Synthesis
7-Nitro-1,2,3,4-tetrahydroquinoline (60 g, 0.337 mol) was used as raw material and dissolved in dichloromethane (4.5 L). Dichlorodicyanobenzoquinone (152.9 g, 0.6734 mol) was added in batches at room temperature and the reaction was stirred for 1 hour. After completion of the reaction, filtration was carried out and the filter cake was washed with dichloromethane (500 mL x 2) and stirred for 5 min each time before filtration again. The organic phases were combined and washed sequentially with 10% sodium hydroxide solution (500 mL x 2) and saturated sodium chloride solution (500 mL). The organic phase was dried over anhydrous sodium sulfate and concentrated to dryness under reduced pressure. The resulting orange solid was stirred with a solvent mixture of petroleum ether:ethyl acetate (5:1, 250 mL) for 30 min, and 7-nitroquinoline (53 g, 90.3% yield) was obtained after filtration.
References
[1] Chemistry - A European Journal, 2017, vol. 23, # 57, p. 14167 - 14172
[2] Synthetic Communications, 2018, vol. 48, # 11, p. 1291 - 1298
[3] Angewandte Chemie - International Edition, 2018, vol. 57, # 35, p. 11262 - 11266
[4] Angew. Chem., 2018, vol. 130, # 35, p. 11432 - 11436,5
[5] Patent: CN107353245, 2017, A. Location in patent: Paragraph 0017; 0018
