反应详情

To a mixture of benzyl 3-{3-[1-(4-amino-5-oxopyrido[2,3-d]pyrimidin-8(5H)-yl)ethyl]-5-chloro-2-ethoxy-6-methylphenyl}azetidine-1-carboxylate (23 mg, 0.042 mmol) and 5% palladium on carbon (10 mg) in methanol (1.6 mL) was added 0.25 M hydrogen chloride in water (0.42 mL, 0.10 mmol). The suspension was hydrogenated under balloon pressure of H2 at room temperature for 2 hours. After filtered off the catalyst, the filtrate was neutralized with sat. NaHCO3 solution, extracted with dichloromethane. The combined organic layers were dried over MgSO4 and concentrated to give 4-amino-8-[1-(3-azetidin-3-yl-5-chloro-2-ethoxy-4-methylphenyl)ethyl]pyrido[2,3-d]pyrimidin-5(8H)-one (7 mg, 40%). To a mixture of the crude amine in acetonitrile (0.1 mL)/methanol (0.1 mL)/tetrahydrofuran (0.1 mL) was added N,N-diisopropylethylamine (0.02 mL, 0.1 mmol), followed by acetone (0.03 mL, 0.4 mmol). The mixture was stirred for 30 minutes before the addition of sodium triacetoxyborohydride (0.044 g, 0.21 mmol). The reaction was stirred at room temperature for 4 hours, then quenched with water and purified on RP-HPLC (XBridge C18 column, eluting with a gradient of acetonitrile/water containing 0.05% TFA, at flow rate of 30 mL/min) to give the desired product as TFA salt. The product was isolated as a racemic mixture. LCMS calculated for C24H31ClN5O2 (M+H)+: m/z=456.2; Found: 456.1.

1. filtrationAfter filtered off the catalyst
2. extractionextracted with dichloromethane
3. dry with materialThe combined organic layers were dried over MgSO4
4. concentrationconcentrated