# US 4,399,303 A · Preparation and use of nitroterephthalamic acids

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- Number: US 4,399,303 A
- Document ID: US4399303A
- Status: Granted
- Kind: A
- Application number: 06/293,329
- Filed: 1981-08-17
- Granted: 1983-08-16
- Earliest claimed: 1981-08-17
- Assignees: E. I. Du Pont de Nemours and Company
- Inventors: George N. Milford, Jr.
- Web page: https://patentgrep.com/patent/US4399303A

## Abstract

2- and 3-Nitroterephthalamic acids are prepared by ammonolysis of dialkyl nitroterephthalates. The terephthalamic acids are useful as intermediates in the preparation of difunctional compounds useful in the preparation of aromatic polyamides and polybenzimidazoles.

## Claims

### Claim 1

3-nitroterephthalamic acid.