FR2569401A1 - New dimethylated derivatives of 3-nitro-4-aminoaniline, process for their preparation and their use in dyeing keratinous fibres - Google Patents

Abstract

Dimethylated derivatives of 3-nitro-4-aminoaniline of formula: in which CH3 is found in position 2 or 5 of the benzene nucleus and R1 and R2 denote, independently of each other, a hydrogen atom, a lower alkyl group, a lower mono- or polyhydroxyalkyl group or a lower aminoalkyl group whose amino group is optionally mono- or disubstituted by a lower alkyl radical or by a lower mono- or polyhydroxyalkyl radical, it being understood that one at least of the symbols R1 and R2 is different from hydrogen and that the two symbols R1 and R2 can only both be different from hydrogen when the movable CH3 radical is found in position 5, or the cosmetically acceptable salts of these compounds, as well as their process of preparation and their use in dyeing compositions, in particular for hair, both for direct dyeing and for dyeing oxidatively (by the oxidative route).

Description

 New dimethyl derivatives of 3-nitro-4-aminodiline, process for their preparation and their use in dyeing keratin fibers.

 The present invention relates to novel dimethyl derivatives of 3-nitro-4-aminyl aniline, to their process of preparation and to their use in dyeing keratinous fibers, and in particular human hair.

 It is well known that to give the hair a direct coloration or complementary reflections in the case of oxidation dyeing, it is possible to use nitro derivatives of the benzene series.

It has already been advocated the use of nitroparaphenylenediamines such as more particularly nitroparaphenylenediamine and 2-methyl-5-nitro paraphenylenediamine both in direct dyeing and oxidation dyeing.

 The perfect safety of these nitroparaphenylenediamines, however, has been questioned in recent years and it was sought thereby to replace these dyes in hair dye compositions.

 Furthermore, it has generally been found that the nitroparaphenylenediamines are poorly preserved in the reducing alkaline medium, especially comprising sodium bisulfite, which is usually used in oxidation dyeing compositions. Nitroparaphenylenediamines having a good preservation in a reducing alkaline medium have thus also been investigated.

 As a result of these investigations, the Applicant has discovered new dimethyl derivatives of 3-nitro-4-aminyl aniline having both a very low toxicity and a very good stability in solution, especially when they are used in a dyeing composition. oxidation in the presence of an alkaline agent and a reducing agent such as sodium bisulfite.

 The Applicant has also found that the hair dyes obtained using these new compounds have good stability to weather, light and washing.

 The subject of the present invention is therefore new dimethyl derivatives of 3-nitro-4-aminyl aniline as well as their process of preparation.

 The invention also relates to dye compositions for keratinous fibers, and in particular for human hair, containing these dimethyl derivatives of 3-nitro-4-aminodiline, dyeing compositions which can be used both for direct hair dyeing and for dyeing. by oxidation.

 Other objects and advantages of the present invention will become apparent on reading the description and examples which follow.

dans laquelle le radical CH3 à position variable peut se trouver en position 2 ou 5 du cycle benzénique et R1 et R2 désignent indépendamment l'un de l'autre un atome d'hydrogène, un groupe alkyle inférieur, monoou polyhydroxyalkyle inférieur ou aminoalkyle inférieur dont le groupement amino peut être éventuellement mono- ou disubstitué par un radical alkyle inférieur ou par un radical mono- ou polyhydroxyalkyle inférieur, étant entendu que l'un au moins des symboles R1 et R2 est différent de l'hydrogène et que les deux symboles R1 et R2 ne peuvent être simultanément différents de l'hydrogène que lorsque le radical CH3 mobile se trouve en position 5.The dimethyl derivatives of 3-nitroamino-4-aniline according to the invention correspond to the following formula (I)

in which the radical CH3 at variable position can be in position 2 or 5 of the benzene ring and R1 and R2 designate independently of each other a hydrogen atom, a lower alkyl, mono or lower polyhydroxyalkyl or aminoalkyl group of which the amino group may be optionally mono- or disubstituted with a lower alkyl radical or with a lower mono- or polyhydroxyalkyl radical, it being understood that at least one of the symbols R1 and R2 is different from hydrogen and that the two symbols R1 and R2 can not be simultaneously different from hydrogen only when the mobile CH3 radical is in position 5.

 These derivatives of formula (I) may also exist in the form of cosmetically acceptable salts.

 According to the invention, the lower alkyl group is an alkyl group containing 1 to 6 carbon atoms and preferably 1 to 4 carbon atoms.

 Particularly preferred radicals R 1 and R 2 according to the invention are methyl, ethyl, n-propyl, R-hydroxyethyl, hydroxypropyl, t-hydroxypropyl, ss, dihydroxypropyl, aminoethyl, aminopropyl and PN groups. N, N-diethylaminoethyl.

 Preferred compounds are those in which one of the radicals R 1 and R 2 denotes a hydrogen atom.

Particularly harmless compounds which are solid in washing and in light are the following compounds
4-amino-2,6-dimethyl-3-nitro-N-methylaniline
- 4-amino-5,6-dimethyl-3-nitro-N-9-hydroxyethylaniline
- 4-amino-5,6-dimethyl-3-nitro-N-dihydroxypropylaniline
4-amino-5,5-dimethyl-3-nitro-N-ss-aminoethylaniline.

 4-Amino-5,6-dimethyl-3-nitro-N - (- diethylaminoethyl) aniline.

 The compounds of formula (I) are prepared according to the following two procedures, depending on whether they are 2,6-dimethyl-3-nitro-paraphenylenediamine derivatives or 5-dimethyl-3-nitro-3-paraphenylened derivatives. iamine.

1 / Preparation of Secondary Amines Derived from 2,6-Dimethyl
nitro-3-para-phenylenediamine.

