Process for preparing 1-substituted 5-hydroxy-imidazoline-2,4-diones and 1-substituted 5-alkoxy-imidazoline-2,4-diones

US6365752B1 · kind B1 · utility

Assignee

• BAYER HEALTHCARE LLC · DE

Inventors

• Witold Broda · Neunkirchen, DE
• Luc Vanmaele · Lochristi, BE

Key dates

• Filing date: Jul 18, 2000
• Grant date: Apr 2, 2002
• Expiry date: Jul 18, 2020

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C07D233/66
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

A process for preparing specific 1-substituted 5-hydroxy-imidazoline-2,4-diones by reacting glyoxylic acid with N-substituted ureas is provided, where this process is carried out in a 10-80% strength aqueous solution and in the presence of an acid catalyst. The 1-substituted 5-hydroxy-imidazoline-2,4-diones can subsequently be converted in a further reaction step to give 1-substituted 5-alkoxy-imidazoline-2,4-diones.