反应详情

A solution of N-(4-chloro-2-formylphenyl)trifluoromethanesulfonamide 24 (180 mg, 0.63 mmol), O-(2,4-bistrifluoromethylbenzyl)hydroxylamine hydrochloride (342 mg, 1.16 mmol) and anhydrous NaOAc (141 mg, 1.72 mmol) in EtOH (10 mL) was stirred for 15 hours at RT. The reaction mixture was concentrated under vacuum and the residue filtered through a pad of silica (eluting with CHCl3). Purification by radial thin layer chromatography (eluting with CH2Cl2/PE, 1:9 to 3:7) afforded N-{2-[(2,4-bistrifluoromethylbenzyloxyimino)methyl]-4-chlorophenyl}-trifluoromethanesulfonamide 65 (192 mg, 58%), as a yellow solid. M.p. 65-67° C. 1H n.m.r. (200 MHz, CDCl3) δ 10.38, br s, 1H, 8.20, s, 1H, 7.97, s, 1H, 7.86, d, J=8.0 Hz, 1H, 7.75, d, J=8.0 Hz, 1H; 7.65, d, J=8.8 Hz, 1H, 7.35, dd, J=2.4 and 8.8 Hz, 1H, 7.28, d, J=2.4 Hz, 1H, 5.44, s, 2H.

1. concentrationThe reaction mixture was concentrated under vacuum
2. filtrationthe residue filtered through a pad of silica (eluting with CHCl3)
3. customPurification
4. washby radial thin layer chromatography (eluting with CH2Cl2/PE, 1:9 to 3:7)