acid,
2-acetoxy-5-propylbenzenesulfonic acid or the
Isononanoyloxiphenylsulfonic acid.

Active chlorine compounds of inorganic or organic nature can also be used as bleaching agents. The inorganic active chlorine compounds include alkali hypochlorites, which can be used in particular in the form of their mixed salts or addition compounds on orthophosphates or condensed phosphates, such as, for example, on pyro- and polyphosphates or on alkali silicates. If the washing and washing aids contain monopersulfates and chlorides, active chlorine is formed in aqueous solution.

Suitable organic chlorine compounds are, in particular, the N-chlorine compounds in which one or two chlorine atoms are bonded to a nitrogen atom, the third valence of the nitrogen atoms preferably leading to a negative group, in particular to a CO or SO₂ group. These compounds include dichloro- and trichlorocyanuric acid or its salts, chlorinated alkylguanides or alkylbiguanides, chlorinated hydantoins and chlorinated melamines.

Examples of additional auxiliaries are:
Suitable foam regulators are, especially when using surfactants of the sulfonate or sulfate type, capillary-active carboxy- or sulfobetaines and the above-mentioned nonionics of the alkylolamide type. Fatty alcohols or higher terminal diols are also suitable for this purpose.

A reduced foaming power, which is particularly desirable in machine washing, is often achieved by combining different types of surfactants, for example sulfates and / or sulfonates with nonionics and / or with soaps. In the case of soaps, foam attenuation increases with the degree of saturation and the C number of the fatty acid ester; Soaps of saturated C₂₀-C₂₄ fatty acids are therefore particularly suitable as foam suppressants.

The non-surfactant-like foam inhibitors optionally include chlorine-containing N-alkylated aminotriazines, which are obtained by reacting 1 mol of cyanuric chloride with 2 to 3 mol of a mono- and / or dialkylamine having 6 to 20, preferably 8 to 18, carbon atoms in the alkyl radical. Propoxylated and / or butoxylated aminotriazines, e.g. Products obtained by adding 5 to 10 moles of propylene oxide to 1 mole of melamine and further adding 10 to 50 moles of butylene oxide to this propylene oxide derivative.

Also suitable as non-surfactant-like foam inhibitors are water-insoluble organic compounds, such as paraffins or halogen paraffins with melting points below 100 ° C., aliphatic C₁₈ to C₄₀ ketones and aliphatic carboxylic acid esters which are present in the acid or alcohol residue, optionally also in each of these two residues, at least Contain 18 carbon atoms (eg triglycerides or fatty acid fatty alcohol esters); they can be used especially with combinations of surfactants of the sulfate and / or sulfonate type with soaps to dampen the foam.

The detergents can contain optical brighteners for cotton, for polyamide, polyacrylonitrile or polyester fabrics. Suitable optical brighteners are, for example, derivatives of diaminostilbenedisulfonic acid for cotton, derivatives of 1,3-diarylpyrazolines for polyamide, quaternary salts of 7-methoxy-2-benzimidazolyl- (2ʹ) -benzofuran or of derivatives from the compound class of 7- [1ʹ, 2ʹ, 5ʹ-triazolyl- (1ʹ)] - 3- [1ʺ, 2ʺ, 4ʺ-triazolyl- (1ʺ)] - coumarins for polyacrylonitrile. Brighteners suitable for polyesters are, for example, products from the compound class of substituted styriles, ethylenes, thiophenes, naphthalenedicarboxylic acids or derivatives thereof, stilbenes, coumarins and naphthalimides.

The substances known per se to the person skilled in the art can be used as further auxiliaries or formulation auxiliaries, e.g. Solubilizers, such as xylene or cumene sulfonates, adjusting agents, such as sodium sulfate, enzymes or perfume oils.

The washing and cleaning agents according to the invention can, for example, be powdery or liquid.

example 1 A. Preparation of Serine-N, N-Diacetonitrile

100 g (1 mol) of 30% strength by weight aqueous formaldehyde solution are initially introduced, and a solution of 52 g (0.5 mol) of serine in 250 g of water, in which: a pH of 8.5 was previously set with 37 g of 40% NaOH.