In this case it is necessary to conduct the alkylation of the amine
in position 1 on a precursor which is the p-toluene sulfonamide of
2,6-dimethyl-4-nitroaniline. As alkylating agents, it is possible
mention as non-limiting examples alkyl sulphates or
alkyl halides, substituted or unsubstituted. After desulfonation
by hydrolysis, this compound is reduced to 2,6-dimethyl paraphenylene
substituted diamine which is finally nitrated after acetylation of
the primary amine then hydrolysed.

The reaction scheme is as follows

<tb><SEP> NHSO2Ar <SEP> R <SEP>, / SO2Ar
<tb><SEP> CH <SEP> 3
<tb><SEP> CQ <SEP> + / <SEP> mlation <SEP> CH <SEP> CH3
<tb><SEP> Hydrolysis
<tb><SEP> NO2 <SEP> i 2
<tb><SEP> \ <SEP> /
<tb><SEP> 1) <SEP> CfI3ion
<tb><SEP> 1) <SEP> Reduction
<tb> CH3 <SEP> 1 <SEP> CH3 <SEP><dd> Hetylation <SEP> CH <SEP> CH3
<tb><SEP> CH3COC1
<tb><SEP> j <SEP> Oz
<tb><SEP> H / COCH3
<tb><SEP> 1) Nitration
<tb><SEP> 2) Hydrolysis
<tb><SEP> R <SEP> H
<tb><SEP> H
<tb> CH3 <SEP> CH3
<tb><SEP> o
<tb><SEP> NO2
<tb><SEP> NH2
<Tb>
Ar denotes the p-tolyl group and R1 having the meanings indicated in the formula (I), with the exception of hydrogen.

20 / Preparation of secondary and tertiary amines derived from
dimethyl-5,6-nitro-3-para-phenylenediamine.

In this case, the substitution of the amine in 1, which is more reactive, can
be conducted directly from the dimethyl-596 nitro-3 para
phenylenediamine by alkylation using an alkyl halide,
substituted or not, an epoxide or by opening an oxazoline
1.3 one-2 intermediate.

 The dyeing compositions in accordance with the invention contain, in a solvent medium, at least one compound corresponding to formula (I) and may be used for the direct dyeing of keratinous fibers or for the oxidation dyeing of these fibers, in which case the compounds of formula (I) confer complementary reflections on the basic coloring obtained by oxidative development of oxidation dye precursors.

 These compositions contain the compounds according to the invention in proportions of between 0.001 and 5% by weight and preferably between 0.05 and 2% by weight relative to the total weight of the composition.

 The solvent medium is preferably a cosmetic vehicle generally consisting of water, but organic solvents can also be added to the compositions in order to solubilize compounds which are not sufficiently soluble in water. Among these solvents, mention may be made of lower alkanols such as ethanol and isopropanol, aromatic alcohols such as benzyl alcohol, polyols such as glycerol, glycols or glycol ethers such as 2-butoxy ethanol or ethoxy. Ethanol, ethylene glycol, propylene glycol, diethylene glycol monoethyl ether and monomethyl ether, and similar products and mixtures thereof. These solvents are preferably present in proportions ranging from 1 to 75% by weight and in particular from 5 to 50% by weight relative to the total weight of the composition.

 These compositions may contain anionic, cationic, nonionic or amphoteric surfactants or mixtures thereof. These surface-active products are present in the compositions of the invention in proportions of between 0.5 and 55% by weight and preferably between 4 and 40% by weight relative to the total weight of the composition.

 The compositions may be thickened preferably with compounds selected from sodium alginate, gum arabic, cellulose derivatives such as methylcellulose, hydroxyethylcellulose, hydroxypropylmethylcellulose, carboxymethylcellulose and various polymers having the function of thickeners such as, more particularly, derivatives of acrylic acid. It is also possible to use inorganic thickeners such as bentonite. These thickening agents are preferably present in proportions of between 0.5 and 10% by weight and in particular between 0.5 and 3% by weight relative to the total weight of the composition.

 The compositions according to the invention may also contain various adjuvants usually used in hair dye compositions and in particular penetrating agents, dispersing agents, sequestering agents, film-forming agents, buffers and perfumes.

 These compositions can be in various forms such as liquid, cream, gel or any other form suitable for dyeing hair. They can also be packaged in aerosol flasks in the presence of a propellant.

 The pH of these dyeing compositions can be between 3 and 11.5, preferably between 5 and 11.5. It is adjusted to the desired value using an alkalinizing agent such as ammonia, sodium carbonate, potassium or ammonium, sodium or potassium hydroxides, alkanolamines such as mono, di- or triethanolamine, 2-amino-2-methylpropanol-1, 2-amino-2-methyl-1,3-propanediol, alkylamines such as ethylamine or triethylamine or with the aid of an acidifying agent such as phosphoric acid, hydrochloric acid, tartaric acid, acetic acid, lactic acid or citric acid.

When the compositions are intended to be used in a direct hair dyeing process, they may additionally contain compounds according to the invention the invention of other direct dyes such as azo or anthraquinone dyes, such as for example the tetra amino-1,4,5,8 anthraquinone, nitro dyes of the benzene series different from the compounds of formula (I) and more particularly the following compounds
2-methyl-6-nitroaniline,
2-methyl-4-aminophenophenol,
nitro-3-N'-hydroxyethylamino-4-N-methylaniline,
3-nitro N, N-hydroxyethyl-4-amino-N-methyl, N-hydroxyethyl-
aniline,
4-amino-3-nitro phenol,
3-amino-4-nitro phenol,
2-amino-3-nitro phenol,
N + -hydroxyethylamino-2-nitro-5-phenol,
N-hydroxyethylamino-2-nitroanisole,
2-methyl-5-nitro-N, N '- (- ss-hydroxyethyl) paraphenylenediamine, - 3-nitro N' - (β-hydroxyethyl) amino-4 N, N-bis (hydroxyethyl)
aniline,
N, O-3 N '- (- aminoethyl) amino-N, N-bis (ss-hydroxyethyl)
aniline,
4-amino-2-methyl-3-nitro-N-ss-hydroxyethylaniline,
4-N- (hydroxyethyl) amino-4-nitro-phenyl-hydroxyethyl
ether,
(N-methylamino-3-nitro-4) phenyl, p-hydroxyethyl ether.

