Process for the preparation of 4,4′-dihalogen-o-hydroxydiphenyl compounds

US6596907B1 · kind B1 · utility

Assignee

• Ciba Specialty Chemicals Corporation · US

Inventors

• Armando Di Teodoro · Rheinfelden (Baden), DE
• Werner Hölzl · Eschentzwiller, FR
• Dieter Reinehr · Kandern, DE
• Rudolf Zink · Therwil, CH

Key dates

• Filing date: Apr 3, 2001
• Grant date: Jul 22, 2003
• Expiry date: Apr 3, 2021

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C07C41/26
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

A description is given of a three-step process for the preparation of 4,4′-dihalogen-o-hydroxydiphenyl compounds of formula (1) which comprises: a) hologenating an alkoxyphenol of formula (6) (=a1), reacting the resulting halogenated phenol compound of formula (5) with p-dihalobenzene of formula (4a) in the presence of copper and/or copper salts to the diphenyl ether compound of formula (2) (=a2) and subsequent ether fission to the diphenyl ether compound of formula (1) (=a3); or b) reacting an alkoxyphenol of formula (6) with the halophenol of formula (4b) to the compound of formula (3) (=b1), then halogenating this compound (=b2) and subsequent ether fission of the resulting compound of formula (2) to the diphenyl ether compound of formula (1) (=b3). The compounds of formula (1) are used for protecting organic materials and objects against microorganisms.