Production of high-quality aromatic amino azo compounds by the rearrangement of 1,3-diaryl triazenes
US4279815A · kind A · utility
1Cited by
7References
10Claims
0Family size
Inventor
Key dates
| Filing date | Jan 9, 1979 |
| Grant date | Jul 21, 1981 |
| Priority date | — |
| Expiry date | Jan 9, 1999 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07C245/24
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
A 1,3-diaryl triazene, in a solution obtained by the diazotization-coupling of a primary aromatic monoamine with a gas containing NO and NO.sub.2, which solution contains the monoamine and up to about 30 percent by weight of the triazene, based on the weight of the solution, is contacted with 0.4-2.0 percent of a strong acid, preferably nitric acid (based on the weight of the triazene-containing solution), at 50.degree.-120.degree. C. The triazene rearranges to an aromatic amino azo compound in a high para/ortho isomer ratio with minimum formation of binuclear by-products.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.