WO2007122340A1

WO2007122340A1 - Cationic dichromophoric compound containing two units of hydrazone type and comprising a cationic linker arm, dye composition comprising at least one such compound, method for the use thereof and uses

Info

Publication number: WO2007122340A1
Application number: PCT/FR2007/051110
Authority: WO
Inventors: Hervé David; Andrew Greaves; Bérangère Baril
Original assignee: L'oréal
Priority date: 2006-04-13
Filing date: 2007-04-13
Publication date: 2007-11-01

Abstract

The present application relates to a novel family of cationic dichromophoric compounds containing two units of hydrazone type connected by a cationic linker arm, which can be used as a direct dye, and to a dye composition for dyeing keratin fibres, in particular human keratin fibres such as the hair, comprising at least one such compound in a suitable dyeing medium. The present application also relates to the dyeing method using this composition and to the uses thereof.

Description

CATIONIC DICHROMOPHORIC COMPOUND HAVING TWO HYDRAZONE AND CATIONIC BOND ARRAY MOTIFS, TINCTORIAL COMPOSITION COMPRISING AT LEAST ONE SUCH COMPOUND, PROCESS FOR CARRYING OUT AND USES

The subject of the present application is a new family of particular compounds of the cationic dichromophoric type comprising two units of the hydrazone type linked by a cationic linker, their use as direct dyes for dyeing keratinous fibers and also dyeing compositions for the dyeing process. dyeing keratinous fibers comprising in a suitable dyeing medium at least one such cationic dichromophoric compound comprising two units of hydrazone type connected by a cationic linker.

It is known to dye keratinous fibers and in particular human hair with dyeing compositions containing oxidation dye precursors, generally known as oxidation bases, such as ortho- or para-phenylenediamines, ortho- or para-phenylenediamines. aminophenols and heterocyclic compounds. These oxidation bases are colorless or weakly colored compounds which, when combined with oxidizing products, can give rise to colored 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 color modifiers, the latter being chosen in particular from aromatic meta-diamines, meta-aminophenols, meta-aminophenols and meta-aminophenols. diphenols and certain heterocyclic compounds such as indole compounds. The variety of molecules involved in the oxidation bases and couplers allows a rich palette of colors to be obtained.

This oxidation dyeing process consists in applying to the keratinous fibers oxidation bases or a mixture of oxidation bases and couplers with an oxidizing agent, for example hydrogen peroxide, to be allowed to pause, then to rinse the fibers. The resulting colorations are permanent, strong, and resistant to external agents, including light, weather, washing, perspiration and friction. Generally applied at basic pH, the compositions make it possible to obtain a dyeing and at the same time a lightening of the fiber, which in practice results in the possibility of obtaining a final coloration that is lighter than the original color. In addition, the lightening of the fiber has the advantageous effect of generating a solid color in the case of gray hair, and in the case of naturally pigmented hair, to bring out the color, that is to say to make it more visible. It is also known to dye keratinous fibers by direct dyeing. The method conventionally used in direct dyeing consists in applying to the keratin fibers direct dyes which are colored and dyestuff molecules having an affinity for the fibers, allowing them to be paused and then rinsing the fibers. It is known, for example, to use direct dyes of the nitrobenzene, anthraquinone, nitropyridine type, azo, xanthene, acridine, azine dyes or triarylmethane dyes, for example.

The resulting colorations are particularly chromatic colorations which are however temporary or semi-permanent. Indeed, the nature of the interactions that bind the direct dyes to the keratinous fiber, and their desorption of the surface and / or the core of the fiber, make the dyeing power and the resistance to washing or transpiration of the colorings still possible. considered insufficient. Some direct dyes may also be sensitive to light because of the low resistance of the chromophore to photochemical attacks and lead over time to a fading of the hair coloring.

It is known to use direct dyes in combination with oxidizing agents. However, the direct dyes may be sensitive to the action of oxidizing agents such as hydrogen peroxide, and reducing agents such as sodium bisulfite, which makes them generally difficult to use under these conditions. There is therefore a real need to look for direct chromatic dyes which make it possible to dye the keratinous fibers as powerfully as the oxidation dyes, which are as stable as themselves in the light, which are also resistant to bad weather, washing and drying. transpiration, and furthermore, sufficiently stable in the presence of oxidizing and reducing agents to be able to simultaneously obtain a lightening of the fiber either by use of direct lightening compositions containing them, or by the use of oxidation dyeing compositions containing them . There is also a real need to look for direct dyes that can dye keratin fibers to obtain a very wide range of colors, especially very chromatic, not to mention the so-called "fundamental" shades such as blacks and chestnuts and shades to reflections.

Surprisingly and advantageously, it has been discovered a new family of cationic dichromophoric compounds comprising two units of the hydrazone type connected by a cationic linker, which can be used as direct dyes for dyeing keratinous fibers, in particular human keratinous fibers. such as hair. The dye compositions comprising at least one cationic dichromophoric compound comprising two hydrazone-type units connected by a cationic linker, make it possible to obtain chromatic shades, so-called fundamental shades such as blacks and chestnuts, and shades with reflections. The compositions according to the present application make it possible to obtain dyes resistant to external agents (sun, bad weather) as well as to shampoos and perspiration.

In addition, these compositions have an improved rise. The subject of the invention is also a process for dyeing keratinous fibers from cationic dichromophoric compounds comprising two hydrazone-type units connected by a cationic linker as well as the use of these compounds to obtain dyes having good resistance to external agents and shampoos.

Within the meaning of the present invention, and unless a different indication is given: An alkyl (en) radical or the alkyl (en) part of a radical is linear or branched,

An alkyl (en) radical or the alkyl (en) part of a radical are said to be "substituted" when they comprise at least one substituent chosen from the groups:

• hydroxyl, alkoxy, -C ₄ (poly) hydroxyalkoxy, C ₂ -C _4,

Amino optionally substituted with one or two identical or different alkyl groups dC ₄ optionally bearing at least one hydroxyl group or C ₁ -C ₂ alkoxy, said alkyl radicals being able to form with the nitrogen atom to which they are attached a saturated or unsaturated, optionally aromatic, substituted or unsubstituted 5- to 7-membered heterocycle optionally comprising at least one other heteroatom different from or different from nitrogen; • A alkylcarbonylamino radical (R'CO-NR-) in which the R radical is a hydrogen atom or an alkyl radical in C ₄ and the radical R 'is an alkyl radical C ₁ -C ₄

An alkylsulphonyl radical (R-SO ₂ -) in which the radical R represents a C ₁ -C ₄ alkyl radical. An alkylsulfinyl radical (R-SO-) in which the radical R represents a C ₁ -C ₄ alkyl radical.

An alkylcarbonyl radical (R-CO-) in which the radical R represents a C ₁ -C ₄ alkyl radical.

A radical (hetero) cyclic, saturated or unsaturated, aromatic or otherwise, or the (hetero) cyclic portion, saturated or unsaturated, aromatic or otherwise, of a radical are said to be "substituted" when they comprise at least one substituent, from preferably carried by a carbon atom, chosen from: a C 1 -C ₆ , preferably C ₁ -C ₈ , alkyl radical which is optionally substituted;

A halogen atom such as chlorine, fluorine or bromine; a hydroxyl group; A C ₁ -C ₄ alkoxy radical; a (C ₂ -C ₄ ) polyhydroxyalkoxy radical; an amino radical optionally substituted with one or two identical or different C ₁ -C ₄ alkyl radicals, optionally carrying at least one hydroxyl or amino group or (mono- or di-) alkylamino at dC ₄ or C ₁ -C alkoxy; C ₂ ; the two alkyl radicals which can form, with the nitrogen atom to which they are attached, a heterocycle containing 1 to 3 heteroatoms, preferably 1 to 2 heteroatoms, chosen from N, O, S, preferably N, the heterocycle comprising 5 to 7 members, being saturated or unsaturated, and aromatic or nonaromatic, and optionally substituted by one or more radicals identical or not selected from hydroxy, amino, (di) alkylamino, C ₁ -C ₄ alkyl C ₁ -C ₄ alkoxycarbonyl C ₁ -C ₄ ;

An alkylcarbonylamino radical (R'CO-NR-) in which the radical R is a hydrogen atom, a C ₁ -C ₄ alkyl radical and the radical R 'is a C ₁ -C ₄ alkyl radical;

An aminocarbonyl radical ((R) ₂ N-CO-) in which the radicals R, which may be identical or different, represent a hydrogen atom or a C ₁ -C ₄ alkyl radical;

An alkylsulphonylamino or arylsulphonylamino radical (R ¹ SO ₂ -NR-) in which the radical R represents a hydrogen atom, a C ₁ -C ₄ alkyl radical and the radical R 'represents a C ₁ -C alkyl radical; ₄ , a phenyl radical;

An aminosulfonyl radical ((R) ₂ N-SO ₂ -) in which the radicals R, which may be identical or different, represent a hydrogen atom or a C ₁ -C ₄ alkyl radical;

A thiol radical;

• a C ₁ -C ₈ , preferably C ₁ -C ₄ alkylthio radical, linear or branched, substituted or unsubstituted;

A hydroxycarbonyl (-COOH) radical in acid or salified form (preferably with an alkali metal or an ammonium, substituted or unsubstituted);

• a nitrile group (CN); a trifluoromethyl group (CF ₃ ); an alkylsulphonyl radical (RSO ₂ -) in which R represents a C ₁ -C ₄ alkyl radical

a hydrocarbon chain is unsaturated when it comprises one or more double bonds and / or one or more triple bonds; a heterocyclic radical corresponds to a cyclic radical whose cyclic part contains at least one heteroatom chosen from nitrogen, oxygen or sulfur;

two COL chromophores are said to be different when the chemical structure of the chromophores is different, or when the chromophores have the same chemical structure, then the substituents are different from one chromophore to another, or when the chromophores have the same structure chemical and identical radicals, the respective positions of said radicals is different from one chromophore to another.

In addition, unless otherwise indicated, the bounds defining the range of a range of values are within this range of values.

The compounds of the invention are cationic dichromophoric compounds comprising two units of the hydrazone type connected by a cationic linker corresponding to the general formula (I), its resonant forms, its addition salts with an acid, and its solvates:

COL -L-COL (I) in which each of the chromophores COL, identical or different, corresponds to the formulas (Ia), (Ib), (Ic), (Id), (Ie), (If) and (Ig) following , and preferably in the formulas (Ia), (Ic) and (Ie):

(Ic) (Id)

in which: - the radical Ri represents

- a hydrogen

- an alkyl radical in C1-C20, preferably CRCI _6, saturated or unsaturated, optionally substituted, optionally interrupted by one or more heteroatoms and / or by one or more groups comprising at least one heteroatom, preferably selected from oxygen , nitrogen, sulfur, CO, SO ₂ or combinations thereof; the alkyl radical having no nitro, nitroso, peroxo or diazo function.

an optionally substituted phenyl radical

an optionally substituted benzyl radical

an alkylcarbonyl radical (R-CO-) in which R represents an alkyl radical C _r C ₄

an alkylsulphonyl radical (RSO ₂ -) in which R represents an alkyl radical C _r C ₄

an aminosulfonyl radical ((R) ₂ N-SO ₂ -) in which the radicals R independently of one another represent an alkyl radical dC ₄ - an aminocarbonyl radical (R) ₂ N-CO-) in which the radicals R independently of each other, represent a hydrogen atom or an alkyl radical C _r C ₄

the radical R ₅ represents a C 1 -C 20, preferably C 1 -C 16, alkyl radical which is optionally substituted, optionally interrupted by one or more heteroatoms and / or by one or more groups comprising at least one heteroatom, preferably chosen from oxygen, nitrogen, sulfur, CO, SO, SO2 or combinations thereof; the alkyl radical having no nitro, nitroso, peroxo or diazo function. an optionally substituted phenyl radical

an optionally substituted benzyl radical

the radicals R ₂ and R ₃ , independently of one another, identical or different, represent:

. a halogen atom preferably selected from bromine, chlorine or fluorine;

A saturated or unsaturated, optionally substituted C ₁ -C ₁₆ alkyl radical, optionally interrupted by one or more heteroatoms and / or by one or more groups comprising at least one heteroatom preferably chosen from oxygen, nitrogen, sulfur, CO, SO, SO ₂ or combinations thereof; the alkyl radical having no nitro, nitroso, peroxo or diazo function.

• a hydroxyl group;

. a C ₁ -C ₄ alkoxy group; a C ₂ -C ₄ (poly) hydroxyalkoxy group; An alkoxycarbonyl group (RO-CO-) in which R represents a C ₁ -C ₄ alkyl radical,

An alkylcarbonyloxy radical (RCO-O-) in which R represents an alkyl radical in dC ₄ ;

An optionally substituted aryloxy group; An amino group optionally substituted with one or two identical or different C ₁ -C ₄ alkyl radicals, optionally carrying at least one hydroxyl or C ₁ -C ₂ alkoxy group, said alkyl radicals possibly being able to form with nitrogen atom to which they are attached, an optionally substituted, optionally aromatic, saturated or unsaturated 5- or 7-membered heterocycle, optionally comprising another heteroatom identical to or different from the nitrogen optionally substituted by a phenyl, aminophenyl, 4- radical; N, N-diethylaminophenyl or methoxyphenyl.

