3,4,5,6-Tetrahydrophthalic anhydride → 1-[2-Chloro-4-fluoro-5-(1,2,3,4,5,6-hexahydro-1,3-dioxo-isoindolyl)-phenylthio]-cyclopropanecarboxylic acid

Participants

Reaction Steps

A mixture of 2.4 g of 1-(5-amino-2-chloro-4-fluoro-phenylthio)-cyclopropanecarboxylic acid, 1.5 g of 3,4,5,6-tetrahydrophthalic anhydride and 100 ml of glacial acetic acid is heated under reflux for 18 hours while stirring. The reaction mixture is then introduced into ice-water and the resulting product is extracted with ethyl acetate. Drying over sodium sulfate and concentration of the solution by evaporation yield 1.7 g of 1-[2-chloro-4-fluoro-5-(1,2,3,4,5,6-hexahydro-1,3-dioxo-isoindolyl)-phenylthio]-cyclopropanecarboxylic acid having a melting point of from +186° to +188° C.

Provenance & Evidence