Ethylene Glycol → 2-Bromo-5-(1,3-dioxolan-2-YL)pyridine

Participants

Reaction Steps

To a solution of 6-bromonicotinaldehyde (10.1 g, 51.6 mmol) in toluene (400 mL) was added ethylene glycol (11.4 mL, 206 mmol) and p-toluenesulfonic acid (0.98 g, 5.16 mmol), and the reaction mixture was heated to reflux with azeotropic removal of the water using a Dean-Stark trap, for 2.5 h. The mixture was cooled down and washed with saturated NaHCO3 solution and brine. The organic phase was dried over anhydrous MgSO4 and concentrated to afford title compound 300 (11.7 g, 98% yield) as a brown solid, which was used in the next step without further purification. 1H NMR (300 MHz, DMSO-d6) δ (ppm): 8.46 (d, J=2.7 Hz, 1H), 7.65 (dd, J=8.1, 2.7 Hz, 1H), 7.51 (d, J=8.1 Hz, 1H), 5.83 (s, 1H), 4.20-4.00 (m, 4H).

Provenance & Evidence