. an alkylcarbonylamino group (RCO-NR'-) in which the radical R represents a C ₁ -C ₄ alkyl radical and the radical R 'represents a hydrogen atom or a C ₁ -C ₄ alkyl radical;

An aminocarbonyl group ((R) ₂ N-CO-) in which the radicals R independently of one another represent a hydrogen atom or a C ₁ -C ₄ alkyl radical;

A ureido group (N (R) ₂ -CO-NR'-) in which the radicals R and R ', independently of each other, represent a hydrogen atom or a C ₁ -C ₄ alkyl radical;

. an aminosulphonyl group ((R) ₂ N-SO ₂ -) in which the radicals R independently of one another represent a hydrogen atom or a C ₁ -C ₄ alkyl radical; . an alkylthio group (RS-) in which the group R represents a C ₁ -C ₄ alkyl radical;

• an alkylsulfonylamino group (RSO ₂ -NR'-) in which the radical R 'represents a hydrogen atom or an alkyl radical in C ₁ -C _4, and the radical R represents an alkyl radical -C _4; . a cyano group;

• a trifluoromethyl group (CF ₃ ); . a thio radical (HS-)

. an alkylsulfinyl radical (RSO-) in which the radical R represents a C ₁ -C ₄ alkyl radical;

. an alkylsulphonyl radical (RSO ₂ -) in which the radical R represents a C ₁ -C ₄ alkyl radical;

- R ₁ may also form with a group R ₂ in ortho of the group NR ₁ and with the nitrogen atom substituted by R ₁ , a saturated or unsaturated heterocycle with 5 or 6 members, substituted or unsubstituted;

- Two adjacent radicals R ₂ can form between them and with the carbon atoms to which they are connected an aromatic cyclic radical or not 5 or 6-membered, substituted or unsubstituted; - Two adjacent R ₃ radicals can form between them and with the carbon atoms to which they are attached, a 5- or 6-membered aromatic ring, substituted or unsubstituted;

the radicals R ₄ , independently of each other, identical or different, represent:

• a hydrogen atom;

A saturated or unsaturated, optionally substituted C ₁ -C ₁₆ alkyl radical, optionally interrupted by one or more heteroatoms and / or by one or more groups comprising at least one heteroatom preferably chosen from oxygen, nitrogen, sulfur, CO, SO, SO ₂ , or combinations thereof; the alkyl radical having no nitro, nitroso, peroxo or diazo function.

. an amino group optionally substituted with one or two identical or different C ₁ -C ₄ alkyl radicals optionally carrying at least one hydroxyl or C ₁ -C ₂ alkoxy group, said alkyl radicals possibly being able to form with the atom nitrogen to which they are attached, a 5- or 6-membered saturated or unsaturated or aromatic heterocycle optionally substituted, optionally comprising at least one other heteroatom identical to or different from nitrogen; . an alkylcarbonylamino group (RCO-NR'-) in which the radical R represents a C ₁ -C ₄ alkyl radical and the radical R 'represents a hydrogen atom or a C ₁ -C ₄ alkyl radical;

. a ureido group (N (R) ₂ -CO-NR'-) in which the radicals R and R ', independently of each other, represent a hydrogen atom or a C ₁ -C ₄ alkyl radical;

An alkylsulphonylamino group (RSO ₂ -NR'-) in which the radical R 'represents a hydrogen atom or an alkyl radical in dC ₄ , and the radical R represents a C ₁ -C ₄ alkyl radical; An optionally substituted phenyl radical

. an optionally substituted benzyl radical.

- n is an integer between 0 and 5, when n is less than 5, the unsubstituted carbon atom (s) bears (s) a hydrogen atom; - is an integer between 0 and 4, when n 'is less than 4, the unsubstituted carbon atom (s) carries (s) a hydrogen atom;

- n "is an integer between 0 and 2, when n" is less than 2, the unsubstituted carbon atom (s) carries (s) a hydrogen atom.

the bond resulting from the formulas (Ia), (Ib), (Ic), (Id), (Ie), (If) and (Ig) connects each of the COL chromophores to the cationic L bonding arm of the formula (I) );

The electroneutrality of the compounds of formula (I) is provided by one or more cosmetically acceptable anions An, which may be identical or different.

An is an anion or a mixture of organic or inorganic anions making it possible to balance the charge (s) of the compounds (Ia), (Ib), (Ic), (Id), (Ie), (If) and (Ig) ).

More particularly, the cationic L bonding arm is a chain that isolates each of the chromophores so as to stop the electronic delocalization of each of the chromophores.

According to one variant, the cationic linking arm L linking the two hydrazone-type chromophores represents a C ₂ -C ₄₀ alkylene radical bearing at least one cationic charge, optionally substituted and / or optionally interrupted by one or more (hetero) saturated or unsaturated ring, aromatic or otherwise, identical or different, comprising from 3 to 7 ring members and / or optionally interrupted by one or more heteroatoms or groups comprising at least one heteroatom or combinations thereof, such as for example oxygen, nitrogen sulfur, a group -CO-, -SO-, -SO ₂ - or combinations thereof; the cationic L bonding arm not comprising azo, nitro, nitroso, peroxo bond; it being understood that the connecting arm L carries at least one cationic charge.

Preferably, the compounds of formula (I) according to the present invention are such that the radicals R 1 are identical and preferably represent a hydrogen atom or a C ₁ -C ₄ alkyl radical, optionally substituted by one or more radicals chosen from radicals hydroxy, alkoxy, CrC _2, amino, (di) alkylamino, C ₁ -C ₂ alkyl; an alkylcarbonyl radical (R-CO-) in which the radical R represents an alkyl radical in dC ₄ ; an aminocarbonyl group ((R) ₂ N-CO-) in which the radicals R independently of one another represent a hydrogen atom or a C ₁ -C ₄ alkyl radical; an alkylsulphonyl radical (R-SO ₂ -) in which the radical R represents a C ₁ -C ₄ alkyl radical; an optionally substituted phenyl radical; an optionally substituted benzyl radical.

According to a particularly preferred embodiment, the radicals R ₁ are identical and preferably represent a hydrogen atom, a methyl, ethyl, 2-hydroxyethyl, 2-methoxyethyl, acetyl (CH ₃ CO-) or methylsulfonyl (CH ₃ SO) radical. ₂ -), phenyl, benzyl optionally substituted by one or more hydroxy, amino or combination thereof.

According to a more particular variant of the invention, R ₁ represents a hydrogen atom; a methyl radical; a 2-hydroxyethyl radical; a radical CH ₃ CO-, a radical CH ₃ SO ₂ -; an unsubstituted benzyl radical.

According to another preferred variant, R ₁ may also form with a group R ₂ ortho of the group NR ₁ and with the nitrogen atom substituted by R ₁ , a saturated or unsaturated 5- or 6-membered heterocycle substituted with one or more alkyl radicals.

According to a particularly preferred embodiment, n is 0, 1 or 2, and / or n 'is 0, 1 or 2, and / or n is 0, 1 or 2.

When n or n 'or n "other than zero, the radicals R ₂ and R ₃ represent preferably and independently of one another:

a hydroxyl radical;

a halogen atom chosen from bromine, chlorine or fluorine;

a C ₁ -C ₄ alkyl radical, optionally substituted by one or more radicals, which are identical or different, chosen from hydroxyl and C ₁ -C ₂ alkoxy radicals; hydroxyalkoxy, C ₂ -C ₄ alkyl, amino, (di) alkylamino -C _2, thio (-SH), alkyl (Ci-C ₄₎ sulfinyl, (C _r -C ₄₎ alkylsulfonyl, thioalkyl (dC ₄₎

a C ₁ -C ₄ alkoxy radical;

a (poly) -hydroxyalkoxy (C ₂ -C ₄₎ radical; an amino radical;

a (C ₁ -C ₆ ) alkylamino radical, said alkyl radicals possibly being able to form, with the nitrogen atom to which they are attached, a saturated 5- or 7-membered heterocycle optionally comprising at least one other heteroatom which is identical to or different from the nitrogen; a (poly) -hydroxyalkylamino (C ₂ -C ₄₎ radical;

a phenylamino radical (PhNH-), a dC ₄ alkoxyphenylamino radical (ROPhNH-), a (C ₁ -C ₄ ) (di-) (alkyl) aminophenylamino radical (RR ¹ NPhNH-);

a (di-) (alkyl) aminocarbonyl radical ((R) ₂ N-CO-) in which the radicals R independently of one another represent a hydrogen atom or a C ₁ -C ₄ alkyl radical;

an alkylsulphonylamino radical (RSO ₂ NR'-) in which the radical R represents a C ₁ -C ₄ alkyl radical and the radical R 'represents a hydrogen atom or a C ₁ -C ₄ alkyl radical;

a (di-) (alkyl) aminosulphonyl radical ((R) ₂ NSO ₂ -) in which the radicals R independently of one another represent a hydrogen atom or a C ₁ -C ₄ alkyl radical;

an alkylcarbonylamino radical (R'CONR-) in which the radical R 'represents an alkyl radical in dC ₄ and the radical R represents a hydrogen atom or a Ci-C ₄ alkyl radical; an alkylthio radical (RS-) in which the radical R represents an alkyl radical

CrC ₄ ;

a thio radical (HS-);

- alkylsulfinyl radical (RSO-) in which the radical R represents an alkyl radical Ci-C _4; an alkylsulphonyl radical (R-SO ₂ -) in which the radical R represents a C ₁ -C ₄ alkyl radical;

According to a particular embodiment of the invention, when n or n 'or n "other than zero, the radicals R ₂ and R ₃ represent and independently of one another:

a hydroxyl radical; - a chlorine atom;

- an alkyl radical in C _4, optionally substituted by hydroxy, alkoxy -C _2;

a C ₁ -C ₄ alkoxy radical;

an amino radical; a (C ₁ -C ₆ ) alkylamino radical, said alkyl radicals possibly being able to form, with the nitrogen atom to which they are attached, a saturated 5-membered heterocycle;

- a radical alcoxyphénylamino C ₁ -C ₄ (ROPhNH-), a (di -) (alkyl) aminophenylamino -C ₄ (RR ¹ NPhNH-).

Preferably, when n or n 'or n "other than zero, the radicals R ₂ and R ₃ independently of each other preferably represent a chlorine atom, a methyl, ethyl, 2-hydroxyethyl or 2-methoxyethyl radical. methylsulfonyl (CH ₃ SO ₂ -), methylcarbonylamino (CH ₃ CONH-), hydroxyl, amino, methylamino, dimethylamino, (di) -ethylamino, (di) -2-hydroxyethylamino, methoxy, ethoxy, pyrrolidine, 4-methoxyphenylamino, 4-aminophenylamino, 4-N, N-diethylaminophenylamino.

As regards the R ₄ radicals, independently of one another, the latter preferably represent: • a hydrogen atom;

. a C ₁ -C ₄ alkyl radical optionally substituted by one or more radicals chosen from hydroxyl, C ₁ -C ₂ alkoxy, (C ₂ -C ₄ ) (poly) hydroxyalkoxy, amino, (C ₁ -C ₄ ) alkylamino radicals; ₁ -C ₂ , thio (-SH), (C ₁ -C ₄ ) alkylsulfinyl, alkylsulphonyl, thioalkyl (C 1 -C ₄ ); preferably a C ₁ -C ₄ alkyl radical optionally substituted by a hydroxyl radical.

. an amino group optionally substituted by one or more identical or different C ₁ -C ₄ alkyl radicals, optionally carrying at least one hydroxyl group,

An alkylcarbonylamino group (RCO-NR-) in which the radicals R independently of each other represent a C ₁ -C ₄ alkyl radical;

An alkylsulphonylamino group (RSO ₂ -NR'-) in which the radicals R, R ', independently of each other, represent a hydrogen atom or a C ₁ -C ₄ alkyl radical;

. a phenyl radical optionally substituted with one or more radicals chosen from hydroxyl, C ₁ -C ₂ alkoxy and (C ₂ -C ₄ ) (poly) hydroxyalkoxy, amino radicals,

(di) alkylamino, C ₁ -C ₂ alkyl, thio (-SH), (C ₁ -C ₄₎ alkylsulfonyl, alkylthio (C-ι-C _4); preferably a phenyl radical optionally substituted with a radical chosen from hydroxyl and amino radicals.

. a benzyl radical optionally substituted by one or more radicals chosen from hydroxyl, C ₁ -C ₂ alkoxy, (C ₂ -C ₄ ) (poly) hydroxyalkoxy, amino, (C ₁ -C ₂ ) di (C ₁ -C ₂₎ alkyl, thio radicals; (-SH), (C ₁ -C ₄ ) alkylsulphonyl, (C ₁ -C ₄ ) alkylthio, preferably a benzyl radical optionally substituted with a radical chosen from hydroxyl and amino radicals.

Even more preferably, the radicals R _{4, which may be} identical or different, represent a hydrogen, a methyl or ethyl radical,

2-hydroxyethyl, an amino radical, a methylcarbonylamino group (CH ₃ CO-NH-); a ureido group (N (R) ₂ -CO-NR'-) in which the radical R represents a C ₁ -C ₄ alkyl radical and R 'represents a hydrogen atom or a C ₁ -C ₄ alkyl radical; a methylsulfonylamino group (CH ₃ SO ₂ -NH-); a phenyl radical optionally substituted with at least one hydroxyl and / or amino group or combination thereof. a benzyl radical optionally substituted with at least one hydroxyl and / or amino group or combination thereof.

Preferably, the compounds of formula (I) according to the present invention are such that the radicals R ₅ of the same chromophore COL are identical and represent a C ₁ -C ₄ alkyl radical _, optionally substituted with one or more identical radicals or not selected from hydroxy, alkoxy C ₁ -C ₂ alkyl, amino, (di) alkylamino, C ₁ - C _2; an optionally substituted phenyl radical; an optionally substituted benzyl radical. According to a particularly preferred embodiment, the radicals R ₅ of the same chromophore COL are identical and represent a methyl, ethyl, 2-hydroxyethyl, 2-methoxyethyl, phenyl or benzyl radical optionally substituted with at least one hydroxyl and / or one amino.

According to a particular embodiment, in formulas (Ia) and (Ic) n 'is equal to

And each of two groups of two adjacent R ₃ radicals forms an aromatic radical, preferably benzene.

According to another variant, in the formulas (Ia), (Ib), (Ic), is not equal to 2, and the two radicals R ₃ are adjacent and form an aromatic radical, preferably benzene.

