Oxygen → 2-(Benzo[d]thiazol-2-yl)quinolin-8-ol

Participants

Reaction Conditions

Reaction Steps

To introduce a benzo[d]thiazol group into an 8-hydroxyquinoline compound, 2-aminothiophenol (123 mg, 1.1 mmol) and 8-hydroxyquinoline-2-carboxylic acid (189 mg, 2 mmol) were dissolved in dry toluene (30 ml) with blown nitrogen to prevent oxidation which is caused by oxygen in air. The solution was heated to 40° C. and phosphorus trichloride (0.1 ml, 1.1 mmol) was slowly added thereto. Then, the reaction solution was heated at 100° C. for 24 hours and allowed to cool. The reaction mixture was extracted with a 20% aqueous sodium carbonate solution, distilled water and dichloromethane, dried and recrystallized with dichloromethane and hexane to yield 2-(benzo[d]thiazol-2-yl)quinolin-8-ol, the compound of Formula 1 as a light green solid (yield: 75%).

Provenance & Evidence