Method for producing alpha-hydroxycarboxylic acids and the esters thereof

US7423173B2 · kind B2 · utility

Assignee

• ROEHM GMBH & CO. KG · DE

Inventors

• Steffen Krill · Mühltal, DE
• Friedel Schultheis · Hasselroth, DE
• Udo Gropp · Bad Endorf, DE
• Matthias Groemping · Darmstadt, DE

Key dates

• Filing date: Jan 21, 2005
• Grant date: Sep 9, 2008
• Expiry date: Apr 4, 2025

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C07C51/377
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

The invention relates to a process for the selective, economically viable preparation of methacrylic acid and methacrylic esters starting from acetone cyanohydrin, wherein, in a first step, 2-hydroxy-2-methylpropionic acid is prepared by reacting acetone cyanohydrin with sulphuric acid in the presence of water and a suitable polar solvent and is isolated and methacrylic acid is subsequently prepared by β-elimination of water starting from 2-hydroxy-2-methylpropionic acid.