Process for the preparation of 3-substituted 4-cyano-pyrrole compounds

US5258526A · kind A · utility

Assignee

• BAYER HEALTHCARE LLC · DE

Inventors

• Peter C. Knuppel · Wermelskirchen, DE
• Reinhard Lantzsch · Leverkusen, DE
• Klaus Jelich · Wuppertal, DE
• Peter Andres · Ginsheim-Gustavsburg, DE
• Albrecht Marhold · Leverkusen, DE

Key dates

• Filing date: Feb 28, 1992
• Grant date: Nov 2, 1993
• Expiry date: Feb 28, 2012

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C07D207/34
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

A process for the preparation of 3-substituted 4-cyanopyrrole compounds of the formula (I) ##STR1## in which Ar has the meaning given in the description, by reaction in a 1st stage of bromides (II) EQU Ar--Br (II) with acrylonitrile in the presence of a solvent and a suitable reaction auxiliary to give acrylonitrile derivatives (III) EQU Ar--CH.dbd.CH--CN (III) and in a 2nd stage with a phenylsulphonylmethyl isocyanide (IV) EQU Ph--SO.sub.2 --CH.sub.2 --CN (IV) in the presence of a solvent and optionally in the presence of a suitable reaction auxiliary, characterised in that the 1st stage is carried out in the presence of a palladium catalyst and the 2nd stage in the presence of a 1.2- to 1.8-fold molar excess of alkali metal alcoholate or alkali metal hydroxide.