2-isopropyl-6-nitroaniline,
used in free form or in the form of their salts.

 The concentrations of these direct dyes other than the dyes of formula (I) may be between 0.001 and 5% by weight relative to the total weight of the composition.

 These compositions, used in a direct dyeing process, are applied to the ericinic fibers for a laying time ranging from 5 to 50 minutes, and then the fibers are rinsed, optionally washed, rinsed again and dried.

 The compositions according to the invention may also be used in the form of hair styling lotions designed both to give the hair a slight color and to improve the holding of the setting. In this case, they are in the form of aqueous, alcoholic or aqueous-alcoholic solutions containing at least one cosmetic resin and their application is carried out on wet hair previously washed and rinsed which are optionally wound and dried.

 The cosmetic resins used in hair setting lotions may be in particular polyvinylpyrrolidone, crotonic acid-vinyl acetate copolymers, vinylpyrrolidone-vinyl acetate, maleic anhydride-butylvinyl ether, maleic anhydride-methylvinyl ether and any other cationic polymer. , anionic, nonionic or amphoteric usually used in this type of composition. These cosmetic resins are used in the compositions of the invention in a proportion of 0.5 to 4% by weight, and preferably 1 to 3% by weight, based on the total weight of the composition.

 When the compositions according to the invention are oxidation dyeing involving the development with an oxidant, the compounds of formula (I) according to the invention are mainly used to bring reflections to the final dyeing.

 These compositions then contain, in combination with at least one nitro dye of formula (I) and optionally other nitro dyes such as those mentioned above, dye precursors by oxidation.

 They may contain, for example, para-phenylenediamines such as: paraphenylenediamine, paryl olinediamine, 2-chloro-para-phenylenediamine, 2,6-dimethyl-para-phenylenediamine, 2,6-dimethyl-3-methoxy-paraphenylenediamine, N- (methoxyethyl) para-phenylenediamine, N, N - (- hydroxyethyl) paraphenylenediamine, N, N- (ethyl, carbamylmethyl) amino-4 aniline, and their salts.

 They may also contain para-aminophenols, for example para-aminophenol, N-methyl-para-aminophenol, chloro-2-amino-4-phenol, 3-chloro-4-aminophenol, 2-methyl-4-aminophenol, and their salts. .

 They may also contain ortho-aminophenol.

 They may also contain heterocyclic derivatives, for example: 2,5-diaminopyridine, 7-aminobenzomorpholine.

 The compositions according to the invention may contain, in combination with the oxidation dye precursors, couplers well known in the state of the art.

 As couplers, there may be mentioned in particular: meta-diphenols such as resorcinol, 2-methyl resorcinol, meta-aminophenols such as: meta-aminophenol, 2-methyl-5-aminophenol, 2-methyl-N-methylamino-5-phenol 2-methyl-N- (β-hydroxyethyl) amino-5-phenol, and their salts, meta-phenylenediamines such as: (2,4-diamino) phenoxyethanol, LN- (ss hydroxyethyl) amino-2-amino-4-phenoxyethanol, (2,4-diamino) phenyl, p-di-hydroxypropyl ether and their salts, metaacylaminophenols, metauridophenols, metacarbalcoxyaminophenols such as: methyl2 acetylamino-5-phenol, 2-methyl-ureido-5-phenol, methyl-2 carbethoxyamino-5-phenol.

 Finally, other couplers that may be used in the compositions of the invention may be mentioned: ## STR2 ## couplers having an active methylene group such as diketone compounds and pyrazolones and heterocyclic couplers such as 2,4-diaminopyridine, 6-hydroxybenzomorpholine, 6-aminobenzomorpholine and their salts.

 These compositions contain, in addition to the precursors of oxidation dyes, reducing agents such as, more particularly, sodium bisulfite, sodium sulphite, thioglycolic acid, thiolactic acid, mercapto-succinic acid and ascorbic acid. and their salts and hydroquinone. These reducing agents are present in proportions of between 0.05 and 3% by weight relative to the total weight of the composition.

 The oxidation dye precursors may be used, in the compositions of the invention, at concentrations of between 0.001 and 5% by weight and preferably between 0.03 and 2% by weight, based on the total weight of the composition. . The couplers may also be present in proportions of between 0.001 and 5% by weight, preferably between 0.015 and 2% by weight. The pH of these oxidation dyeing compositions is preferably between 7 and 11.5 and is adjusted with the aid of alkalinizing agents defined above.

 The Applicant has found that the compounds according to the invention are particularly stable in such compositions.

 The process for dyeing keratinous fibers, in particular human hair, using the revelation with an oxidant, consists in applying to the hair the dyeing composition comprising both a dye according to the invention and the dye precursors. The development of the coloration can then be carried out slowly in the presence of oxygen in the air, but preferably a chemical developer system is used which is most often chosen from hydrogen peroxide, urea peroxide and persalts. In particular, a solution of hydrogen peroxide at 20 volumes is used.

 Once the composition with the oxidizing agent has been applied to the keratinous fibers, it is allowed to set for 10 to 50 minutes, preferably 15 to 30 minutes, after which the keratinous fibers are rinsed, they are optionally washed with shampooing. they are rinsed again and dried.

