WO1997030063A2

WO1997030063A2 - Preparation of surface-active compounds based on lactose

Info

Publication number: WO1997030063A2
Application number: PCT/NL1997/000070
Authority: WO
Inventors: Robert Willem Frederik Kammelar; Henricus Johannes Antonius Rita Timmermans; Petronella Johanna Frikkee-Dekker; Jacobus Van Haveren
Original assignee: Coöperatieve Weiproduktenfabriek 'borculo' W.A.
Priority date: 1996-02-19
Filing date: 1997-02-19
Publication date: 1997-08-21
Also published as: AU1735997A; CA2245222A1; JP2000504719A; EP0882056A2; WO1997030063A3; BR9707558A

Abstract

Methods are described for preparing surface-active lactose derivatives with lactose being aminated reductively, in a one-step process, using a C1-C20 alkylamine and hydrogen in the presence of a transition metal catalyst; or lactose being aminated by means of reactive processing per part by weight of lactose, a C1-C20 alkylamine being used and the N-alkyl-lactosylamine being reduced; or lactose being reacted with an alkylamine and the N-alkyllactosyl-amine obtained being acylated; lactose being reacted with an acylamine or a urea; and/or a lactylamine or lactosylamine being oxidised, at least 2, in particular 4-50, primary alcohol groups per 100 being converted into a carboxylic acid; and/or a lactylamine or lactosylamine being converted into an amine acid. The derivatives are useful as surfactants, emulsifiers and dispersants. Instead of lactose derivatives of other galacto-oligo-saccharides can also be prepared and used.

Description

PREPARATION OF SURFACE-ACTIVE COMPOUNDS BASED ON LACTOSE

The invention relates to a method for preparing surface-active compounds based on aminated galacto-oligosaccharides such as lactose.

French Patent Application 2661413 discloses the preparation of N-alkyl- lactosylamines and N-alkyllactylamines. The N-alkyllactosylamines are prepared by reacting lactose with an N-alkylamine in water/2- propanol. The amount of solvent is about 15 times that of the amount of lactose, and the reaction takes about 24 hours. The yield is between 48 and 74%. The N-alkyllactylamines are prepared, in a second step, from the N-alkyllactosylamines, either by catalysed hydrogenation (yield about 40%, incomplete conversion), or by reduction with sodium borohydride (yield 57- 90%). The total conversion of lactose into alkyllactylamine, according to this known method, is about 25% for the catalysed hydrogenation and 31-67% for the reduction with borohydride. This method has the drawback that low yields are obtained, particularly if expensive chemicals such as sodium borohydride are not used. Additionally, FR-A-2661413 and EP-A-515283 describe the preparation of

N-acetyl-N-alkyllactosylamines via the reaction of N-alkyilactosylamine with acetic anhydride. The reaction is carried out in a large amount (about 13 times the amount of lactosylamine) of aprotic solvent such as dimethylformamide or dimethyl sulphoxide under argon. The yield is in the order of 35-50%. A drawback of this method is the low yield and the use of solvents which arc undesirable, certainly for alimentary applications. A further drawback of the known methods for the preparation of amines derived from lactose is that they do not lend themselves to continuous operation.

Lammers et al (Tetrahedron, 27, 8103-8116, 1994) describe the reductive amination of galactose, mannose and glucose with propylamine, ethylenediamine and 1,3-diaminopropane with a platinum catalyst. Galactitol (mannitol, glucitol) is formed as an important byproduct (about 15%) when an equivalent amount of amine used; the product yield is 80-85 % when 5 equivalents of amine are used. Such results are not attractive for a reaction with long chain alkylamines.

It is an object of the invention to provide improved methods for the preparation of lactose derivatives known per se, which are surface-active, in particular detergent and/or emulsifying, and to provide novel surface-active derivatives of galacto-oligosaccharides. The term "galacto-oligosaccharides" herein refers to reducing sugars and sugar derivatives which include at least one galactose unit to which one or more further monosaccharide units are bound. An important example of this is lactose (β-galactosyl-glucose: βGal-l,4-Glu). Other examples are oligosaccharides based on lactose to which one or more subsequent galactose units are linked, for example by the reaction of lactose with a β-galactosidase (βGal_n-Glu, n = 2-6). Further examples are βGal-l,6-Gal and melibiose (αGal-l,6-Glu).

Correspondingly, the terms galactoglycosylamine and galactoglycitylamine herein refer to a galacto-oligosaccharide whose reducing hydroxyl group, not necessarily on the galactose unit, has been replaced by an amine group, without reduction or by means of reduction, respectively. For the sake of simplicity, the invention is hereinafter illustrated with reference to lactose and lact(os)ylamines, but in each case this should be understood as equally implying other galacto-oligo¬ saccharides as defined hereinabove or the corresponding amines. Where the present description refers to a C_j-C_j^ or C_j-C₂o alkyl group, this group may be saturated or unsaturated, and includes an alkyl, alkenyl, alkynyl, alkadienyl or alkapolyenyl group, each of which may or may not be branched and has 1-19 or 1-20 carbon atoms and in which, at the same time, an aromatic or alicyclic group may be present. Arbitrary examples are methyl, propargyl, heptyl, isooctyl, undecyl, pentadecenyl, hexadecyl, octadecadienyl, nonadccatrienyl, 1-methylcyclo- hexyl, phenethyl and p-nony iphenyl. These alkyl groups also comprise mixtures of alkyl groups. These may have an average between e.g. 2 and 20 carbon atoms, in particular between 10 and 18 carbon atoms. Such mixtures arc accessible in the form of mixed alkylamines, for example tallow amine (1% C₁₂, 4% C₁₄, 31% C₁₆, 64% C₁₈), cocoamine (5% C₈, 6% C₁₀, 50% C₁₂, 19% C₁₄, 10% C₁₆, 10% C₁₈), and oleylamine (1% C₁₂, 4% C₁₄, 12% C₁₆, 82% C₁₈).