According to another variant, in the formulas (Ie) or (If), n "is equal to 2, and the two radicals R ₃ are adjacent and form an aromatic radical, preferably benzene. With regard to the cationic L bonding arm, this advantageously represents a C ₂ -C ₂₀ alkylene radical:

1- interrupted by at least one group corresponding to the following formulas

In which: • Rg and R _10, independently of one another, represent a C ₁ -C e alkyl radical; a C ₁ -C ₆ monohydroxyalkyl radical; a C ₂ -C ₆ polyhydroxyalkyl radical; alkoxy (CrC ₆₎ alkyl -C _6; an aryl radical such as optionally substituted phenyl; an arylalkyl radical such as optionally substituted benzyl; a C ₁ -C ₆ aminoalkyl radical; a C ₁ -C ₆ aminoalkyl radical, the amine of which is substituted by one or two identical or different C ₁ -C ₄ alkyl radicals; a (C ₁ -C ₆ ) alkylsulphonyl radical;

• two radicals R ₉ can form together, with the nitrogen atom to which they are attached, a saturated or unsaturated ring, optionally substituted, with 5, 6 or 7 members;

• R _13, identical or different, represent a hydrogen atom, a halogen atom selected from bromine, chlorine or fluorine, an alkyl radical C ₁ -C ₆ monohydroxyalkyl radical, a C ₁ -C ₆ , a polyhydroxyalkyl radical in C ₂ -C _6, alkoxy C ₁ -C ₆ alkyl group, a (di) alkylamino, C ₁ -C ₄ alkyl, a hydroxycarbonyl group, an alkylcarbonyl C ₁ -C ₆ thioalkyl, C ₁ -C ₆ alkyl radical (-C ₆₎ alkylthio, an alkyl (Ci-C ₆₎ alkylsulfonyl, an optionally substituted benzyl radical, a phenyl radical optionally substituted by one or more radicals selected from methyl, hydroxyl amino, methoxy;

• An is an anion or a mixture of anions, organic or mineral;

Z is an integer from 0 to 3; if z <3, then the unsubstituted carbon atoms carry a hydrogen atom; "V is an integer equal to 1 or 2, preferably 1;

And optionally interrupted by one or more heteroatoms or groups comprising at least one heteroatom or combinations thereof, such as, for example, oxygen, nitrogen, sulfur, a group -CO-, a group -SO ₂ -; provided that there is no azo, nitro, nitroso or peroxo group or bond in the linker L; 3- and optionally substituted by one or more radicals chosen from hydroxyl, C ₁ -C ₂ alkoxy, (C ₂ -C ₄ ) (poly) hydroxyalkoxy, amino substituted by one or two linear C ₁ -C ₄ alkyl groups; ₂ optionally carrying at least one hydroxyl group.

According to one particular embodiment of formulas (a) and (d), Rg, R ₁ O, separately, are preferably chosen from a C ₁ -C ₆ alkyl radical, a C ₁ -C ₄ monohydroxyalkyl radical, a C ₂ -C ₄ polyhydroxyalkyl radical, an 8IcOXy (C ₁ -C ₆ ) alkyl C ₁ -C ₄ radical, a C ₂ -C ₆ dimethylaminoalkyl radical.

Even more preferably, R ₉ and R ₁₀ separately represent a methyl, ethyl, 2-hydroxyethyl radical.

According to a particular embodiment of formulas (b) and (c), R- ₁ 3 represents a hydrogen atom, a halogen atom chosen from chlorine and fluorine, and a C ₁ -C ₆ alkyl radical. a monohydroxylalkyle radical in C ₁ -C ₄ alkoxy C ₁ -C ₄ alkyl, a hydroxycarbonyl radical, an alkyl radical (C-ι-C ₆₎ alkylthio, amino radical disubstituted with an alkyl radical (C ₁ - C ₄ ).

According to an even more particular embodiment of formulas (b) and (c), R ₁₃ represents a hydrogen atom, a chlorine atom, a methyl, an ethyl, a 2-hydroxyethyl, a methoxy, a hydroxycarbonyl, a dimethylamino.

According to another even more particular embodiment of formulas (b) and (c), z is equal to 0.

Preferably, the compounds according to the invention, corresponding to the formulas (Ia) to (Ig), comprise an alkylene cationic linking arm interrupted by at least one group, preferably from one to three groups (a) and / or (b). ). Even more advantageously, the link arm is interrupted by two groups (a) and / or (b), preferably identical.

In the formulas of the compounds of formulas (I), An represents an anion or a mixture of anions, organic or inorganic, making it possible to balance the charge (s) of the compounds of formula (I), for example chosen from a halide such as chloride bromide, fluoride, iodide; a hydroxide; sulphate; a hydrogen sulfate; an alkyl sulphate for which the linear or branched alkyl part is C ₁ -C ₆ , such as the methyl sulphate or ethyl sulphate ion; carbonates and hydrogen carbonates; salts of carboxylic acids such as formate, acetate, citrate, tartrate, oxalate; the alkylsulfonates for which the linear or branched alkyl moiety is C ₁ -C ₆ such as the methylsulfonate ion; arylsulphonates for which the aryl part, preferably phenyl, is optionally substituted by one or more C ₁ -C ₄ alkyl radicals such as, for example, 4-tolylsulphonate; alkylsulfonyls such as mesylate.

The acid addition salts of the compounds of formulas (I) may be by way of example the addition salts with an organic or inorganic acid such as hydrochloric acid, hydrobromic acid or sulfuric acid. or (alkyl- or phenyl) sulfonic acids such as p-toluenesulfonic acid or methylsulfonic acid.

The solvates of the compounds of formulas (I), represent the hydrates of such compounds and / or the combination of a compound of formula (I), with a linear or branched alcohol in dC ₄ such as methanol, ethanol, isopropanol, n-propanol.

According to a particular embodiment, the compounds of formula (I) are represented by the following formulas, as well as their resonant forms and / or their addition salts with an acid and / or their solvates

Year

in which the radicals R 1, R ₂ , R 3, R ₄ , R 5, An, n, n ', n "and L are as defined above.

Preferably, the COL-L-COL cationic dichromophoric compounds of the invention are such that each of the COL chromophores, which are identical or different, corresponds to the formulas (Ia), (Ib), (Ic), (Id), (Ie) previously defined and L is a C ₂ -C ₃₀ alkylene radical interrupted by at least one group of formula (a) and / or (b), preferably interrupted by one to three groups (a) and / or (b), and even more preferably one or two identical groups (a) or (b).

Wherein R9 and R13 and z have the same meanings as above.

In particular, the cationic dichromophoric compounds comprising two hydrazone-type units connected by a cationic linker of formula (I) according to the present invention, are represented by the following compounds:

(M)

(Ll'h)

(Ll'i)

Preferably, the compounds of formula (a) to (z) and (M'a) to (ll'i) above according to the present invention are such that the radicals R 1 are identical and preferably represent: hydrogen atom a methyl, ethyl, 2-hydroxyethyl radical; an acetyl radical (CH ₃ CO-) - a methylsulfonyl radical (CH ₃ SO ₂ -) a benzyl radical optionally substituted by at least one hydroxyl, an amino.

A phenyl radical.

According to a particularly preferred embodiment, n is 0, 1 or 2, and / or n 'is 0, 1 or 2, and / or n "is 0, 1 or 2 and when n or n' or n" is different from zero, the radicals, the radicals R ₂ and R ₃ represent preferably and independently of one another:

a hydroxyl radical a methoxy radical

- a chlorine atom

a methyl or ethyl radical

an amino radical;

a (di) -2-hydroxyethylamino radical, a (di-) ethylamino radical a pyrrolidine radical

a methylcarbonylamino radical (CH ₃ CONH-)

a 4-methoxyphenylamino radical

a 4-aminophenylamino radical; a 4-N, N-diethylaminophenylamino radical;

two adjacent radicals R ₂ can form between them and with the carbon atoms to which they are connected a naphthalene-type ring

two adjacent radicals R ₃ may form between each other and with the carbon atoms to which they are attached a quinolinium type ring (in the case where the two radicals R ₂ are attached to a pyridine ring) and a benzimidazolium type ring in the case where the two R ₂ radicals are attached to an imidazolium ring)

. a methyl, ethyl, 2-hydroxyethyl radical

A methylcarbonylamino group (CH ₃ CO-NH-). a methylsulfonylamino group (CH ₃ SO ₂ -NH-)

A phenyl radical; a benzyl radical optionally substituted by one or more hydroxyl and / or amino radicals.

According to a particular embodiment, in the formulas (a) and (c) n 'is equal to 4 and each of the groups of two adjacent radicals R ₃ forms an aromatic radical, preferably benzene.

According to another variant, in the formulas (a), (b), (c), (f), (g), (h), (k), (I), (m), (p), (q), (r), (s), (t), (u), (IV), (w), (x), (z), (Ma '), (IIb), (IIe), (Hd), (IIe), (II'f), ( 11'g) or (11'i), n 'is equal to 2, and the two radicals R ₃ are adjacent and form an aromatic radical, preferably benzene.

According to another variant, in the formulas (d), (i), (n), (s), (t), (u), (y) (II) b), (11'c), (11'd), or (ll'h), n "is 2, and the two radicals R ₃ are adjacent and form an aromatic radical, preferably benzene.

The composition according to the invention advantageously comprises from 0.001 to 10%, preferably from 0.01 to 10%, by weight of compound (s) of the invention of formula (I), relative to the total weight of the composition. The composition according to the invention may contain one or more cationic dichromophoric compounds comprising two units of the hydrazone type connected by a cationic bonding arm of formula (I), the mixtures of these compounds then being possible in all relative proportions. The dyeing composition in accordance with the invention may also contain one or more additional direct dyes other than cationic dichromophoric direct dyes comprising two hydrazone-type units connected by a cationic bonding arm of formula (I), these additional dyes being able in particular to be chosen from neutral, acidic or cationic nitro dyes of the benzene series, acid or cationic neutral azo direct dyes, neutral, acidic or cationic quinone and in particular neutral anthraquinone dyes, azine direct dyes, triarylmethane direct dyes, Indoamine direct dyes, tetraazapentamethine type dyes and natural direct dyes. Among the benzene direct dyes that can be used according to the invention, mention may be made, without limitation, of the following compounds:

1,4-diamino-2-nitrobenzene,

- 1-amino-2-nitro-4-β-hydroxyethylaminobenzene

1-amino-2-nitro-4-bis (β-hydroxyethyl) -aminobenzene-1,4-bis (β-hydroxyethylamino) -2-nitrobenzene

1-β-hydroxyethylamino-2-nitro-4-bis (β-hydroxyethylamino) benzene

- 1-β-hydroxyethylamino-2-nitro-4-aminobenzene

1-β-hydroxyethylamino-2-nitro-4- (ethyl) (β-hydroxyethyl) -aminobenzene

1-amino-3-methyl-4-β-hydroxyethylamino-6-nitrobenzene-1-amino-2-nitro-4-β-hydroxyethylamino-5-chlorobenzene

- 1, 2-Diamino-4-nitrobenzene

- 1-amino-2-β-hydroxyethylamino-5-nitrobenzene

- 1, 2-Bis- (β-hydroxyethylamino) -4-nitrobenzene

1-amino-2-tris (hydroxymethyl) methylamino-5-nitrobenzene-1-hydroxy-2-amino-5-nitrobenzene

- 1-Hydroxy-2-amino-4-nitrobenzene

- 1-Hydroxy-3-nitro-4-aminobenzene

- 1-Hydroxy-2-amino-4,6-dinitrobenzene

1-β-hydroxyethyloxy-2-β-hydroxyethylamino-5-nitrobenzene-1-methoxy-2-β-hydroxyethylamino-5-nitrobenzene

- 1-β-hydroxyethyloxy-3-methylamino-4-nitrobenzene

- 1-β, γ-dihydroxypropyloxy-3-methylamino-4-nitrobenzene

- 1-β-hydroxyethylamino-4-β, γ-dihydroxypropyloxy-2-nitrobenzene

- 1-β, γ-dihydroxypropylamino-4-trifluoromethyl-2-nitrobenzene - 1-β-hydroxyethylamino-4-trifluoromethyl-2-nitrobenzene

- 1-β-hydroxyethylamino-3-methyl-2-nitrobenzene

- 1-β-aminoethylamino-5-methoxy-2-nitrobenzene

- 1-Hydroxy-2-chloro-6-ethylamino-4-nitrobenzene-1-hydroxy-2-chloro-6-amino-4-nitrobenzene

- 1-Hydroxy-6-bis- (β-hydroxyethyl) -amino-3-nitrobenzene

- 1-β-hydroxyethylamino-2-nitrobenzene

1-Hydroxy-4-β-hydroxyethylamino-3-nitrobenzene.

Among the azo direct dyes that may be used according to the invention, mention may be made of the cationic azo dyes described in the patent applications WO 95/15144, WO-95/01772 and EP-714954, the content of which forms an integral part of the invention.

Among these compounds, mention may be made of the following dyes:

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

1,3-dimethyl-2 - [(4-aminophenyl) azo] -1H-imidazolium chloride; 1-methyl-4 - [(methylphenylhydrozono) methyl] -pyridinium methylsulphate.

Mention may also be made, among the azo direct dyes, of the following dyes, described in COLOR INDEX INTERNATIONAL 3rd edition:

-Disperse Red 17

-Acid YeI low 9 -Acid Black 1

-Basic Red 22

-Basic Red 76

-Basic Yellow 57

-Basic Brown 16 -Acid Yellow 36

-Acid Orange 7

-Acid Red 33

-Acid Red 35

-Basic Brown 17 -Acid Yellow 23

-Acid Orange 24

-Disperse Black 9.

There may also be mentioned 1- (4'-aminodiphenylazo) -2-methyl-4bis- (β-hydroxyethyl) aminobenzene and 4-hydroxy-3- (2-methoxyphenylazo) -1-naphthalenesulfonic acid. Among the quinone direct dyes, mention may be made of the following dyes:

-Disperse Red 15

-Solvent Purple 13

-Acid Violet 43

-Disperse Violet 1 -Disperse Violet 4

-Disperse Blue 1

-Disperse Violet 8

-Disperse Blue 3 -Disperse Red 11

-Acid Blue 62

-Disperse Blue 7

-Basic Blue 22

-Disperse Violet 15 -Basic Blue 99 as well as the following compounds:

-1-N-4-hydroxyanthraquinone méthylmorpholiniumpropylamino-

-1-aminopropylamino-4-méthylaminoanthraquinone

-1-Aminopropylaminoanthraquinone -5-β-hydroxyethyl-1,4-diaminoanthraquinone

-2-Aminoéthylaminoanthraquinone

-1,4-Bis- (β, γ-dihydroxypropylamino) -anthraquinone.

