Aluminium lithium hydride → (4-(Benzyloxy)-6-chloropyrazolo[1,5-a]pyrazin-3-yl)methanol

A solution of methyl 4-(benzyloxy)-6-chloropyrazolo[1,5-a]pyrazine-3-carboxylate 5.35 (427 mg, 1.34 mmol) in THF (6 mL) was cooled to 0° C. under argon. A solution of lithium aluminum hydride in THF (1 M, 1.52 mL, 1.52 mmol) was then added slowly and mixture was warmed to rt and stirred for 18 hours. Mixture was diluted with ether and cooled to 0° C. It was then quenched by addition of 0.060 mL water, 0.060 mL 15% NaOH (aq), and 0.18 mL of water and warmed to room temperature. After 15 minutes, MgSO4 was added and mixture stirred for 20 minutes. Mixture was filtered and filtrate was concentrated under reduced pressure. The resulting residue was purified by silica gel column chromatography (0-50% ethyl acetate/hexanes) to yield (4-(benzyloxy)-6-chloropyrazolo[1,5-a]pyrazin-3-yl)methanol 5.51 (143 mg).

1. temperaturecooled to 0° C
2. customIt was then quenched by addition of 0.060 mL water, 0.060 mL 15% NaOH (aq), and 0.18 mL of water
3. temperaturewarmed to room temperature
4. waitAfter 15 minutes
5. additionMgSO4 was added
6. stirringmixture stirred for 20 minutes
7. filtrationMixture was filtered
8. concentrationfiltrate was concentrated under reduced pressure
9. customThe resulting residue was purified by silica gel column chromatography (0-50% ethyl acetate/hexanes)

ORD record

ord-ffe08ad211f748489cd2c86afc36cf46

Source dataset

uspto-grants-2016_06

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09376441B2