WO2011110627A1

WO2011110627A1 - New cationic 7-amino-1,2,3,4- tetrahydroquinolines, deying composition comprising a cationic 7-amino-1,2,3,4-tetrahydroquinoline, method and uses.

Info

Publication number: WO2011110627A1
Application number: PCT/EP2011/053611
Authority: WO
Inventors: Aziz Fadli
Original assignee: L'oreal
Priority date: 2010-03-12
Filing date: 2011-03-10
Publication date: 2011-09-15
Also published as: FR2957346B1; FR2957346A1

Abstract

The present invention relates to a family of cationic 7-amino- 1,2,3,4-tetrahydroquinolines of formula and to the processes for their synthesis. It also relates to a composition containing a cationic 7-amino- 1,2,3,4-tetrahydroquinoline, to the dyeing methods employing this composition, to the uses of said composition, more particularly for the dyeing of keratin fibres, and to the multiple-compartment devices or dyeing kits.

Description

NEW CATIONIC 7-AMINO- l ,2,3,4-TETRAHYDROQUINOLINES, DYEING COMPOSITION C OMPRISING A CATIONIC 7-AMINO- 1 ,2,3,4-TETRAHYDROQUINOLINE, METHODS AND USE S The present invention pertains to new cationic 7-amino- l , 2, 3 , 4- tetrahydroquinolines, to their use for the dyeing of keratin fibres, especially human keratin fibres such as the hair, to dyeing compositions comprising such cationic 7-amino- l , 2, 3 , 4-tetrahydro- quino lines, and to the methods and devices employing these cationic 7-amino- l ,2, 3 ,4-tetrahydroquinolines.

It is known practice to dye keratin fibres, and especially the human hair, with dyeing compositions containing oxidation dye precursors, generally called oxidation bases, such as ortho- or para- phenylenediamines, ortho- or para-aminopheno ls and heterocyclic compounds. These oxidation bases are colourless or weakly coloured compounds which, when combined with oxidizing products, are able to produce coloured compounds by a process of oxidative condensation.

It is also known that the shades obtained with these oxidation bases can be varied by combining them with couplers or coloration modifiers, the latter being selected more particularly from aromatic meta-diaminobenzenes, meta-aminophenols, meta-diphenols and certain heterocyclic compounds such as indole compounds .

The variety o f mo lecules used as oxidation bases and couplers allows a wide range of colours to be obtained.

The "permanent" coloration obtained by virtue of these oxidation dyes is required, moreover, to meet a certain number o f demands.

Thus it should have no toxico logical drawbacks, it should allow shades to be obtained in the desired intensity, and it should be highly resistant to external agents such as light, weathering, washing, perming treatments, perspiration and rubbing.

The dyes are also required to cover white hairs, and to be extremely unselective, in other words to produce the smallest possible differences in co loration along a single stretch of keratin fibre, which in general has a sensitivity (in other words, damage) which differs between its tip and its root.

Surprisingly and advantageously, the Applicant has now found a new family o f heterocyclic couplers composed of cationic 7-amino- 1 ,2,3 ,4-tetrahydroquinolines. These couplers allow new compositions to be obtained for the dyeing of keratin fibres that are capable o f producing co lorations in varied, strong and chromatic shades.

These compositions, moreover, are of low selectivity and are persistent : they effectively resist a variety o f the adverse effects to which the fibres may be subj ected.

These heterocyclic couplers exhibit, furthermore, a high so lubility, which allows a satisfactory uptake of the co lour.

The invention firstly provides a family of cationic 7-amino- 1 ,2,3 ,4-tetrahydroquinolines and the processes for their synthesis.

The invention further provides a composition comprising at least one cationic 7-amino- l ,2,3 ,4-tetrahydroquino line, the dyeing methods employing this composition, the uses of said composition according to the present invention for the dyeing of keratin fibres, especially human keratin fibres such as the hair, and, especially, the multi-compartment dyeing devices or kits .

Other features, aspects, obj ects and advantages of the present invention will emerge even more clearly from a reading o f the description and examples which follow.

The present invention relates to a cationic 7-amino- l , 2,3 ,4- tetrahydroquinoline o f general formula (I), its addition salts with an acid and its so lvates :

An^¬ il) in which the group NR'R" or the group NR carries the cationic charge, and in which:

R is a linear or branched, saturated C₁-C₂₀ alkyl radical which is optionally substituted or interrupted by a cationic radical, it being possible, furthermore, for R optionally to contain one or more groups selected from oxygen atoms, carbonyl groups (C=0), hydroxyl groups and groups NRi;

Ri is a hydrogen atom, a linear or branched C₁-C₄ alkyl radical or a linear or branched C₁-C₄ hydroxyalkyl radical, a benzyl radical or an acetyl radical;

R₂, R3, R4, R5, R₆ and R₇, independently of one another, are selected from the following: hydrogen atom, halogens selected from fluorine, chlorine and bromine, linear or branched C₁-C₄ alkyl radicals, and hydroxyalkyl (C₁-C₄), carboxyl (-COOH) and alkoxy(Ci-C₄)carbonyl radicals;

Ra, Rb and Rc, independently of one another, are selected from the following: hydrogen atom, halogens selected from fluorine, chlorine and bromine, and C₁-C₄ alkyl radicals;

R' and R", independently of one another, are selected from the following: hydrogen atom or C₁-C₄ alkyl radicals; when at least one of the radicals, R' or R", is a C₁-C₄ alkyl radical, then one of these alkyl radicals may be interrupted or substituted by a cationic radical.

A cationic radical present in the compound of formula (I) is understood preferably, in the context of the invention, to be any saturated or unsaturated, linear or branched or cyclic radical which contains a quaternary ammonium in the radical or as a substituent to the radical, this quaternary ammonium being of the type -N RdReRf, where Rd, Re and Rf are identical or different and represent a Ci-C₆ alkyl radical which may be substituted by a hydroxyl. Rd and Re may together form a 5- to 8-membered heterocycle, in which case Rf is a Ci-C₆ alkyl radical which may be substituted by a hydroxyl.

Examples of radicals -N RdReRf include tri(hydroxy)Ci-C₄- alkylammonium radicals such as, for example, trimethylammonium, triethylammonium, dimethylethylammonium, diethylmethylammonium, diisopropylmethylammonium, diethylpropylammonium, hydroxyethyl- diethylammonium, di-beta-hydroxyethylmethylammonium and tri-beta- hydroxyethylammonium, and also cationic heterocyclic radicals.

A "cationic heterocyclic radical" for the purposes of the present application is a heterocycle containing 5 to 8 members, with one of the members being a quaternary ammonium. Examples o f cationic heterocyclic radicals include imidazo liums, pyridiniums, piperaziniums, pyrrolidiniums, morpholiniums, pyrimidiniums, thiazo liums, benzimidazo liums, benzothiazo liums, oxazo liums, benzotriazoliums, pyrazoliums, triazoliums, benzoxazoliums and piperidiniums, which are optionally substituted by one or more identical or different radicals selected from linear or branched C ₁ -C₄ alkyl radicals and C ₁ -C₄ hydroxyalkyl radicals.

Preferably the group NR carries the cationic charge.

Preferably -R is a radical o f formula :

-C(0)-CH₂ (B-AK)p- CAT+

in which:

B represents an oxygen atom or a radical NRi in which Ri represents a hydrogen atom or a C ₁ -C₄ alkyl radical or a C ₁ -C₄ radical hydroxyalkyl radical; preferably B represents an oxygen atom or a radical NRi in which Ri represents a hydrogen atom or a C ₁ -C₄ alkyl radical;

AK represents a linear or branched, saturated C ₁ -C _{1 0} , preferably C i -C₆ , hydrocarbon chain which is optionally substituted by one or more hydroxyl radicals;

p = 0, 1 or 2;

when p is 2, the radicals B may be identical or different and the radicals AK may be identical or different;

CAT+ represents a cationic heterocyclic radical or a tri-C i - C₄- alkylammonium radical.