Among the azine dyes, mention may be made of the following compounds:

-Basic Blue 17 -Basic Red 2.

Among the triarylmethane dyes that can be used according to the invention, mention may be made of the following compounds:

-Basic Green 1

-Acid blue 9 -Basic Violet 3

-Basic Violet 14

-Basic Blue 7

-Acid Violet 49

-Basic Blue 26 -Acid Blue 7

Among the indoamine dyes that can be used according to the invention, mention may be made of the following compounds:

2-β-hydroxyethylamino-5- [bis- (β-4'-hydroxyethyl) amino] anilino-1,4-benzoquinone

2-β-hydroxyethylamino-5- (2'-methoxy-4'-amino) anilino-1,4-benzoquinone-3-N (2'-chloro-4'-hydroxy) phenyl-acetylamino-6-methoxy- 1,4-benzoquinone imine

3-N (3'-Chloro-4'-methylamino) phenyl-ureido-6-methyl-1,4-benzoquinone imine

3- [4'-N- (ethyl, carbamylmethyl) amino] -phenyl-ureido-6-methyl-1,4-benzoquinone imine. Among the tetraazapentamethine type dyes that may be used according to the invention, mention may be made of the following compounds: 2 - ((E) - {(E) - [(1, 3-dimethyl-1,3-dihydro-2H) chloride imidazol-2-ylidene) hydrazono] methyl} diazenyl) -1,3-dimethyl-1H-imidazol-3-ium, the chloride of 2 - {(E) - [(1 Z) -N- (1, 3 1-dimethyl-1,3-dihydro-2H-imidazol-2-ylidene) ethane hydrazonoyl] diazenyl} -1,3-dimethyl-1H-imidazol-3-ium, 4-methoxy-2 - ((E ) - {(1 E) -1 - [(2E) - (4-methoxy-1-methylpyridin-2 (1H) -ylidene) hydrazono] ethyl} diazenyl) -1-methylpyridinium, 1-methyl-1-methyl-1-methylpyridinium chloride; 2 - ((E) - {(1E) - 1 - [(2E) - (1-methylpyridin-2 (1H) -ylidene) hydrazono] ethyl} diazenyl) pyridinium, 1- (2-hydroxyethyl) chloride 2 - [(E) - ((1E) -1 - {(2E) - [1- (2-hydroxyethyl) pyridin-2 (1H) -ylidene] hydrazono} ethyl) diazenyl] pyridinium, chloride 1-methyl-2 - ((E) - {(E) - [(2Z) - (1-methylpyridin-2 (1H) -ylidene) hydrazono] methyl} diazenyl) pyridinium, the acetate of 2-hydroxyethyl) -2 - [(E) - ((E) - {(2E) - [1- (2-hydroxyethyl) pyridin-2 (1H) ) Ylidene] hydrazono} methyl) diazenyl] pyridinium.

Among the additional natural direct dyes that can be used according to the invention, mention may be made of lawsone, juglone, alizarin, purpurin, carminic acid, kermesic acid, purpurogalline, protocatechaldehyde, indigo, isatin, curcumin, spinulosin, apigenidine. It is also possible to use the extracts or decoctions containing these natural dyes, and in particular poultices or extracts made from henna.

The additional direct dye (s) preferably represent from 0.001 to 20% by weight approximately of the total weight of the ready-to-use composition and even more preferentially from 0.005 to 10% by weight approximately.

The composition of the present invention may further comprise at least one oxidation base in admixture with at least one coupler, oxidation dye precursors. .

For example, if it (s) is (are) present (s), each oxidation base can be chosen from para-phenylenediamines, bis-phenylalkylenediamines, para-aminophenols, ortho-aminophenols, heterocyclic bases, as well as its salt (s) of addition with an acid.

Among the paraphenylenediamines, there may be mentioned, for example, para-phenylenediamine, paratoluylenediamine, 2-chloro-para-phenylenediamine, 2,3-dimethyl-para-phenylenediamine, 2,6-dimethyl-para-phenylenediamine, 2,6-diethyl paraphenylenediamine, 2,5-dimethyl-para-phenylenediamine, N, N-dimethyl-para-phenylenediamine, N, N-diethyl-para-phenylenediamine, N, N-dipropyl-para-phenylenediamine, 4-amino-N, N-diethyl-3-methylaniline, N, N- bis- (β-hydroxyethyl) paraphenylenediamine, 4-N, N-bis- (β-hydroxyethyl) amino-2-methylaniline, 4-N, N-bis- (β-hydroxyethyl) amino-2-chloroaniline, 2-β-hydroxyethyl paraphenylenediamine, 2-fluoro-para-phenylenediamine, 2-isopropyl paraphenylenediamine, N- (β-hydroxypropyl) paraphenylenediamine,

2-hydroxymethyl paraphenylenediamine, N, N-dimethyl-3-methyl-para-phenylenediamine, N, N- (ethyl, β-hydroxyethyl) para-phenylenediamine, N- (β, dihydroxypropyl) paraphenylenediamine, N- (4'-aminophenyl) paraphenylenediamine, N-phenyl-para-phenylenediamine, 2-β-hydroxyethyloxy-para-phenylenediamine, 2-β-acetylaminoethyloxy-para-phenylenediamine, N- (β-methoxyethyl) para-phenylenediamine, 4- aminophenylpyrrolidine, 2-thienyl paraphenylenediamine, 2-hydroxyethylamino-5-amino toluene, 3-hydroxy-1- (4'-aminophenyl) pyrrolidine and their addition salts with an acid.

Of the paraphenylenediamines mentioned above, paraphenylenediamine, paratoluylenediamine, 2-isopropyl paraphenylenediamine, 2-β-hydroxyethyl paraphenylenediamine, 2-β-hydroxyethyloxy paraphenylenediamine, 2,6-dimethyl paraphenylenediamine, 2,6 ethyl paraphenylenediamine, 2,3-dimethyl paraphenylenediamine, N, N-bis- (β-hydroxyethyl) paraphenylenediamine, 2-chloro-para-phenylenediamine, 2-β-acetylaminoethyloxy-para-phenylenediamine, and their addition salts with an acid are particularly preferred.

Among the bis-phenylalkylenediamines, mention may be made, by way of example, of N, N'-bis- (β-hydroxyethyl) N, N'-bis- (4'-aminophenyl) 1,3-diamino propanol, N N, N'-bis- (β-hydroxyethyl) N, N'-bis- (4'-aminophenyl) ethylenediamine, N, N'-bis- (4-aminophenyl) tetramethylenediamine, N, N'-bis- ( β-hydroxyethyl) N, N'-bis (4-aminophenyl) tetramethylenediamine, N, N'-bis (4-methylaminophenyl) tetramethylenediamine, N, N'-bis (ethyl) N, N ' -bis- (4'-amino, 3'-methylphenyl) ethylenediamine, 1,8-bis- (2,5-diamino phenoxy) -3,6-dioxaoctane, and their addition salts with an acid.

Examples of para-aminophenols include para-aminophenol, 4-amino-3-methylphenol, 4-amino-3-fluoro phenol, 4-amino-3-chlorophenol, 4- amino 3-hydroxymethyl phenol, 4-amino-2-methylphenol, 4-amino-2-hydroxymethylphenol, 4-amino-2-methoxymethylphenol, 4-amino-2-aminomethylphenol, 4-amino 2- (β hydroxyethyl aminomethyl) phenol, 4-amino-2-fluoro phenol, and their addition salts with an acid.

Among the ortho-aminophenols, mention may be made, for example, of 2-amino phenol, 2-amino-5-methylphenol, 2-amino-6-methylphenol and 5-acetamido-2-aminophenol, and their addition salts with an acid. Among the heterocyclic bases that may be mentioned by way of example are pyridine derivatives, pyrimidine derivatives and pyrazole derivatives.

Among the pyridine derivatives, mention may be made of 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-amino pyridine, 3,4-diamino pyridine, and their addition salts with an acid.

Other pyridinic oxidation bases useful in the present invention are the 3-amino pyrazolo [1, 5-a] -pyridines oxidation bases or their addition salts described for example in the patent application FR 2801308. By way of example, mention may be made of pyrazolo [1,5-a] pyridin-3-ylamine; 2-acetylamino pyrazolo [1,5-a] pyridin-3-ylamine; the 2-morpholin-4-yl-pyrazolo [1,5-a] pyridin-3-ylamine; 3-amino-pyrazolo [1,5-a] pyridin-2-carboxylic acid; 2-methoxy-pyrazolo [1,5-a] pyridin-3-ylamino; (3-Amino-pyrazolo [1,5-a] pyridin-7-yl) -methanol; 2- (3-Amino-pyrazolo [1,5-a] pyridin-5-yl) ethanol; 2- (3-Amino-pyrazolo [1,5-a] pyridin-7-yl) -ethanol; (3-amino-pyrazolo [1,5-a] pyridin-2-yl) -methanol; 3,6-diamino-pyrazolo [1,5-a] pyridine; 3,4-diaminopyrazolo [1,5-a] pyridine; pyrazolo [1,5-a] pyridine-3,7-diamine; 7-morpholin-4-yl-pyrazolo [1,5-a] pyridin-3-ylamine; pyrazolo [1,5-a] pyridine-3,5-diamine; 5-morpholin-4-yl-pyrazolo [1,5-a] pyridin-3-ylamine; 2 - [(3-Amino-pyrazolo [1,5-a] pyridin-5-yl) - (2-hydroxyethyl) amino] ethanol; 2 - [(3-amino-pyrazolo [1,5-a] pyridin-7-yl) - (2-hydroxyethyl) amino] ethanol; 3-amino-pyrazolo [1,5-a] pyridin-5-ol; 3-Amino-pyrazolo [1,5-a] pyridin-4-ol; 3-amino-pyrazolo [1,5-a] pyridin-6-ol; 3-aminopyrazolo [1,5-a] pyridin-7-ol; as well as their addition salts with an acid.

Among the pyrimidine derivatives, mention may be made of the compounds described, for example, in DE 2359399; JP 88-169571; JP 05-63124; EP 0770375 or patent application WO 96/15765 such as 2,4,5,6-tetraaminopyrimidine, 4-hydroxy 2,5,6-triaminopyrimidine, 2-hydroxy 4,5,6-triaminopyrimidine, , 4-dihydroxy-5,6-diaminopyrimidine, 2,5,6-triaminopyrimidine and their addition salts with an acid and their tautomeric forms, when tautomeric equilibrium exists. Among the pyrazole derivatives, mention may be made of the compounds described in DE 3843892, DE 4133957 and patent applications WO 94/08969, WO 94/08970, FR-A-2 733 749 and DE 195 43 988 as the 4.5 1-methyl pyrazole, 4,5-diamino 1- (β-hydroxyethyl) pyrazole, 3,4-diamino pyrazole, 4,5-diamino-1- (4'-chlorobenzyl) pyrazole, 4,5 1-diamino-1,3-dimethyl pyrazole, 4,5-diamino-3-methyl-1-phenylpyrazole, 4,5-diamino-1-methyl-3-phenylpyrazole, 4-amino-1,3-dimethyl-5-hydrazino pyrazole 1-Benzyl-4,5-diamino-3-methyl-pyrazole, 4,5-diamino-3-tert-butyl-1-methyl-pyrazole, 4,5-diamino-1-tert-butyl-3-methyl-pyrazole, 4, 5-diamino 1- (β-hydroxyethyl) 3-methyl pyrazole, 4,5-diamino-1-ethyl-3-methylpyrazole, 4,5-diamino-1-ethyl-3- (4'-methoxyphenyl) pyrazole, 4 5-diamino-1-ethyl-3-hydroxymethyl pyrazole, 4,5-diamino-3-hydroxymethyl-1-methyl-pyrazole, 4,5-diamino-3-hydroxymethyl-1-isopropyl pyrazole, 4,5-diamino 3-methyl-1-isopropyl pyrazole, 4-amino-5- (2'-aminoethyl) amino-1,3-dimethyl pyrazole, 3,4,5-triamino pyrazole, 1-methyl-3,4,5-triamino pyrazole 3,5-diamino-1-methyl-4-methylamino pyrazole, 3,5-diamino 4- (β-hydroxyethyl) amino-1-methyl pyrazole, and their addition salts with an acid.

The additional oxidation base (s) optionally present in the composition of the invention are generally present in an amount ranging from 0.001 to 20% by weight approximately of the total weight of the dyeing composition, preferably ranging from 0.005 to 6%. If the composition according to the invention contains at least one additional oxidation base, it also contains one or more couplers conventionally used for dyeing keratin fibers. Among these couplers, there may be mentioned in particular meta-phenylenediamines, meta-diphenols, naphthalenic couplers, heterocyclic couplers and their addition salts.

By way of example, mention may be made of 1,3-dihydroxybenzene, 1,3-dihydroxy-2-methylbenzene, 4-chloro-1,3-dihydroxybenzene and 2,4-diamino- (β- hydroxyethyloxy) benzene, 2-amino 4- (β-hydroxyethylamino) 1-methoxybenzene, 1,3-diamino benzene, 1,3-bis (2,4-diaminophenoxy) propane, 3-ureido aniline, 3-ureido-1-dimethylamino benzene, sesamol, 1-β-hydroxyethylamino-3,4-methylenedioxybenzene, α-naphthol, 2-methyl-1-naphthol, 6-hydroxyindole, 4-hydroxyindole, 4-hydroxy N-methylindole, 2-amino-3-hydroxypyridine, 6-hydroxybenzomorpholine 3,5-diamino-2,6-dimethoxypyridine, 1-N- (β-hydroxyethyl) amino-3 4-methylene dioxybenzene, 2,6-bis- (β-hydroxyethylamino) toluene and their addition salts.

