反应详情

A 1M solution of TBAF in THF (0.14 mL, 0.144 mmol) was added to a stirred solution of 2-[4-(tert-butyl-dimethyl-silanyloxy)-phenoxymethyl]-5-(5-fluoro-pyridin-2-yl)-6,7-dihydro-5H-pyrazolo[1,5-a]pyrazin-4-one (45 mg, 0.096 mmol) in THF (0.5 mL). The mixture was stirred at room temperature for 16 hours. The mixture was treated with water and extracted with AcOEt. The organic layer was separated, dried (MgSO4), filtered and the solvents evaporated in vacuo. The crude product was purified by flash column chromatography (silica; 7 N solution of ammonia in MeOH in DCM 0/100 to 10/90). The desired fractions were collected and the solvents evaporated in vacuo to yield 5-(5-fluoro-pyridin-2-yl)-2-(4-hydroxy-phenoxymethyl)-6,7-dihydro-5H-pyrazolo[1,5-a]pyrazin-4-one as a white solid. 1H NMR (500 MHz, DMSO-d6) δ ppm 4.40-4.48 (m, 2H), 4.48-4.55 (m, 2H), 4.99 (s, 2H), 6.65-6.72 (m, 2H), 6.83-6.88 (m, 2H), 6.95 (s, 1H), 7.85 (td, J=8.7, 3.2 Hz, 1H), 7.93 (dd, J=9.1, 4.2 Hz, 1H), 8.50 (d, J=3.2 Hz, 1H), 8.96 (s, 1H).

1. extractionextracted with AcOEt
2. customThe organic layer was separated
3. dry with materialdried (MgSO4)
4. filtrationfiltered
5. customthe solvents evaporated in vacuo
6. customThe crude product was purified by flash column chromatography (silica; 7 N solution of ammonia in MeOH in DCM 0/100 to 10/90)
7. customThe desired fractions were collected
8. customthe solvents evaporated in vacuo