Process for the manufacture of nitroaminopyridines
US4091025A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 7, 1976 |
| Grant date | May 23, 1978 |
| Priority date | — |
| Expiry date | Oct 7, 1996 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07D213/61
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
A process for the manufacture of 2,4,6-triamino-5-nitro-pyridines of the general formula ##STR1## wherein each of R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.5 and R.sub.6 represents a hydrogen atom, a substituted or unsubstituted aryl, aralkyl or cycloalkyl group or an aliphatic group, and R.sub.1 and R.sub.2, R.sub.3 and R.sub.4, and R.sub.5 and R.sub.6 together can form a ring which contains the amino-nitrogen, which process comprises PA1 (a) aminating a 2-halogeno-3-cyano-4,6-diaminopyridine, preferably 2-bromo-3-cyano-4,6-diamino-pyridine either to give the triaminopyridine of the formula ##STR2## wherein R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.5 and R.sub.6 are as defined above, and then treating this product initially with nitrating agents and subsequently saponifying the cyano group until decarboxylation has been effected, or PA1 (b) treating it with nitrating agents and aminating the 2-halogen atom, namely the 2-bromine atom, in the resultant 5-nitro product and subsequently saponifying the cyano group until decarboxylation has been effected. The nitropyridines obtained are valuable coupling components for the synthesis of azo dyestuffs.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.