Methyl iodide → 4-Chloro-1-methyl-3-nitro-1,2-dihydropyridin-2-one

To a stirred solution of 4-chloro-3-nitropyridin-2(1H)-one (3.0 g, 17 mmol) in N,N-dimethylformamide (50 mL) was added sodium hydride (60% w/w, 1.0 g, 25.5 mmol) in batches at 0° C. The mixture was stirred at room temperature for 30 minutes. Then iodomethane (2.9 g, 20.4 mmol) was added dropwise to the above solution at room temperature. The resultant solution was stirred at room temperature for 12 hours. Once starting material was consumed, the reaction mixture was quenched with ice water (100 mL) at 0˜10° C., and extracted with ethyl acetate (100 mL*3). The organic phase was washed with brine (100 mL*2), dried over anhydrous sodium sulfate, filtered and concentrated to give a residue. The residue was purified by column chromatography (silica gel, dichloromethane/methanol=10:1) to give 4-chloro-1-methyl-3-nitropyridin-2(1H)-one (3 g, 94%) as a yellow solid. LRMS (M+H+) m/z: calcd 188.0. found 188.

1. customOnce starting material was consumed
2. customthe reaction mixture was quenched with ice water (100 mL) at 0˜10° C.
3. extractionextracted with ethyl acetate (100 mL*3)
4. washThe organic phase was washed with brine (100 mL*2)
5. dry with materialdried over anhydrous sodium sulfate
6. filtrationfiltered
7. concentrationconcentrated
8. customto give a residue
9. customThe residue was purified by column chromatography (silica gel, dichloromethane/methanol=10:1)

ORD record

ord-3bc2353c970d4c14b67ada0b00067f6a

Source dataset

uspto-grants-2016_06

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09371331B2