 The examples which follow are intended to illustrate the invention without being limiting in nature.

PREPARATION EXAMPLE 1
Preparation of 4-amino-2,6-dimethyl-3-nitro-N-methylaniline

<tb><SEP> NHSO2 <SEP> OCH3 <SEP> CH <SEP> -N-SO <SEP> CH3
<tb> CH3 <SEP> ÈCH3 <SEP> C <SEP> step <SEP>CH3; E <SEP> 3
<tb><SEP> NO2 <SEP> Father <SEP> step <SEP> 2
<tb><SEP> 2nd <SEP> step
<tb><SEP> NHCH <SEP> NHCH
<tb> CH3 <SEP> CH3 <SEP> CH
<tb><SEP> 03CH23HC1 <SEP> CH3 <SEP> CH3
<tb> CH3 <SEP>;<SEP> 8 <SEP> 3rd <SEP> stage
<tb><SEP> H <SEP> NO2
<tb><SEP> j2 <SEP> 4th <SEP> step
<tb><SEP> NHCH3 <SEP> NHCH <SEP> NHCH
<tb> CH3 <SEP> CH3 <SEP> 5th <SEP> step <SEP> CH <SEP> X <SEP> CH3 <SEP> 6th <SEP> step <SEP> CH <SEP> CH
<tb><SEP> o <SEP> a <SEP> NO
<tb><SEP> -N02 <SEP>. <SEP> N02
<tb><SEP> NHCOCH3 <SEP> NHCOCH3 <SEP> NH2
<tb> 1st step
Preparation of N, N- (methyl, -toluenesulfonyl) amino-1-dimethyl-2,6-nitro benzene
0.053 mol (16.9 g) of p-toluenesulfonylamino-1-dimethyl-2,6-nitro-4-benzene were dissolved according to BM WEPSTER, Tr.Chemicals, Country
Bas, 73.809 [1954] in 120 ml of N / 2 sodium hydroxide. 0.06 moles (6 g) of dimethylsulfate are added little by little at 200 ° C. An additional hour is stirred.

 After dewatering and impingement in the water of the precipitate, a product is obtained which recrystallizes ethanol and melts at 128 ° C.

The analysis of the product obtained gives the following results:
Analysis% calculated% found
for C16B18N2 4
C 57.48 57.41
H, 5.43, 5.35
N 8.38 8.29
0 19.15 19.31
S 9.57 9.58 2nd stage
Preparation of 2,6-dimethyl-4-nitro-N-methylaniline
To a solution of 25 ml of 96% sulfuric acid and 2.5 ml of water heated to 600 ° C., 0.031 mole (10.4 g) of N, N- (methyltoluenesulphonyl) amino are slowly added. 2,6-dimethyl-4-nitro benzene. After 30 minutes of additional heating, the reaction medium is poured over 90 g of ice. The sulphate of the expected product is filtered off.

 The sulfate is suspended in water and then 20% ammonia is added; the expected product crystallizes. After recrystallization of the alcohol at 960, it melts at 990C.

The analysis of the product obtained gives the following results:
Analysis% calculated% found
for CgH12N202
C 59.98 60.06
H 6.71 6.75
N, 15.55, 15.50
0 17,76 17,77 3rd stage
Preparation of 4-amino-2,6-dimethyl-N-methylaniline dihydrochloride
A suspension of 15.5 g of zinc is refluxed. powder and 0.6 g of ammonium chloride. After removing the heating, 0.02 moles (3.6 g) of 2,6-dimethyl-4-nitro-N-methylaniline are added so as to maintain reflux. At the end of the addition, the reaction medium is filtered and boiled over a solution of 0.05 mol of hydrochloric acid in 14 ml of absolute ethanol. The dihydrochloride crystallizes from the filtrate. After recrystallization of an alcohol-water mixture, gives a white product - Molecular weight calculated for C9H16N2Cl2: 223 - Molecular weight found by potentiometric assay in water by
the soda: 220.

The analysis of the product obtained gives the following results:
Analysis% calculated% found
for C9H16N2C12
C 48.44 48.51
H 7.23 7.28
N 12.55 12.47
C1 31.78 31.77 4th stage
Preparation of N-methylamin4-dimethyl-3,5-acetanilide
To a solution of 0.17 moles (38 g) of 4-amino-2,6-dimethyl-N-methylaniline dihydrochloride in 170 ml of water is added at once 0.37 moles (46.6 g) of sulfite. of sodium dissolved in 170 ml of water and then dropwise for 30 minutes, 0.183 mol (19 g) of acetic anhydride, the temperature being maintained between 180C and 230C. After stirring for 2 hours, the mixture is filtered and the filtrate is neutralized with 20% aqueous ammonia. After wringing, washing with water and drying under vacuum, 0.12 mol (23.3 g) of the expected product is obtained; it melts at 820C.

Molecular mass calculated for CllB16N20: 192.3 Molecular weight found by potentiometric assay in the acid
acetic acid with perchloric acid: 195.

5th step
Preparation of N-methylamino-4-dimethyl-3,5-nitro-2-acetanilide
A solution of 5.6 ml of nitric acid (d = 1.50) in 20 ml of concentrated sulfuric acid containing 0.12 mol (23 g) of N-methylamino-4-dimethyl-3 is added little by little, Acetanilide in 120 ml of concentrated sulfuric acid while maintaining the temperature at OOC. After stirring for a further 30 minutes, the reaction medium is poured into 1 kg of ice. After neutralization with 20% ammonia, the expected product precipitates. Spent and recrystallized with alcohol at 960, it melts at 1330C.

- Molecular mass calculated for CllH15N303: 237 - Molecular weight found by potentiometric titration with acid
perchloric acid in acetic acid: 240.

