Preparation of 4,6-diaminoresorcinol through a bisazoarylresorcinol intermediate
US5453542A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 24, 1994 |
| Grant date | Sep 26, 1995 |
| Priority date | — |
| Expiry date | Feb 24, 2014 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07C245/08
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
The present invention is a method of preparing a 4,6-bisarylazoresorcinol comprising reacting an aryldiazonium salt and resorcinol in the presence of a base and a reaction medium containing water and a water-miscible solvent at a temperature in the range of about -5.degree. C to about -60.degree. C. The present invention is also a method of preparing a 2-substituted 4,6-bisarylazoresorcinol comprising reacting an aryldiazonium salt with a 2-substituted resorcinol. The 4,6-bisarylazoresorcinol or 2-substituted 4,6-bisarylazoresorcinol can then be hydrogenated to a 4,6-diaminoresorcinol, which is a precursor to polybisbenzoxazoles (PBOs), polymers which are useful as insulators, solar arrays, and tear-resistant gloves.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.