Water → 2-AMINO-5-(AMINOSULFONYL)-4-FLUOROBENZOIC ACID

Participants

Reaction Steps

A mixture of 25.0 g (0.102 molecule) of purified sulphonamide (4), 36.7 g of magnesium sulphate heptahydrate and of 560 ml of water was stirred and heated to 80°. Potassium permanganate (48.1 g) was added, in portions, keeping the temperature between 80° and 85°. The mixture was taken to 90° during 4 hours, filtered hot and the cake, (collected into a mass), of manganese dioxide was washed with water. The filtrate was acidified with concentrated hydrochloric acid and the precipitate of compound 5 was recovered. The moist compound 5 of the above reaction and 4.0 g., previously obtained, were heated under reflux for three hours in 215 ml of 3N sodium hydroxide. The reaction mixture was filtered and the filtrate was acidified with concentrated hydrochloric acid. The separating solid was recovered on a filter, washed with water, then dried in vacuo at 80°; yield: 20.1 g (70.5%).

Provenance & Evidence