In a first aspect, the invention relates to a method for preparing surface- active, detergent, dispersant and/or emulsifying lactose derivatives, lactose being aminated reductively, in a one-step process, using a CI~C_2Q alkylamine which may or may not be saturated and hydrogen in the presence of a transition metal catalyst.

An advantage of this method is that considerably higher yields are obtained than with the known two-step processes, and that no expensive reagents such as sodium cyanoborohydrides are required. This method preferably employs an equivalent amount or a slightly sub- stoichiometric amount or slight excess of alkylamine, in particular 0.8-1.5 equivalents. A transition metal used may be selected from the metals known per se for this purpose, such as nickel, palladium, platinum, ruthenium or other metals from group VIII, especially palladium. Optionally, the transition metal may be applied to a support such as carbon. The solvent used may, for example, be water, an alcohol or an alcohol-water mixture. It was found, surprisingly, that if a slightly substoichiometric amount (i.e. less than 1.00 equivalent, for example 0.85-0.98 equivalent), based on lactose, of alkylamine is used, the lactose is not reduced to lactitol, the work-up of the product thus being simplified.

In a second aspect, the invention relates to a method for preparing surfactant lactose derivatives, lactose being aminated by means of reactive processing using a C₁-C_2Q alkylamine, and the N-alkyllactosylamine being reduced in a second step.

The term "reactive processing" herein refers to a reaction involving little or no solvent, in general less than 4 parts by weight and in particular less than 3 parts by weight of solvent per part by weight of lactose, with mechanical blending. Blending takes place in such a way that a reaction occurs. Optionally, the reaction may be carried out with heating or in the melt, one particular option being that of employing an extrusion process. Reactive processing is known per se, for example for the preparation of starch derivatives (sec, for example, Tomasik ct al., Starch/Stάrke 47 (1995), 96-99, and Narkrugsa ct al., Starch/Stάrke 44 (1992), 81-90). The present method preferably employs moderate temperatures, for example between 10 and 100°C. Suitable solvents are solvents containing carbon, hydrogen and oxygen only, such as water, alcohols especially C_j-C₄ alkanols such as methanol, ethanol, isopropanol and methoxyethanol, and relatively polar ethers such as tetrahydrofuran, dioxane, dimethoxyethane, as well as mixtures of water and an alcohol and/or an ether. Reactive processing rapidly (in less than 1/2 hour) leads to high yields of alkyllactosylamine. Important advantages of reactive processing are that the reaction can be a continuous process, that the processes arc more energy-efficient and less solvent or none at all is consumed, so that fewer work-up steps are required.

The N-alkyllactosylamine thus obtained is less suitable for use as such, since it is relatively unstable. The N-alkyl-lactosylaminc is therefore preferably reduced to an N-acyllactylamine or acylated to an N-alkyl-N-acyllactosylamine. The reduction to N-alkyllactylamine can be effected by means of hydrogen in the presence of a transition metal catalyst or alternatively by means of a hydride such as sodium borohydride. The catalysed hydrogenation is preferably carried out at elevated temperature, for example between 30 and 80°C. The reduction with sodium boro- hydride can be carried out at room temperature. The reduction leads to a yield of 70% or more.

According to the aspects described hereinabove of the invention, N-alkyl- galactoglycitylamines having the formula: Sar-NH-R¹ are thus prepared, where Sar represents the radical of a reduced di- or oligosaccharidc which contains at least one galactose unit, and R represents a C_j-C₂₀ alkyl group which may or may not be saturated. With a view to the surface-active properties, derivatives are preferred in which R represents a C₇-C ₀ group, in particular a C₁₀-C₁₈ group, such as a hexa¬ decyl group. Especially preferred are mixtures of alkyl groups having an average of 12-18 carbon atoms. Another aspect of the invention relates to a method for preparing surface- active lactose derivatives by a lactosylamine, having been obtained from lactose, being acylated using a C₂-C_2fJ-carboxylic acid anhydride or halide by means of reactive processing.

Said acylation by reactive processing is preferably effected using a solvent containing carbon, hydrogen and/or oxygen only and/or by means of reactive processing (extrusion), at temperatures which may or may not be elevated, such as 10-100°C. Preferably, no solvent is used in reactive extrusion, particularly if the carboxyiic acid anhydride or halide is a liquid. A base may also be added to bind any acid formed. Preferably, a solid base is used such as potassium carbonate or sodium bicarbonate, or optionally a liquid base such as triethylamine. Reactive processing can advantageously be carried out continuously. For acylation without extrusion the preferred solvent is methanol and no base is necessary.

An important advantage of the acylation as described above is that no inconvenient and, for alimentary applications, undesirable solvents such as DMF, DMSO or pyridine need be employed. Furthermore, high and even quantitative yields are obtained, which constitutes an important improvement over the prior art such as EP-A-515283.

The lactosylamine which is the starting material for the above-described acylation can be obtained by reaction of lactose with a C_l-C₂₀ alkylamine in a manner known per se. Said amination can be carried out in water and/or an alcohol, such as isopropanol, as a solvent, for example at a temperature of 30-70°C. The lactosylamine can alternatively be obtained in the above-described manner by reactive processing.

