Process for making 4-chloro-2-methyl-5-nitro-phenol

US4960955A · kind A · utility

Assignee

• Wella GmbH · DE

Inventors

• Thomas Clausen · Alsbach, DE
• David Rose · San Diego, US

Key dates

• Filing date: May 17, 1989
• Grant date: Oct 2, 1990
• Expiry date: May 17, 2009

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C07C201/16
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

The process of making 4-chloro-2-methyl-5-nitro phenol (I) ##STR1## comprises nitrating a 4-chloro-2-methyl-phenyl sulfonate of the formula (II) at the 5 position ##STR2## in which R is a residue selected from the group consisting of methyl-, ethyl-, trifluoromethyl-, phenyl- and tolyl and the sulfonyl residue comprises --SO.sub.2 R at the position 5 to form 4-chloro-2-methyl-5-nitro-phenyl-sulfonate and then cleaving the sulfonyl residue of the 4-chloro-2-methyl-5-nitro-phenyl-sulfonate to form the 4-chloro-2-methyl-5-nitro-phenyl. The process uses technically available and economical starting materials and allows an isomerically pure product to be made in very good yield.