1,1'-Carbonyldiimidazole → N-[3-Fluoro-4-(phenylsulfonyl)phenyl]-3,3,3-trifluoro-2-hydroxy-2-trifluoromethylpropanamide

Participants

Reaction Conditions

Reaction Steps

To a solution of 3,3,3-trifluoro-2-hydroxy-2-trifluoromethylpropanoic acid (1.26 g, 5.9 mmol) in dry tetrahydrofuran (35 mL) was added 1,1'-carbonyldiimidazole (0.89 g, 5.5 mmol). The mixture was heated to 45° C. in an ultrasound bath for 30 minutes, then 3-fluoro-4-phenylsulfonylbenzeneamine (1.35 g, 5.4 mmol) was added in one portion. The reaction mixture was heated at 65° C. in the ultrasound bath for 30 hours. Tetrahydrofuran was removed from the reaction mixture in vacuo, and the residue partitioned between water and ethyl ether. The aqueous layer was extracted with ethyl ether (2×50 mL), and the combined ether portions were dried (MgSO4 and concentrated in vacuo to an off-white solid. The solid was dissolved in ethyl ether, treated with HCl/ethyl ether and filtered to remove unreacted 3-fluoro-4-phenylsulfonylbenzeneamine. The filtrate was concentrated in vacuo, and the resulting solid recrystallized from ethyl ether/hexane to yield the title propanamide as a white solid (0.32 g, 13%); mp 188°-189° C. 1H--NMR (250 MHz, d6 --DMSO): 7.62-7.84 (m, 4H, aromatic) 7.91-7.94 (m, 3H, aromatic) 8.03-8.09 (m, 2H, aromatic) 9.60 (s, 1H, NH). MS (CI, CH4): 446 (M+1).

Provenance & Evidence