Process for the preparation of thiochloroformates

US4340746A · kind A · utility

Assignee

• Hoechst GmbH · DE

Inventors

• Gunther Semler · Kelkheim, DE
• Georg Schaeffer

Key dates

• Filing date: Aug 26, 1980
• Grant date: Jul 20, 1982
• Expiry date: Aug 26, 2000

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C07C329/00
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

Thiochloroformates are prepared by reaction of mercaptans with phosgene in the presence of carboxylic acid amides and/or urea derivatives as catalysts in amounts smaller than hitherto known for this application. The amounts range from about 0.02 to 0.2 mol %, relative to the corresponding starting mercaptan. Despite the small amounts of catalyst the reaction proceeds as with the use of larger catalyst amounts; however, work-up is simplified and the product yields are increased in most cases.