After stirring for a further 30 minutes at 25 ° C., 27 g (1 mol) of hydrocyanic acid are added dropwise at 15 to 20 ° C. in the course of 1.5 hours. The mixture is then stirred at 20 ° C for 30 minutes until starting materials are no longer detectable and complete conversion is achieved.

98 % d.Th.) erhalten. Die durch Gefriertrocknung isolierte Verbindung hat keinen scharfen Schmp. und schmilzt unter Zersetzung.
455 g of an approximately 20% solution of serine-N, N-diacetonitrile (

98% of theory). The compound isolated by freeze-drying has no sharp melting point and melts under decomposition.

Analysis:

C₇H₉N₃O₃ (183.16) calc.
C 45.90% H 4.95% N 22.94% O 26.21%
found
C 45.43% H 5.08% N 22.72% O 26.76%

B. Preparation of Serine-N, N-Diacetic Acid Trisodium Salt

The aqueous solution of serine-N, N-diacetonitrile prepared under 1 is added dropwise to 102 g (1.02 mol) of 40% strength by weight aqueous sodium hydroxide solution at 95 to 110 ° C. in the course of 1 hour. After stirring for a further 3 hours at 100 ° C., no more ammonia development is found (total 0.94 mol).

94 % d.Th.). Der Schmp. des isolierten Salzes liegt über 300°C.The result is a clear, yellow, approx., 30% by weight aqueous solution of serine-N, N-di-acetic acid trisodium salts. (Weight: 390 g (

94% of theory). The melting point of the isolated salt is above 300 ° C.

C. Preparation of Serine-N, N-Diacetic Acid

86 % d.Th.) Serin-N,N-diessigsäure vom Schmp. 171 bis 173°C, vgl. s. Korman et al., J. Biol. Chem. 221, S. 116 (1956).The aqueous solution of serine-N, N-di-acetic acid trisodium salt produced under B is concentrated to about 50% by weight under reduced pressure (water jet pump). A pH of 2 is set with concentrated hydrochloric acid. The solution is then added dropwise to 4 times the volume of methanol. The colorless precipitate which has separated out is filtered off and washed again with methanol. After drying, 98 g (

86% of theory) Serine-N, N-diacetic acid, mp. 171 to 173 ° C, cf. s. Korman et al., J. Biol. Chem. 221, p. 116 (1956).

Example 2

30 g (0.5 mol) of glycol aldehyde are placed in 100 g of water and a solution of 66.6 g (0.5 mol) of iminodiacetic acid in 120 g of water is added dropwise at 25 ° C. in the course of 30 minutes % by weight aqueous sodium hydroxide solution was adjusted to a pH of 7.

13.6 g (0.5 mol) of liquid hydrocyanic acid are then added dropwise at 15 to 20 ° C. and a pH of 7 in 45 minutes. The mixture is then stirred at 30 ° C for 5 hours.

For the saponification, 51 g (0.5 mol) of 40% strength by weight aqueous sodium hydroxide solution are then added to the yellow solution obtained. The ammonia formed is removed at 90 ° C. within 4 hours.

An orange-colored solution of serine-N, N-di-acetic acid trisodium salt is obtained, from which the acid is released in accordance with Example 1C.

The yield is 65% of theory

Example 3

134 g (1 mol) of nitrilotriacetonitrile are dissolved in 450 g of ethanol. A pH of 9.5 is set with triethylamine (measured on a sample in 10% by weight aqueous solution).

150 g (1.5 mol) of 30% strength by weight aqueous formaldehyde solution are then added dropwise at 75 ° C. in the course of 3 hours while the pH is kept constant.

After stirring for 4 hours at 75 ° C., the solution of hydroxymethylnitrilotriacetonitrile obtained is added dropwise to 300 g (3 mol) of a 40% strength by weight aqueous sodium hydroxide solution heated to 100 ° C. within 30 minutes. For saponification, the mixture is heated at 100 ° C. for 4 hours until no more ammonia escapes.

The free acid according to Example 1C is obtained from the solution of serine N, N-di-acetic acid trisodium salt obtained.

The yield is 55% of theory

The tripotassium and triammonium salts obtained from the free serine-N, N-diacetic acid each have mp of above 300 ° C.

