Water → 3-[(Cyclopent-3-en-1-yl)methyl]-2-methoxypyridine

Participants

Reaction Steps

Cyclopent-3-enyl-(2-methoxy-pyridin-3-yl)-methanone (10.0 g, 49.3 mmol), hydrazine hydrate (6.33 g, 198 mmol) and pulverized potassium hydroxide (85% KOH) (16.8 g, 300 mmol) were warmed in ethylene glycol (100 mL) until solution occurred at 100° C. then to 180° C. for 18 h. The mixture was cooled to room temperature and treated with water (100 mL) then extracted with 50% EtOAc/hexanes (3×80 mL). The organic layer was washed with saturated aqueous NaCl solution, dried over Na2SO4 and concentrated to an oil. Purification by chromatography on silica gel eluting with 10% EtOAc/hexanes provided the desired product as an oil 4.75 g (51%). (TLC 10% Et2O/hexanes Rf 0.80); 1H NMR (400 MHz, CDCl3) δ 8.01 (dd, J=5.0, 1.7 Hz, 1H), 7.37 (dd, J=7.2, 1.5 Hz, 1H), 6.81 (dd, J=7.2, 5.0 Hz, 1H), 5.66 (s, 2H), 3.95 (s, 3H), 2.61 (m, 3H), 2.40 (m, 2H), 2.03 (m, 2H); GCMS m/z 189 (M)+. 3-Cyclopent-3-enyl-1H-pyrazolo[3,4-b]pyridine was also isolated 4.45 g (49%).

Provenance & Evidence