More preferably B represents an oxygen atom or an NH or NMe radical.

More preferably AK represents a saturated linear C ₁ -C₄ hydrocarbon chain. Preferably p = 0 or 1 .

Preferably CAT+ represents a cationic radical selected from the fo llowing :

- a cationic heterocyclic radical selected from imidazo liums, pyridiniums, pyrimidiniums, benzimidazoliums, thiazoliums, piperaziniums, pyrrolidiniums, morpholiniums and piperidiniums which are optionally substituted by one or more identical or different radicals selected from linear or branched C ₁ -C₄ alkyl radicals and C ₁ -C₄ hydroxyalkyl radicals;

- a tri- C i -C₄-alkylammonium radical selected from trimethyl- ammonium, triethylammonium, dimethylethylammonium, diethylmethylammonium, diisopropylmethylammonium and diethylpropylammonium.

More preferably CAT⁺ represents a cationic radical selected from the fo llowing :

- a cationic heterocyclic radical selected from imidazo liums, piperaziniums, pyrrolidiniums, morpholiniums and piperidiniums which are optionally substituted by one or more identical or different radicals selected from linear or branched C ₁ -C₄ alkyl radicals and C ₁ -C₄ hydroxyalkyl radicals;

- a tri-C i -C₄-alkylammonium radical selected from trimethyl- ammonium and triethylammonium.

Preferably R₂, R3 , P , R5 , R₆ and R₇, independently o f one another, are selected from hydrogen atom and C ₁ -C₄ alkyl radicals . More preferably R₂, R3 , R4 , R5 , R₆ and R₇ are hydrogen atoms.

Preferably Ra, Rb and Rc are hydrogen atoms.

The cationic 7-amino- l ,2,3 ,4-tetrahydroquinolines o f general formula (I) may be in free form or in the form o f salts, such as addition salts with an inorganic acid, selected preferably from hydrochlorides, hydrobromides, sulphates and phosphates, or with an organic acid, such as, for example, citrates, succinates, tartrates, lactates, tosylates, benzenesulphonates, acetates, para-toluene- sulphonates, formates and methanesulphonates.

The cationic 7-amino- l ,2,3 ,4-tetrahydroquinolines o f general formula (I) may also be in the form o f solvates, for example hydrate, or a so lvate o f a linear or branched alcoho l such as ethano l or isopropanol.

In the context of the invention, a derivative of formula (I) is understood to encompass all mesomeric or isomeric forms.

The electroneutrality o f the compounds of formula (I) is ensured by an anion or a mixture o f anions, labelled An-, which are organic or inorganic and are cosmetically acceptable.

An- represents an anion or a mixture of anions selected, for example, from a halide such as chloride, bromide, fluoride or iodide; a hydroxide; a sulphate; a hydrogensulphate; an alkylsulphate in which the linear or branched alkyl moiety is C i -C₆ , such as the methylsulphate or ethylsulphate ion; carbonates and hydrogen- carbonates; salts o f carboxylic acids, such as formate, acetate, citrate, tartrate and oxalate; alkylsulphonates for which the linear or branched alkyl moiety is C i -C₆ , such as the methylsulphonate ion; arylsulphonates for which the aryl moiety, preferably phenyl, is optionally substituted by one or more C ₁ - C4 alkyl radicals, such as, for example, 4-tolylsulphonate; and alkylsulphonates such as mesylate.

The cationic 7-amino- l ,2,3 ,4-tetrahydroquinolines o f general formula (I) are preferably selected from the fo llowing compounds :

l-(3-{[2-(7-amino-3,4- l-(2-{[2-(7-amino-3,4- dihydroquinolin-1 (2H)-yl)-2- dihydroquinolin-1 (2H)-yl)-2- oxo ethyl] amino} propyl)- 3 -methyl- oxoethyljamino} ethyl)-3- lH-imidazol-3-ium, An- methyl- 1 H-imidazol-3-ium,

An-

(compound 14)

(compound 13)

3-{[2-(7-amino-3,4- 4-(3-{[2-(7-amino-3,4- dihydroquinolin-1 (2H)-yl)-2- dihydroquinolin-1 (2H)-yl)-2- oxo ethyl] amino} -Ν,Ν,Ν- oxo ethyl] amino} propyl) -4- trimethylpropan- 1 -ammonium, methylmorpholin-4-ium, An- An-

(compound 15) (compound 16)

l-(3-{[2-(7-amino-3,4- l-(3-{[2-(7-amino-3,4- dihydroquinolin-1 (2H)-yl)-2- dihydroquinolin-1 (2H)-yl)-2- oxo ethyl] amino} propyl)- 1 - oxo ethyl] amino} propyl)- 1 - methylpyrrolidinium, An- methylpiperidinium, An-

(compound 17) (compound 18)

ere An- has the same signification as before

The cationic 7-amino-l,2,3,4-tetrahydroquinolines of general formula (I) according to the present application may be prepared by various synthesis routes.

The present application further relates to a process for synthesis of a cationic 7-amino-l,2,3,4-tetrahydroquinoline of general formula (I) in which:

- the radicals R' and R" represent hydrogen atoms and

- R corresponds to -C(0)-CH₂ (B-AK)p-CAT⁺,

in which:

B represents an oxygen atom or a radical NRi in which Ri represents a hydrogen atom or a C1-C4 alkyl radical or a C1-C4 hydroxyalkyl radical; AK represents a saturated, linear or branched Ci-Cio hydrocarbon chain which is optionally substituted by one or more hydroxyl radicals;

p = 0, 1 or 2;

CAT+ represents a cationic heterocyclic radical or a tri-Ci-C₄- alkylammonium radical;

- the definitions of the radicals R₂, R₃, R₄, Rs, R₆, R7, Ra, Rb and Rc are as given for the definition of the cationic 7-amino-l, 2,3,4- tetrahydroquinoline of general formula (I),

from a 7-nitro-l,2,3, -tetrahydroquinoline of formula (II):

(Π) said process comprising at least the following steps, in this order:

• acylation of the NH group in position 1, using a haloacetyl halide,

• if p = 1 or 2, replacing the halogen in the group carried by the N atom in position 1 by a group HB-AK-X where X is a halogen,

• replacing the halogen in the group carried by the N atom in position 1 by the cationic group CAT⁺ or by an aminoalcoholate or an amine, to give a precursor of the cationic group,

• cationization of the precursor, if the product obtained in the preceding step is not cationic,

• reduction of the nitro group.

This process is summarized in the schemes on Fig. 1, when p =0, and on Fig. 2, when p = 1 or 2.

In these schemes, B, AK, CAT and p are as defined before, with CAT corresponding to CAT⁺, and with the electroneutrality being ensured by An^" as defined before.

PRECAT : a radical which can be cationized to a cationic radical CAT, in other words CAT⁺.

The first step is an acylation reaction o f the 7-nitro- l , 2,3 ,4- tetrahydroquinoline ( 1 ) under conventional conditions, for example by reaction with a halo acetyl halide in a polar so lvent o f alcoho l, alkyl acetate, THF, dioxane or acetic acid type, for example, at a temperature o f between 0°C and 100°C . Depending on the nature o f the haloacetyl, the compounds (2) or (9) are obtained.

Depending on the nature o f the amine employed subsequently, either the nitro compounds (3) or (6) are obtained directly or it is necessary to replace the halogen in the compound (2) by an amine or an aminoalcoho late, to give the derivatives (4) or (7), which are subsequently cationized with at least one equivalent o f alkyl halide or methyl sulphate or alkyl carbonate or hydroxyalkyl halide, in a so lvent such as THF or acetonitrile or dioxane or ethyl acetate, or in a chlorinated so lvent such as dichloromethane or 1 ,2-dichloroethane, for 15 minutes to 24 hours at a temperature ranging from 15 °C to the reflux temperature of the so lvent, to give the cationic nitro compounds (5) or (8).