Application properties I. Determination of the iron complexing capacity

The inhibitory effect of complexing agents on the precipitation of iron (III) hydroxide is determined by turbidity titration. The active substance to be investigated (W.S.) is presented and titrated in an alkaline solution with iron (III) chloride solution until it becomes cloudy.

The titration is carried out automatically using a titroprocessor; the light transmittance of the solution is monitored with an optical fiber photometer. The end point of the titration is indicated by the appearance of a turbidity. It indicates the amount of iron bound and is a measure of the strength of the complex formed compared to iron hydroxide.

For compounds with a dispersing effect on iron hydroxide, discoloration usually occurs before the end point is reached.

The extent of the discoloration (caused by colloidally dispersed iron hydroxide) gives an indication of the tendency of the complex formed to disassociate. A rough measure of this is the slope of the titration curve before the equivalence point is reached. It is measured in% transmission / ml FeCl₃ solution. The reciprocal values thus indicate the strength of the complexes.

Execution regulation:

1 mmol of the substance to be examined (W.S.) is dissolved in 100 ml of dist. H₂O solved. The pH is adjusted to 10 with 1N NaOH and kept constant during the titration. Titrate at room temperature at a rate of 0.4 ml / min. with 0.05 m FeCl₃ solution.

The complexing capacity is expressed as:

II. Testing of sodium perborate stabilization in wash liquors principle

The hydrogen peroxide responsible for the bleaching action in detergent formulations containing sodium is catalytically decomposed by heavy metal ions (Fe, Cu, Mn). This can be prevented by complexing the heavy metal ions. The peroxide-stabilizing effect of the complexing agents is checked via the residual peroxide content after warm storage of a wash liquor containing heavy metals.

The hydrogen peroxide content is determined before and after storage by titration with potassium permanganate in acid solution.

To test for perborate stabilization, two detergent formulations are used, the decomposition during hot storage being carried out by adding heavy metal catalysts (2.5 ppm mixture of 2 ppm Fe³⁺, 0.25 ppm Cu²⁺, 0.25 ppm Mn²⁺).

1. Phosphate-containing formulation Composition (in% by weight):

19.3% sodium C12 alkylbenzenesulfonate (50% by weight aqueous solution)
15.4% sodium perborate · 4 H₂O
30.8% sodium triphosphate
2.6% copolymer of maleic acid and acrylic acid (50:50, average MW 50,000)
31.0% sodium sulfate, anhydrous
0.9% complexing agent or comparative compound according to the invention

The detergent concentration is 6.5 g / l using water at 25 ° dH. Storage is at 80 ° C for 2 hours.

2. Reduced phosphate formulation Composition (in% by weight):

15% sodium C12 alkylbenzenesulfonate (50% by weight aqueous solution)
5% adduct of 11 moles of ethylene oxide with 1 mole of tallow fatty alcohol
20% sodium perborate · 4 H₂O
6% sodium metasilicate · 5 H₂O
1.25% magnesium silicate
20% sodium triphosphate
31.75% sodium sulfate, anhydrous
1% complexing agent according to the invention or comparative compound

The detergent concentration is 8 g / l using water at 25 ° dH. Storage is at 60 ° C for 1 hour.

III Determination of the calcium binding capacity Measuring principle

The inhibitory effect of complexing agents or dispersing agents on the precipitation of calcium carbonate is determined by turbidity titration. The substance to be examined is presented and titrated with calcium acetate solution in the presence of sodium carbonate. The end point is indicated by the formation of the calcium carbonate precipitation. By using a sufficient amount of sodium carbonate it is ensured that the measurement delivers a correct result even if the effect is based not only on complexing the calcium ions but also on the dispersion of calcium carbonate. If too small amounts of sodium carbonate are used, there is a risk that the dispersibility of the product will not be exhausted; in this case the titration end point is determined by the precipitation of the calcium salt of the investigated compound.

During the titration, the change in light transmittance is monitored using an optical fiber photometer. In the latter, a light beam directed into the solution via glass fibers is reflected on a mirror and the intensity of the reflected light is measured.

Reagents:

0.25 m Ca (OAc) ₂ solution
10% Na₂CO₃ solution
1N NaOH solution
1% hydrochloric acid

Execution:

1 g W.S. in the form of the trisodium salt is distilled in 100 ml. H₂O solved. Then 10 ml of 10% Na₂CO₃ solution are added. At room temperature (RT) and a constant pH during the titration of 11 and at 80 ° C with a pH of 10 is with 0.25 m Ca (OAc) ₂ solution continuously at 0.2 ml / min titrated automatically.

