Manufacture of 2-hydroxy-naphthalene-3-carboxylic acid
US4002675A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 6, 1975 |
| Grant date | Jan 11, 1977 |
| Priority date | — |
| Expiry date | Feb 6, 1995 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07C51/15
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
A process for the manufacture of 2-hydroxy-naphthalene-3-carboxylic acid by heating sodium .beta.-naphtholate or a mixture of potassium .beta.-naphtholate and sodium .beta.-naphtholate with nitrogen compounds and/or polyphosphates containing at least 3 phosphorus atoms per molecule to a temperature of at least 180.degree. C, reaction with carbon dioxide and subsequent reaction of the resulting salt with acid. The 2-hydroxy-naphthalene-3-carboxylic acid obtainable by the process of the invention is a starting material for the manufacture of dyes, a coupling component for dye lakes and for chrome dyes, and a developer for diazotizable dyes.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.