Process for the preparation of aromatic or heteroaromatic sulphonyl chlorides

US6365780B1 · kind B1 · utility

Assignee

• BAYER HEALTHCARE LLC · DE

Inventors

• Albert Schnatterer · Leverkusen, DE
• Monika Hermann · Rösrath, DE

Key dates

• Filing date: Aug 27, 1999
• Grant date: Apr 2, 2002
• Expiry date: Aug 27, 2019

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C07C303/02
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

Aromatic or heteroaromatic sulphonyl chlorides of the general formula I in whichX may be a C or N,R1 may be fluorine, chlorine, bromine, nitro, methoxy, fluoromethoxy, difluoromethoxy, trifluoromethoxy, C1-C4 alkyl or phenyl,R2 may be H, fluorine, chlorine, bromine, OH, C1-C4 alkyl, are prepared by diazotization of the compounds of the general formula II in whichX, R1 and R2 are as defined for formula (I), and decomposition of the resulting diazonium salts in the presence of sulphur dioxide and a copper catalyst, where the compounds of the formula (II) are treated, in a mixture with one or more organic solvents, sulphur dioxide and a copper catalyst, with hydrogen chloride and alkyl nitrite at temperatures of from −20 to +60° C.