38940-62-4

142337-95-9

The general procedure for the synthesis of 3-bromo-5-ethylpyridine using 3-acetyl-5-bromopyridine as starting material was as follows: sodium hydroxide (10 g, 0.25 mol) and hydrazine monohydrate (10 mL) were added sequentially to a solution of 3-acetyl-5-bromopyridine (5 g, 25 mmol) dissolved in diethylene glycol (18 mL). The reaction mixture was heated to 140 °C and maintained at this temperature for 6 hours. After completion of the reaction, the mixture was partitioned between water and ether. The organic layer was separated, washed with brine and subsequently dried and concentrated with anhydrous magnesium sulfate. Purification of the residue by fast silica gel column chromatography (eluent: 0% to 40% hexane solution of ethyl acetate) afforded the target product 3-bromo-5-ethylpyridine (3 g, 65% yield). The product was characterized by 1H NMR (400 MHz, CDCl3): δ 1.26 (t, J = 7.6 Hz, 3H), 2.65 (q, J = 7.6 Hz, 2H), 7.67 (s, 1H), 8.37 (s, 1H), 8.51 (s, 1H).