反应详情

2-Fluorobenzyl bromide (0.049 mL, 0.39 mmol) was added to a stirred suspension of 5-(4-fluorophenyl)-2-hydroxy-6,7-dihydropyrazolo[1,5-a]pyrazin-4(5H)-one (0.092 g, 0.36 mmol) and Cs2CO3 (0.234 g, 0.72 mmol) in ACN (1.85 mL). The mixture was stirred at room temperature for 16 hours. The solvent was evaporated in vacuo. The residue was diluted with water and extracted with AcOEt. The organic layer was separated, washed with a saturated solution of NaCl, dried (Na2SO4), filtered and the solvents evaporated in vacuo. The crude product was purified by flash column chromatography (silica; AcOEt in heptane 0/100 to 50/50). The desired fractions were collected and the solvents evaporated in vacuo to yield 2[(2-fluorobenzyl)oxy]-5-(4-fluorophenyl)-6,7-dihydropyrazolo[1,5-a]pyrazin-4(5H)-one (0.109 g, 85% yield) as a white solid. C19H15F2N3O2. 1H NMR (500 MHz, CDCl3) δ ppm 4.14 (dd, J=6.8, 5.1 Hz, 2H), 4.37 (dd, J=6.9, 5.2 Hz, 2H), 5.30 (s, 2H), 6.37 (s, 1H), 7.04-7.15 (m, 3H), 7.17 (td, J=7.5, 0.9 Hz, 1H), 7.28-7.36 (m, 3H), 7.53 (td, J=7.4, 1.4 Hz, 1H).

1. customThe solvent was evaporated in vacuo
2. additionThe residue was diluted with water
3. extractionextracted with AcOEt
4. customThe organic layer was separated
5. washwashed with a saturated solution of NaCl
6. dry with materialdried (Na2SO4)
7. filtrationfiltered
8. customthe solvents evaporated in vacuo
9. customThe crude product was purified by flash column chromatography (silica; AcOEt in heptane 0/100 to 50/50)
10. customThe desired fractions were collected
11. customthe solvents evaporated in vacuo