The reduction o f the nitro group in the compounds (3), (6), (5) or (8) to give the compounds o f the invention (I) is performed under conventional conditions, for example by carrying out a hydrogenation reaction by heterogeneous catalysis in the presence o f Pd/C, Pd(II)/C , Ni/Ra, etc. , or else by carrying out a reduction reaction with a metal, for example zinc, iron, tin, etc. (see Advanced Organic Chemistry, 3rd edition, J. March, 1985 , Wiley Interscience, and Reduction in Organic Chemistry, M . Hudlicky, 1983 , Ellis Horwood Series Chemical Science) .

The present application also relates to the uses of a cationic 7- amino- l ,2,3 ,4-tetrahydroquinoline o f general formula (I), and more particularly to the use thereo f as a coupler for the dyeing o f keratin fibres, more particularly human keratin fibres such as the hair.

The present application also relates to a cosmetic dyeing composition, more particularly for dyeing keratin fibres such as the hair, comprising, in a medium appropriate for dyeing, at least one cationic 7-amino- l ,2,3 ,4-tetrahydroquinoline o f general formula (I) .

Preferably the concentration o f the cationic 7-amino- l , 2,3 ,4- tetrahydroquinoline o f general formula (I) is between 0.0001 % and 20%), preferably between 0.005 %> to 6%> by weight, relative to the total weight of the composition.

The medium appropriate for dyeing generally comprises water or a mixture of water and at least one organic solvent such as, for example, branched or unbranched C 1 - C 4 lower alcoho ls, such as ethano l and isopropanol; po lyo ls and polyo l ethers, such as 2- butoxyethanol, propylene glyco l, propylene glycol monomethyl ether, diethylene glycol monoethyl ether and monomethyl ether, and glycerol, and also aromatic alcoho ls such as benzyl alcoho l or phenoxyethano l, and mixtures thereof.

Advantageously the cosmetic composition comprises at least one cosmetic adjuvant selected from the group consisting o f antioxidants, penetrants, sequestrants, perfumes, buffers, dispersants, surfactants, conditioning agents, film formers, polymers, ceramides, preservatives, pearlizing or opacifying agents, vitamins or provitamins .

The above adjuvants are generally present in an amount, for each o f them, o f between 0.01 % and 20% by weight, relative to the weight of the composition.

The composition further comprises at least one oxidation base . These bases may more particularly be selected from para- phenylenediamines, bis-phenylalkylenediamines, para-aminophenols, ortho-aminopheno ls and heterocyclic bases, and their addition salts.

The para-phenylenediamines include more particulalry, for example, para-phenylenediamine, para-toluenediamine, 2-chloro-para- phenylenediamine, 2,3 -dimethyl-para-phenylenediamine, 2, 6 -dimethyl- para-phenylenediamine, 2,6-diethyl-para-phenylenediamine,

2.5 - dimethyl-para-phenylenediamine, N, N- dimethyl-par a-phenylene- diamine, Ν,Ν-diethyl-para-phenylenediamine, N,N-dipropyl-para- phenylenediamine, 4 - amino -N,N- diet hy 1-3 -met hylaniline, N,N-bis( - hydroxy ethyl) -para-phenylenediamine, 4 -N,N-bis( - hydroxy ethyl) - amino-2-methylaniline, 4 -N,N-bis( - hydroxy ethyl) amino -2- chloro- aniline, 2- -hydroxyethyl-para-phenylenediamine, 2-fluoro-para- phenylenediamine, 2 -isopropyl-para-phenylene diamine,

Ν-(β -hydroxy propyl) -para-phenylenediamine, 2-hydroxymethyl-para- phenylenediamine, N, N- dimethyl- 3 -methyl-para-phenylene diamine, N,N-(ethyl- -hydroxyethyl)-para-phenylenediamine, Ν-(β,γ- dihydroxypropyl) -para-phenylenediamine, N- (4 '-amino phenyl) -para- phenylenediamine, N-phenyl-para-phenylenediamine, 2- -hydroxy- ethyloxy-para-phenylenediamine, 2- -acetylaminoethyloxy-para- phenylenediamine, N-( -methoxyethyl)-para-phenylenediamine, 4-aminophenylpyrrolidine, 2-thienyl-para-phenylenediamine, 2-β- hydroxyethylamino-5 -aminotoluene, 3 -hydroxy- 1 -(4'-aminophenyl)- pyrrolidine, 6-(4-aminophenylamino)hexan- 1 -o l and their addition salts with an acid.

Among the abovementioned para-phenylenediamines, particular preference is given to para-phenylenediamine, para-toluenediamine, 2 -isopropyl-para-phenylene diamine, 2 -β-hydroxy ethyl-par a- phenylenediamine, 2 -β-hydroxyethyloxy-para-phenylene diamine,

2.6- dimethyl-para-phenylenediamine, 2,6-diethyl-para- phenylenediamine, 2,3-dimethyl-para-phenylenediamine, N,N-bis( - hydroxy ethyl) -para-phenylenediamine, 2-chloro -para- phenylenediamine, 2- -acetylaminoethyloxy-para-phenylenediamine, 2- [ {2- [(4-aminophenyl)amino] ethyl} (2 - hy droxy ethyl) amino ] ethanol, N-(4-amino-3 -methylphenyl)-N- [3 -( l H-imidazo l- 1 -yl)propyl] amine, N-(4-aminophenyl)-N- [3 -( l H-imidazo l- l -yl)propyl] amine and their addition salts with an acid.

The bisphenylalkylenediamines include, for example, Ν,Ν'- bis( -hydroxyethyl)-N,N'-bis(4'-aminophenyl)- l ,3-diaminopropanol, N,N'-bis-( -hydroxyethyl)-N,N'-bis(4'-aminophenyl)ethylenediamine, N,N'-bis(4-aminophenyl)tetramethylene diamine, N,N'-bis(P-hydroxy- ethyl)-N,N'-bis(4-aminophenyl)tetramethylene diamine, N,N'-bis(4- methylaminophenyl)tetramethylene diamine, N, N'-bis( ethyl) -

N,N'-bis(4'-amino-3'-methylphenyl)ethylenediamine, 1 ,8-bis(2,5- diaminophenoxy)-3,6-dioxaoctane, and their addition salts with an acid.

The para-aminophenols include, for example, para- aminophenol, 4-amino-3-methylphenol, 4-amino-3-fluorophenol, 4-amino-2-chlorophenol, 4-amino-3-chlorophenol, 4-amino-3- hydroxymethylphenol, 4-amino-2-methylphenol, 4-amino-2- hydroxymethylphenol, 4-amino-2-methoxymethylphenol, 4-amino-2- aminomethylphenol, 4-amino-2-( -hydroxyethylaminomethyl)phenol, 4-amino-2-fluorophenol, 4-amino-2,6-dichlorophenol, 4-amino-6- [((5 '-amino -2 '-hydroxy- 3 '-methyl)phenyl)methyl]-2-methylphenol, bis[(5 '-amino-2 '-hydroxy)phenylmethane and their addition salts with an acid.

The ortho-aminophenols include, for example, 2-aminophenol, 2-amino-5-methylphenol, 2-amino-6-methylphenol, 5-acetamido-2- aminophenol, and their addition salts with an acid.

Among the heterocyclic bases that may be mentioned, for example, are pyridine derivatives, pyrimidine derivatives and pyrazole derivatives.

The pyridine derivatives include the compounds described, for example, in patents GB 1 026 978 and GB 1 153 196, such as 2,5-diaminopyridine, 2-(4-methoxyphenyl)amino-3-aminopyridine, 3,4-diaminopyridine, and their addition salts with an acid. Other pyridine bases useful in the present invention are the oxidation bases described by patent applications EP 1792903 and EP 1792606, and their addition salts with an acid.

