反应详情

N,O-dimethylhydroxylamine hydrochloride (500 mg, 5 mmol) was added to a mixture of N,N,N′,N′-tetramethyl-O-(7-azabenzotriazol-1-yl)uronium hexafluorophosphate (1400 mg, 3.7 mmol), N,N-diisopropylethylamine (1000 μL, 7 mmol) and 5-bromopyridine-2-carboxylic acid (500 mg, 2 mmol, Frontier Scientific catalog# B1704) in N,N-dimethylformamide (10 mL). The reaction mixture was stirred overnight at room temperature and was complete by LC/MS. The reaction was partitioned between water and EtOAc. The combined organic layer was washed with brine, dried over MgSO4, filtered and concentrated to give the crude product. The product was purified on by FCC on silica gel eluting a hexane: EtOAc (0-30%) gradient to give 5-bromo-N-methoxy-N-methylpyridine-2-carboxamide clear oil (0.50 g, 60%). LCMS calculated for C8H10BrN2O2(M+H)+: m/z=244.9, 246.9; found: 244.9, 246.9.

1. customThe reaction was partitioned between water and EtOAc
2. washThe combined organic layer was washed with brine
3. dry with materialdried over MgSO4
4. filtrationfiltered
5. concentrationconcentrated
6. customto give the crude product
7. customThe product was purified on by FCC on silica gel eluting a hexane