Method for producing 2,3,5,6-tetrahalogen-xylyidene compounds

US6753444B2 · kind B2 · utility

Assignee

• BAYER HEALTHCARE LLC · DE

Inventors

• Reinhard Langer · Krefeld, DE
• Lars Rodefeld · Leverkusen, DE

Key dates

• Filing date: Jul 24, 2002
• Grant date: Jun 22, 2004
• Expiry date: Jul 24, 2022

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C07C17/093
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

The invention relates to a process for preparing 2,3,5,6-tetrahaloxylylidene compounds of formula (I) where each Hal is independently fluorine or chlorine, and X is fluorine, chlorine, bromine, —O—R, or —O—C(═O)R, where R is hydrogen, a straight-chain or branched C1-C12-alkyl- or a C6-C14-aryl radical, by reacting 2,3,5,6-tetrahaloxylylidenediamines of formula (II) with an alkyl nitrite and/or nitrous acid in HX as a solvent.