Propionic Acid → 2-Ethylthiazolo[4,5-c]quinoline

Participants

Reaction Steps

Propionyl anhydride (20 mL) was added to a suspension of 3-amino-quinoline4-thiol (15 g) in propionic acid (100 mL). The reaction mixture was heated at reflux overnight and then filtered to remove a precipitate. The filtrate was concentrated under vacuum. The residue was taken up in dichloromethane (200 mL), washed with sodium bicarbonate then with water, and then dried over magnesium sulfate. The solution was filtered through a layer of silica gel eluting first with 1:1 ethyl acetate:hexane and then with ethyl acetate. The filtrate was evaporated to provide 2.6 g of 2-ethylthiazolo[4,5-c]quinoline as a yellow oil.

Provenance & Evidence