The acylated lactosylamines can be prepared not only by successive amination and acylation, as described above, but also by amidation of lactose. Said amidation is carried out using a C₂-C₂₀-acylamine or using urea or an alkylurea, by means of reactive processing as described hereinabove for the acylation. In the case of amidation of lactose with urea, an alkylation can be carried out subsequently, for example using an alkyl halide, alkyl acetate, alkyl benzoate or alkyl sulphonate, so as to introduce the alkyl group which is required for the surface-active properties.

According to this aspect of the invention, N-acylgalactoglycosylamines having the formula Sac-NR¹-CO-(NH)_m-R² are prepared, in which Sac represents the radical of a reducing di- or oligosaccharide which contains at least one galactose unit, m represents the number 0 or 1, R¹ represents an alkyl group which may or may not be saturated and has 1-20 carbon atoms or. if m=l, a hydrogen atom, and R² represents hydrogen or an alkyl group which may or may not be saturated and has 1-

19 carbon atoms. Preferably, at least one of the groups R¹ and R contains at least 7 and more preferably at least 10 carbon atoms. In particular if m equals 0 and R is a methyl group, or if R² is a hydrogen atom. R¹ preferably contains at least 12 carbon atoms or is a mixture of alkyl groups with an average of 10-18 carbon atoms.

According to the invention N-alkyl-N-acyl-lactylamines can be prepared either by acylation of an N-alkyllactylamine obtained in the above-described manner, for example by means of reactive processing, or by the reduction of an N-alkyl-N- acyllactosylamine, for example using hydrogen/palladium or sodium borohydride. Thus, N-acylgalactoglycitylamines having the formula Sar-NR¹-CO-(NH)_m-R² are prepared, in which Sar represents the radical of a reduced di- or oligosaccharide which contains at least one galactose unit, m represents the number 0 or 1, R¹ represents hydrogen or an alkyl group which may or may not be saturated and has 1-

20 carbon atoms, and R² represents hydrogen or an alkyl group which may or may not be saturated and has 1-19 carbon atoms. Again, at least one of the groups R¹ and R² preferably contains at least 7 and more preferably at least 10 carbon atoms or is a mixture of alkyl groups with an average of 10-18 carbon atoms.

A further aspect of the invention relates to surface-active lact(os)ylamines which, on one or more of the oxygen and nitrogen atoms, carry an alkyl or alkanoyl group substituted by one or more acid groups -COOH, -PO(R⁴)(OH), -PO(OR⁴)(OH), -OPO(R )(OH), -OPO(OR⁴)(OH), -SO₃H or -OSO₃H and having

1-4 carbon atoms, wherein the group -PO(R⁴)(OH), -PO(OR⁴)(OH), -SO₃H may alternatively be bound directly to an oxygen atom. R⁴ here represents a hydrogen atom or a C_j-Cy-hydrocarbon group such as methyl, ethyl, aUyl, butyl, phenyl, cyclohexyl or benzyl. Obviously the acid groups may be present in ionised form, and in particular zwitterions may be involved. These compounds can be prepared, for example, by the reaction of a lactylamine or lactosylamine as described hereinabove with, for example: a haloacetic acid with the formation of an N- or O-carboxymethyl derivative; acrylonitrile followed by saponification with the formation of an N- or O-carboxy- ethyl derivative; a halomethylphosphonic acid with the formation of an O- or N- phosphonomethyl derivative; formaldehyde and an alkylphosphonic acid with the formation of an N-(ethylphosphonicomcthyl) derivative; hydroxymethylsulphonic acid with the formation of a sulphomethyl derivative; chlorocthylsulphonic acid with the formation of an O- or N-sulpho-ethyl derivative; ethylene oxide and chlorosulphonic acid with the formation of an O-sulphatoethyl derivative; chlorosulphonic acid or chlorophosphonic acid with the formation of an O-sulphato or O-phosphato derivative; succinic anhydride with the formation of an O- or N-succinoyl derivative; or maleic anhydride followed by bisulphite with formation of an α- or β-sulpho- succinoyl derivative. Suitable derivatisation methods to introduce the acid groups are described, for example, by Van Havercn ct al., NMR in Biomcdicine, 8, 197-205 (1995), and O'Lenick et al., JAOCS, 73, 935-937 (1996).

In another aspect, the invention relates to a method for preparing surface- active oxidised lactose derivatives, in which an N-alkyllactosylaminc, N-alkyllactyl¬ amine, N-alkyl-N-acyllactylamine or N-alkyl-N-acyllactosylamine is oxidised in such a way that at least some of the primary alcohol groups are converted into a carboxyiic acid. In particular, the aminated lactose derivatives are oxidised in such a way that out of 100 primary alcohol functions at least two are converted into a car¬ boxyiic acid group. Since the aminated lactose derivatives contain two primary alcohol functions per molecule, a product is thus obtained which comprises at least approximately 4 mol% of carboxylated compounds. If desired it is also possible for all the primary alcohol functions to be oxidised to carboxyiic acid functions, but to achieve an appropriate surface-active effect it is generally sufficient if a fraction of the functions is oxidised. An advantage of partially oxidised lactylamines is that their solubility in water is enhanced or that they result in less precipitation. In particular, from 4 to 100% of the primary alcohol groups are oxidised to a carboxyiic acid.

Depending on how the oxidation is carried out, not only the primary alcohol functions but also secondary alcohol functions may be oxidised, giving rise to ketone groups and additionally, possibly, with the carbon-carbon bond being broken, to dialdehyde groups or dicarboxylic acid groups. These functions, too, may contribute to the desired surface-active properties of the derivatives.

The oxidation may be carried out, for example, using molecular halogen (Cl or Br₂) or a hypohalite (usually NaOCl or NaOBr). This oxidation can be carried out in water or a water/alcohol mixture at a pH of 8-10. This oxidation may give rise not only to a conversion of primary alcohol groups but also to oxidation of C₂-C₃-diol groups.

