Process for preparing ketene acetals

US5455361A · kind A · utility

Assignee

• Wacker Chemie AG · DE

Inventors

• Gerald Fleischmann · Emmerting, DE
• Herbert Eck · Burghausen, DE
• Hermann Petersen · Burghausen, DE
• Siegfried Pflaum · Haag in Oberbayern, DE

Key dates

• Filing date: Sep 13, 1993
• Grant date: Oct 3, 1995
• Expiry date: Sep 13, 2013

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C07C41/50
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

The invention relates to a process for preparing ketene acetals by dehydrohalogenation of 2-haloaldehyde acetals. If the 2-haloaldehyde acetal is open chain, the dehydrohalogenation is carried out in the presence of an alkali metal hydroxide or alkaline earth metal hydroxide and a phase transfer catalyst and/or a secondary or tertiary alcohol or a secondary or tertiary diol. If the 2-haloaldehyde acetals is cyclic, the dehydrohalogenation is carried out in the presence of an alkali metal hydroxide or alkaline earth metal hydroxide and a phase transfer catalyst and with or without a secondary or tertiary alcohol or a secondary or tertiary diol, or carried out in the presence of an alkali metal hydroxide or alkaline earth metal hydroxide and a secondary or tertiary diol. The ketene acetals which can be prepared by the process of the invention serve as intermediates in organic synthesis and are suitable as monomers or comonomers in free radical polymerization for the production of biodegradable plastics.