The analysis of the product obtained gives the following results:
Analysis% calculated% found
for C11H15N303
C 55.68 55.55
H 6.37 6.40
N 17.71 17.80
0 20,23 20,00 6th stage
Preparation of 4-amino-2,6-dimethyl-3-nitro-N-methylaniline
0.11 mol (26.0 g) of N-methylamino-4-dimethyl-3,5-nitro-2-acetanilide is added to 65 ml of concentrated hydrochloric acid. The mixture is heated for 1 hour at 950 C. After cooling, the dihydrochloride of the expected product is filtered off.

 The dihydrochloride thus obtained is suspended in 400 ml of water. The medium is neutralized with ammonia at 20%, the expected product crystallizes. After drying and drying under vacuum in the presence of phosphorus pentoxide, it is recrystallized from a cyclohexanebenzene mixture; it melts at 57 "C.

- Molecular mass calculated for C9H13N302: 195 - Molecular weight found by potentiometric determination in the acid
acetic acid with perchloric acid: 195.

1ère étape Préparation de l'Camino-4 diméthyl-5,6 nitro-3 phénylJ carbamate de ss - chloréthyle
On dissout 0,05 mole (9,1 g) de diméthyl-5,6 nitro-3 paraphénylène diamine dans 40 ml de dioxane. On ajoute 0,055 mole (5,5g) de carbonate de calcium. On élève la température à 900C puis on introduit peu à peu sous agitation 0,053 mole (7,6 g) de chloroformiate de ss -chloréthyle. The analysis of the product obtained gives the following results:
Analysis% calculated% found
for CgH13N302
C 55.37 55.43
H 6.71 6.69
21.53 21.54
0 16.39 16.41
EXAMPLE OF PREPARATION 2
Preparation of 4-aminodimethyl-5,6-nitro-3-N-ss-hydroxyethylaniline

1st Step Preparation of 4-Camino-5,5-dimethyl-3-nitro phenyl-carbamate of ss-chloroethyl
0.05 moles (9.1 g) of 5,6-dimethyl-3-nitro-paraphenylene diamine are dissolved in 40 ml of dioxane. 0.055 mole (5.5 g) of calcium carbonate is added. The temperature is raised to 900 ° C. and then 0.053 mole (7.6 g) of chloramethyl chloroformate is gradually added with stirring.

The heating is continued 1 hour after the end of the addition. The reaction medium is poured into 200 g of ice water. The expected product precipitates.

After squeezing, reattachment in water and recrystallization of ethanol to 96, it melts at 1510C.

The analysis of the product obtained gives the following results:
Analysis% calculated z found
for C11H14N304Cl
C 45.92 46.10
H 4.90 4.89
N 14.61 14.50
0 22,24 22,25 2nd stage
Preparation of 4-Amino-5,6-dimethyl-3-nitro-N-hydroxyethylaniline
The suspension is suspended in 36 ml of methyl alcohol (0.0417 mol) (12 g) of 4-amino-dimethyl-5,6-nitro-phenyl] carbamate. A solution of 6.2 g of sodium hydroxide in 97% pellets in 15 ml of water is added little by little with stirring; the reaction mixture is refluxed with the alcohol. After heating for 2 hours, the reaction medium is poured into 200 g of ice water and acidified with acetic acid.

 After wringing, re-potting in water and recrystallization of ethyl acetate, the product melts at 166 ° C.

Molecular mass calculated for C10H15N3O3: 225.25 - Molecular weight found by potentiometric assay in the acid
acetic acid with perchloric acid: 223.

The analysis of the product obtained gives the following results:
Analysis% calculated% found
for CloH15N303
C 53.32 53.27
H 6.71 6.77
N 18.66 18.76
O 21.31 21.25 EXAMPLE OF PREPARATION 3
Preparation of 4-amino-5,6-dimethyl-3-nitro-N, 13-dihydroxypropylaniline

 0.05 mol (9 g) of 4-aminodimethyl-5,6-nitro-3-aniline and 0.1 mol (7.4 g) of glycidol in 18 ml of ethanol are heated on a steam bath while stirring with stirring. .

 After heating for 2 hours, the reaction medium is cooled, the precipitate is drained, washed with water, with alcohol and then dried. After dissolving in dimethylsulfoxide, then reprecipitation by adding water and drying, it melts at 181 ° C.

The analysis of the product obtained gives the following results:
Analysis% calculated% found
for CllH17N304
C 51.76 51.77
H, 6.67, 6.70
N 16.47 16.34
0 25.10 24.91
EXAMPLE OF PREPARATION 4
Preparation of 4-aminodimethyl-5,6-nitro-3 N-ss-aminoethylaniline

 Preheating at 80 ° C. with stirring a suspension of 0.5 mole (90 g) of dimethyl-5,6-nitro-3-paraphenylenediamine and 0.75 mole (75 g) of carbonate of lime in 350 ml of water and 150 ml of alcohol at 96. 1.2 moles (252 g) of bromoethylamine hydrobromide are added little by little with stirring. After refluxing for 1 hour 30 minutes, the reaction medium is cooled and 250 ml of concentrated hydrochloric acid are poured off, the precipitate thus obtained is drained, washed with water and then with acetone.After dissolution in 1 liter of ice water by adding ammonia, the salt of the expected product is obtained which, after alkalinization with 250 ml of 1N sodium hydroxide, gives 4-amino-5,6-dimethyl-3-nitro-N-Cl-aminoethylaniline. After washing with water, drying and recrystallization in ethyl alcohol, the product melts at 152 ° C.

