[CH3:1][C:2]1[CH:7]=[C:6]([C:8]([F:11])([F:10])[F:9])[CH:5]=[CH:4][N+:3]=1[O-].[C:13]([O:16]C(=O)C)(=[O:15])[CH3:14].C([O-])(O)=O.[Na+]>C(O)C>[C:13]([O:16][CH2:1][C:2]1[CH:7]=[C:6]([C:8]([F:11])([F:10])[F:9])[CH:5]=[CH:4][N:3]=1)(=[O:15])[CH3:14]2-Methyl-4-(trifluoromethyl)pyridine 1-oxide (4.0 g, 22 mmol) was added to acetic anhydride (12 mL) at 120° C. The mixture was refluxed for 1 h. To it was carefully added 10 mL of ethanol. Reflux was continued for 10 min. The mixture was poured into ice, neutralized with NaHCO3, and extracted with Et2O. The organic layer was dried (MgSO4) and concentrated. Chromatography on silica gel (5:2 hexanes/EtOAc) provided the product (3.4 g) as a brown oil. MS (M+H) 220.1.
Loading…