反应详情

To the solution of 4-(2-ethoxycarbonyl-2-methanesulfonyl-vinylamino)-benzoic acid ethyl ester (example 61d) in phosphorous oxychloride (700 mL), Polyphosphoric acid (PPA, 445 g) was added. The resulted mixture was heated at 70 degrees for 8 hours under mechanical stirring. After the reaction, the reaction mixture was cooled to room temperature, and then phosphorous oxychloride was evaporated under reduced pressure. To the residue, water was added. The solid was filtered, collected, washed with water thoroughly, and then dried. Column chromatography gave 4-hydroxy-3-methanesulfonyl-quinoline-6-carboxylic acid ethyl ester (25 g, purity 70%). LC-MS m/e 232 (MH+)

1. temperatureThe resulted mixture was heated at 70 degrees for 8 hours under mechanical stirring
2. customAfter the reaction
3. customphosphorous oxychloride was evaporated under reduced pressure
4. additionTo the residue, water was added
5. filtrationThe solid was filtered
6. customcollected
7. washwashed with water thoroughly
8. customdried