Diisopropyl 3-(cyanomethyl)-3-[4-(7-[2-(trimethylsilyl)ethoxy]methyl-7H-pyrrolo[2,3-d]pyrimidin-4-yl)-1H-pyrazol-1-yl]cyclobutane-1,1-dicarboxylate (0.3 g, 0.5 mmol) was dissolved in tetrahydrofuran (15 mL, 180 mmol) and lithium tetrahydroborate (0.017 g, 0.77 mmol) was added at 0° C. The reaction was then heated to 50° C. for 30 min. To the reaction was added MeOH (10 mL). The reaction was held at 50° C. for 15 min, then stripped to near dryness. The residue was treated with 1N HCl, then neutralized with solid NaHCO3. The mixture was partitioned between water and EtOAc. The phases were separated and the aq. phase was washed with EtOAc. The combined organic phases were washed with water, then brine, dried over MgSO4, concentrated and purified with Combiflash (silica gel, 0-100% EtOAc/Hex) to give the desired product (0.145 g, 60%) as colorless oil. LCMS calculated for C23H33N6O3Si(M+H)+: 469.2; Found: 469.4.