Other pyridine oxidation bases useful in the present invention are the 3-aminopyrazolo[ 1 ,5-a]pyridine oxidation bases or their addition salts, described, for example, in patent application FR 2801308. Examples include pyrazolo[ 1 ,5-a]pyridin-3-ylamine; 2-acetylaminopyrazolo[ 1 ,5-a]pyridin-3-ylamine; 2-morpholin-4-yl- pyrazolo[ 1 ,5-a]pyridin-3-ylamine; 3-aminopyrazolo[ 1 ,5-a]pyridin-2- carboxylic acid; 2-methoxypyrazolo[l,5-a]pyridine-3-ylamino; (3-aminopyrazolo[ 1 ,5-a]pyridine-7-yl)methanol; 2-(3-aminopyrazolo- [1 ,5-a]pyridine-5-yl)ethanol; 2-(3-aminopyrazolo[ 1 ,5-a]pyridine-7-yl)- ethanol; (3-aminopyrazolo[ 1 ,5-a]pyridine-2-yl)methanol; 3,6-diamino- pyrazolo[ 1 ,5-a]pyridine; 3,4-diaminopyrazolo[l ,5-a]pyridine; pyrazolo[ 1 ,5-a]pyridine-3,7-diamine; 7-morpholin-4-ylpyrazolo- [1 ,5-a]pyridin-3-ylamine; pyrazolo[l ,5 -a]pyridine-3,5 -diamine;

5-morpholin-4-ylpyrazolo[ 1 ,5-a]pyridin-3-ylamine; 2- [(3 -amino - pyrazolo[ 1 ,5-a]pyridin-5-yl)-(2-hydroxyethyl)amino]ethanol; 2-[(3- aminopyrazolo[ 1 , 5 -a]pyridin-7-yl)-(2-hydroxyethyl)amino] ethanol;

3- aminopyrazolo[ 1 ,5-a]pyridine-5-ol; 3-aminopyrazolo[l ,5-a]pyridine-

4- ol; 3-aminopyrazolo[ 1 ,5-a]pyridine-6-ol; 3-aminopyrazolo- [1 ,5-a]pyridine-7-ol;

and their addition salts with an acid.

The pyrimidine derivatives include the compounds described, for example, in the patents DE 2359399; JP 88-169571; JP 05-63124; EP 0770375 or patent application WO 96/15765, such as 2,4,5,6- tetraamino pyrimidine, 4-hydroxy-2,5,6-triaminopyrimidine, 2-hydroxy- 4,5,6-triaminopyrimidine, 2,4-dihydroxy-5,6-diaminopyrimidine, 2,5,6-triaminopyrimidine and their addition salts and their tautomeric forms, when a tautomeric equilibrium exists.

The pyrazolopyrimidine derivatives include the compounds described in patent applications EP 0847271, EP 0926149 and EP 1147109, and their addition salts.

The pyrazole derivatives include the compounds described in the patents DE 3843892, DE 4133957 and patent applications WO 94/08969, WO 94/08970, FR-A-2 733 749 and DE 195 43 988, such as 4,5-diamino-l-methylpyrazole, 4,5-diamino- 1 -(β- hydroxyethyl)pyrazole, 3,4-diaminopyrazole, 4,5-diamino-l-(4'- chlorobenzyl)pyrazole, 4,5-diamino - 1 ,3 -dimethylpyrazole,

4,5-diamino -3 -methyl- 1 -phenylpyrazole, 4,5-diamino - 1 -methyl- 3- phenylpyrazole, 4 -amino - 1 ,3-dimethyl-5-hydrazinopyrazole, 1-benzyl- 4,5-diamino-3-methylpyrazole, 4,5-diamino-3-tert-butyl- 1 -methyl- pyrazole, 4,5-diamino- 1 -tert-butyl-3-methylpyrazole, 4,5-diamino- 1- (β-hydroxy ethyl) -3 -methy lpyrazole, 4,5-diamino - 1 -ethy 1-3 -methy 1- pyrazole, 4,5-diamino - 1 - ethy 1-3 -(4'-methoxyphenyl)pyrazole,

4,5-diamino - 1 -ethy 1-3 -hydro xymethylpyrazole, 4,5-diamino -3- hydro xymethyl- 1 -methy lpyrazole, 4,5-diamino- 3 -hydro xymethyl- 1 - isopropylpyrazole, 4,5-diamino-3-methyl-l-isopropylpyrazole, 4- amino-5-(2'-aminoethyl)amino- 1 , 3 -dimethy lpyrazole, 3,4,5-triamino- pyrazole, 1 -methyl-3,4,5-triaminopyrazole, 3,5-diamino- 1 -methy 1-4 - methylaminopyrazole, 3, 5 -diamino-4-( -hydroxy ethyl) amino - 1 -methy 1- pyrazole, and their addition salts.

Oxidation bases further include the diamino-N,N-dihydro- pyrazolone derivatives of formula (IV) or one of their addition salts or solvates:

(IV)

in which:

Ri, R₂, R₃ and R₄ are identical or different and represent:

- a linear or branched Ci-C₆ alkyl radical which is optionally substituted by one or more radicals selected from the group consisting of a radical OR₅, a radical NR₆R7, a carboxyl radical, a sulphonyl radical, a carboxamido radical CONR₆R7, a sulphonamido radical S0₂NR₆R7, a heteroaryl, an aryl optionally substituted by a (Ci-C₄)alkyl group, a hydroxyl, a Ci-C₂ alkoxy, an amino, a (di)alkyl(Ci-C₂)amino;

- an aryl radical optionally substituted by one or more of (Ci-C₄)alkyl, hydroxyl, Ci-C₂ alkoxy, amino, (di)alkyl(Ci-C₂)amino;

- a 5- or 6-membered heteroaryl radical which is optionally substituted by one or more radicals selected from (Ci-C₄)alkyl and (Ci-C₂)alkoxy;

R₃ and R₄ may also represent a hydrogen atom; R₅, R₆ and R₇ are identical or different and represent a hydrogen atom; a linear or branched C₁-C₄ alkyl radical which is optionally substituted by one or more radicals selected from the group consisting of a hydroxyl, a C₁-C₂ alkoxy, a carboxamido CONR₈R , a sulphonyl SO₂R₈, an aryl optionally substituted by a (Ci-C₄)alkyl, a hydroxyl, a C₁-C₂ alkoxy, an amino, a (di)alkyl(Ci-C₂)amino; an aryl optionally substituted by a (Ci-C₄)alkyl, a hydroxyl, a C₁-C₂ alkoxy, an amino, a (di)alkyl(Ci-C₂)amino;

R₆ and R₇ are identical or different and may also represent a carboxamido radical CONR8R or a sulphonyl SO2R8;

R₈ and R₉ are identical or different and represent a hydrogen atom or a linear or branched C₁-C₄ alkyl radical which is optionally substituted by one or more of hydroxyl, C₁-C₂ alkoxy;

Ri and R₂, on the one hand, and R3 and R₄, on the other hand, may form, with the nitrogen atoms to which they are attached, a saturated or unsaturated heterocycle containing 5 to 7 members which is optionally substituted by one or more radicals selected from the group consisting of halogen atoms, amino, (di)alkyl(Ci-C₄)amino, hydroxyl, carboxyl, carboxamido and (Ci-C₂)alkoxy radicals, C₁-C₄ alkyl radicals optionally substituted by one or more hydroxyl, amino, (di)alkylamino, alkoxy, carboxyl or sulphonyl radicals;

R₃ and R₄ may also form, together with the nitrogen atom to which they are attached, a 5- or 7-membered heterocycle in which the carbon atoms may be replaced by an optionally substituted nitrogen or oxygen atom.

These diamino-N,N-dihydropyrazolone derivatives are described more particularly in application FR 2866338, and one particularly preferred derivative is 2,3-diamino-6,7-dihydro-lH,5H- pyrazolo[ 1 ,2-a]pyrazol- 1 -one dimethanesulphonate.

