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AssigneeHans Schwarzkopf GmbH
InventorsMustafa Akram, Wolfgang Bauer, Andreas Bittner, Astrid Kleen
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Compounds of the formula (I): ##STR1## wherein R.sub.1, R.sub.2, R.sub.3 and R.sub.4 independently of one another may represent a hydrogen atom, a (C.sub.1-4) alkyl group, a hydroxy (C.sub.2-3) alkyl group, an alkoxy (C.sub.2-3) alkyl group, an amino (C.sub.2-3) alkyl group or a 2,3-dihydroxypropyl group and R.sub.5 and R.sub.6 independently of one another may represent hydrogen or a (C.sub.1-4) alkyl group, are made by reacting 2,4-dinitrohalobenzenes with 4-hydroxymethyl-1,3-dioxolanes under alkaline conditions to form 4-(2,4-dinitrophenoxymethyl)-1,3-dioxolanes, which are further reduced to the compounds of formula (I). In an alternate process, the 4-hydroxymethyl-1,3-dioxolanes are reacted with 4-halo-3-nitranilines or 2-halo-5-nitranilines, the product further reacted first under basic conditions with chloroformic acid ester followed by treatment with strong base, alkylation or alkoxylation, reduction, and optionally further alkylation of alkoxylation to arrive at the compounds (I). The compounds are useful as secondary intermediates in oxidative dyeing of keratinous fibers, particularly hair, and can be incorporated into compositions of various forms suitable for dyeing such fibers.
A compound of the formula (I):
A process for the production of a compound of the formula (I):
A process for the production of a compound of formula (I):
A hair colorant comprising an effective amount of a secondary intermediate compound of formula (I):
A hair colorant comprising an effective amount of a secondary intermediate compound of formula (I):
Dependencies are inferred from the claim text.