Lithium Hydroxide → 6-tert-butyl-8-fluoro-2-[3-(hydroxymethyl)-4-[1-methyl-5-[[5-(oxetan-3-yl)-6,7-dihydro-4H-pyrazolo[1,5-a]pyrazin-2-yl]amino]-6-oxo-pyridazin-3-yl]-2-pyridyl]phthalazin-1-one

Participants

Reaction Steps

A mixture of 155d (117 mg, 0.175 mmol) and lithium hydroxide.water (73.5 mg, 1.75 mmol) in i-propanol/THF (1:1, 8 mL) and water (1 mL) was stirred at 35° C. for 0.5 h. The mixture was evaporated under reduced pressure and the residue was diluted with water (6 mL). It was then extracted with dichloromethane (3×50 mL). The combined dichloromethane extract was concentrated under reduced pressure and the residue was purified by reverse-phase prep-HPLC to afford 155 (30 mg, 27%) as a yellow solid. MS-ESI: [M+H]+ 628.3. 1H NMR (500 MHz, DMSO-d6) δ 9.40 (s, 1H), 8.64 (d, J=5.5 Hz, 1H), 8.55 (d, J=2.0 Hz, 1H), 7.94 (s, 1H), 7.90 (d, J=1.5 Hz, 1H), 7.79-7.77 (m, 1H), 7.61 (d, J=4.5 Hz, 1H), 6.04 (s, 1H), 7.61-7.60 (m, 1H), 4.61-4.59 (m, 2H), 4.50-4.45 (m, 4H), 4.01-3.99 (m, 2H), 3.78 (s, 3H), 3.69-3.65 (m, 1H), 3.54 (s, 2H), 2.79-2.76 (m, 2H), 1.39 (s, 9H).

Provenance & Evidence