Analysis% calculated% found
for C10H16N4O2
C 53.57 53.62
H 7.14 7.18
N 25.00 24.91
0 14.29 14.12
PREPARATION EXAMPLE 5 Preparation of 4-amino-5,6-dimethyl-3-nitro-N- (-diethylaminoethyl) aniline

 A mixture of 0.05 mol (9 g) of 5,6-dimethyl-3-nitro-paraphenylenediamine, 0.075 mol (7.5 g) of carbonate of lime and 0.1 mol (0.05 mol) is heated to 800 ° C. with stirring. 17.2 g) bromo-1 N, N-diethylamino-2 ethane in 36 ml of water and 18 ml of ethanol at 960.

After 45 minutes of heating, the reaction medium is filtered while hot and 25 ml of hydrochloric acid are added to the filtrate. The hydrochloride of the expected product precipitates. It is wrung and washed with acetone.

 The hydrochloride is dissolved in water, and by the addition of 1N sodium hydroxide in the presence of ice, an oil is obtained which precipitates. After wringing, washing with water and drying in the presence of phosphorus pentoxide under vacuum, the product obtained is recrystallized from ethanol at 960C.

 I1 melts at 980C.

The analysis of the product obtained gives the following results:
Z analysis calculated% found
for C14H24N402
C 60.00 59.96
H 8.57 8.46
N 20.00 20.02
0 11.43 11.67
EXAMPLE 1
Direct dyeing
The following dye composition is prepared: 4-amino-2,6-dimethyl-3-nitro-N-methylaniline 0.3 g 4-amino-2-methyl-3-nitro-N-hydroxyethylaniline 0.12 g Nitro-3N'-dihydrochloride 4-aminoethylamino-N, N- (1-hydroxyethyl) aniline 0.18 g - 2-amino-3-nitro-phenol 0.12 g - propylene glycol 10 g - hydroxyethylcellulose sold under the name
CELLOSIZE WP03 by UNION CARBIDE 2 g - cetyldimethylhydroxyethylammonium chloride 2 g
sold under the name CHIMEXON by the company CHIMEX - 5% Ammonia 4 ml - Water qs 100 g - pH 9.2
This mixture applied for 20 minutes at 280C on naturally white hair, 90% permed gives them, after shampooing and rinsing, a mahogany coloring.

EXAMPLE 2
Direct dyeing
The following dye composition is prepared - 4-amino-2,6-dimethyl-3-nitro-N-methylaniline 0.055 g - alcohol at 960 g - ALFOL C16 / 18 E 8 g
(cetylstearyl alcohol sold by the CONDEA Company) - Wax of E 0.5 g
(cetylstearyl sulphate of Na sold by HENKEL) - CEMULSOL B 1 g
(ethoxylated castor oil sold by RRONE-POULENC) - oleic diethanolamide 1.5 g - ammonia 5% lg - Water qs 100 g - pH 9.8
This mixture, applied for 30 minutes at 280.degree. C. on whitened hair to white, gives them, after shaking and rinsing, a light golden yellow coloring,
EXAMPLE 3
Direct dyeing
The following dye composition is prepared - 4-amino-5,5-dimethyl-3-nitrophen-0-hydroxyethylaniline 0.385 g - N-hydroxyethylamino-2-nitro-5-phenophenol 0.085 g - 3-nitro-N-hydroxyethylamino-4-N methyl, N-4 -hydro-
xyethylaniline 0.15 g - 2-butoxy ethanol 10 g - ALFOL C16 / 18 E 8 g
(cetylstearyl alcohol sold by the CONDEA Company) - Wax of E 0.5 g
(cetylstearyl sulphate of Na sold by HENKEL) - CEMULSOL B 1 g
(ethoxylated castor oil sold by RHONE-POULENC) - oleic diethanolamide 1.5 g - triethanolamine in 1% solution 2 ml - Water qs 100 g - pH 7.6
This mixture, applied for 25 minutes at 280 ° C. on bleached hair to white, gives them, after shapping and rinsing, a clear copper coloration.

EXAMPLE 4
Direct dyeing
The following dye composition is prepared - 4-amino-5,6-dimethyl-3-nitro-hydroxyethylaniline 2 g - 2-butoxy-methanol 25 g - CARBOPOL 934 from GOODRICH CHEMICAL CO 2 g
(polymer of acrylic acid PM: 2 to 3 million) - pure triethanolamine 4.5 g - Water qs 100 g - pH 7.6
This mixture applied for 15 minutes at 300C on naturally white hair at 90% gives them, after shampooing and rinsing, a beige-beige coloring.

EXAMPLE 5
Direct dyeing
The following dye mixture is prepared - 4-amino-5,6-dimethyl-3-nitro-N, gamma-dihydroxy-
pr opylaniline 0.25 g - 2-butoxyethanol 6g - LAURAMIDE - WITCO Company 1.5 g
(lauric acid monoethanolamide) - lauric acid 1 g - CELLOSIZE WP03 - Company UNION CARBIDE 5 g (hydroxyethylcellulose) - monoethanolamine 2 g - Water qs 100 g - pH 9.3
This mixture, applied for 20 minutes at 280C on hair discolored to white, gives them, after shampooing and rinsing, a 2.5 R 8/6 coloring.

EXAMPLE 6
Direct dyeing
The following dye mixture is prepared - 4-amino-5,6-dimethyl-3-nitro-3N-ss, -dihydroxypropyl
aniline 0.2 g - N '- (P-hydroxy-hydroxyethyl) -4-amino-3-nitro-N, N-bis- (p-hydroxyethyl) aniline 0.05 g - 4-amino-3-nitro-phenol 0, 1 g - butoxy-2 ethanol 10 g - ALFOL C 16/18 E - CONDEA company 8 g
(cetylstearyl alcohol) - Lanette E Wax - HENKEL Company 0.5 g
(cetylstearyl sodium sulfate) - CEMULSOL B - Company RHONE-POULENC 1 g
(ethoxylated castor oil) - oleic diethanolamide 1.5 g - Water qs 100 g - pH 7.2
This mixture, applied for 20 minutes at 300C on naturally 90% white hair, gives them, after shampooing and rinsing, a golden honey coloring.

