反应详情

To a solution of 2,6-dichloronicotinic acid (500 mg, 2.63 mmol, Aldrich 90%) in anhydrous N,N-dimethylformamide (5 mL) were added O-benzotriazol-1-yl-N,N,N′,N′-tetramethyluronium hexafluorophosphate (1.28 g, 3.37 mmol, Aldrich), 1-hydroxybenzotriazole hydrate (456 mg, 3.37 mmol, Aldrich) followed by N,N-diisopropylethylamine (1.3 g, 10.0 mmol) and N,O-dimethylhydroxylamine hydrochloride (306 mg, 3.15 mmol, Aldrich) at 0° C. The reaction was stirred for 1-2 hrs, treated with water and extracted with ethyl acetate. The combined organic extracts were washed with brine, dried and concentrated. The crude product was purified on silica gel with hexanes/ethyl acetate to give 2,6-Dichloro-N-methoxy-N-methyl-nicotinamide as a white solid (304.5 mg, 50% yield). HRMS, observed: 233.9968, Calcd for M+: 233.9963

1. extractionextracted with ethyl acetate
2. washThe combined organic extracts were washed with brine
3. customdried
4. concentrationconcentrated
5. customThe crude product was purified on silica gel with hexanes/ethyl acetate