Process for the preparation of pyridine-4-aldehyde phenylhydrazones

US4310664A · kind A · utility

Assignee

• BAYER HEALTHCARE LLC · DE

Inventors

• Heinz Giesecke · Leverkusen, DE
• Alfred Brack · Odenthal, DE

Key dates

• Filing date: Jun 26, 1980
• Grant date: Jan 12, 1982
• Expiry date: Jun 26, 2000

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C07D213/53
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

Pyridine-4-aldehyde phenylhydrazones are prepared by catalytic hydrogenation of 4-cyano-pyridine under normal pressure or almost normal pressure in the presence of phenylhydrazine or nuclear-substitution products thereof, in an aqueous medium in the absence of organic solvents, at a pH value between 9 and 12, preferably between 9.5 and 11, and in a temperature range from 0.degree. to 60.degree. C.