In the composition of the present invention, if present, the coupler or couplers are generally present in an amount ranging from 0.001 to 20% by weight of the total weight of the dyeing composition, preferably ranging from 0.005 to 6%. In general, the addition salts of the oxidation bases and couplers that can be used in the context of the invention are chosen especially from the addition salts with an acid such as hydrochlorides, hydrobromides, sulphates, alkylsulphonic acids whose linear or branched alkyl part is C1-C6, for example methylsulphonic acid, for example citrates, succinates, tartrates, lactates, tosylates, optionally substituted arylsulphonic acids, such as, for example, benzenesulphonic acid or para-toluenesulfonic acid, phosphates and acetates.

The medium suitable for dyeing, also known as a dyeing medium, is a cosmetic medium generally consisting of water or a mixture of water and at least one organic solvent for solubilizing compounds that are not sufficiently soluble in water. water. As organic solvent, there may be mentioned, for example lower alkanols dC ₄ , such as ethanol and isopropanol; polyols and polyol ethers such as 2-butoxyethanol, propylene glycol, propylene glycol monomethyl ether, diethylene glycol monoethyl ether and monomethyl ether, as well as aromatic alcohols such as benzyl alcohol or phenoxyethanol, and mixtures thereof.

The solvents are preferably present in proportions preferably of between 1 and 40% by weight approximately relative to the total weight of the dye composition, and even more preferably between 5 and 30% by weight approximately. The dyeing composition in accordance with the invention may also contain various adjuvants conventionally used in compositions for dyeing hair, such as anionic, cationic, nonionic, amphoteric or zwitterionic surfactants or mixtures thereof, anionic, cationic, nonionic polymers. ionic, amphoteric, zwitterionic or mixtures thereof, inorganic or organic thickeners, and in particular anionic, cationic, nonionic and amphoteric polymeric associative thickeners, antioxidants, penetrating agents, sequestering agents, perfumes, buffers, dispersing agents, conditioning agents such as, for example, volatile or non-volatile silicones, modified or unmodified, film-forming agents, ceramides, preserving agents, opacifying agents.

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

Of course, one skilled in the art will take care to choose this or these optional additional compounds in such a way that the advantageous properties intrinsically attached to the dyeing composition according to the invention are not, or not substantially, impaired by the or the additions envisaged.

The pH of the dye composition according to the invention is generally between 3 and 12 approximately, and preferably between 5 and 11 approximately. It can be adjusted to the desired value by means of acidifying or alkalizing agents usually used for dyeing keratin fibers or else using conventional buffer systems.

Among the acidifying agents, mention may be made, by way of example, of mineral or organic acids such as hydrochloric acid, orthophosphoric acid, sulfuric acid, carboxylic acids such as acetic acid, tartaric acid, citric acid, lactic acid, sulphonic acids.

Among the alkalinizing agents that may be mentioned, by way of example, are ammonia, alkaline carbonates, alkanolamines such as mono-, di- and triethanolamines and their derivatives, sodium or potassium hydroxides and following formula (II):

N W - N

^Rc % l) wherein W is a propylene residue optionally substituted with a hydroxyl group or a C ₁ -C ₄ alkyl radical; R _3, R _b, R _c and R _d, identical or different, represent a hydrogen atom, an alkyl radical in C ₁ -C ₄ hydroxyalkyl or C ₁ -C _4. The dye composition according to the invention may be in various forms, such as in the form of liquids, creams, gels, pastes or in any form another form suitable for dyeing keratinous fibers, and in particular human hair.

The process of the present invention is a process in which the composition according to the present invention as defined above is applied to the fibers. According to a particular embodiment, the composition of the invention is applied to the keratinous fibers in the presence of an oxidizing agent for a time sufficient to obtain the desired lightening. The oxidizing agent can be added to the composition of the invention just at the time of use or it can be implemented from an oxidizing composition containing it, applied simultaneously or sequentially to the composition of the invention.

According to a particular embodiment, the composition according to the present invention comprises at least one oxidation dye precursor.

The mixture obtained is then applied to the keratinous fibers. After a pause of between 3 minutes and 1 hour and preferably between 5 and 50 minutes, the keratinous fibers are rinsed, washed with shampoo, rinsed again and then dried.

The oxidizing agents conventionally used for dyeing keratinous fibers are, for example, hydrogen peroxide, urea peroxide, alkali metal bromates, persalts such as perborates and persulfates, peracids and oxidase enzymes, among which one mention may be made of peroxidases, 2-electron oxidoreductases such as uricases and 4-electron oxygenases such as laccases. According to one particular embodiment, the composition contains a peroxide-type oxidizing agent and / or a persalt-type oxidizing agent, for example a mixture of hydrogen peroxide and persulfates, hydrogen peroxide alone or persulfate alone. The oxidizing composition may also contain various adjuvants conventionally used in compositions for dyeing hair and as defined above.

The compounds of formula (I) COL-L-COL in which the two COL chromophores are identical may in particular be prepared according to the following reaction scheme when the linker L contains a single cationic group of formula (a) to (d):

Wherein -RD-CAT-RD- represents the cationic linkage (di) L as previously defined.

According to this method, a first step of condensation of a hydrazine derivative (B) with a heteroaromatic aldehyde or ketone (A) is carried out in a manner known to those skilled in the art.

Thus, said hydrazine derivative (B) is contacted in the presence of heteroaromatic aldehyde (A).

The reaction is advantageously carried out in the presence of a catalytic amount of acid such as, for example, acetic acid, para-toluenesulphonic acid, citric acid, etc.).

Usually this reaction takes place at a temperature between 0 ° C and 100 ° C, preferably between 0 ° C and 80 ° C.

In a conventional manner, the reaction takes place in the presence of a suitable solvent, among which mention may be made of water, alcohols such as methanol or ethanol or isopropanol, dichloromethane, dimethylformamide, tetrahydrofuran, and the like. 3-dimethyl-2-oxohexahydropyrimidine, N-methylpyrrolidone, sulfolane. A precursor compound of the units of formula (Ia) to (Ig) is thus obtained. A quaternization reaction of the herocyclic nucleus is then carried out.

More particularly, this step consists in reacting the product resulting from the preceding step with a large amount (generally 5 to 10 equivalents) of a derivative having two leaving groups (denoted GP-RD-GP in the reaction scheme). By way of example, this derivative may be an optionally substituted D-dihaloalkyl such as 1,6-dibromohexane or 1,5-dichloropentane or 1,5-diiodohexane, a dialkylsulfonate or diarylsulfonate such as 4- [ (methylsulfonyl) oxy] butyl methanesulfonate or 7 - {[(4-methylphenyl) sulfonyl] oxy} heptyl 4-methylbenzene sulfonate. Usually this reaction takes place at a temperature of between 50.degree.

130 ° C, preferably between 60 ° C and 1 10 ⁰ C.

Typically, the reaction takes place in the absence or in the presence of a suitable solvent such as for example 1,2-dichloroethane, toluene, 3,4,5,6-terrahydro-2 (1H) pyrimidinone (DMPU), dimethylformamide (DMF), N-methylpyrrolidone (NMP).

The last step is a dimerization reaction of reacting the resulting product (C) (2 equivalents) in the presence of a double nucleophile and a base.

By way of example, this nucleophilic precursor of the cationic group of formula (a),

(b), (c) or (d), may be imidazole, 1- [4- (1H-imidazol-1-yl) butyl] -1H-imidazole, a secondary amine such as dimethylamine, diethylamine.

Usually this reaction takes place at a temperature between 50 ° C and 130 ° C, preferably between 60 ° C and 1 10 ⁰ C.

Typically, the reaction takes place in the presence of a suitable solvent such as, for example, dimethylformamide, butanol, 3,4,5,6-terahydro-2 (1H) -pyrimidinone (DMPU), N- methylpyrrolidone (NMP), sulfolane.

By way of example, this first method can be used for the preparation of compounds (a) to (o).

When the compounds of formula (I) COL-L-COL whose two COL chromophores are identical comprise a linker arm containing at least two cationic groups of formula (a) to (g), these compounds may be prepared according to the following protocol : COLLAR

HA: heteroaromatic ring

HA +: cationic heteroaromatic ring

wherein -RD-CAT-RD'-CAT-RD- represents the polycationic linking arm L as defined above.

According to a second embodiment, the compounds of formula (I) COL-L-COL whose two COL chromophores are different and whose linker L does not comprise a cationic group can be prepared according to the following reaction scheme:

Chromophore precursor of formula (Ia) (Ig) (E)

(

GP, GP '- departing group RD, RD' - divalent radical

Wherein -RD-CAT-RD'- represents the cationic link (di) L as defined above.

Compounds (D) and (E) are obtained in the same manner as previously described.

The compound (D) can then react in the presence of an excess (generally 5 to 10 equivalents) of a double nitrogen nucleophile. By way of example, this nucleophile may be imidazole, 1- [4- (1H-imidazol-1-yl) butyl] -1H-imidazole, a secondary amine such as dimethylamine or diethylamine.

In a conventional manner, the reaction takes place in the presence of a suitable solvent among which mention may be made of dimethylformamide, butanol, 1,3-dimethyl-2- oxohexahydropyrimidine, N-methylpyrrolidone, sulfolane, DMPU. The compound (F) is thus obtained.

The last step is a dimerization reaction of reacting the resulting product (F) in the presence of the compound (E).

In a conventional manner, the reaction takes place in the presence of a suitable solvent, among which mention may be made of dimethylformamide, butanol, DMPU, N-methylpyrrolidone and sulfolane.

By way of example, this first method can be used for the preparation of the compounds (p) to (IIe).

When the compounds of formula (I) COL-L-COL whose two COL chromophores are different comprise a linker arm L containing at least two cationic groups of formula (a) to (d), these compounds can be prepared according to the protocol next :

GP, GP 'starting group

HA1 heteroaromatic ring 1 RD, RD 'divalent radical

HA2 heteroaromatic ring 2

HA1 + cationic heteraromatic ring 1

HA2 + cationic heteraatomic nucleus 2 Wherein - RD-CAT-RD '-CAT-RD "- represents the polycationic linking arm L as defined above.

EXAMPLES

EXAMPLE 1 Synthesis of 1- (6- {dimethyl [6- (4 - {(E) - [methyl (phenyl) hydrazono] methyl} pyridinium-1-yl) hexyl] ammonio} hexyl) -4- {tribromide} (E) - [methyl (phenyl) hydrazono] methyl} pyridinium 7.

Compound 7

Step 1: synthesis of isonicotinaldehyde methyl (phenyl) hydrazone

Compound 3 Compound 4 Compound 5

In a three-neck topped with a condenser, one equivalent of N-methylphenylhydrazine (58.76 g, 0.4809 mol, compound 4) is diluted in 50 ml of ethanol and 1.5 ml of acetic acid is added. The reaction medium is then stirred at 0 ° C. Using a dropping funnel, 1 equivalent of 4-pyridinecarboxaldehyde (51.5 g, 0.4808 mol, compound 3) is added. After addition of the aldehyde, the reaction medium is heated at 65 ° C. (temperature of the oil bath) for 13 hours.

Subsequently, the reaction medium is poured into a water-ice mixture (1/3). The mixture is then placed under stirring. After stirring, the oily residue gives a yellow powder. This is then filtered and washed several times with water. After drying, 83.9 g of compound 5 are obtained. NMR spectra and mass spectra are consistent with the expected structure.

Step 2: Synthesis of 1- (6-bromohexyl) -4 - {(E) - [methyl (phenyl) hydrazono] methyl} pyridinium bromide.

compound 5 compound 6

In a 3 liter three-neck flask surmounted by a condenser, the compound 5 is diluted (80.1 g,

0.379 moles) per 250 ml of toluene. The mixture is heated to 80 ° C. and a solution of 1,6-dibromohexane (1.94 mol) in 750 ml of toluene is added over 10 minutes. A precipitate is formed during the reaction. After 4.5 hours of reaction, the reaction medium is cooled and filtered. Purification: The precipitate obtained is washed with 200 ml of toluene and then 100 ml of petroleum ether. Subsequently, this precipitate is solubilized in 1 liter of dichloromethane and then extracted with water. The organic phase is washed 4 times with water, dried over magnesium sulfate, filtered and concentrated. A brown oil is obtained which is taken up in 50 ml of toluene. A yellow precipitate is obtained which is filtered off and dried to give 95.1 g of compound 6 as a yellow powder.

NMR spectra and mass spectra are consistent with the expected structure.

Step 3: Synthesis of 1- (6- {dimethyl [6- (4 - {(E) - [methyl (phenyl) hydrazono] methyl} pyridinium-1-yl) hexyl] ammonio} hexyl) -4- {tribromide} (E) - [methyl (phenyl) hydrazono] methyl} pyridinium.

dials 7

In a three-neck topped with a condenser, is introduced the compound 6 (0.88 g, 1.93 mmol) in the presence of cesium carbonate (0.63 g, 1.93 mmol) and 10 ml of dimethylformamide. The mixture is stirred and heated at 90 ° C for 8 hours. After 8 hours of reaction, the precipitate formed is filtered off and eliminated. The filtrate is concentrated under vacuum and then purified by chromatography on silica gel (eluent EtOH / AcOH / H ₂ O: 2/1/1). Compound 7 (0.1 g) is thus obtained in the form of a yellow powder.

NMR spectra and mass spectra are consistent with the expected structure.

