Process for the preparation of anthraquinone imides
US4659831A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Oct 2, 1984 |
| Grant date | Apr 21, 1987 |
| Priority date | — |
| Expiry date | Oct 2, 2004 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC09B3/10
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
The invention relates to a process for the preparation of anthraquinone imides by condensing vattable anthraquinone compounds which contain at least one primary amino group with aromatic halogen compounds, in an organic solvent and at elevated temperature in the presence of a base and a copper catalyst. The process comprises first carrying out the condensation until a reaction of 60-95% has taken place, and then subjecting the reaction mixture, without isolating the reaction product, to an aftertreatment at a temperature which is 5.degree. to 60.degree. C. above the initial temperature of the condensation. This process permits the anthraquinone imides to be obtained in increased yield and additionally provides products with improved qualities. The intermediates so obtained can be further processed to vat dyes.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.