Preparation of 1-amino-4-hydroxy-2-(6'-hydroxyhexoxy)-anthraquinone
US4916244A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Aug 10, 1988 |
| Grant date | Apr 10, 1990 |
| Priority date | — |
| Expiry date | Aug 10, 2008 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC09B1/503
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
1-Amino-2-(6'-hydroxyhexoxy)-4-hydroxyanthraquinone (I) is prepared from the corresponding 2-phenoxy- or 2-halo-anthraquinone compound and 1,6-hexanediol with or without a phenol in the presence of an alkaline agent at elevated temperatures by reacting, per mole of the anthraquinone compound, from 2 to 6 moles of 1,6-hexanediol in the presence of ethylene oxide adducts on phenols or alkanols and/or polyethylene glycols at from 125.degree. to 135.degree. C. and then heating the resulting reaction mixture at from 140.degree. to 150.degree. C., in the course of which the stage 1 byproducts, namely the 1',6'-bis(1-amino-4-hydroxyanthraquinonyloxy)hexane diether is cleaved into (I), leaving a diether level of .ltoreq.2% by weight in (I).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.