1,2-Dibromoethane → 3,4-Dihydro-7-(4-methyl-1H-imidazol-1-yl)pyrido[2,1-c][1,4]oxazine-1,6-dione

Temperature

90 °C

N,N-Dimethylformamide (850 mL) was added to a mixture of 5-(4-methyl-1H-imidazol-1-yl)-6-oxo-1,6-dihydropyridine-2-carboxylic acid hydrochloride salt (C3) (65 g, 250 mmol), 1,2-dibromoethane (52.5 g, 280 mmol) and cesium carbonate (124 g, 381 mmol), and the reaction mixture was heated to 90° C. for 6 hours. After allowing the reaction to cool to room temperature, the mixture was filtered through Celite, and the filtrate was concentrated in vacuo. The residue was dissolved in dichloromethane (500 mL), washed with saturated aqueous sodium chloride solution (100 mL), washed with water (50 mL), dried over magnesium sulfate, filtered, and concentrated under reduced pressure. The resulting solid was washed with acetonitrile to provide the product. Yield: 46.5 g, 190 mmol, 76%. 1H NMR (400 MHz, CDCl3) δ 2.30 (d, J=0.8 Hz, 3H), 4.38-4.42 (m, 2H), 4.66-4.70 (m, 2H), 7.15-7.17 (m, 1H), 7.43 (AB quartet, JAB=7.7 Hz, ΔνAB=33.4 Hz, 2H), 8.33 (d, J=1.4 Hz, 1H).

1. customthe reaction
2. temperatureto cool to room temperature
3. filtrationthe mixture was filtered through Celite
4. concentrationthe filtrate was concentrated in vacuo
5. dissolutionThe residue was dissolved in dichloromethane (500 mL)
6. washwashed with saturated aqueous sodium chloride solution (100 mL)
7. washwashed with water (50 mL)
8. dry with materialdried over magnesium sulfate
9. filtrationfiltered
10. concentrationconcentrated under reduced pressure
11. washThe resulting solid was washed with acetonitrile
12. customto provide the product

ORD record

ord-6ff40920bc4f44fbbc747520641fbce9

Source dataset

uspto-grants-2014_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08697673B2