Process for the preparation of 1,1-difluoroalkanesulphenyl chlorides

US5223643A · kind A · utility

Assignee

• BAYER HEALTHCARE LLC · DE

Inventors

• Stefan Bohm · Cologne, DE
• Albrecht Marhold · Leverkusen, DE
• Dietmar Bielefeldt · Ratingen, DE

Key dates

• Filing date: Nov 7, 1991
• Grant date: Jun 29, 1993
• Expiry date: Nov 7, 2011

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C07C313/08
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

The present invention relates to a multi-step process for the preparation of 1,1-difluoroalkanesulphenyl chlorides of the general formula (I): EQU R--CH.sub.2 --CF.sub.2 --S--Cl The process comprises the following steps: PA1 (1) R.sup.1 --SH+R--CH.dbd.CF.sub.2 .fwdarw.R.sup.1 --S--CF.sub.2 --CH.sub.2 --R PA1 (2) R.sup.1 --S--CF.sub.2 --CH.sub.2 --R+chlorine agent.fwdarw.Cl--S--CF.sub.2 --CH.sub.2 --R Step (1) is carried out in a base at 0.degree. C.-250.degree. C., optionally in the presence of a solvent and/or a phase transfer catalyst. Step (2) is carried out at -78.degree. C.-100.degree. C., optionally in a solvent and optionally after the product of step (1) has been isolated. The final products are intermediates for organic syntheses.