General procedure for the synthesis of 4-(pyridin-2-yl)thiazol-2-amine from 2-bromo-1-(2-pyridinyl)ethanone and thiourea (CAS: 17356-08-0): 2-bromo-1-(2-pyridinyl)ethanone (0.01 mol, ca. 0.76 g), thiourea (0.01 mol), and 50 mL of ethanol were added to a 100 mL round-bottomed flask, and the mixture was heated to reflux for for 4 hours. After completion of the reaction, the ethanol solvent was removed by distillation under reduced pressure. The crude product was purified by column chromatography using dichloromethane (DCM): methanol (MeOH): ammonium hydroxide (NH4OH) (20:1:0.1, v/v) as mobile phase. 4-(Pyridin-2-yl)thiazol-2-amine was finally obtained as a white solid in a yield of 1.41 g in 79.6%.
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