Sulfuric Acid → 3-(4-Bromo-2-fluorophenyl)-2-propenoic acid

Participants

Reaction Conditions

Reaction Steps

62 ml of sulfuric acid were added to 236 ml of water and the mixture was cooled to 5° C. 57.0 g of 4-bromo-2-fluoroaniline were added at this temperature and a solution of 24.2 g of sodium nitrite in 45 ml of water was added dropwise at 0 to 2° C. in the course of 30 minutes and the mixture was stirred for 20 minutes. 2.8 g of amidosulfonic acid were then added. 5 ml of the diazonium salt solution were added dropwise at 40° C. to 27.5 g of acrylic acid, 0.23 g of palladium(II) acetylacetonate was added and the residual diazonium salt solution was added dropwise in the course of 20 minutes. The mixture was stirred at 40° C. for 4 hours. It was allowed to cool to room temperature and the product was isolated by filtration. After drying, 54.4 g of 4-bromo-2-fluorocinnamic acid were present (74% of theory; melting point: 218° C.).

Provenance & Evidence