Process for the preparation of o-hydroxy-benzaldehydes

US5130493A · kind A · utility

Assignee

• BAYER HEALTHCARE LLC · DE

Inventors

• Albert Schnatterer · Leverkusen, DE
• Helmut Fiege · Leverkusen, DE
• Karl H. Neumann · Sankt Augustin, DE

Key dates

• Filing date: Apr 5, 1991
• Grant date: Jul 14, 1992
• Expiry date: Apr 5, 2011

Classification

• Technology area (CPC B): Performing Operations; Transporting
• CPC primary: B01J2531/842
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

o-Hydroxy-benzaldehydes can be obtained by oxidation of the o-cresols, on which they are based, with oxygen in the presence of substances having a base reaction in a solvent if chelate complexes of iron, manganese or a mixuture of both with polyaza-macrocycles as chelating agents are employed as catalysts. Copper or a copper compound is advantageously added as a co-catalyst.