EXAMPLE Synthesis of 4 - {(E) - [methyl (phenyl) hydrazono] methyl} -1- (6- {1- [6- (4 - {(E) - [methyl (phenyl) hydrazono] methyl tribromide pyridinium-1-yl) hexyl] -1H-imidazol-3-ium-3-yl} hexyl) pyridinium. 8

In a three-neck topped with a condenser, is stirred and at 100 ° C for 8 hours, the compound 6 (15 g, 0.033 mol) in the presence of sodium hydrogen carbonate (1.38 g) and 1.12 g of imidazole (0.016 mol) in 300 ml of DMPU (1,3-dimethyl-3,4,5,6-tetrahydro-2 (1H) -pyrimidinone). Subsequently, the reaction medium is allowed to return to room temperature. The reaction medium is poured into 300 ml of ethyl acetate. The pasty residue obtained is separated and then taken up in an iPrOH / acetone mixture (proportion 3/7). A powder is then obtained after sonication for 2 hours. This is filtered and then dried under vacuum leading to 17.9 g of a yellow powder corresponding to the expected compound 8.

NMR spectra and mass spectra are consistent with the expected structure.

EXAMPLE Synthesis of tetrabromide of 4 - {(E) -

[methyl (phenyl) hydrazono] methyl} -1- {6- [1- (4- {1- [6- (4 - {(E) - [methyl (phenyl) hydrazono] methyl} pyridinium-1-yl) hexyl] -1H-imidazol-3-ium-3-yl} butyl) -1H-imidazol-3-ium-3-yl] hexyl} pyridinium

10

In a three-neck topped with a condenser, is stirred and at 100 ° C for 18 hours, compound 6 (20 g, 0.044 mol) in the presence of compound 9 (4.18 g, 0.0219) in 100 ml of DMPU. Subsequently, the reaction medium is allowed to return to room temperature. The reaction medium is poured into 300 ml of ethyl acetate. A pasty residue is obtained which is separated from the solvent and then taken up in isopropanol. Two phases are obtained. The alcohol phase is eliminated. The oily residue is dried under vacuum. After drying and purification by chromatography, 3.4 g of compound 10 are isolated in the form of a yellow powder.

NMR spectra and mass spectra are consistent with the expected structure.

Compound 9 can be obtained as follows:

dials 9

35.2 g of imidazole (0.52 mol), 54 g of 1,4-dibromobutane (0.26 mol), 100 g of sodium hydroxide (35 g), are stirred under reflux for 32 hours. 2.5 moles), 5.15 g of tetrabutylammonium bromide (0.016 mole) in 240 ml of toluene and 100 ml of water. After cooling, a product crystallizes. This is filtered and recrystallized from 200 ml of water. After drying under active vacuum, 48 g of a beige powder corresponding to compound 9 are obtained.

NMR spectra and mass spectra are consistent with the structure of the expected compound 9.

Examples of dyes:

The dye compositions were prepared in the following proportions: Solution 1

Solution 3: BUFFER pH 7

The staining compositions are obtained by dissolving the dye indicated below (5 × 10 ^-3 mol / l) in solution 1 and then adding an equivalent volume of buffer solution 2 or 3 (pH 7 or 9.5).

Each composition is applied to gray hair at 90% white, (1g of wick for 6g of solution). After 30 minutes break, the locks are rinsed, washed with a standard shampoo, rinsed again and then dried.

The following dyeing results were obtained

The thus colored locks are subjected to a wash resistance test, which consists of performing 10 shampoos and evaluating the color after these shampoos.

The color is evaluated by measuring L ^* a ^* b ^* in the L ^* a ^* b ^{* system} using a MINOLTA ® CM 2002 spectrophotometer (Illuminant D65). In this system L ^* a ^* b ^* , the three parameters denote respectively the intensity (L ^* ), a ^* indicates the green / red color axis and b ^* the blue / yellow color axis. The following results were obtained.

After 10 shampoos (% loss of color)

Compound I (C I Basic Yellow 87) 20-30

Compound 7 0-10

Compound 8 0-10

Compound 10 0-10

These results show that the compounds of the invention make it possible to obtain improved dyeing in terms of resistance to shampooing with respect to the composition not according to the invention containing compound I.

EXAMPLES 4

The asymmetric dichromophoric systems as defined in the invention can be obtained in parallel synthesis by reacting a halogen compound (1-X dye) with a nitrogen compound (2-imidazole dye) as shown in the reaction scheme below:

The reaction media were then purified by semi-preparative HPLC and analyzed.

1- Syntheses of halogenated compounds

Synthesis of compound [131:

Compound 4 Compound H Compound 12

8O ⁰ C

4.5 hours

Br

Compound 13

Step 1

In a three-necked flask of 25OmL equipped with a thermometer and surmounted by a condenser, 4.7 ml (40 mmol) of 1-methyl-1-phenylhydrazine are stirred at 0 ° C. (temperature of the reaction medium) [4] in 8 ml of water. 6.8 g (40 mmol) of 4-quinolinecarboxaldehyde [H] solubilized in 40 ml of methanol are then added slowly to the reaction medium, keeping it at 0 ° C. This is then slowly brought back to room temperature. The reaction is then left for 3 hours at room temperature, during which time a yellow precipitate appears.

The precipitate formed is then filtered under vacuum, washed 3 times with water and then dried under high vacuum. 10.3 g of a yellow powder corresponding to the compound [12] are obtained.

The NMR spectra and the mass spectra are in accordance with the expected product [121].

2nd step

In a 250 mL three-necked flask fitted with a thermometer and surmounted by a condenser, 1 mol of 1,6-dibromohexane is stirred at 80 ° C. in the presence of 0.5 g of compound [12]. After 4.5 hours of reaction, the dark orange reaction medium is then brought back to ambient temperature. A precipitate is formed gradually during cooling.

This is then filtered under vacuum, washed with toluene and then dried under high vacuum. 0.775 g of an orange powder corresponding to the compound [1.3] are obtained.

The NMR spectra and the mass spectra are in accordance with the expected product [131]. Synthesis of the compound H 61:

Cat.

Compound 15

Compound 14 Compound 4

AcOEt reflux, 15 h

Compound 16

Step 1

In a three-necked 25OmL equipped with a thermometer and surmounted by a condenser, stirring is carried out at 80 ° C for 12 h, 1.07 g (10 mmol) of 2-pyridinecarboxaldehyde [14], 1, 22 g. (10 mmol) of 1-methyl-1-phenylhydrazine [4] in 20 ml of ethanol in the presence of 3 drops of acetic acid.

After concentration of the reaction medium, a residue is obtained; this is neutralized to pH 8 with a saturated solution of NaHCO 3 and then extracted three times with ethyl acetate. The organic phases are combined and then dried over magnesium sulphate, filtered and evaporated to give 2 g of product [151.

The NMR spectra and the mass spectra are in accordance with the expected product [151].

Step 2 In a 250 mL three-necked flask equipped with a thermometer and surmounted by a condenser, stirring is carried out at 80 ° C. for 15 h, 2.1 g (10 mmol) of intermediate [15] and 24.4 g (100 mmol) of 1,6-dibromohexane in 15 ml of ethyl acetate. The dark yellow reaction medium is then brought back to ambient temperature. A precipitate form gradually during cooling. This is then filtered under vacuum, washed with ethyl acetate and dried. After purification on a flash silica column (methanol / dichloromethane: 1/30 to 1/10), 2.5 g of a dark yellow powder corresponding to the compound [16] are obtained.

The NMR spectra and the mass spectra are in accordance with the expected product [161].

Synthesis of the compound H 91

Compound 17 Compound 4 Compound 18 Compound 1 £

Step 1

In a 250 ml three-necked flask equipped with a thermometer and surmounted by a condenser, 4.7 ml (40 mmol) of 1-methyl-1-phenylhydrazine [4] are stirred at 0.degree. 'water. Subsequently, 6.8 g (40 mmol) of 2-quinolinecarboxaldehyde [17] solubilized in 40 ml of methanol are added slowly. The reaction medium is stirred for 3 hours at room temperature; A precipitate is formed gradually during the reaction; This is then filtered under vacuum, washed three times with water and then dried under high vacuum. 10.3 g of the compound [181 are obtained.

The NMR spectra and the mass spectra are in accordance with the expected product [181].

2nd step

In a 250 ml three-necked flask equipped with a thermometer and surmounted by a condenser, 5.22 g (20 mmol) of the intermediate [181 solubilized in 20 ml of water are stirred at 80 ° C. for 5 days. , 6-dibromohexane in the presence of a catalytic amount of KI (60 mg). After reaction, the reaction medium is cooled to room temperature. A precipitate is formed gradually during cooling. This is then filtered under vacuum, washed with ethyl acetate and dried. After purification on a flash silica column, 0.8 g of the compound [19] are obtained.

The NMR spectra and the mass spectra are in accordance with the product [191 expected. Synthesis of compound [221:

Step 1

In a 250 ml three-necked flask fitted with a thermometer and surmounted by a condenser, 2.2 g (20 mmol) of 1-methyl-2-imidazolecarboxaldehyde [20] and 2.44 are stirred at 80 ° C. g (20 mmol) of 1-methyl-1-phenylhydrazine [4] solubilized in 50 ml of ethanol in the presence of 3 drops of acetic acid. After 5 hours of reaction, the mixture is brought to ambient temperature and then concentrated; the powder obtained is cleaned with diethyl ether. After drying, 4 g of the compound [2] are obtained.

The NMR spectra and the mass spectra are in accordance with the product [2V] expected.

2nd step

In a three-necked flask of 250 ml with a thermometer and surmounted by a condenser, 1.1 g (5 mmol) of intermediate [2] and 12 ml (80 mmol) of 1 are stirred at 80 ° C. 6-dibromohexane. After heating for 5 hours, the reaction medium is cooled to room temperature. A yellow precipitate is gradually formed during cooling. This is filtered, then washed with ethyl acetate and finally dried under high vacuum to provide 2.1 g of compound [221. The NMR spectra and the mass spectra are in accordance with the expected product [22].

Synthesis of compound [251:

Step 1 In a three-neck of 25OmL equipped with a thermometer and surmounted by a condenser, stirring is carried out at 60 ° C, 2.4g (15 mmol) of 1-methyl-2-formylbenzimidazole [23] and 1, 8g (15 mmol) of 1-methyl-1-phenylhydrazine [4] solubilized in 50 ml of ethanol. After 18 hours of reaction, the reaction medium is brought to room temperature and then poured onto an ice bath; a precipitate appears. This is then filtered, then cleaned with water and finally dried. 3.9 g of the compound [24] are obtained.

The NMR spectra and the mass spectra are in accordance with the expected product [24].

2nd step

In a three-necked flask of 25OmL equipped with a thermometer and surmounted by a condenser, 3.9 g (14.7 mmol) of intermediate [24] and 23 ml (147 mmol) of 1 are stirred at 100 ° C. 6-dibromohexane. After 5 hours of reaction, the reaction medium is cooled to room temperature. A yellow precipitate is gradually formed during cooling. This is then filtered, washed several times with ethyl acetate and then dried under active vacuum. 7 g of compound [25] are obtained. The NMR spectra and the mass spectra are in accordance with the expected product [25].

2- Synthesis of nitrogen compounds

Synthesis of compound [261:

Compound 22 Compound 26

In a three-neck of 25OmL equipped with a thermometer and surmounted by a condenser, the intermediate [22] (1.83 g, 4 mmol), imidazole (2.72 g), is stirred at 80 ° C. 40 mmol), and N, N-diisopropylethylamine (DIPEA) (2.58 g, 5 mmol) solubilized in 70 ml of acetonitrile. After 6 hours of reaction, the reaction medium is brought to ambient temperature and then concentrated. The residue obtained is then dissolved in a minimum of dichloromethane. To this solution, a large amount of ethyl acetate is added until a solid precipitates. This is then filtered. This treatment is repeated 3 more times until the unreacted imidazole is removed. After purification on a column of alumina (CH ₂ Cl ₂ / MeOH = 100/8), 1.5 g of the product [26] are obtained.

The NMR spectra and the mass spectra are in accordance with the product [261 expected.

Synthesis of compound [281:

Step 1

In a three-necked flask of 25 ml with a thermometer and surmounted by a condenser, the intermediate [25] (2.03 g, 4 mmol), imidazole (2.72 g, 40 mmol) was stirred under reflux. mmol) solubilized in 30 ml of acetonitrile, then 7 ml of DIPEA and a catalytic amount of KI (67 mg, 0.4 mmol). After refluxing for 6 hours, the reaction mixture is cooled and then poured into 300 ml of ethyl acetate; a yellow solid precipitates immediately. This is then filtered, washed several times with ethyl acetate, dried under vacuum to provide 1.8 g of compound [271.

The NMR spectra and the mass spectra are in accordance with the product [271 expected.

Step 2 In a three-necked 25OmL equipped with a thermometer and surmounted by a condenser, 1.7 g of intermediate [27] solubilized in 30 ml of methanol are stirred, and 17 g of Dowex are then added. The reaction medium is stirred for 3 hours at room temperature. After filtration, 17 g of Dowex are again added to the filtrate. The suspension is stirred again for 24 hours at room temperature. After filtering and cleaning the Dowex with methanol, the resulting alcoholic solution is evaporated to dryness to yield 1.5 g of a crude product. After purification on silica gel, 0.86 g of the product [28] are obtained. The NMR spectra and the mass spectra are in accordance with the expected product [28].

Synthesis of the compound [291:

In a three-necked flask of 25OmL equipped with a thermometer and surmounted by a condenser, the intermediate [16] (2.27 g, 5 mmol), imidazole (3.40 g, 50 ml), is stirred under reflux. mmol), 30 ml of DIPEA solubilized in 30 ml of acetonitrile. After refluxing for 3 hours, the reaction mixture is cooled and concentrated; A yellowish residue is obtained. After purification on silica gel (THF / MeOH: 4/1), the product obtained (2 g) is taken up in a solvent mixture (AcOEt / MeOH: 80 ml / 2 ml) and stirred for 12 hours. The precipitate formed is then filtered and dried under active vacuum. 1.6 g of the product [29] are obtained.

The NMR spectra and the mass spectra are in accordance with the product [291 expected.

