Methanol → 3-(hydroxymethyl)-6a,7,9,10-tetrahydro-[1,4]oxazino[4,3-a]pyrido[3,2-e]pyrazin-6(5H)-one

Temperature

-45 °C

Methyl 6-oxo-5,6,6a,7,9,10-hexahydro-[1,4]oxazino[4,3-a]pyrido[3,2-e]pyrazine-3-carboxylate (1000 mg, 3.80 mmol) was taken up in tetrahydrofuran (47 mL) in an inert environment. To the stirred suspension at room temperature was added NaH (228 mg, 5.70 mmol, 60% dispersion in mineral oil) and stirred 30 minutes. The reaction was then cooled to −45° C. and lithium aluminum hydride (11.4 mL, 1M in THF) was added. The reaction was stirred at a temperature between −20 and −10° C. for 1 hour. The reaction was then cooled back to −78° C. and methanol (3 ml) followed by water (1 ml) was added. The reaction was allowed to stir at ambient temperature for 2 hours and then poured into ethyl acetate (400 ml) and water (100 ml). The biphasic mixture was stirred vigorously and then filtered through a medium frit. The filtrate was collected. The layers were separated and the aqueous phase was extracted with ethyl acetate (1×100 ml). The organic layers were combined, washed with brine (100 ml), and concentrated to yield 657 mg (73.5%) of the title compound as a white solid. [M+H] calc'd for C11H13N3O3, 236; found, 236.

1. stirringThe reaction was stirred at a temperature between −20 and −10° C. for 1 hour
2. temperatureThe reaction was then cooled back to −78° C.
3. additionwas added
4. stirringto stir at ambient temperature for 2 hours
5. stirringThe biphasic mixture was stirred vigorously
6. filtrationfiltered through a medium frit
7. customThe filtrate was collected
8. customThe layers were separated
9. extractionthe aqueous phase was extracted with ethyl acetate (1×100 ml)
10. washwashed with brine (100 ml)
11. concentrationconcentrated

ORD record

ord-0a4588300dab4fa790ebec5d02741dae

Source dataset

uspto-grants-2014_09

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08822470B2