Citric Acid → (2S)-3-cyclobutoxy-N-(5-methylpyrazin-2-yl)-2-(1-(2-methylpyridin-3-yl)-1H-pyrazolo[3,4-d]pyrimidin-4-yloxy)propanamide

Participants

Reaction Conditions

Reaction Steps

Sodium hydride (19.54 mg, 0.49 mmol) was added to (S)-3-cyclobutoxy-2-hydroxy-N-(5-methylpyrazin-2-yl)propanamide (Intermediate R1) (102 mg, 0.41 mmol) in anhydrous THF (5 mL) at 0° C. under nitrogen. The resulting solution was stirred at 0° C. for 10 minutes and then 4-chloro-1-(2-methylpyridin-3-yl)-1H-pyrazolo[3,4-d]pyrimidine (Intermediate V5) (100 mg, 0.41 mmol) was added. The reaction mixture was allowed to warm to room temperature and stirred for 1 hour. The reaction mixture was neutralised with 1M citric acid and the majority of the THF removed in vacuo. The reaction mixture was diluted with water (20 mL) and ethyl acetate (50 mL). The organic layer was separated and the aqueous layer re-extracted with ethyl acetate (2×50 mL). The combined organics were washed with saturated brine (25 mL), dried (MgSO4) and evaporated. The crude product was purified by flash silica chromatography, eluting with 0 to 5% MeOH in DCM to afford the product (78 mg, 41.6%). 1H NMR (400 MHz, DMSO) δ 1.23-1.36 (m, 1H), 1.38-1.51 (m, 1H), 1.60-1.75 (m, 2H), 1.96-2.07 (m, 2H), 2.13 (s, 3H), 2.27 (s, 3H), 3.71-3.87 (m, 2H), 3.89-3.98 (m, 1H), 5.71-5.78 (m, 1H), 7.28-7.34 (m, 1H), 7.75 (d, 1H), 8.15 (s, 1H), 8.39 (s, 1H), 8.45-8.51 (m, 2H), 8.93 (s, 1H), 11.01 (s, 1H), m/z (ESI+) (M+H)+=461.48; HPLC tR=1.75 min

Provenance & Evidence