Process for the preparation of poly(fluoroalkyl)acetophenones

US6410796B1 · kind B1 · utility

Assignee

• BAYER HEALTHCARE LLC · DE

Inventors

• Wulf Kuhnle · Neunburg vorm Wald, DE
• Thomas Hopfner · Recklinghausen, DE

Key dates

• Filing date: Dec 8, 2000
• Grant date: Jun 25, 2002
• Expiry date: Dec 8, 2020

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C07C45/00
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

Acetophenones which are di- or polysubstituted by fluoroalkyl groups on the aromatic ring are prepared in a particularly advantageous manner from the corresponding fluoroalkylanilines and acetaldoxime by preparing a corresponding diazonium salt mixture from the fluoroalkylaniline, reacting this mixture with acetaldoxime in the presence of at least one copper and/or palladium compound, without adding buffer salts or a reducing agent, carrying out the reaction with acetaldoxime at 5 to 50° C. and in the presence of halide ions and at least one strong acid that is not a hydrohalic acid, and finally heating the mixture to a temperature in the range 70 to 160° C.