Synthesis
Iodobenzene diacetate (10.35 mmol, 3.3 g) was dissolved in 12 mL of a solvent mixture of acetonitrile and water (2:1, v/v) under nitrogen atmosphere and cooled to 0°C. To this solution was added quinolin-5-ol (3.45 mmol, 0.50 g) and the reaction was stirred at this temperature for 1 hour. Upon completion of the reaction, 40 mL of water was added to dilute the reaction mixture, followed by extraction with ethyl acetate (3 x 20 mL). The organic phases were combined, washed with saturated saline, dried over anhydrous sodium sulfate and concentrated under reduced pressure to afford the target product 5,8-quinoline quinone (4) as a yellow solid in 82% yield. Mass spectrum (ESI) m/z = 160 [M + H]+.
References
[1] Tetrahedron Letters, 1990, vol. 31, # 34, p. 4871 - 4872
[2] Organic and Biomolecular Chemistry, 2011, vol. 9, # 13, p. 4959 - 4976
[3] European Journal of Medicinal Chemistry, 2018, vol. 154, p. 199 - 209
[4] Synthetic Communications, 1999, vol. 29, # 18, p. 3063 - 3066