Hydrochloric Acid → 2-Hydroxy-5-[2-[4-[(2-pyridinylamino)sulfonyl]phenyl]ethenyl]benzoic acid

Participants

Reaction Conditions

Reaction Steps

Methyl 2-hydroxy-5-[2-[4-[(2-pyridinylamino)sulfonyl]phenyl]ethenyl]benzoate (12 g, 29 mmol) was dissolved in 1M KOH (120 ml) and the solution was refluxed for 7 h. The cooled solution was acidified with an excess of 1M hydrochloric acid. The precipitate was filtered off and washed with water (3×200 ml). The product was redissolved in a small portion of 1M NaOH. Water and dioxane (500+500 ml) was added and the solution was heated to 100° C. The solution was acidified with an excess of 1M HCl, and the product precipitated upon cooling. Yield 9 g (75%).

Provenance & Evidence