合成路线1

Finally, etoricoxib is obtained by several related ways: Cyclization of ketosulfone (XXIV) with 2-chloromalondialdehyde (XXIX) or the aniline derivative (XXX) and ammonium acetate in hot propionic acid. Cyclization of ketosulfone (XXIV) with aminoacrolein (XXXI) in the absence of ammonium acetate. Aminoacrolein (XXXI) is prepared by treatment of chloromalondialdehyde (XXIX) with isopropanol, yielding the ether (XXXII) and followed by reaction with ammoniun hydroxide. Cyclization of the lithium enolate of ketosulfone (XXIV) with 2,3-dichloroacrolein (XXXIII) -- obtained by treatment of chloromalondialdehyde (XXIX) with oxalyl chloride and DMF in toluene -- followed by reaction with ammonium acetate or anhydrous ammonia. Reaction of ketosulfone (XXIV) with 2-chloro-1,3-bis(dimethylamino)trimethinium hexaflourophosphate salt (XXXIV) in the presence of an equimolar amount of t-BuOK followed by treatment with HOAc/TFA and then heating at reflux with an excess of ammonium hydroxide. 2-Chloro-1,3-bis(dimethylamino)trimethinium hexaflourophosphate salt (XXXIV) is obtained by reaction of chloroacetic acid (XXXV) with hot dimethylformamide (XXXVI) and POCl3, and then the reaction mixture is treated with 5N NaOH and hexafluorophosphoric acid in water.