Citric Acid → (2S)-2-[1-(3-chloro-2-pyridyl)pyrazolo[4,5-e]pyrimidin-4-yl]oxy-4-hydroxy-N-(5-methyl-2-pyridyl)butanamide

Participants

Reaction Conditions

Reaction Steps

Trimethylaluminium (0.347 mL, 0.69 mmol) was added to 5-methylpyridin-2-amine (71.7 mg, 0.66 mmol) in toluene (8 mL) cooled to 0° C. under nitrogen. The resulting solution was stirred at 0° C. for 20 minutes. (3S)-3-(1-(3-chloropyridin-2-yl)-1H-pyrazolo[3,4-d]pyrimidin-4-yloxy)dihydrofuran-2(3H)-one (Intermediate T1) (200 mg, 0.60 mmol) in toluene (2 mL) and the reaction was allowed to warm to room temperature and stirred for 1 hour. The reaction was then heated at 50° C. for 2 hours. The reaction mixture was allowed to cool and was neutralised with citric acid (1M, aq.) and then diluted with water (50 mL) and ethyl acetate (50 mL). The organic layer was separated and the aqueous layer re-extracted with ethyl acetate (50 mL). The combined organics were dried (MgSO4), filtered and evaporated. The crude product was purified by flash silica chromatography, eluting with 0 to 10% MeOH in DCM to afford the product (185 mg, 69.8%). 1H NMR (400 MHz, CDCl3) 2.30 (3H, s) 2.33-2.40 (1H, m), 2.44-2.52 (1H, m), 2.55 (1h, s), 3.83-3.92 (2H, m), 6.07-6.10 (1H, m), 7.46-7.49 (1H, m), 7.52-7.55 (1H, m), 8.00-8.02 (1H, m), 8.09-8.10 (1H, m), 8.13 (1H, d), 8.47 (1H, s), 8.61-8.62 (1H, m), 8.64 (1H, s), 8.68 (1H, s); m/z (ESI+) (M+H)+=440; HPLC tR=1.68 min.

Provenance & Evidence