[CH3:1][C:2]1[N:10]=[C:9]([CH3:11])[CH:8]=[CH:7][C:3]=1[C:4](O)=[O:5].C(Cl)Cl.C(C1NC=CN=1)(C1NC=CN=1)=O.Cl.[CH3:28][NH:29][O:30][CH3:31]>CN(C=O)C>[CH3:31][O:30][N:29]([CH3:28])[C:4](=[O:5])[C:3]1[CH:7]=[CH:8][C:9]([CH3:11])=[N:10][C:2]=1[CH3:1]
To a flask containing 2,6-dimethylnicotinic acid (2.80 g, 18.5 mmol) was added CH2Cl2 and DMF (6 mL). The suspension was stirred at room temperature as carbonyl diimidazole (3.50 g, 21.6 mmol) was added. The suspension remained throughout the day and was allowed to stir overnight at room temperature. After 18 hours, N,O-dimethylhydroxylamine hydrochloride (3.00 g, 30.8 mmol) was introduced and the mixture was stirred at room temperature again for 24 hours. The reaction mixture was quenched with water and 1 N NaOH, and extracted with CH2Cl2 (4×50 mL). The combined organics were washed with brine, dried over Na2SO4, filtered and concentrated to give a colorless oil. Flash chromatography on silica gel (50% EtOAc-hexane) afforded the title compound as a colorless oil.
Wird geladen…
