| 摘要 |
PCT No. PCT/EP96/03960 Sec. 371 Date May 13, 1998 Sec. 102(e) Date May 13, 1998 PCT Filed Sep. 10, 1996 PCT Pub. No. WO97/10237 PCT Pub. Date Mar. 20, 1997Compounds of the formula (I): wherein R1, R2, R3 and R4 independently of one another may represent a hydrogen atom, a (C1-4) alkyl group, a hydroxy (C2-3) alkyl group, an alkoxy (C2-3) alkyl group, an amino (C2-3) alkyl group or a 2,3-dihydroxypropyl group and R5 and R6 independently of one another may represent hydrogen or a (C1-4) 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. |
