Composition for dyeing keratin fibers which contain at least one diaminopyrazole, dyeing process, novel diaminopyrazoles and process for their preparation

Claim 1

A composition for the oxidation dyeing of keratin fibers, comprising, in a medium which is suitable for dyeing, at least one coupler and at least one oxidation base, wherein said at least one oxidation base is selected from a 3-substituted 4,5-diaminopyrazole of the following formula (I) and an acid-addition salt thereof: ##STR18## in which: R 1 , R 2 , R 3 , R 4 and R 5 which may be identical or different, represent a hydrogen atom; a linear or branched C 1 -C 6 alkyl radical; a C 2 -C 4 hydroxyalkyl radical; a C 2 -C 4 or a C 1 -C 4 alkyl, C 1 -C 4 alkoxy, nitro, trifluoromethyl, amino or C 1 -C 4 alkylamino radical; a benzyl radical; a benzyl radical substituted with a halogen atom or with a C 1 -C 4 alkyl, C 1 -C 4 alkoxy, methylenedioxy or amino radical; or a radical ##STR19## in which m and n are integers, which may be identical or different, from 1 to 3 inclusive, X represents an oxygen atom or an NH group, Y represents a hydrogen atom or a methyl radical and Z represents a methyl radical, a group OR or NRR' in which R and R', which may be identical or different, denote a hydrogen atom, a methyl radical or an ethyl radical, it being understood that when R 2 represents a hydrogen atom, R 3 may then also represent an amino or C 1 -C 4 alkylamino radical, R 6 represents a linear or branched C 1 -C 6 alkyl radical; a C 1 -C 4 hydroxyalkyl radical; a C 1 -C 4 aminoalkyl radical; a C 1 -C 4 dialkylamino (C 1 -C 4 ) alkyl radical; a C,-C 4 alkylamino (C 1 -C 4 ) alkyl radical; a C 1 -C 4 hydroxyalkylamino (C 1 -C 4 ) alkyl radical; a C 1 -C 4 alkoxymethyl radical; a phenyl radical; a phenyl radical substituted with a halogen atom or with a C 1 -C 4 alkyl, C 1 -C 4 alkoxy, nitro, trifluoromethyl, amino or C 1 -C 4 alkylamino radical; a benzyl radical; a benzyl radical substituted with a halogen atom or with a C 1 -C 4 alkyl, C 1 -C 4 alkoxy, nitro, trifluoromethyl, amino or C 1 -C 4 alkylamino radical; a heterocycle which is thiophene, furan or pyridine, or alternatively a radical --(CH 2 ) p --O--(CH 2 ) q --OR", in which p and q are integers, which may be identical or different, from 1 to 3 inclusive and R" represents a hydrogen atom or a methyl radical, wherein said at least one oxidation base is present in an amount effective to dye said keratin fibers, it being understood that, in the above formula (I): at least one of the radicals R 2 , R 3 , R 4 and R 5 represents a hydrogen atom, when R 2 , or respectively R 4 , represents a substituted or unsubstituted phenyl radical or a benzyl radical or a radical ##STR20## R 3 , or respectively R 5 , cannot then represent any of these three radicals, when R 4 and R 5 simultaneously represent a hydrogen atom, R 1 can then form, with R 2 and R 3 , a hexahydropyrimidine or tetrahydroimidazole heterocycle optionally substituted with a C 1 -C 4 alkyl or 1,2,4-tetrazole radical, when R 2 , R 3 , R 4 and R 5 represent a hydrogen atom or a C 1 -C 6 alkyl radical, R 1 or R 6 may then also represent a 2-, 3- or 4-pyridyl, 2- or 3-thienyl or 2- or 3-furyl heterocyclic residue optionally substituted with a methyl radical or alternatively a cyclohexyl radical.