A more selective oxidation of the aminated lactose derivatives can be achieved if the oxidation is carried out with a hypohalite in the presence of a di- tertiary-alkyl nitroxyl compound as a catalyst. The di-t-alkylnitroxyl compound may, for example, be di-t-butylnitroxyl, but in particular is a cyclic compound such as an N-oxylpyrrolidine, -piperidine or -morpholine compound whose carbon atoms next to the nitroxyl group arc methylated and which may additionally contain, for example, methyl or methoxy substituents. Preferentially, 2,2,6,6-tctramethylpiperidine-l-oxyl (TEMPO) is used. The di-t-alkyl-nitroxyl may optionally be prepared in the reaction medium, for example by oxidation of the corresponding di-t-alkylamine with hydrogen peroxide and tungstate. The term "a catalytic amount of nitroxyl" refers to an amount which - after conversion of the nitroxyl radical to the corresponding nitrosonium ion - is less than 10% of the amount required for the oxidation of all the primary hydroxyl groups to carboxyl groups. Preferably, the catalytic amount of nitroxyl, based on the carbohydrate monomer, is 0.01 -2 mol%.

The oxidation of the lactose-amine derivatives may further be carried out using oxygen in the presence of a transition metal catalyst. Thus the oxidation using, for example, platinum on carbon, is found to result in selective oxidation of the primary alcohol groups. This oxidation can likewise be carried out in water or in a water/alcohol mixture, the pH being maintained, for example, between 7 and 10.

Advantageously, the oxidation can also be carried out enzymatically, in particular using galactose oxidase (EC 1.1.3.9), the primary alcohol group of the galactose unit being oxidised selectively and a degree of oxidation between 0 and 100% being achievable.

The abovementioned oxidations can be carried out both with the N-alkyl¬ lactylamines, obtained by reductive amination, for example, and their N-acylated derivatives, and with N-alkyl-N-acyllactosyiamines. In all these cases a product having good surface-active properties is obtained.

The invention also relates to the oxidised lactosc-aminc derivatives which can thus be obtained, in particular those of which at least 2%, more in particular at least 4%, of the primary alcohol groups have been converted into a carboxyiic acid group. The invention further relates to the use of the above-described derivatives as an emulsifier in foods, as a cleaning agent or an emulsifier in textile washing compositions, detergents, dishwasher detergents, bodycarc products, beauty products, shampoos, as a surfactant in inks and paints and the like, or as a dispersant, inter alia for pesticides and the like. Also a combination of products according to the invention can be used. For example, a combination of a nonionic surfactant such as N-octa- decyl-lactylamine or N-hexadccyl-N-acctyllactosylaminc with an anionic surfactant such as N-carboxymethyl-N-hexadccyllactylamine or N-hexadecyl-N-acetyl- lacturonylamine forms an excellent surfactant composition.

For example, a textile washing composition may contain one or more surfactants according to the invention at a level of 1-10 wt.%, together with other conventional constituents such as soaps, optical brighteners, zeolites, enzymes, perborate, builders, anionic polymers, foam regulators etc. For delicate textile it may contain 1-15 wt.% of a surfactant of the invention, 5-25 wt.% of soap, and further fatty acid ethoxylates, alcohols, polyglycols, perfumes and enzymes. A dish-washing composition may contain 1-15 wt.% of a surfactant of the invention and further 5-40 wt.% of other ionic surfactants, 0-10 wt.% of other zwitterionic or amphoteric surfactants, and proteins, polymers, hydrotropics. fragrances and preservatives. A hair cleansing composition or a shower bath composition may contain 1-10 wt.% of a surfactant of the invention, in addition to 1-20 wt.% of optional other surfactants, and further thickeners, perfumes, preservatives, colorants, vitamines etc. A skin cream cream may contain 1-10 wt.% of a surfactant of the invention, and 1-30% of other surfactants, together with optional mineral or ester oils, 1-10 wt.% of consistency improvers, perfumes, colourants, preservatives and the like. An emulsifier composition can contain 15-30 wt.% of non-ionic surfactant in addition to 20-35 wt.% of other non-ionic surfactants, mineral oil (20-45%) and water. An ink composition may contain 1-5 wt.% of a surfactant of the invention, together with optional polymers, humectants, colorants, foam breakers, and biocides. A paint composition may contain 0.5-5 wt.% of a surfactant of the invention, 10-80% of a resin, and further components such as pigments, reactive diluents, solvents, driers, fillers, extenders and additives.

To show the utility of the compounds according to the invention, table 1 lists the critical micelle concentrations (CMC) of some alkyllactylamines prepared accord¬ ing to the invention. Table 2 lists the surface tension (ST) as a function of the concentration of hexadecyllactylaminc.

Table 1 CMC values and corresponding surface tension (ST) of alkyllactylamines

Compound CMC (mM) CMC (g/1) ST at CMC

(mN/m) octyllactylamine 42 19.1 31.2 decyllactylamine 37 18.9 38.0 dodecy 1 lacty lamine 9.8 4.7 35.4 hexadecyl-lactylamine 0.14 0.71 37.3

N-acetyl-N-hexadecyl- 0.042 0.025 38.3 lactosylamine

N-carboxymethyl-N- 0.023 0.015 37.4 hexadecyllactylamine Iabje_2 ST of hexadecyllactylamine as a function of the concentration log (concentration, M) ST (mN/m)