Oxidation bases further include the diamino-N,N-dihydro- pyrazolone derivatives of formula (I) or one of their addition salts or solvates:

in which:

• Z represents independently:

- a single covalent bond or

- a divalent radical selected from

- an oxygen atom,

- a radical -NR₆-, where R₆ represents a hydrogen atom or a Ci-C₆ alkyl radical, or R₆ with R₃, together with the nitrogen atom to which they are attached, form a 5- to 8-membered heterocycle which is unsubstituted or substituted, saturated or unsaturated, aromatic or non- aromatic, and optionally contains one or more other heteroatoms or groups selected from N, O, S, S0₂, -CO-, it being possible for the heterocycle to be cationic and/or to be substituted by a cationic radical,

- a radical -N⁺R₇R8- where R₇ and Rs independently represent an alkyl radical; the alkyl radical may be substituted by an OH or an -Oalkyl,

• R₃ represents:

- a hydrogen

- a Ci-Cio alkyl radical which is optionally substituted, it being possible for the alkyl radical to be interrupted by a heteroatom or a group selected from O, N, Si, S, SO and S0₂,

- a Ci-Cio alkyl radical which is substituted and/or interrupted by a cationic radical,

- a halogen,

- an S0₃H radical,

a 5- to 8-membered ring which is substituted or unsubstituted, saturated or unsaturated or aromatic and optionally contains one or more heteroatoms or groups selected from N, O, S, S0₂, -CO, it being possible for the ring to be cationic and/or to be substituted by a cationic radical, • Ri and R₂ are identical or different and represent:

- a linear or branched Ci-C₆ alkyl radical which is optionally substituted by one or more radicals selected from a radical OR₅, a radical NR₉R₁₀, a carboxyl radical, a sulphonyl radical, a carboxamido radical CONR9R10; a sulphonamido radical

a heteroaryl, an aryl which is optionally substituted by a (Ci-C₄)alkyl, hydroxyl, Ci-C₂ alkoxy, amino or (di)alkyl(Ci-C₂)amino group;

- an aryl radical which is optionally substituted by one or more of (Ci-C₄)alkyl, hydroxyl, Ci-C₂ alkoxy, amino and (di)alkyl(Ci-C₂)- amino;

- a 5- or 6-membered heteroaryl radical which is optionally substituted by one or more radicals selected from (Ci-C₄)alkyl which is monosubstituted or polysubstituted by an OH or an -Oalkyl, (Ci-C₂)alkoxy;

Ri and R₂ may form, with the nitrogen atoms to which they are attached, a saturated or unsaturated heterocycle containing 5 to 7 members which is optionally substituted by one or more radicals selected from the group consisting of halogen atoms, amino, (di)alkyl(Ci-C₄)amino, hydroxyl, carboxyl, carboxamido and (Ci-C₂)alkoxy radicals, C₁-C4 alkyl radicals which are optionally substituted by one or more hydroxyl, amino, (di)alkylamino, alkoxy, carboxyl or sulphonyl radicals,

An- represents an anion or a group of anions which ensures the electroneutrality of the compounds of formula (I),

with the proviso that at least one of the groups Z and R3 represents a cationic radical.

These diamino-N,N-dihydropyrazolone derivatives are described in patent application FR 2927078.

In general the concentration of the oxidation base or bases is between 0.0001% and 20%, preferably between 0.005% to 6% by weight, relative to the total weight of the composition.

The composition according to the invention preferably comprises at least one additional oxidation coupler other than the cationic 7-amino-l,2,3,4-tetrahydroquinolines of general formula (I). These oxidation couplers include more particularly meta- phenylenediamines, meta-aminopheno ls, meta-diphenols, naphthalenic couplers and heterocyclic couplers, and their addition salts .

Examples include 2-methyl-5 -aminophenol, 5 -N-(B- hydroxy ethyl) amino -2 -met hylpheno l, 6-chloro-2-methyl-5 -amino- pheno l, 3 -aminophenol, 1 ,3 -dihydroxybenzene (or resorcinol),

1 .3 - dihydroxy-2-methylbenzene, 4-chloro- 1 ,3 -dihydroxybenzene,

2.4- diamino- 1 - (B -hydroxy ethyloxy)benzene, 2-amino-4-(B-hydroxy- ethylamino)- 1 -methoxybenzene, 1 ,3 -diaminobenzene, 1 ,3 -bis-(2,4- diaminophenoxy)propane, 3 -ureidoaniline, 3 -ureido- 1 -dimethyl- aminobenzene, sesamo l, l -B-hydroxyethylamino-3 ,4-methylene- dioxybenzene, OC-naphtho l, 2-methyl- 1 -naphtho l, 6-hydroxyindole, 4-hydroxyindo le, 4-hydroxy-N-methylindo le, 2-amino-3 -hydroxy- pyridine, 6-hydroxybenzomorpholine, 3 ,5 -diamino-2,6- dimethoxypyridine, 1 -N- (B -hydroxy ethyl)amino- 3 ,4 -methylene- dioxybenzene, 2,6-bis(B-hydroxyethylamino)toluene and their addition salts.

In general the concentration o f the oxidation coupler or couplers other than the cationic 7-amino - l ,2,3 ,4-tetrahydroquinolines according to the present invention is between 0.0001 % to 20%>, preferably between 0.005 %> to 6%> by weight, relative to the total weight of the composition.

Generally speaking, the addition salts with an acid that can be used for the oxidation bases and the couplers are selected more particularly from hydrochlorides, hydrobromides, sulphates, citrates, succinates, tartrates, lactates, tosylates, benzenesulphonates, phosphates and acetates.

The dyeing composition in accordance with the invention may further comprise one or more direct dyes, which may more particularly be selected from neutral, acidic or cationic nitro dyes of the benzene series, neutral, acidic or cationic direct azo dyes, neutral, acidic or cationic direct quinone, and especially anthraquinone, dyes, direct azine dyes, direct methine, azomethine, triarylmethane and indoamine dyes and direct natural dyes. The composition according to the invention preferably comprises at least one dye selected from cationic direct dyes and natural direct dyes .

The cationic direct dyes which can be used according to the invention include the cationic direct azo dyes described in patent applications WO 95/ 15 144, WO-95/01772 and EP-714954.

These compounds include especially the following dyes :

- 1 ,3 -dimethyl-2- [ [4-(dimethylamino)phenyl] azo] - 1 H- imidazo lium chloride,

- 1 ,3 -dimethyl-2- [(4-aminophenyl)azo] - l H-imidazo lium chloride,

- 1 -methyl-4- [(methylphenylhydrazono)methyl]pyridinium methylsulphate.

The direct natural dyes which can be used according to the invention include lawsone, juglone, alizarin, purpurin, carminic acid, kermesic acid, purpurogallin, protocatechaldehyde, indigo, isatin, curcumin, spinulo sin and apigenidin. It is also possible to use extracts or decoctions containing these natural dyes and especially henna- based poultices or extracts .

The direct dye or dyes represents or represent, preferably, from 0.001 % to 20% by weight, approximately, of the total weight of the composition, and more preferably approximately from 0.005 % to 10% by weight.

The person skilled in the art will o f course ensure that the adjuvant or adjuvants, additional oxidation dye precursors and direct dyes are selected such that the advantageous properties intrinsically attached to the oxidation dyeing composition in accordance with the invention are not, or not substantially, adversely affected by the intended addition or additions.

The pH of the dyeing composition in accordance with the invention is generally between approximately 3 and 12, and preferably between approximately 5 and 1 1 . It may be adjusted to the desired value by means of acidifying or alkalifying agents which are typically used in the dyeing of keratin fibres or else using conventional buffer systems. The acidifying agents include, for example, organic or inorganic acids other than dicarboxylic acids, such as hydro chloric acid, ortho -phosphoric acid, sulphuric acid, carboxylic acids such as acetic acid, tartaric acid, citric acid, lactic acid, and sulphonic acids .

The alkalifying agents include, for example, aqueous ammonia, alkali metal carbonates , alkanolamines such as mono - , di- and triethanolamines and their derivatives, sodium hydro xide or potassium hydro xide, and the compounds o f formula :

in which W is a propylene residue which is optionally sub stituted by a hydro xyl group or a C ₁ -C₄ alkyl radical; R_a, R_b, R_c and R_d are identical or different and represent a hydrogen atom or a C ₁ -C₄ alkyl or C ₁ -C₄ hydroxyalkyl radical .

