Dimethylformamide → (Z)-3-cyclopentyl-3-(4-(7-((2-(trimethylsilyl)ethoxy)methyl)-7H-pyrrolo[2,3-d]pyrimidin-4-yl)-1H-pyrazol-1-yl)acrylonitrile

Participants

Reaction Steps

To a stirred solution of 4-(1H-pyrazol-4-yl)-7-{[2-(trimethylsilyl)ethoxy]methyl}-7H-pyrrolo[2,3-d]pyrimidine (17, 7.260 g, 23.01 mmol) and 3-cyclopentylprop-2-ynenitrile (8, 6.140 g, 34.52 mmol, 1.5 equiv) in N,N-Dimethylformamide (DMF, 40.0 mL, 516 mmol) at room temperature was added solid potassium carbonate (K2CO3, 318 mg, 2.30 mmol, 0.1 equiv). The resulting reaction mixture was stirred at room temperature for 30 min. When LCMS showed the reaction was deemed complete, the reaction mixture was quenched with water (80 mL), extracted with EtOAc (2×150 mL). The combined organic layers were washed with water (80 mL) and brine (50 mL), dried over magnesium sulfate (MgSO4), filtered and concentrated under reduced pressure. The residue was purified by flash chromatography (SiO2, 0-30% EtOAc/hexane gradient elution) to give (Z)-3-cyclopentyl-3-(4-(7((2-(trimethylsilyl)ethoxy)methyl)-7H-pyrrolo[2,3-d]pyrimidin-4-yl)-1H-pyrazol-1-yl)acrylonitrile (19, 8.256 g, 10.0 g theoretical, 82.6% yield) as a colorless syrup. For 19: 1H NMR (CDCl3, 300 MHz) δ ppm 9.15 (bs, 1H), 8.96 (s, 1H), 8.56 (s, 1H), 7.51 (d, 1H, J=3.5 Hz), 6.93 (d, 1H, J=3.5 Hz), 5.75 (s, 2H), 5.29 (s, 1H), 3.62 (m, 1H), 3.60 (t, 2H, J=8.2 Hz), 2.16 (m, 2H), 1.81 (m, 4H), 1.59 (m, 2H), 0.98 (t, 2H, J=8.2 Hz), 0.00 (s, 9H); C23H30N6OSi (MW, 434.61), LCMS (EI) m/e 435.2 (M++H).

Provenance & Evidence