反应详情

温度

0 °C

Pyridine (8.86 g, 91.3 mmol) is added to a solution of 2-cyclopentyl-6-methoxy-isonicotinamide (3.35 g, 15.2 mmol) in DCM (100 mL). The mixture is cooled to 0° C. before trifluoroacetic acid anhydride (9.58 g, 45.6 mmol) is added portionwise. The mixture is stirred at 0° C. for 1 h before it is diluted with DCM (100 mL) and washed with sat. aq. NaHCO3 solution (100 mL) and brine (100 mL). The separated org. phase is dried over MgSO4, filtered and concentrated. The crude product is purified by CC on silica gel eluting with heptane:EA 9:1 to give 2-cyclopentyl-6-methoxy-isonicotinonitrile (2.09 g) as a pale yellow oil; LC-MS**: tR=0.80 min, [M+1]+=not detectable; 1H NMR (D6-DMSO): δ 1.61-1.82 (m, 6H), 1.94-2.03 (m, 2H), 3.16 (quint, J=7.8 Hz, 1H), 3.89 (s, 3H), 7.15 (s, 1H), 7.28 (s, 1H).

1. additionis added portionwise
2. washwashed with sat. aq. NaHCO3 solution (100 mL) and brine (100 mL)
3. dry with materialphase is dried over MgSO4
4. filtrationfiltered
5. concentrationconcentrated
6. customThe crude product is purified by CC on silica gel eluting with heptane:EA 9:1