Calculation:

Amount mg CaCO₃ / g W.S. = Consumption of CA (OAc) ₂ solution in ml x 25. With automatic titration, the 1st breakpoint of the titration curve is the end point.

The results obtained are summarized in Table 1:

It follows from the results that the calcium binding capacity, especially at 80 ° C., is significantly better than that of sodium triphosphate and is lower than that of the sodium salts of NTA and EDTA, whereby the smaller molecular weight of NTA should be taken into account. The binding capacity for iron is almost three times higher than for NTA and EDTA.

The strength of the complex formed, expressed in% transmission / ml FeCl₃ solution, is many times greater than that of the complex of ethylenediaminetetraacetic acid.

The particularly surprising effect lies in the excellent perborate stabilization for the N-containing and relatively low molecular weight compound to be used according to the invention.

When used as a scaffold, good washing results are obtained with standard detergent formulations, in particular with regard to the incrustation inhibition, measured on the ash content.

Claims (8)

1. Process for the preparation of compounds of formula I.

in which Y represents the radical -COOH, which is optionally in the form of an alkali metal, ammonium or substituted ammonium salt, or represents the radical -CN and
X is a hydroxyl group, the carboxylic acid group thereby present optionally being in the form of an alkali metal, ammonium or substituted ammonium salt, or a radical -NR³R⁴, in which R³ and R⁴ are identical or different and represent a hydrogen atom or an alkyl radical with 1 to 4 C. -Atoms stand,
means, characterized in that 1 mol of serine, optionally in the form of an alkali salt, or the acid amide, optionally substituted on the amide nitrogen atom by one or two alkyl radicals having 1 to 4 carbon atoms, in water, an organic solvent or their mixtures with 2 up to 2.6 moles of formaldehyde and 2 to 2.3 moles of liquid hydrocyanic acid at temperatures from 0 to 45 ° C. or with 2 to 2.3 moles of alkali metal cyanide at temperatures from 40 to 100 ° C. and any amide and nitrile groups present hydrolyzed in the presence of an acid or base and, if appropriate, isolating the free acid or a salt of the formula I. 2. A process for the preparation of compounds of the formula I, the radical -COX representing a nitrile group, serine-N, N-diacetic acid and its salts, characterized in that glycol aldehyde is reacted with a compound of the formula II
HN (CH₂-Y) ₂ II
in which Y has the meanings given for formula I and in addition can be a radical -COOR¹, in which R¹ is an alkyl radical having 1 to 4 carbon atoms, and with liquid hydrocyanic acid or an alkali metal cyanide in water, an organic solvent or their Mixtures at temperatures of 10 to 100 ° C and optionally hydrolyzed the nitrile groups and amide or ester groups present in the presence of an acid or base and optionally isolated the free acid or a salt according to formula I. 3. Process for the preparation of compounds of formula I with the meaning nitrile for the radicals Y and -COX, the serine-N, N-diacetic acid and their salts, characterized in that nitrilotriacetonitrile with formaldehyde with base catalysis in a pH value Reacts range from 7.5 to 12 at temperatures from 0 to 100 ° C, possibly hydrolyzed the nitrile groups in the presence of an acid or base and optionally isolates the free acid or a salt of formula I. 4. Use of serine-N, N-diacetic acid, its sodium, potassium, ammonium or organic amine salts as a complexing agent for heavy metal and / or alkaline earth metal ions. 5. Use of serine-N, N-diacetic acid, its sodium, potassium, ammonium or organic amine salts as builders in detergents and cleaning agents. 6. Use of serine-N, N-diacetic acid, its sodium, potassium, ammonium or organic amine salts in detergents and cleaning agents as bleach stabilizers. 7. Detergents and cleaning agents containing serine-N, N-diacetic acid, their sodium, potassium, ammonium acid or organic amine salts in an amount of 0.01 to 20% by weight, based on the total weight. 8. Serine-N, N-diacetonitrile as an intermediate for the production of Serine-N, N-diacetic acid and its salts.