EXAMPLE 7
Direct dyeing
The following dye mixture is prepared - 4-amino-5,6-dimethyl-3-nitro-N-ss-aminoethyl
aniline 0.5 g - 960 ethyl alcohol 10 g - COMPERLAN KD - HENKEL Company 2.2 g
(coconut fatty acid diethanolamide) - lauric acid 0.8 g - ethylene glycol ethyl monoether 2 g - monoethanolamine 6 g - water qs 100 g
pH 10
This mixture, applied for 20 minutes at 280C on hair, gives them, after shampooing and rinsing, a color
- on hair discolored with white 10 RP 5/8
- on naturally white hair at 90% 10 RP 3/10.

EXAMPLE 8
Direct dyeing
The following dye mixture is prepared - 4-amino-5,5-dimethyl-3-nitro-N-ss-aminoethylaniline 0.01 g - [N- (ss-hydroxyethyl) amino-4-nitro-3] phenyl-ss-hydro-
xylethyl ether 0.25 g - N '- (N-hydroxyethyl) amino-4-nitro-N, N-bis (ss-hydro)
xyethyl) aniline 0.20 g - 2-butoxy-ethanol 10 g - CEMULSOL NP 4 - Company RHONE-POULENC 12 g
(nonylphenol with 4 moles of ethylene oxide) - CEMULSOL NP 9 - Company PHONE POULENC 15 g
(nonylphenol with 9 moles of ethylene oxide) - oleic alcohol polyglycerolated with 2 moles of glycerol 1.5 g - oleic alcohol polyglycerolated with 4 moles of glycerol 1.5 g - lactic acid 0.5 g - Water qs 100 g - pH 5
This mixture, applied for 30 minutes at 300C on hair naturally white to 90%, gives them, after shampooing and rinsing, a rosy beige color.

EXAMPLE 9
Oxidation tincture
The following dye mixture is prepared - 4-amino-5,6-dimethyl-3-nitro-Np, t-dihydroxypropyl
aniline 0.1 g - para-phenylenediamine 0.05 g - para-aminophenol 0.27 g N-methylamino-4-phenol sulfate 0.12 g - 2,4-diamino-phenoxyethanol dihydrochloride 0.017 g - resorcinol 0.06 g - meta-aminophenol 0.055 g - isopropyl-2-nitro-6 aniline 0.04 g - CEMULSOL NP 4 21 g
(nonylphenol containing 4 moles of ethylene oxide sold by
RHONE POULENC) - CEMULSOL NP 9 24 g
(Nonylphenol containing 9 moles of ethylene oxide sold by
RHONE POULENC) - Oleic acid 4 g - butoxy-2 methanol 3 g - ethanol 96 10 g - MASQUOL DTPA 2.5 g
(sodium salt of diethylenetriamine pentacetic acid) - thioglycolic acid 0.6 g - ammonia at 22 Be 10 g - Water qs 100 g - pH 10.1
At the time of use, 100 g of hydrogen peroxide at 20 volumes are added.

 This mixture, applied 20 minutes at 300C on permed hair, gives them, after shampooing and rinsing, a light golden brown coloring.

EXAMPLE 10
Oxidation tincture
The following dye composition is prepared - 4-amino-5,5-dimethyl-3-nitro-N-ss-aminoethylaniline 0.15 g - (N-methylamino-3-nitro-4-nitro) phenyl, ss-hydroxyethyl ether 0.2 g - para-phenylenediamine , 08 g - para-aminophenol 0.1 g - resorcinol 0.05 g - meta-aminophenol 0.15 g - carboxymethylcellulose 2 g - ammonium lauryl sulphate 5 g - 2-butoxy-ethanol 8 g - propylene glycol 8 g - MASQUOL DTPA 2 g - acid thioglycolic 0.4 g - ammonium acetate 1 g - 22 Be ammonia 10 g - Water qs 100 g - pH 9.8
At the time of use, 100 g of hydrogen peroxide at 20 volumes are added.

 This mixture, applied to hair discolored for 25 minutes at 300C, gives them, after rinsing eting. a golden brown color.

EXAMPLE 11
Direct dyeing
The following dye mixture is prepared - 4-amino-5,6-dimethyl-3-nitro-N- (-dialylamino)
ethyl) aniline 0.25 g - alcohol 960 10 g - triethanolamine 1% by weight 3 g - CELLOSIZE WP 03 - Company UNION CARBIDE 2 g (hydroxyethylcellulose) - ammonium lauryl sulphate 5 g - Water qs 100 g - pH 8 37
This mixture, applied for 20 minutes at 280 ° C on discolored hair, gives them, after shampooing and rinsing, a coloration 9 R 7/5.

EXAMPLE 12
Oxidation tincture
The following dye mixture is prepared - 4-amino-5,6-dimethyl-3-nitro-N- (Pd ethylamine oethyl)
aniline 0.2 g - ortho-aminophenol 0.064 g - para-phenylenediamine 0.3 g - paraaminophenol 0.08 g - resorcinol 0.15 g - meta-aminophenol 0.08 g - CEMULSOL NP 4 (nonylphenol oxyethylenated to 4 moles
ethylene oxide sold by RRONE-POULENC) 12 g - CEMULSOL NP 9 (nonylphenol oxyethylenated to 9 moles
ethylene oxide sold by RSONE-POULENC) 15 g - oleic alcohol polyglycerolated with 2 moles of glycerol 1.8 g - oleic alcohol polyglycerolated with 4 moles of glycerol 1.5 g - propylene glycol 6 g - TRILON B (sodium salt) sodium of ethylenediamine
tetraacetic) 0.12 g - 220 Be ammonia 11 g - thioglycolic acid 0.6 g - Water qs 100 g - pH 10.5
At the time of use, an equal weight of hydrogen peroxide is added to 20 volumes.