-4.5 62

-4.3 53

-4.0 44

-4.0 39

-3.2 39

-3.0 38

Preparative Example 1. Synthesis of dodecyllactosylamine

In 60 ml of H₂O, 10.76 g (30.0 mmol) of lactose were dissolved with heating (up to 50°C). A solution of 9.25 g of dodecylamine (49.9 mmol, 1.66 equivalents) in 100 ml of 2-propanol was added to this. The clear solution was stirred overnight at room temperature and then heated to 60°C for 30 minutes. The solution was subjected to evaporation on the rotary evaporator. The residue was taken up in 40 20 (v/v) ethanol/toluene and again subjected to evaporation so as to completely remove the water. The product was crystallised from 100 ml of ethanol and washed with diethyl ether. The product was obtained with a yield of 90%. The ^-C-NMR spectrum (DMSO-d₆) shows that in a DMSO solution the dodecyllactosylamine is present in the form of a closed ring, in view of the chemical shift of the C₁ atom of the glucose unit (δ = 90.7 ppm). Furthermore, the product is found to have crystallised in probably just one anomeric form (probably the β form) as only one signal of the C atom of the glucose unit is present in the spectrum.

¹³C-NMR (DMSO-d₆, ref. (CD₃)₂SO δ = 39.5 ppm): δ 103.9 ppm (Cl, gal), δ 90.7 ppm (Cl, glu), δ 81.4 - 68.3 ppm (C2 - C5), δ 60.0 and 60.5 ppm (C6), δ 45.7 ppm (HN-CH₂), δ 31.3 - 22.1 (C2-C11, dodecyl tail), δ 13.9 (CH₃).

Preparative Example 2. Reduction of dodecyllactosylamine using Pd/C

1.03 g (2.02 mmol) of dodecyllactosylamine were dissolved in 250 ml of ethanol. To this solution, 104 mg of 10% Pd/C were added. After 21 hours at 50°C under a hydrogen pressure of 2.8 bar in a Parr apparatus the reduction was about 75% complete according to the ¹³C-NMR spectrum. After 40 hours the reaction was complete (100%). Work-up resulted in a pale yellow solid being obtained. Its

Example 1. One-step procedure for the synthesis of N-octyllactylamine Lactose (10.26 g, 30 mmol) was dissolved in 10 ml of warm water. To this, 4.65 g of octylamine (36 mmol, 1.2 eq) in 70 ml of 2-propanol and 750 mg of 10% Pd C were added. The reaction mixture was hydrogenated in a Parr apparatus (3.5 bar, 50°C) overnight. A sample was taken by a few ml of reaction mixture being filtered through celite and the solvent being evaporated. ¹³C-NMR showed that 60-70% of the lactose had been converted to the N-octyllactylamine, the other constituents being lactose and octyllactylamine. ¹³C-NMR (DMSO-d₆) δ (ppm); 104.3 (Cl, gal), 80.9, 76.3, 73.9,

71.8, 71.5, 70.4, 69.5, 69.1 (C2-C5 gal and glu unit), 63.4. 63.0. 61.86, 61.4 (C6 gal, glu), 52.7 and 50.1 (CH₂-N- Cl glu and Cl octylamine), 32.1, 29.7, 29.5, 27.6, 25.9,

22.9, 14.7 (C2-C8 octyl chain). Example 2. Synthesis of hexadecyl lactosylamine by reactive processing

Lactose (53 g, 147 mmol) was introduced, together with hcxadecylamine (57 g, 183 mmol), 46 g of water and 64 g of 2-propanol, into a Haacke Rhcocord 50 kneader. The mixture was heated to 68°C and then kneaded for 15 minutes at a speed of 33 φm. Analysis (¹ C solid-phase NMR) showed that 60-70% of the lactose had been converted to hexadecyllactosylaminc.

Example 3. Synthesis of N -acetyl -N-hexadecyllactosylamine by reactive processing.

Hexadecyllactosylamine was processed, with a throughput of 2 kg h, on a Werner and Pfleiderer ZKS 25 co-rotating twin-screw extruder. Water was injected into the extruder with a throughput of 1.3 kg/h. The total length of the extruder was 28D, with a diameter D of 25 mm. At a distance of 12D, acetic anhydride was added with a throughput of 0.55 kg/h, as was sodium bicarbonate with a throughput of 0.45 kg/h. A speed of 50 φm was used. With the aid of a dye, the average residence time of the product in the extruder was found to be about 3 minutes. The temperature profile set over the extruder was 40-60-60-70-70°C. At the extruder head the temperature measured of the material was 72°C. Analysis by ^L C-NMR showed that complete conversion to N-acyl-N-hexadecyl lactosylamine had occurred. Example 4. Oxidation of dodecyllactylamine with bleach

Dodecyllactylamine (0.5 g, 0.98 mmol) was dissolved in 50 ml of water. 0.4 ml (0.21 mmol) of a sodium hypochlorite solution containing 4% of active chlorine was set to a pH of 9 and added to the dodecyllactylamine solution, after which the pH was maintained at 9 by means of 1 M NaOH. After the oxidation reaction was complete,

1 "X the reaction mixture was neutralised and concentrated. C-NMR showed that a partially oxidised alkyllactylamine had formed, primary alcohol groups having been oxidised at the same time and charge having been introduced into the molecule.

Example 5. Oxidation of dodecyllactylamine using hypochlorite/hypobromite and TEMPO

Dodecyllactylamine (0.5 g, 0.98 mmol), TEMPO (1 mg, 0.007 mmol) and 78 mg (0.38 mmol) of NaBr were dissolved in 50 ml of water. 1.9 ml of a sodium hypo¬ chlorite solution containing 4% of active chlorine were brought to a pH of 7 and added to the dodecyllactylamine solution, after which the pH was maintained at 7 by the addition of 1 M NaOH with the aid of a pH-stat. After the oxidation reaction was complete, the reaction mixture was concentrated. ^{, ?}C-NMR showed that an oxidised dodecyllactylamine had been obtained, the oxidation primarily having taken place at the primary alcohol groups of the dodecyllactylamine.