The cosmetic composition according to the invention may b e present in a variety o f forms, such as in the form o f liquids, creams, gels, or any other form which is appropriate for carrying out dyeing o f keratin fibres , and more particularly o f human hair.

The present application relates to a method o f dyeing keratin fibres, in which the composition according to the present invention as defined above is applied to the keratin fibres for a time sufficient to develop the desired co loration in the presence o f an oxidizing agent, the oxidizing agent being applied before, simultaneously with or after the composition.

The colour may be revealed at acidic, neutral or alkaline pH , and the oxidizing agent may be added to the composition o f the invention right at the time of use, or it may be employed on the basis o f an oxidizing composition which comprises it and which is applied simultaneously with or sequentially to the composition o f the invention.

In one particular embo diment the composition according to the present invention is mixed, preferably at the time o f use, into a composition containing, in a medium appropriate for dyeing, at least one oxidizing agent, this oxidizing agent being present in an amount sufficient to develop a coloration.

In this particular embodiment, a ready-to-use composition is available which is a mixture of a composition according to the invention with at least one oxidizing agent. The resulting mixture is subsequently applied to the keratin fibres for a time sufficient for the desired coloration to develop . After a contact time o f approximately 3 to 50 minutes, preferably approximately 5 to 30 minutes, the keratin fibres are rinsed, washed with shampoo, rinsed again and then dried.

The oxidizing agents conventionally used for the oxidation dyeing o f keratin fibres are, for example, hydrogen peroxide, urea peroxide, alkali metal bromates, persalts such as perborates and persulphates, peracids and oxidase enzymes, including peroxydases, 2-electron oxidoreductases, such as uricases, and 4-electron oxygenases, such as laccases . Hydrogen peroxide is particularly preferred.

The oxidizing composition may further comprise various adjuvants which are used conventionally in compositions for dyeing hair, and are as defined above.

The pH o f the oxidizing composition comprising the oxidizing agent is such that, after mixture with the dyeing composition, the pH of the resultant composition applied to the keratin fibres varies from preferably between 3 and 12 approximately, and more preferably between 5 and 1 1 . It may be adjusted to the desired value by means o f acidifying or alkalifying agents which are commonly used in dyeing keratin fibres and are as defined above.

The ready-to-use composition which is ultimately applied to the keratin fibres may be present in a variety o f forms, such as in the form o f liquids, creams or gels or any other form appropriate for carrying out dyeing o f keratin fibres, and more particularly of human hair.

The present application further provides a method of dyeing keratin fibres, in which the ready-to-use composition is applied to said fibres for a time sufficient to develop the desired coloration. The time sufficient to develop the desired coloration corresponds in general to a contact time of approximately 3 to 50 minutes, preferably approximately 5 to 30 minutes .

The invention further provides a multi-compartment device or dyeing kit in which a first compartment contains the dyeing composition defined above and a second compartment contains an oxidizing composition. This device may be equipped with a means allowing the desired mixture to be delivered to the hair, such as the devices described in patent FR-2 586 913 in the name o f the Applicant.

Using this device, it is possible to dye the keratin fibres on the basis of a method which comprises mixing a dyeing composition in accordance with the invention with an oxidizing agent as defined above, and applying the resulting mixture to the keratin fibres for a time sufficient to develop the desired coloration.

The examp les which fo llow serve to illustrate the invention, but without having any limiting character.

EXAMPLES

Synthesis examples :

Examp le 1 : l - [2-(7-amino-3 ,4-dihydroquinolin- l (2H)-yl)-2- oxo ethyl] -3 -methyl- l H-imidazo l-3 -ium chloride

❖ Synthesis o f l -(chloroacetyl)-7-nitro- l , 2,3 ,4- tetrahydroquinoline ( 10)

1 10

1 .78 g of 7-nitro- l ,2,3 ,4-tetrahydroquinoline (0.01 mol) are dissolved in 15 ml of ethyl acetate. The solution is poured into a mixture of 15 ml of ethyl acetate (EA) and 0.80 ml of chloroacetyl chloride. A white precipitate forms immediately, and stirring is continued at 30°C for 2 hours (the reaction is monitored by TLC (90/10 ethyl acetate/heptane)). After 2 hours, since the reaction is incomplete, 0.2 equivalent of chloroacetyl chloride is added and the temperature is raised to 60°C; the solid formed undergoes dissolution. When the reaction has finished, the mixture is cooled and the solvent is evaporated. 2.46 g are recovered of a beige product which corresponds to the expected compound with a yield of 97%.

1H NMR (400 MHz, DMSO-d6, delta ppm) : 1 .90 (m, 2H, CH2), 2.85 (t, 2H, CH2), 4.75 (s, 2H, CH2), 7.50 (d, 1 H, CH), 7.90 (d, 1 H, CH).

❖ Synthesis of l -[2-(7-nitro-3 ,4-dihydroquinolin- l (2H)- y 1) -2 -oxo ethyl] -3 -methyl- l H-imidazol-3-ium chloride

N Cf

2 g of product 10, l -(chloroacetyl)-7-nitro- l ,2,3 ,4-tetra- hydroquinoline (0.008 mol), are dissolved in 30 ml of ethyl acetate under hot conditions (40°C) and 0.8 ml of N-methylimidazole is added. The mixture is taken to reflux, and the formation of a white precipitate is observed. The reaction is monitored by TLC (90/10 ethyl acetate/heptane) and by mass. When the starting product is no longer detected by mass spectrometry, the precipitate formed is filtered off hot on a frit, and then washed with ethyl acetate and isopropyl ether, before being dried under reduced pressure.

This gives 2.43 g of a pale yellow solid which corresponds to the expected compound with a yield of 92%.

1H NMR (400 MHz, MeOD, delta ppm): 2.81 (s, 3H, CH3), 4.85 (s, 2H, NH2), 7.38 (td, 1H, H2, 4J=2.2Hz, 3J=7.09Hz and 3J=8.31Hz), 7.75 (m, 2H, H3 and H4), 9.44 (dt, 1H, HI, 4J=2.2Hz, 3J=6.84Hz, and 5J=0.97Hz ).

Synthesis of l-[2-(7-amino-3,4-dihydroquinol 1 (2H) -yl) -2 -oxo ethyl] -3 -methyl- lH-imidazo 1-3- ium

A 100 ml, three-necked, round-bottomed flask equipped with a condenser and a thermometer is charged with 30 ml of ethanol and 2 g (0.006 mol) of reagent 11 (l-[2-(7-nitro-3,4-dihydroquinolin-l(2H)- yl)-2-oxoethyl]-3-methyl- lH-imidazol-3-ium chloride). The mixture is heated to reflux. Following complete dissolution of the reagent, 1 g of Pd/C catalyst (at 5%, 50% moisture content) and 3 ml of cyclohexene are added. The reaction is monitored by TLC for 2 hours 30 minutes.

The catalyst is subsequently removed by filtration on a frit with Celite, and the filtrate is concentrated under reduced pressure. A yellow solid is formed which is taken up in hot ethanol, after which the ethanol is evaporated to give an oil. The oil in turn is taken up in a few ml of isopropanol on a sieve, and the solvent is evaporated. This gives a solid in the form of a "meringue" of 1.20 g, which corresponds to the expected product with a yield of 75%.

Analysis by mass spectrometry and NMR spectroscopy confirm the expected compound.

