反应详情

A solution of N-(4-chloro-2-propionylphenyl)trifluoromethanesulfonamide 22 (3.21 mg, 10.17 mmol), O-(2,4-bistrifluoromethylbenzyl)hydroxylamine hydrochloride (3.16 mg, 10.68 mmol) and anhydrous NaOAc (876 mg, 10.68 mmol) in EtOH (120 mL) was stirred for 15 h at RT. The reaction mixture was concentrated under vacuum and the residue filtered through a pad of silica (eluting with CH2Cl2/PE, 2:3). Purification by radial thin layer chromatography (eluting with CH2Cl2/PE, 1:9) afforded a pale yellow solid which was recrystallized from CH2Cl2/PE to give N-{2-[1-(2,4-bistrifluoromethylbenzyloxyimino)propyl]-4-chlorophenyl}trifluoromethanesulfonamide 76 (3.70 g, 65%), as a pale yellow oil. 1H n.m.r. (200 MHz, CDCl3) δ 10.96, br s, 1H; 7.96, s, 1H; 7.85, d, J=8.4 Hz, 1H; 7.72, d, J=8.4 Hz, 1H; 7.61, d, J=8.8 Hz, 1H; 7.49, d, J=2.4 Hz, 1H; 7.33, dd, J=2.4 and 8.8 Hz, 1H; 5.45, s, 2H; 2.88, q, J=7.6 Hz, 2H; 1.21, t, J=7.6 Hz, 3H. HRMS (M+) 556.0254.

1. concentrationThe reaction mixture was concentrated under vacuum
2. filtrationthe residue filtered through a pad of silica (eluting with CH2Cl2/PE, 2:3)
3. customPurification
4. washby radial thin layer chromatography (eluting with CH2Cl2/PE, 1:9)
5. customafforded a pale yellow solid which
6. customwas recrystallized from CH2Cl2/PE