Process for the manufacture of aromatic sulphonic acid esters of aromatic amino-hydroxy compounds

US4158670A · kind A · utility

Assignee

• Cassella Aktiengesellschaft · DE

Inventors

• Rolf Muller · Karben, DE
• Joachim Ribka · Offenbach am Main, DE
• Horst Tappe · Dietzenbach, DE

Key dates

• Filing date: Feb 22, 1978
• Grant date: Jun 19, 1979
• Expiry date: Feb 22, 1998

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C07C303/28
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

A process for the manufacture of esters of aromatic sulphonic acids and aromatic aminohydroxy compounds, of the formula I EQU h.sub.2 n--a--o--so.sub.2 --b (i) comprising reacting an aromatic aminohydroxy compound of the formula II EQU h.sub.2 n--a--oh (ii) having a pK.sub.a value of from 8.5 to 10.1, with a sulphochloride of the formula III EQU cl--SO.sub.2 --B (III) wherein PA1 A is phenylene, substituted phenylene, naphthylene or substituted naphthylene, PA1 B is phenyl, substituted phenyl, naphthyl or substituted naphthyl, and both A and B are free from --COOH and --SO.sub.3 H substituents; PA1 The reaction taking place in a reaction medium consisting essentially of water and a water-immiscible organic solvent for the sulphochloride, PA1 At a temperature of from 0.degree. to 95.degree. C., at a pH which is determined from and associated with the pK.sub.a value of said aromatic aminohydroxy compound of formula II by the equation EQU pK.sub.a -pH=0.5 to -1.5, PA1 and in the presence of a phase transfer catalyst.