Example 6. Oxidation of dodecyllactylamine using Pt/C and oxygen 0.1 g of 5% Pt/C was added to 25 ml of H₂0. Dodecyllactylamine (0.5 g, 0.98 mmol) was dissolved in 30 ml of H₂O and added to the Pt/C. The reaction mixture was brought to a pH of 9, and oxygen was passed through the mixture. After the reaction was complete, the catalyst was filtered off and the reaction mixture was concentrated to dryness. ¹³C-NMR showed that an oxidised dodecyllactylamine had been obtained, the oxidation primarily having taken place at the primary alcohol groups of the dodecyllactylamine.

Example 7. Enzymatic oxidation of decyllacrylamine

Decyllactylamine (10.0 mg, 0.21 mmol) was dissolved in 5 ml of 10 mM phosphate buffer (pH = 7.0), followed by the addition of 30 mg of galactose oxidase (EC 1.1.3.9) and 125 μl of catalase. The mixture was incubated at 37°C for 24 hours. Then the mixture was centrifuged off and the supernatant was concentrated. C-NMR indicated that about 50% of the decyllactylamine had been converted, the primary alcohol group of the galactose unit having been oxidised selectively. Example 8. N -Acetyl -N-hexadecyl lactosylamine

N-Hexadecyllactosylamine (20.1 g, 35.4 mmol) was dissolved in 1000 ml methanol at 60°C, and 10.83 g (106 mmol, 3.0 eq.) of acetic anhydride was added dropwise within 3 minutes. The reaction was complete after 2 hours and the reaction mixture was worked up by removing the solvent, acetic acid formed and the excess of acetic anhydride using a rotavapor. The product was purified by stirring overnight in 500 ml of acetone and separating it by filtration. The product was decolorised with activated carbon in methanol. The isolated yield was 50%; purity > 95%.

Example 9. Preparation of hexadecyllactylamine 5.00 g (13.88 mmol) of lactose monohydrate were dissolved in 120 ml of water. To this solution, a solution of 3.05 g (12.63 mmol, 0.91 equivalent) of hexadecylamine in 200 ml of 2-propanol was added. This solution, together with 502 mg of Pd/C, was introduced into a Parr apparatus at 50°C under a hydrogen pressure of 2.8 bar. After 40 hours the reaction was stopped. ¹³C-NMR showed that hexadecyllactylamine had formed, but hexadecylamine was no longer present and that the remaining lactose had not been reduced to lactitol. The 2-propanol in the reaction mixture was distilled off. Then the product was crystallised from the aqueous phase, a pure product being obtained in a yield of 60%.

Example 10. N -Carboxymethyl ^' -hexadecyllactylamine 17.17 g (30.24 mmol) of N-hexadecyllactylaminc were suspended in 350 ml of water.

The pH of the suspension was 8.1. By means of 1 M NaOH solution and a pH-stat, the pH of the suspension was raised to 10. Then 10.5 g (75.6 mmol, 2.5 eq) of bromoacetic acid were added by the spoonful, the pH being maintained at 10. Then the reaction mixture was stirred at 60°C for 4 hours, a clear solution being formed. Then the reaction temperature was raised to 70°C. After a total reaction time of 6.5 hours, 34.1 ml of 1 M NaOH solution (1.1 cq based on N-hexadccyllactylamine) had been consumed, and the reaction was stopped by neutralisation with 4 M hydrochloric acid. A small portion of the solution was boiled down to dryness in the presence of 2-propanol and characterised by means of ^J" C-NMR spectroscopy. This showed that N-hexadecyllactylamine had been completely converted into N-carboxymethyl-N- hexadecyllactylamine. The reaction product was purified further by precipitation from 100 ml of water in 660 ml of acetone. The precipitate was filtered off and dried. Yield 65%. ¹³C-NMR (DMSO-d₆), δ(ppm): 171.4 ppm (C=O), 104.4 ppm (Cl, gal), 80.4- 70.2 ppm (C2-C5, gal and glu unit), 63.5 and 62.6 ppm (C6, glu and gal unit), 58.5- 57.5 (N-CH , carboxymethyl group, Cl glu unit and Cl hexadecyl group), 33.5-15.3 (C2-C16, hexadecyl group).

Example 11. Preparation of 6,6' -dicarboxy-N -acetyl -N-hexadecyllactosylamine N-Acetylhexadecyllactosylamine (0.502 g, 0.826 mol) was dissolved in 40 ml of water, and the solution was cooled to 1°C. NaBr (69.6 mg, 0.676 mmol, 0.82 eq.) and TEMPO (1.93 mg, 0.012 mmol, 0.015 eq.) were added. 6.5 ml of a sodium hypo¬ chlorite solution (0.56 M) (3.67 mmol, 4.4 eq.) were cooled to 1°C and brought to a pH of 10 using 4 M HCl. The solution was added to the reaction mixture at once, the mixture turning green-yellow. The pH was maintained at 10 by the addition of 1 M NaOH with the aid of a pH-stat. After 50 minutes the solution was colourless and no more NaOH was used. Ethanol (10 ml) was added to the reaction mixture resulting in a white precipitate. The solvent was removed after neutralisation using a rotating evaporator. The yield was 90% of white solid. C-NMR confirmed the structure and showed that the primary hydroxyl groups were completely oxidised.

