7-bromo-3-methylquinoline

59278-65-8

123-38-6

1375108-41-0

General procedure for the synthesis of 7-bromo-3-methylquinoline from 2-amino-4-bromobenzaldehyde and propionaldehyde: KOH (5.61 g, 100 mmol) was dissolved in ethanol (50 mL) to prepare a solution, which was subsequently added drop-wise to a reaction flask containing a 2-amino-4-bromobenzaldehyde (60.6 g, 303 mmol) and propionaldehyde (17.6 g, 303 mmol ) in a reaction flask of the mixture. Anhydrous ethanol (200 mL) was added to the reaction system under nitrogen protection. The reaction mixture was heated to reflux and the reflux reaction was maintained for 3 hours. Upon completion of the reaction, the mixture was cooled to room temperature and subsequently concentrated by rotary evaporator to remove ethanol. Water was added to the concentrated mixture and extracted with dichloromethane (3 x 100 mL). All organic layers were combined, washed with water and dried over anhydrous sodium sulfate, after which it was concentrated under vacuum. The crude product obtained was ground with ether to give the final 7-bromo-3-methylquinoline (48.6 g, 219 mmol, 72% yield) as a light brown solid. Mass spectrum (electrospray ionization) m/e 221.9, 223.9 [M + H]+ (bromine isotope mode).