Synthesis of the compound [301:

Compound 13 Compound 30

In a three-necked flask of 25OmL equipped with a thermometer and surmounted by a condenser, the intermediate [131 (2.5 g, 5.1 mmol), imidazole (3.47 g, 51 mmol) and 8.9 ml of DIPEA (51 mmol) solubilized in 30 ml of acetonitrile. After 3 reflux times, the reaction mixture is cooled and then poured into a solution of ethyl acetate; a red solid precipitates immediately. This is then filtered and then purified on silica gel to give 1.8 g of the compound [301].

The NMR spectra and the mass spectra are in accordance with the product [301 expected.

Synthesis of the compound T311:

In a three-neck of 25OmL equipped with a thermometer and surmounted by a condenser, the intermediate [6] (2.16 g, 4 mmol), imidazole (3.12 g) is stirred at 70 ° C. 40 mmol) and 1.1 g of potassium carbonate (8 mmol) solubilized in 20 ml of acetonitrile. After 12 hours of reflux, the reaction mixture is cooled and concentrated; the residue obtained is then purified by chromatography on an alumina column. A yellow oil is obtained. This is taken up in ethyl acetate until a yellow solid precipitates. This is filtered and then dried under vacuum to provide 0.9 g of the compound [311].

The NMR spectra and the mass spectra are in accordance with the expected product [311].

Synthesis of the compound T321:

Compound 16 Compound 32

In a three-neck of 25OmL equipped with a thermometer and surmounted by a condenser, the intermediate Q61 (1.5 g, 2.7 mmol), 5.1 g of 1.4 g, is stirred at 70.degree. -bis (1-imidazolyl) butane (27 mmol) solubilized in a mixture consisting of 20 ml of acetonitrile and 5 ml of ethanol. After 12 hours of reflux, the reaction mixture is cooled and concentrated; the residue obtained is then purified by column chromatography on alumina (MeOH / CH ₂ Cl ₂ = 1/100 to 1/10) to give 1.1 g of compound [321.

The NMR spectra and the mass spectra are in accordance with the product [321 expected.

Synthesis of the compound T331:

33

In a three-necked 25OmL equipped with a thermometer and surmounted by a condenser, the intermediate [6] (1.6 g, 3 mmol), 5.7 g of 1,4-bis (1-imidazolyl) is stirred under reflux. ) butane (30 mmol) solubilized in 50 ml of acetonitrile. After 12 hours of reflux, the reaction mixture is cooled and concentrated; the residue obtained is then purified by column chromatography on alumina (MeOH / CH ₂ Cl ₂ = 1/100 to 1/10) to provide 1.05 g of compound [331.

The NMR spectra and the mass spectra are in accordance with the product [331 expected.

Synthesis of the compound T341:

In a three-necked 25OmL equipped with a thermometer and surmounted by a condenser, the intermediate [22] (1.2 g, 2.6 mmol), 5 g of 1,4-bis, is stirred under reflux. (1-imidazolyl) butane (26 mmol) solubilized in 70 ml of acetonitrile. After 6 hours of reflux, the reaction mixture is cooled and then concentrated; the residue obtained is then solubilized in water and then extracted with dichloromethane. The aqueous phase is concentrated. The powder obtained is purified by column chromatography on alumina (MeOH / CH ₂ Cl ₂ = 1/100 to 1/20) to give 1.02 g of compound [34].

The NMR spectra and the mass spectra are in accordance with the expected product [34].

Synthesis of the compound351:

MeCN, reflux, 4h

Compound 19 Compound 35

In a three-necked flask of 25OmL equipped with a thermometer and surmounted by a condenser, the intermediate [19] (1.6 g, 3.2 mmol), 6 g of 1,4-bis, is stirred under reflux. (1-imidazolyl) butane (32 mmol) solubilized in 20 ml of acetonitrile. After refluxing for 4 hours, the reaction mixture is cooled and concentrated; the residue obtained is then purified by column chromatography on alumina (MeOH / CH ₂ Cl ₂ = 1/100 to 1/10) to give 1.2 g of compound [351.

The NMR spectra and the mass spectra are in accordance with the product [351 expected.

Synthesis of compound [361:

Compound 25 Compound 36

In a three-necked flask of 25OmL equipped with a thermometer and surmounted by a condenser, the intermediate [25] (1.5 g, 3 mmol), 5.7 g of 1,4-bis, is stirred under reflux. (1-imidazolyl) butane (30 mmol) solubilized in 90 ml of acetonitrile. After 24 hours of reflux, the reaction mixture is cooled and concentrated; the resulting residue is then purified by column chromatography on alumina to give 1.1 g of compound [361.

The NMR spectra and the mass spectra are in accordance with the product [361 expected.

Synthesis of the compound T371:

Compound 13. Compound 3_7

In a three-necked flask of 25OmL equipped with a thermometer and surmounted by a condenser, the intermediate [13] (4.5 g, 9 mmol), 17 g of 1,4-bis (1 g) is stirred under reflux. imidazolyl) butane (90 mmol) solubilized in 90 ml of acetonitrile. After refluxing for 7 hours, the reaction mixture is cooled and concentrated; the resulting residue is then purified by column chromatography on alumina to give 2.5 g of compound [371.

The NMR spectra and the mass spectra are in accordance with the product [371 expected.

3- Synthesis of direct dyes and shade obtained

a) The general operating procedure for the synthesis of the direct dyes of the invention is as follows:

In a sealed 5 ml tube, the nitrogenous compound (50 mg), the halogenated compound (1.2 eq.) And 10 mg of potassium iodide are stirred in the microwave (Biotage). solubilized in 1 ml of N-methylpyrrolidone. After 1 hour at 170 ° C, the reaction mixture is cooled and then purified by preparative HPLC to provide the expected dye.

The NMR spectra and the mass spectra are in accordance with the expected product,

b) The dye compositions were prepared in the following proportions

The coloring compositions are obtained by dissolving the dye indicated below (5 × 10 ^-3 mol / l) in the above composition.

The compositions are applied to gray hair at 90% white. After 30 minutes break, the locks are rinsed, washed with a standard shampoo, rinsed again and then dried.

3-1 Synthesis from the compound T61:

Correction on the number of nitrogen compounds (9 instead of 11)

The following dyes were obtained:

-2 Synthesis from the compound [131 two

The following dyes were obtained:

3-3 Synthesis from the compound M 61:

2

The following dyes were obtained:

3-4 Synthesis from the compound H 91:

The following dyes were obtained:

3-5 Synthesis from the compound T221:

2

The following dyes were obtained: 

3-6 Synthesis from the compound [251:

The following dyes have been obtained

Claims

1. cationic dichromophoric compounds comprising two units of the hydrazone type connected by a cationic linker corresponding to the general formula (I), its resonant forms, its addition salts with an acid, its solvates:

COL -L-COL (I) in which each of the chromophores COL, identical or different, corresponds to the formulas (Ia), (Ib), (Ic), (Id), (Ie), (If) and (Ig) following

in which: the radical R ₁ represents - a hydrogen

a C 1 -C 20, preferably C 1 -C 16, saturated or unsaturated, optionally substituted alkyl radical, optionally interrupted by one or more heteroatoms and / or by one or more groups comprising at least one heteroatom, preferably chosen from oxygen, nitrogen, sulfur, CO, SO2 or combinations thereof; the alkyl radical having no nitro, nitroso, peroxo or diazo function.

an optionally substituted phenyl radical

an optionally substituted benzyl radical

an alkylcarbonyl radical (R-CO-) in which R represents a C ₁ -C ₄ alkyl radical;

an alkylsulphonyl radical (RSO 2 -) in which R represents an alkyl radical

an aminosulfonyl radical ((R) ₂ N-SO ₂ -) in which the radicals R independently of one another represent a C ₁ -C ₄ alkyl radical or an aminocarbonyl (R) ₂ N-CO- radical in which the R radicals independently of each other, represent a hydrogen atom or an alkyl radical C _r C ₄

the radical R 5 represents a C ₁ -C ₂₀ alkyl, preferably a saturated or unsaturated C ₁ -C ₆ alkyl radical, optionally substituted, optionally interrupted by one or more heteroatoms and / or by one or more groups comprising at least one heteroatom, preferably chosen; among oxygen, nitrogen, sulfur, CO, SO, SO2 or combinations thereof; the alkyl radical having no nitro, nitroso, peroxo or diazo function.

an optionally substituted phenyl radical

an optionally substituted benzyl radical

A halogen atom preferably chosen from bromine, chlorine or fluorine; . a saturated or unsaturated C ₁ -C ₆ alkyl radical, optionally substituted, optionally interrupted by one or more heteroatoms and / or by one or more groups comprising at least one heteroatom preferably chosen from oxygen, nitrogen, sulfur, CO SO, SO2 or combinations thereof; the alkyl radical having no nitro, nitroso, peroxo or diazo function. . a hydroxyl group;

• a C ₁ -C ₄ alkoxy group; a C ₂ -C ₄ (poly) hydroxyalkoxy group;

. an alkoxycarbonyl group (RO-CO-) in which R represents a C ₁ -C ₄ alkyl radical,

An alkylcarbonyloxy radical (RCO-O-) in which R represents a C ₁ -C ₄ alkyl radical; An optionally substituted aryloxy group;

. an amino group optionally substituted with one or two identical or different C ₁ -C ₄ alkyl radicals optionally carrying at least one hydroxyl or C ₁ -C ₂ alkoxy group, said alkyl radicals possibly being able to form with the nitrogen atom to which they are attached, a 5- or 7-membered, optionally substituted, optionally aromatic, saturated or unsaturated heterocycle optionally comprising another heteroatom identical to or different from the nitrogen optionally substituted with a phenyl, aminophenyl, 4-N, N- diethylaminophenylamino or methoxyphenyl.

An alkylcarbonylamino group (RCO-NR'-) in which the radical R represents a C ₁ -C ₄ alkyl radical and the radical R 'represents a hydrogen atom or a C ₁ -C ₄ alkyl radical;

An aminocarbonyl group ((R) ₂ N-CO-) in which the radicals R independently of one another represent a hydrogen atom or a C ₁ -C ₄ alkyl radical; A ureido group (N (R) ₂ -CO-NR'-) in which the radicals R and R ', independently of each other, represent a hydrogen atom or a C ₁ -C ₄ alkyl radical;

. an aminosulphonyl group ((R) ₂ N-SO ₂ -) in which the radicals R independently of one another represent a hydrogen atom or a C ₁ -C ₄ alkyl radical;

An alkylthio group (RS-) in which the group R represents a C ₁ -C ₄ alkyl radical;

. an alkylsulphonylamino group (RSO ₂ -NR'-) in which the radical R 'represents a hydrogen atom or a C ₁ -C ₄ alkyl radical, and the radical R represents a C ₁ -C ₄ alkyl radical;

• a cyano group;

. a trifluoromethyl group (CF ₃ ); . a thio radical (HS-)

An alkylsulfinyl radical (RSO-) in which the radical R represents a C ₁ -C ₄ alkyl radical;

An alkylsulphonyl radical (RSO ₂ -) in which the radical R represents a C ₁ -C ₄ alkyl radical; R 1 can also form with a group R ₂ ortho of the group NR ₁ and with the nitrogen atom substituted by R ₁ , a saturated or unsaturated heterocycle with 5 or 6 members, substituted or unsubstituted;

- Two adjacent radicals R ₂ can form between them and with the carbon atoms to which they are connected an aromatic cyclic radical or not 5 or 6-membered, substituted or unsubstituted;

- Two adjacent R3 radicals can form between them and with the carbon atoms to which they are attached, a 5- or 6-membered aromatic ring, substituted or unsubstituted;

. a hydrogen atom;

A saturated or unsaturated, optionally substituted C ₁ -C ₁₆ alkyl radical, optionally interrupted by one or more heteroatoms and / or by one or more groups comprising at least one heteroatom preferably chosen from oxygen, nitrogen, , sulfur, CO, SO, SO ₂ , or combinations thereof; the alkyl radical having no nitro, nitroso, peroxo or diazo function.

An amino group optionally substituted with one or two identical or different C ₁ -C ₄ alkyl radicals, optionally carrying at least one hydroxyl or C ₁ -C ₂ alkoxy group, said alkyl radicals possibly being able to form with nitrogen atom to which they are attached, a 5- or 6-membered saturated or unsaturated or aromatic heterocycle optionally substituted, optionally comprising at least one other heteroatom identical to or different from nitrogen; An alkylcarbonylamino group (RCO-NR'-) in which the radical R represents a C ₁ -C ₄ alkyl radical and the radical R 'represents a hydrogen atom or a C ₁ -C ₄ alkyl radical;

An alkylsulphonylamino group (RSO ₂ -NR'-) in which the radical R 'represents a hydrogen atom or a C ₁ -C ₄ alkyl radical, and the radical R represents a C ₁ -C ₄ alkyl radical; ;

An optionally substituted phenyl radical; an optionally substituted benzyl radical;

- n "is an integer between 0 and 2, when n" is less than 2, the unsubstituted carbon atom (s) carries (s) a hydrogen atom. the bond resulting from the formulas (Ia), (Ib), (Ic), (Id), (Ie), (If) and (Ig) connects each of the COL chromophores to the cationic L bonding arm of the formula (I) );

2. cationic dichromophoric compounds according to claim 1, characterized in that the radicals R 1 are identical and represent: a hydrogen atom; alkyl -C ₄ optionally substituted by one or more radicals chosen from hydroxyl, alkoxy, C ₁ -C ₂ alkyl, amino, (di) alkylamino, C ₁ -

C ₂ ; an alkylcarbonyl radical (R-CO-) in which the radical R represents a C ₁ -C ₄ alkyl radical; an aminocarbonyl group ((R) ₂ N-CO-) in which the radicals R independently of one another represent a hydrogen atom or a C ₁ -C ₄ alkyl radical; an alkylsulphonyl radical (R-SO ₂ -) in which the radical R represents a C ₁ -C ₄ alkyl radical; an optionally substituted phenyl radical; an optionally substituted benzyl radical.