Example 12. Emulsifying activity

To 10 ml of a 2 wt.% solution of N-alkyl-lactylaminc (N-alkyl derived from tallow amine, mixture of C₁₂-C₁₈ alkyls, average chain length 17.2 carbon atoms) in water, 9 ml paraffin oil was added. The mixture was thoroughly mixed for 30 seconds using an Ultra Turrax T 25 at 800 φm. The resulting product was a stable white emulsion, which remained stable for extended periods of time.

Example 13. Textile Washing Composition

The following components are combined (wt.%) to provide a textile washing composition:

Linear alkylbenzenesulphonate (C_ave 11.5) 7.5

N-Acetyl-N-hexadecyllactosylamine (invention) 4.0

Sodium soap (65% C₁₂_₁₈, 35% C₂₀_₂₂) 2.8

Zeolite A 25.0 Sodium carbonate 9.1

Sodium salt of a copolymer of acrylic and maleic acid (CP5) 4.0

Sodium silicate (SiO₂ : NaO₂ = 3.32 : 1) 2.6

Carboxymethylcellulose 1.0

EDTA 0.2 Optical brightener, stilbene based 0.2

Sodium sulphate, water, foam regulator 20.1

Enzyme prills protease (activity = 11 mAU/g) 0.5

Sodium perborate 20.0

TAED 3.0

Example 14. Textile Washing Composition

N-Carboxymethyl-N-hexadecyllactylamine 7.5

C₁₂_₁₈-Alcohols * EO₇ 4.0 Sodium soap (65% C₁₂_₁₈, 35% C₂₀_₂₂) 2.8

Zeolite A 25.0

Sodium carbonate 9.1

Sodium salt of a copolymer of acrylic and maleic acid (CP5) 4.0

Sodium silicate (SiO₂ : NaO₂ = 3.32 : 1) 2.6 Carboxymethylcellulose 1.0

EDTA 0.2

Optical brightener, stilbene based 0.2

Sodium sulphate, water, foam regulator 20.1

Enzyme prills protease (activity = 11 mAU/g) 0.5 Sodium perborate 20.0

TAED 3.0

Claims

1. A process for preparing surfactant derivatives of galacto-oligosaccharides, such as lactose, comprising preparing an N-alkyl-galactoglycitylamine having the formula Sar-NH-R¹, wherein Sar represents a reduced di- or oligosaccharide residue containing at least one galactose unit and R¹ represents a C₁-C_2Q alkyl group, by reacting the galacto-oligosaccharide with a C_j-C₂₀ alkylamine and reducing it, characterised by reductively animating the galacto-oligosaccharide with the alkylamine and hydrogen in a single step in the presence of a transition metal catalyst.

2. A process for preparing surfactant derivatives of galacto-oligosaccharides, such as lactose, comprising preparing an N-alkyl-galactoglycitylamine having the formula Sar-NH-R¹, wherein Sar represents a reduced di- or oligosaccharide residue containing at least one galactose unit and R¹ represents a C_j-C₂₀ alkyl group, by reacting the galacto-oligosaccharide with a C,-C₂₀ alkylamine and reducing it, characterised by aminating the galacto-oligosaccharide with the alkylamine by reactive processing without a solvent or with up to 4 weight parts of a solvent containing carbon, hydrogen and/or oxygen atoms only per weight part of oligo¬ saccharide, and reducing the N-alkyl-galactoglycosylaminc obtained.

3. A process for preparing surfactant derivatives of galacto-oligosaccharides, comprising preparing an N-acyl-galactoglycosylamine having the formula Sac-NR¹- CO-(NH)_m-R², wherein Sac represents a reducing di- or oligosaccharide residue containing at least one galactose unit, m is the number 0 or 1, R represents hydrogen or a _j^-C^ alkyl group and R² represents hydrogen or a C,-C₁₉ alkyl group, by aminating the galacto-oligosaccharide with ammonia or an amine having the formula R^NH-, and acylating the galactoglycosylamine thus obtained with an anhydride or acid halide having the formula R"-COX, wherein X represents a halogen atom or an acyloxy group, or by amidating the galacto-oligosaccharide with urea or an amide having the formula H₂N-CO-(NH)_m-R², characterised by performing the amination and/or acylation. or the amidation, by reactive processing without a solvent or with up to 4 weight parts of a solvent containing carbon, hydrogen and/or oxygen atoms only per weight part of galacto-oligosaccharide or galactoglycosylamine respectively, and, if desired, alkylating the product obtained with a compound having the formula R*X or R Y, wherein Y represents a leaving group.

4. A process for preparing surfactant derivatives of galacto-oligosaccharides, comprising preparing an N-acyl-galactoglycosylaminc having the formula Sac-NR¹- CO-R², wherein Sac represents a reducing di- or oligosaccharide residue containing at least one galactose unit, m is the number 0 or 1, R represents a CJ-C^_Q alkyl group and R² represents hydrogen or a C_j-C₁₉ alkyl group, by the galactoglycosylamine having the formula Sac-NHR with an anhydride or acid halide having the formula R"-COX, wherein X represents a halogen atom or an acyl- oxy group, characterised by performing the acylation in a solvent containing carbon, hydrogen and/or oxygen atoms only, preferably a lower alcohol.

5. A process for preparing surfactant derivatives of galacto-oligosaccharides, characterised by oxidising an optionally N-acylatcd N-alkyl-galactoglycosylamine or -galactoglycitylamine, to convert at least 2, in particular 4-100, of primary alcohol groups per 100 to a carboxyiic acid.

6. A process according to claim 5, wherein the amine is oxidised with a hypohalite, optionally in the presence of a di— tertiary alkyl nitroxyl compound.

7. A process according to claim 5, wherein the amine is oxidised with oxygen in the presence of a transition metal catalyst.

