Process for chemical synthesis from an alkenone made from a halogenated precursor

US8957254B2 · kind B2 · utility

Assignee

• SOLVAY SA · BE

Inventors

• Max Braun · Großburgwedel, DE
• Stefan Palsherm · Barsinghausen, DE
• Uta Claassen · Hohenhameln, DE
• Alain Lambert · Beauvechain, BE

Key dates

• Filing date: Oct 4, 2013
• Grant date: Feb 17, 2015
• Expiry date: Oct 4, 2033

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C07C45/65
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

Process for synthesizing a chemical, in particular an agriculturally or pharmaceutically active compound, including: a first step comprising reacting a carboxylic acid halide with a vinyl ether to prepare a halogenated precursor of an alkenone; a second step comprising eliminating hydrogen halide from such precursor to form an alkenone, preferably by thermolysis under specific conditions; and a third step which uses the formed alkenone as a building block to synthesize the chemical. First step may be done in a liquid reaction medium comprising an alkenone or a halogenated alkenone precursor, or in a liquid reaction medium in turbulent state, specifically by creation of gas bubbles of the carboxylic acid halide herein. Second step may include a flash thermolysis, vacuum thermolysis, thermolysis under stripping with inert gas, and/or a thermolysis at a temperature from >90° C. to 120° C. Third step preferably comprises reacting the alkenone with a nitrogen-containing compound.