3. cationic dichromophoric compounds according to claim 2, characterized in that the radicals R ₁ are identical and represent a hydrogen atom, a methyl, ethyl, 2-hydroxyethyl, 2-methoxyethyl, acetyl (CH ₃ CO-) radical, methylsulfonyl (CH ₃ SO ₂ -), phenyl, benzyl optionally substituted by one or more hydroxy, amino, or combination thereof.

4. Cationic dichromophoric compounds according to one of claims 1 to 3, characterized in that R ₁ forms with a group R ₂ ortho of the group NR ₁ and with the nitrogen atom substituted by R ₁ , a saturated heterocycle or unsaturated 5- or 6-membered ring substituted with one or more alkyl groups.

5. cationic dichromophoric compounds according to one of claims 1 to 4, characterized in that, when n, n 'or n "are different from zero, the radicals R ₂ and R ₃ represent preferably and independently one of the other:

a hydroxyl radical; a halogen atom chosen from bromine, chlorine or fluorine;

an alkyl radical in dC ₄ , optionally substituted by one or more radicals, which are identical or different, chosen from hydroxyl, C ₁ -C ₂ alkoxy and (C ₂ -C ₄ ) poly (C ₂ -C ₄ ) hydroxyalkoxy, amino, (di) alkylamino radicals; -C _2, thio (-SH), alkyl (Ci-C ₄₎ sulfinyl, (C _r -C ₄₎ alkylsulfonyl, thioalkyl (C ₄₎ - alkoxy C ₁ -C ₄ alkyl;

a (poly) -hydroxyalkoxy (C ₂ -C ₄₎ radical;

an amino radical;

a (C ₁ -C ₆ ) alkylamino radical, said alkyl radicals possibly being able to form, with the nitrogen atom to which they are attached, a saturated 5- or 7-membered heterocycle optionally comprising at least one other heteroatom which is identical to or different from the nitrogen;

a (poly) -hydroxyalkylamino (C ₂ -C ₄₎ radical;

a phenylamino radical (PhNH-), an alkoxyphenylamino radical at dC ₄ (ROPhNH-), a (di-) (alkyl) aminophenylamino radical at C ₁ -C ₄ (RR ¹ NPhNH-); a (di-) (alkyl) aminocarbonyl radical ((R) ₂ N-CO-) in which the radicals R independently of one another represent a hydrogen atom or a C ₁ -C ₄ alkyl radical;

a radical (di-) (alkyl) aminosulfonyl ((R) ₂ NSO ₂ -) in which the radicals R independently of each other represent a hydrogen atom or a C ₁ -C ₄ alkyl radical;

an alkylcarbonylamino radical (R'CONR-) in which the radical R 'represents a C ₁ -C ₄ alkyl radical and the radical R represents a hydrogen atom or a C ₁ -C ₄ alkyl radical;

an alkylthio radical (RS-) in which the radical R represents a C ₁ -C ₄ alkyl radical;

a thio radical (HS-); an alkylsulfinyl radical (RSO-) in which the radical R represents a C ₁ -C ₄ alkyl radical;

an alkylsulphonyl radical (R-SO ₂ -) in which the radical R represents a C ₁ -C ₄ alkyl radical.

6. Dichromophoric cationic compounds according to the preceding claim, characterized in that when n or n 'or n "other than zero, the radicals R ₂ and R ₃ represent and independently of one another:

a hydroxyl radical; - a chlorine atom;

a C ₁ -C ₄ alkyl radical optionally substituted by a hydroxyl, C ₁ -C ₂ alkoxy radical;

an alkoxy radical in dC ₄ ;

an amino radical; a C ₁ -C ₆ (di) alkylamino radical, said alkyl radicals possibly being able to form, with the nitrogen atom to which they are attached, a saturated 5-membered heterocycle;

- a radical alkoxyphenylamino dC ₄ (ROPhNH-), a radical (di -) (alkyl) aminophénylamino in C _r C ₄ (RR ¹ NPhNH-).

7. cationic dichromophoric compounds according to one of claims 5 or 6, characterized in that the radicals R ₂ and R ₃ independently of one another represent a chlorine atom, a methyl, ethyl, 2-hydroxyethyl, 2-methoxyethyl, methylsulfonyl (CH ₃ SO ₂ -), methylcarbonylamino (CH ₃ CONH-), hydroxyl, amino, methylamino, dimethylamino, (di) -ethylamino, (di) -2-hydroxyethylamino, methoxy, ethoxy, pyrrolidine, 4 methoxyphenylamino, 4-aminophenylamino, 4-N, N-diethylaminophenylamino.

8. Dichromophoric cationic compounds according to one of the preceding claims, characterized in that the radicals R ₄ , independently of each other, represent:

• a hydrogen atom;

. a C ₁ -C ₄ alkyl radical optionally substituted by one or more radicals chosen from hydroxyl, C ₁ -C ₂ alkoxy, (C ₂ -C ₄ ) (poly) hydroxyalkoxy, amino, (C ₁ -C ₄ ) alkylamino radicals; ₁ -C ₂ , thio (-SH), alkyl (CrC ₄ ) sulfinyl, alkyl dichloro-sulphonyl, thioalkyl (C _r C ₄ )

. an amino group optionally substituted with one or more identical or different C ₁ -C ₄ alkyl radicals, optionally carrying at least one hydroxyl group, and an alkylcarbonylamino group (RCO-NR-) in which the radicals R independently of one another others represent a C ₁ -C ₄ alkyl radical;

. an alkylsulphonylamino group (RSO ₂ -NR'-) in which the radicals R, R ', independently of one another, represent a hydrogen atom or a C ₁ -C ₄ alkyl radical;

. a phenyl radical optionally substituted by one or more radicals chosen from hydroxyl, alkoxy, C ₁ -C ₂ alkyl, (poly) hydroxyalkoxy, C ₂ -C ₄ alkyl, amino, (di) alkylamino, C _r C _2, thio ( -SH), alkyl (dC ₄ ) sulphonyl, alkylthio (C _r C ₄ );

• a benzyl radical optionally substituted by one or more radicals chosen from hydroxyl, alkoxy, -C ₂ (poly) hydroxyalkoxy, C ₂ -C ₄ alkyl, amino, (di) alkylamino, C ₁ -C ₂ alkyl, thio (- SH), alkyl K, sulfonyl, (C ₁ -C ₄ ) alkylthio.

9. Dichromophoric cationic compounds according to the preceding claim, characterized in that the radicals R _{4, which may be} identical or different, represent a hydrogen, a methyl or ethyl radical,

2-hydroxyethyl, an amino radical, a methylcarbonylamino group (CH ₃ CO-NR-); a ureido group (N (R) ₂ -CO-NR'-) in which the radical R represents a C ₁ -C ₄ alkyl radical and R 'represents a hydrogen atom or a C ₁ -C ₄ alkyl radical; a methylsulfonylamino group (CH ₃ SO ₂ -NR'-); a phenyl radical optionally substituted with at least one hydroxyl and / or amino group or combination thereof.

a benzyl radical optionally substituted by at least one hydroxyl and / or amino group or their combination.

10. Cationic dichromophoric compounds according to one of the preceding claims, characterized in that the radicals R ₅ of the same chromophore COL are identical and represent a C ₁ -C ₄ alkyl radical, optionally substituted by one or more identical radicals or not selected from hydroxy, C ₁ -C ₂ alkoxy, amino, (di) C ₁ -C ₂ alkylamino; an optionally substituted phenyl radical; an optionally substituted benzyl radical.

1. Cationic dichromophoric compounds according to the preceding claim, characterized in that the radicals R ₅ of the same chromophore COL are identical and preferably represent a methyl, ethyl, 2-hydroxyethyl, 2-methoxyethyl, phenyl or benzyl radical, optionally substituted by at least one hydroxy and / or one amino.

12. Dichromophoric cationic compounds according to one of the preceding claims, characterized in that the cationic L bonding arm connecting the two chromophores COL, represents a C ₂ -C ₄₀ alkylene radical carrying at least one cationic charge, optionally substituted and or optionally interrupted by one or more (hetero) saturated or unsaturated rings, aromatic or otherwise, identical or different, comprising from 3 to 7 members and / or optionally interrupted by one or more heteroatoms or groups comprising at least one heteroatom or their combinations ; the cationic linking arm L not comprising azo, nitro, nitroso or peroxo bonding.

13. Cationic dichromophoric compounds according to the preceding claim, characterized in that the cationic L bonding arm represents a C ₂ -C ₂₀ alkylene radical:

1- interrupted by at least one group corresponding to the formulas

In which :

. R ₉ and R _10, independently of one another, represent a C ₁ -C ₈ alkyl radical; a C ₁ -C ₆ monohydroxyalkyl radical; a C ₂ -C ₆ polyhydroxyalkyl radical; alkoxy (CrC ₆₎ alkyl C ₁ -C ₆ alkyl; an aryl radical such as optionally substituted phenyl; an arylalkyl radical such as optionally substituted benzyl; a C ₁ -C ₆ aminoalkyl radical; a C ₁ -C ₆ aminoalkyl radical, the amine of which is substituted with one or two identical or different C ₁ -C ₄ alkyl radicals; an alkyl, C, sulfonyl radical;

Two radicals Rg can together form, with the nitrogen atom to which they are attached, a saturated or unsaturated, optionally substituted, 5-, 6- or 7-membered ring;

• R _13, identical or different, represent a hydrogen atom, a halogen atom selected from bromine, chlorine or fluorine, an alkyl radical C ₁ -C ₆ monohydroxyalkyl radical, a C ₁ -C ₆ , a polyhydroxyalkyl radical in C ₂ -C _6, alkoxy C ₁ -C ₆ alkyl group, a (di) alkylamino, C ₁ -C ₄ alkyl, a hydroxycarbonyl group, an alkylcarbonyl C ₁ -C ₆ C ₁ -C ₆ thioalkyl radical, an alkyl radical, an alkyl radical, an optionally substituted benzyl radical, a radical phenyl optionally substituted with one or more radicals selected from methyl, hydroxyl, amino, methoxy;

• An is an anion or a mixture of anions, organic or mineral;

Z is an integer from 0 to 3; if z <3, then the unsubstituted carbon atoms carry a hydrogen atom;

V is an integer equal to 1 or 2, preferably 1;

And optionally interrupted by one or more heteroatoms or groups comprising at least one heteroatom or combinations thereof, such as, for example, oxygen, nitrogen, sulfur, a group -CO-, a group -SO ₂ -; provided that there is no nitro, nitroso or peroxo group or bond in the linker L;

3- and optionally substituted by one or more radicals chosen from hydroxyl, C ₁ -C ₂ alkoxy, (C ₂ -C ₄ ) (poly) hydroxyalkoxy, amino substituted by one or two linear C ₁ -C ₄ alkyl groups; ₂ optionally carrying at least one hydroxyl group.

14. cationic dichromophoric compounds according to one of the preceding claims, characterized in that they are chosen from compounds of formulas (la) to (Ig), preferably from (la) to (If) in which the linker cationic is an alkylene radical interrupted by at least one group, preferably from 1 to 3 cationic groups of formulas (a) and / or (b).

15. Cationic dichromophoric compounds according to one of the preceding claims, characterized in that they are chosen from the compounds of the following formulas, as well as their resonant forms and / or their addition salts with an acid and / or their solvates:

Year

16. Cationic dichromophoric compounds according to one of the preceding claims, characterized in that they are chosen from the following compounds:

(M)

(Ll'h)

(Ll'i)

17. A dye composition comprising in a suitable dyeing medium at least one cationic dichromophoric compound according to any one of claims 1 to 16.

18. dye composition according to claim 17 characterized in that it comprises from 0.001 to 10%, preferably from 0.01 to 10% by weight of at least one cationic dichromophoric compound relative to the total weight of the composition.

19. Dyeing composition according to any one of claims 17 or 18, characterized in that it comprises at least one additional direct dye other than the compounds of formula (I).

20. Dye composition according to any one of claims 17 to 19, characterized in that it comprises at least one oxidation dye precursor selected from oxidation bases and couplers.

21. Dye composition according to claim 20, characterized in that it comprises at least one oxidation base chosen from para-phenylenediamines, bis-phenylalkylenediamines, para-aminophenols, ortho-aminophenols, heterocyclic bases and their addition salts.

22. Dyeing composition according to claim 21, characterized in that the oxidation base (s) are present in an amount of between 0.001% to 20% by weight and preferably between 0.005% and 6% by weight relative to the total weight of the composition.

23. Dye composition according to any one of claims 17 to 22, characterized in that it comprises at least one coupler selected from meta-phenylenediamines, meta-aminophenols, meta-diphenols, naphthalenic couplers, heterocyclic couplers and their addition salts .

24. dye composition according to claim 23, characterized in that the coupler or couplers are present in an amount of between 0.001 and 20%, preferably between 0.005 and 6% by weight relative to the total weight of the composition.

25. dye composition according to any one of claims 17 to 24, characterized in that it comprises at least one hydroxylated solvent such as ethanol, propylene glycol, glycerol, polyol monoethers.

26. dye composition according to any one of claims 17 to 25 such that it comprises at least one adjuvant selected from anionic surfactants, cationic, nonionic, amphoteric, zwitterionic or mixtures thereof, anionic polymers, cationic, nonionic , amphoteric, zwitterionic or mixtures thereof, inorganic or organic thickeners, and in particular anionic, cationic, nonionic and amphoteric polymeric associative thickeners, antioxidants, penetration agents, sequestering agents, perfumes, buffers, dispersing agents, conditioning agents such as volatile or nonvolatile silicones, modified or unmodified, film-forming agents, ceramides, preserving agents, opacifying agents.

27. dye composition according to any one of claims 17 to 26, characterized in that it comprises at least one oxidizing agent selected from hydrogen peroxide, urea peroxide, alkali metal bromates, persalts, peracids and oxidase enzymes.

28. A process for dyeing keratinous fibers, as it comprises the steps of applying the dye composition according to one of claims 17 to 27 to the keratin fibers, and then allowing to pause for a sufficient period to obtain the desired coloration.

29. Use of the composition according to one of claims 17 to 27 on keratin fibers, to obtain dyes having good resistance to external agents and shampoos.