Mass spectrometry: The quasi-molecular ions [M+H] + , [M+Na] + , [M+Na+CH30H]+, [M-H]- of the expected molecule are principally detected. 1H NMR (400 MHz, MeOD, delta ppm): 2.81 (s, 3H, CH3), 4.85

(s, 2H, NH2), 7.38 (td, 1H, H2, 4J=2.2Hz, 3J=7.09Hz and 3J=8.31Hz), 7.75 (m, 2H, H3 and H4), 9.44 (dt, 1H, HI, 4J=2.2Hz, 3J=6.84Hz, and 5J=0.97Hz). Example 2: 4-[2-(7-amino-3,4-dihydroquinolin-l(2H)-yl)-2- oxoethyl]- 1 , 1 -dimethylpiperazin- 1 -ium chloride hydrochloride (16)

5 g of product 10, l-(chloroacetyl)-7-nitro-l, 2,3,4- tetrahydroquinoline (0.008 mol), are dissolved in 50 ml of ethyl acetate under hot conditions and then 4.4 ml of methylpiperazine are introduced. The mixture is heated at reflux and the formation of a brown precipitate is observed. The reaction is monitored by TLC (90/10 ethyl acetate/heptane) and mass spectrometry. When the starting product is no longer detected by TLC, the insoluble material is filtered off hot on a frit. The solid is then taken up in ethanol, after which the ethanol is evaporated to dryness to give a brown oil, which leads to a solid following addition of water. The solid is filtered off on a frit and then dried under reduced pressure to give 4.46 g of yellow solid, corresponding to the expected compound, with a yield of 70%.

1H NMR (400 MHz, MeOD, delta ppm): 2.81 (s, 3H, CH3), 4.85 (s, 2H, NH2), 7.38 (td, 1H, H2, 4J=2.2Hz, 3J=7.09Hz and 3J=8.31Hz), 7.75 (m, 2H, H3 and H4), 9.44 (dt, 1H, HI, 4J=2.2Hz, 3J=6.84Hz, and 5J=0.97Hz).

❖ Synthesis of l,l-dimethyl-4-[2-(7-nitro-3,4-dihydro- quinolin- 1 (2H)-yl)-2-oxoethyl]piperazin- 1 -ium methyl

A 100 ml three-necked flask equipped with a condenser and a thermometer is charged with 2.5 g (0.008 mol) of compound 13 (l-[(4- methylpiperazin- 1 -yl) acetyl]- 7 -nitro- 1 ,2,3,4-tetrahydroquinoline) and 40 ml of THF. The mixture is heterogeneous. The mixture is cooled in a bath of cold water. Dimethyl sulphate is added dropwise and a yellow precipitate appears. The mixture is stirred overnight at ambient temperature.

The precipitate is filtered off on a glass frit, washed with THF and isopropyl ether, and then dried in a desiccator, to give 3.18 g of yellow solid, corresponding to the expected compound, with a yield of 91%.

❖ Synthesis of 4-[2-(7-amino-3,4-dihydroquinolin- 1 (2H)-yl)-2-oxoethyl]- 1 , 1 -dimethylpiperazin- 1 -ium chloride hydrochloride (16)

A 100 ml three-necked round-bottomed flask equipped with a condenser and a thermometer is charged with 30 ml of ethanol and 3 g (0.006 mol) of reagent 15. The mixture is heated to reflux. Following complete dissolution of the reagent, 1 g of Pd/C catalyst (5%, 50% moisture content) and 3 ml of cyclohexene are added. The reaction is monitored by mass spectrometry for 2 hours 30 minutes.

The catalyst is then removed by filtration on a frit on a bed of Celite, and the filtrate is concentrated under reduced pressure. A pasty yellow solid is formed, which is taken up in isopropanol containing a little hydrochloric acid. Following removal of the isopropanol under reduced pressure, a solid is isolated, which is taken up with isopropyl ether and then filtered and dried to give 2.1 g of beige solid, corresponding to the expected compound in the form of the hydrochloride, with a yield of 93%.

1H NMR (400 MHz, MeOD, delta ppm): 2.81 (s, 3H, CH3), 4.85 (s, 2H, NH2), 7.38 (td, 1H, H2, 4J=2.2Hz, 3J=7.09Hz and

3J=8.31Hz), 7.75 (m, 2H, H3 and H4), 9.44 (dt, 1H, HI, 4J=2.2Hz, 3J=6.84Hz, and 5J=0.97Hz ). DYEING EXAMPLES

The following dyeing compositions are prepared:

Example 3 4

2-[(3-Aminopyrazolo[l ,5-a]pyridin-

10^"3 mol 10^"3 mol 2-yl)oxy] ethanol hydrochloride

l-[2-(7-Amino-3,4- dihydroquinolin- 1 (2H)-yl)-2- oxo ethyl] -3 -methyl- lH-imidazol- 10^"3 mol

3-ium chloride

(compound 1)

4-[2-(7-Amino-3,4- dihydroquinolin-l(2H)-yl)-2- oxoethyl]- 1 , 1 -dimethylpiperazin- - 10^"3 mol 1-ium chloride hydrochloride

(compound 2)

Dyeing medium (1) (1)

Demineralized water qs 100 g 100 g

Intense chromatic

Shade observed Pearly pink violet red Example 5 6

4-(3-Aminopyrazolo[l ,5-a]pyridin- 2-yl)- 1 , 1 -dimethylpi erazin- 1 -ium 10^"3 mol 10^"3 mol chloride hydrochloride

l-[2-(7-Amino-3,4- dihydroquinolin- 1 (2H)-yl)-2- oxo ethyl] -3 -methyl- lH-imidazol- 10^"3 mol - 3-ium chloride

(compound 1)

(compound 2)

Dyeing medium (1) (1)

Demineralized water qs 100 g 100 g

Intense chromatic

Shade observed Yellow-green turquoise blue

Example 7 8

1 - {2-[(3-Aminopyrazolo[ 1 ,5-a]pyridin- 2-yl)amino] ethyl} -3 -methyl- 1 H- imidazol-3-ium chloride 10^"3 mol 10^"3 mol hydrochloride l-[2-(7-Amino-3,4- dihydroquinolin- 1 (2H)-yl)-2- oxo ethyl] -3 -methyl- lH-imidazol- 10^"3 mol - 3-ium chloride

(Example 1 )

(compound 2)

Dyeing medium (1) (1)

Demineralized water qs 100 g 100 g

Intense, very

Intense turquoise

Shade observed chromatic

blue blue Example 9 10

4-Aminophenylamine dihydrochloride 10^"J mol 10^"J mol l-[2-(7-Amino-3,4-dihydroquinolin- l(2H)-yl)-2-oxoethyl]-3-methyl-lH-

10^"3 mol - imidazol-3-ium chloride

(compound 1)

4-[2-(7-amino-3,4-dihydroquinolin- l(2H)-yl)-2-oxoethyl]-l,l- dimethylpiperazin- 1 -ium chloride - 10^"3 mol hydrochloride

(compound 2)

Dyeing medium (1) (1)

Demineralized water qs 100 g 100 g

Shade observed Bluish gray Matt grey

Example 11 12-[ {2-[(4-Aminophenyl)amino]ethyl} (2- hydroxy ethyl) amino Jethanol 10-3 mol 10-3 mol hydrochloride

l-[2-(7-Amino-3,4-dihydroquinolin- l(2H)-yl)-2-oxoethyl]-3-methyl-lH-

10-3 mol - imidazol-3-ium chloride

(compound 1)

4-[2-(7-Amino-3,4-dihydroquinolin- l(2H)-yl)-2-oxoethyl]-l,l- dimethylpiperazin- 1 -ium chloride - 10-3 mol hydrochloride

(compound 2)

Dyeing medium (1) (1)

Demineralized water qs 100 g 100 g

Shade observed Grey Matt gray Example 13 14

4-Aminophenol 10^"J mol 10^"J mol l-[2-(7-Amino-3,4-dihydroquinolin- l(2H)-yl)-2-oxoethyl]-3-methyl-lH-

10^"3 mol - imidazol-3-ium chloride

(compound 1)

4-[2-(7-Amino-3,4-dihydroquinolin- l(2H)-yl)-2-oxoethyl]-l,l- dimethylpiperazin- 1 -ium chloride - 10^"3 mol

hydrochloride

(compound 2)

Dyeing medium (1) (1)

Demineralized water qs 100 g 100 g

Shade observed Pearly rose Pearly

(*): Dyeing medium (1) pH 9.5

96° ethyl alcohol

35% aqueous sodium metabisulphite solution

40%) aqueous solution of the pentasodium salt

diethylenetriaminepentaacetic acid

C8-C10 alkyl polyglucoside in aqueous solution at 60%>

Benzyl alcohol

Polyethylene glycol containing 8 ethylene oxide units

NH4C1

Aqueous ammonia containing 20%> NH3

At the time of use, each composition is mixed with an equal weight of 20-volumes hydrogen peroxide (6% by weight). This gives a final pH of 9.5.

