反应详情

To ethyl 6-(4-fluorobenzyl)-4-hydroxy-5-oxo-5,6,7,8-tetrahydro-2,6-naphthyridine-1-carboxylate 2-oxide (2.3 gm, 6.38 mmol) in neat acetic anhydride (24 mL) was stirred under nitrogen at 100° C. for 1 hour. The reaction was concentrated to an oil under reduced pressure and dry methanol (20 mL) was added followed by a methanolic sodium methoxide solution (30% by wt) (4.54 mL, 25.2 mmol). The reaction was stirred at room temperature for 1 hour. The reaction was then concentrated to an oil under reduced pressure and crystallized from a small amount of methanol (˜5 mL). The crystals were collected by filtration, washed an additional 10 mL of methanol and dried in vacuo to give the desired product.

1. concentrationThe reaction was concentrated to an oil under reduced pressure and dry methanol (20 mL)
2. additionwas added
3. concentrationThe reaction was then concentrated to an oil under reduced pressure
4. customcrystallized from a small amount of methanol (˜5 mL)
5. filtrationThe crystals were collected by filtration
6. washwashed an additional 10 mL of methanol
7. customdried in vacuo