Process of the preparation of 2,5-di-phenylamino-terephthalic acid and its dialkyl esters in a high purity

US5347038A · kind A · utility

Assignee

• Hoechst GmbH · DE

Inventors

• Otto Arndt · Hofheim, DE
• Hermann Fuchs
• Walter Gilb · Hofheim, DE

Key dates

• Filing date: May 20, 1993
• Grant date: Sep 13, 1994
• Expiry date: May 20, 2013

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C07C227/08
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

An ecologically and economically improved process for the preparation of 2,5-di-phenylamino-terephthalic acid and its di-alkyl esters of the formula (1) ##STR1## in which R is a hydrogen atom or a methyl group and R' is a hydrogen atom or a methyl or ethyl group.