Each mixture obtained is applied to swatches of grey hair containing 90% white hairs. After 30 minutes' contact, the swatches are rinsed, washed with a standard shampoo, rinsed again and then dried, giving the shades reported.

Claims

1. Cationic 7-amino-l,2,3,4-tetrahydroquinoline

rmula (I), its addition salts with an acid and its solvates

An^¬ il)

in which the group NR'R" or the group NR carries the cationic charge, and in which:

^■ R is a linear or branched, saturated C1-C20 alkyl radical which is optionally substituted or interrupted by a cationic radical, it being possible, furthermore, for R optionally to contain one or more groups selected from oxygen atoms, carbonyl groups (C=0), hydroxyl groups and groups NRi;

^■ Ri is a hydrogen atom, a linear or branched C1-C4 alkyl radical or a linear or branched C1-C4 hydroxyalkyl radical, a benzyl radical or an acetyl radical;

^■ R₂, R3, R4, R5, R₆ and R₇, independently of one another, are selected from the following: hydrogen atom, halogens selected from fluorine, chlorine and bromine, linear or branched C1-C4 alkyl radicals, and hydroxyalkyl (C1-C4), carboxyl (-COOH) and alkoxy(Ci-C4)carbonyl radicals;

^■ Ra, Rb and Rc, independently of one another, are selected from the following: hydrogen atom, halogens selected from fluorine, chlorine and bromine, and C1-C4 alkyl radicals;

■ R' and R", independently of one another, are selected from the following: hydrogen atom or C1-C4 alkyl radicals; when at least one of the radicals, R' or R", is a C₁-C₄ alkyl radical, then one of these alkyl radicals may be interrupted or substituted by a cationic radical,

An- is an anion or a mixture of anions which are organic or inorganic and are cosmetically acceptable.

2. Cationic 7-amino-l,2,3,4-tetrahydroquinoline according to Claim 1, in which the group -NR carries the cationic charge.

3. Cationic 7-amino-l,2,3,4-tetrahydroquinoline according to Claim 1 or 2, in which the cationic radical is selected from trimethylammonium, triethylammonium, dimethylethylammonium, diethylmethylammonium, diisopropylmethylammonium, diethylpropyl- ammonium, hydroxyethyldiethylammonium, di-beta-hydroxyethyl- methylammonium and tri-beta-hydroxyethylammonium radicals and also imidazoliums, pyridiniums, piperaziniums, pyrrolidiniums, morpholiniums, pyrimidiniums, thiazoliums, benzimidazoliums, benzothiazoliums, oxazoliums, benzotriazoliums, pyrazoliums, triazoliums, benzoxazoliums and piperidiniums which are optionally substituted by one or more identical or different radicals selected from linear or branched C₁-C₄ alkyl radicals or C₁-C₄ hydroxyalkyl radicals.

4. Cationic 7-amino-l,2,3,4-tetrahydroquinoline according to any of the preceding claims, in which -R is a radical of formula:

-C(0)-CH₂ (B-AK)p-CAT⁺

in which:

B represents an oxygen atom or a radical NRi in which Ri represents a hydrogen atom or a C₁-C₄ alkyl radical or a C₁-C₄ hydroxyalkyl radical;

AK represents a linear or branched, saturated C₁-C₁₀ hydrocarbon chain which is optionally substituted by one or more hydroxyl radicals;

p = 0, 1 or 2;

CAT⁺ represents a cationic heterocyclic radical or a tri-Ci-C₄- alkylammonium radical.

5. Cationic 7-amino-l,2,3,4-tetrahydroquinoline according to Claim 4, in which CAT+ represents a cationic radical selected from the following:

- a cationic heterocyclic radical selected from imidazoliums, pyridiniums, pyrimidiniums, benzimidazoliums, thiazoliums, piperaziniums, pyrrolidiniums, morpholiniums and piperidiniums which are optionally substituted by one or more identical or different radicals selected from linear or branched C1-C4 alkyl radicals and C1-C4 hydroxyalkyl radicals;

- a tri-Ci-C4-alkylammonium radical selected from trimethyl- ammonium, triethylammonium, dimethylethylammonium, diethyl- methylammonium, diisopropylmethylammonium and diethyl- propyl ammonium.

6. Cationic 7-amino-l,2,3,4-tetrahydroquinoline according to Claim 4, in which CAT⁺ represents a cationic radical selected from the following:

- a cationic heterocyclic radical selected from imidazoliums, piperaziniums, pyrrolidiniums, morpholiniums and piperidiniums which are optionally substituted by one or more identical or different radicals selected from linear or branched C1-C4 alkyl radicals and C1-C4 hydroxyalkyl radicals;

- a tri-Ci-C4-alkylammonium radical selected from trimethyl- ammonium and triethylammonium.

7. Cationic 7-amino-l,2,3,4-tetrahydroquinoline according to any of the preceding claims, in which R₂, R3, R4, R5, R₆ and R₇, independently of one another, are selected from a hydrogen atom and C1-C4 alkyl radicals

8. Cationic 7-amino-l,2,3,4-tetrahydroquinoline according to any of the preceding claims, in which Ra, Rb and Rc are hydrogen atoms.

9. Cationic 7-amino-l,2,3,4-tetrahydroquinoline according to any of the preceding claims, selected from the following compounds:

10. Process for synthesis of a cationic 7-amino-l, 2,3,4- tetrahydroquinoline of general formula (I) as defined in any of Claims 4 to 6 and 9, in which the radicals R' and R" represent hydrogen atoms,

from a 7-nitro-l,2,3,4-tetrahydroquinoline of formula (II):

where the radicals R₂, R3 , R4 , R5 , R₆, R7 and Ra, Rb and Rc are as defined in Claim 1 ,

said process comprising at least the following steps, in this order:

• acylation o f the NH group in position 1 , using a haloacetyl halide,

· if p = 1 or 2, replacing the halogen in the group carried by the N atom in position 1 by a group HB-AK-X where X is a halogen,

• replacing the halogen in the group carried by the N atom in position 1 by the cationic group CAT⁺ or by an aminoalcoho late or an amine, to give a precursor of the cationic group,

· cationization o f the precursor, if the product obtained in the preceding step is not cationic,

• reduction o f the nitro group .

1 1 . Use o f a cationic 7-amino- l ,2,3 ,4-tetrahydroquinoline o f formula (I) as defined in any o f Claims 1 to 9 as a coupler for the dyeing o f keratin fibres, more particularly human keratin fibres such as the hair.

12. Cosmetic dyeing composition comprising, in a medium appropriate for dyeing, at least one cationic 7-amino- l , 2,3 ,4- tetrahydroquinoline o f formula (I) as defined in any o f Claims 1 to 9.

13 . Composition according to Claim 12, characterized in that it is a ready-to-use composition comprising at least one oxidizing agent selected from hydrogen peroxide, urea peroxide, alkali metal bromates, persalts, peracids and oxidase enzymes .

14. Method of dyeing keratin fibres, characterized in that the composition according to Claim 12 is applied to said fibres for a time sufficient to develop the desired co loration in the presence o f an oxidizing agent, the oxidizing agent being applied before, simultaneously with or after the composition.

15. Multi-compartment device, a first compartment containing the cosmetic composition for dyeing keratin fibres as defined in Claim 12, and a second compartment containing an oxidizing agent.