8. A process according to claim 5, wherein the amine is oxidised in the presence of a galacto-oxidase.

9. A process for preparing surfactant derivatives of galacto-oligosaccharides, characterised by converting an optionally N-acylatcd N-alkyl-galactoglycosylamine or -galactoglycitylamine with a haloalkyl-, hydroxyalkyl- or alkenyl-carboxylic acid, -phosphonic acid, -phosphate, -alkylphosphinatc. -phosphite, -sulphonic acid, -sulphate, or with a cyclic dicarboxylic anhydride, in particular with an α-halo- alkanoate.

10. N-Alkyl-galactoglycitylamine-acid having the formula Sar-NH-R¹, wherein Sar represents a reduced di- or oligosaccharide residue containing at least one galactose unit, in particular a lactyl group, and R¹ represents a CJ -C₂₀ alkyl group or a mixture of alkyl groups, wherein at least one oxygen or nitrogen atom is substituted with a group -(CH^COOH, -(CH₂)_nOPO(R )(OH), -(CH₂)_nOPO(OR⁴)(OH) or -(CH2)_nOSO₃H, wherein n = 1-4, in particular 1-2, or -(CH₂)_nPO(R⁴)(OH), -(CH₂)_nPO(OR⁴)(OH) or -(CH2)_nSO₃H, wherein n = 0-4, or -CO(CH₂)_nCOOH, wherein n = 1-3, or -CO- C₂H₃(SO₃H)-COOH, and wherein R⁴ represents a hydrogen atom or a hydrocarbon group having 1-7 carbon atoms.

11. N-Acyl-galactoglycosylamine having the formula Sac-NR^CO^NH^-R², wherein Sac represents a reducing di- or oligosaccharide residue containing at least one galactose unit, m represents the number 0 or 1,

R¹ represents a CJ -CJ_Q alkyl group or a mixture of alkyl groups and

R² represents hydrogen or a C_j-C₁₉ alkyl group, wherein one or more of the oxygen and nitrogen atoms may be substituted with a group -(CH₂)_nCOOH, -(CH₂)„OPO(R⁴)(OH), -(CH₂)_nOPO(OR⁴)(OH) or -(CH2)_nOSO₃H, wherein n = 1-4, in particular 1-2, or -(CH₂)_nPO(R⁴)(OH), -(CH₂)_nPO(OR⁴)(OH) or -(CH₂)_πSO₃H, wherein n = 0-4, or -O CH^COOH, wherein n = 1-3, or -CO-C₂H₃(SO₃H)-COOH, and wherein R⁴ represents a hydrogen atom or a hydrocarbon group having 1-7 carbon atoms; with the proviso that: if R² is methyl and m is 0, then the amine contains an acid group or R¹ contains at least 12 carbon atoms or a mixture of alkyl groups having an average of least 12 carbon atoms.

12. N-Acyl-galactoglycosylaminc according to claim 11, wherein R¹ represents an alkyl group having at least 12 carbon atoms or a mixture of alkyl groups having an average of least 12 carbon atoms.

13. N-Acyl-galactoglycitylamine having the formula Sar-NR¹-CO-(NH)_m-R², wherein

Sar represents a reduced di- or oligosaccharide residue containing at least one galactose unit, m represents the number 0 or 1,

R¹ represents hydrogen or a C,-C₂₀ alkyl group or a mixture of alkyl groups, and

R² represents hydrogen or a C_j-C^ alkyl group, wherein one or more of the oxygen and nitrogen atoms may be substituted with a group -(CH₂)_nCOOH, -(CH₂)_nOPO(R⁴)(OH), -(CH₂)_nOPO(OR⁴)(OH) or

-(CH₂)_nOSO₃H, wherein n = 1-4, in particular 1-2, or -(CH₂)_nPO(R⁴)(OH),

-(CH₂)_nPO(OR⁴)(OH) or -(CH₂)_nSO₃H, wherein n = 0-4, or

wherein n = 1-3, or -CO-C₂H₃(SO₃H)-COOH. and wherein R⁴ represents a hydrogen atom or a hydrocarbon group having 1-7 carbon atoms, with the proviso that if R¹ is nonyl, then the compound contains an acid group and/or m is 1 and/or R² is other than C₁₃-C₁₇ alkyl.

14. Oxidised galacto-oligosaccharide derivative having the formula Sax-NR^Z-R", wherein Sax represents a reducing or reduced di- or oligosaccharide residue containing at least one galactose unit, R¹ represents hydrogen or a C_j-C^ alkyl group or a mixture of alkyl groups,

R" represents hydrogen or a C_j-C^ alkyl group, and

Z represents a direct bond, a carbonyl group or a carbonylamino group, at least 2 per 100 primary alcohol groups in the Sax residue being converted to a carboxyiic acid group.

15. Use of an N-alkyl-galactosylglycitylaminc having the formula Sar-NH-R¹ wherein Sar represents a reduced di- or oligosaccharide residue containing at least one galactose unit, in particular a lactyl group, and R represents a mixture of alkyl groups having an average of at least 12 carbon atoms, as an emulsifier.

16. Use of a compound according to any one of claims 10-14 as an emulsifier.

17. Detergent, dispersant or emulsifying composition containing at least one compound according to any one of claims 10-14.

18. Composition according to claim 17, wherein said compound has the formula Sac-NR -CO-CH₃, wherein Sac represents a lactosyl group and R¹ represents a

C₁₂-C₁₈ alkyl group or a mixture thereof, or the formula

wherein Sar represents a lactyl group and R¹ represents a C₁₂-C₁₈ alkyl group or a mixture thereof.

19. Composition according to claim 17 or 18, which is a textile washing composition.