 This mixture, applied 25 minutes at 280C on permed hair, gives them, after shampooing and rinsing, a medium brown coloring.

EXAMPLE 13
Direct dyeing
The following dye mixture is prepared - 4-amino-5,6-dimethyl-nitro-N- (p -dialylamino)
ethyl) aniline 0.05 g - 1,4-tetraamino, 5,8 anthraquinone 0,15-methyl-4-amino-4-nitro-5-phenol 0.1 g - 2-butoxy-ethanol 6g - LAURAMIDE - Company WITCO 1, 5 g
(lauric acid monoethanolamide) - lauric acid lg - CELLOSIZE WP 03 - Company UNION CARBIDE 5 g
(hydroxyethylcellulose) - monoethanolamine 2g - Water qs 100 g - pH 9.5
This mixture, applied for 30 minutes at 280C on hair naturally 90% white, gives them, after shampooing and rinsing, a sand coloring.

Claims (17)

 1. Dimethyl derivative of 3-nitro-4-aminoaniline, characterized in that it meets the following formula (I)

 in which the variable-position radical CH 3 is in the 2 or 5-position of the benzene ring and R 1 and R 2 denote, independently of one another, a hydrogen atom, a lower alkyl, mono- or polyhydroxy-lower alkyl group or lower aminoalkyl whose amino group is optionally mono- or disubstituted with a lower alkyl radical or with a lower mono- or polyhydroxyalkyl radical, it being understood that at least one of the symbols R1 and R2 is different from hydrogen, and that the two Symbols R1 and R2 can not be simultaneously different from hydrogen when the mobile CH3 radical is in the 5-position, and cosmetically acceptable salts of this compound.  2. Compound according to claim 1, characterized in that one of the radicals R1 and R2 denotes a hydrogen atom.  3. Compound according to claim 1 or 2, characterized in that it is chosen from the group comprising: 4-amino-2,6-dimethyl-3-nitro-N-methylaniline, 1-amino-4-imethyl-5, 6-nitro-N-β-hydroxyethylaniline, 4-amino-5,6-dimethyl-3-nitro-N-dihydroxypropylaniline, 4-amino-5,6-dimethyl-N-α-aminoethylaniline, 4-amino-5-amino-6-nitro-N- (ss-diethylaminoethyl) aniline.  4. Process for the preparation of a 2,6-dimethyl-3-nitro paraphenylene diamine of formula (I) according to claim 1, wherein the alkylation of a dimethyl-2,6-p-toluene sulfonamide is carried out. 4-nitro-aniline, then to the desulphonation of this compound by hydrolysis, a reduction is then carried out to obtain the 2,6-dimethyl-substituted paraphenylene diamine monosubstituted and after acetylation of the primary amine, the nitration is carried out and finally the hydrolysis of the acetyl group to obtain a 2,6-dimethyl-3-nitro paraphenylenediamine.  5. Process for the preparation of a dimethyl-5,6-nitro-3-paraphenylene diamine of formula (I) according to claim 1, characterized in that the alkylation of the 5,6-dimethyl-5-nitroquinone is directly carried out. 3 paraphenylenediamine using a substituted or unsubstituted alkyl halide, an epoxide or by opening an intermediate oxazoline-1,3-one-2.  6. Dye composition for keratin fibers, characterized in that it contains, in a solvent medium, at least one compound as defined in any one of claims 1 to 3.  7. Composition according to claim 6, intended for dyeing human hair, characterized in that it contains, in a cosmetically acceptable medium, at least one compound of formula (I) in the proportions of 0.001 to 5% by weight. and preferably between 0.05 and 2% by weight relative to the total weight of the composition.  8. Composition according to claim 6 or 7, characterized in that it has a pH of between 3 and 11.5.  9. Dyeing composition according to claim 6 or 7, characterized in that the solvents are chosen from water, lower alkanols, aromatic alcohols, polyols, and their ethers or mixtures thereof.  10. Composition according to claim 6 or 7, characterized in that it further contains cosmetic adjuvants chosen from anionic, cationic, nonionic or amphoteric surfactants or mixtures thereof, thickeners, dispersing agents, penetrating agents, sequestering agents, film-forming agents, buffers, perfumes, basifying or acidifying agents.  11. Composition according to claim 6 or 7, intended to be used for the direct dyeing of human hair, characterized in that it contains, in addition, other direct dyes chosen from azotic dyes, anthraquinone dyes and nitro derivatives. of the benzene series other than those of formula (I).  12. Composition according to claim 6 or 7, intended to be used as a setting lotion, characterized in that it is in the form of an aqueous solution, alcoholic or aqueous-alcoholic, containing at least one cosmetic resin.  13. The composition of claim 6 or 7, for use in the oxidation dyeing, characterized in that it further contains at least one dye precursor by oxidation.  14. Composition according to Claim 13, characterized in that it has a pH of between 7 and 11.5 and that it additionally contains a reducing agent.  15. A process for dyeing keratinous fibers, characterized in that a composition as defined in any one of claims 6 to 11 is applied to the fibers, allowed to set for 5 to 50 minutes, and rinsed, eventually washed, rinsed again and dried.  16. A process for dyeing keratinous fibers, characterized in that a composition as defined in claim 12 is applied to the washed and rinsed fibers, optionally wound up and dried.  17. A process for dyeing keratinous fibers, characterized in that a composition as defined in claims 13 or 14 is applied to the fibers, optionally supplemented with an oxidizing agent, it is left for 10 to 50 minutes, rinsed, washed optionally with shampoo, rinsed again and dried.