29969-57-1

22246-16-8

29969-57-1

Step 4 Synthesis of 2-chloro-6-nitroquinoline: To a solution of 6-nitro-3,4-dihydroquinolin-2(1H)-one (8.2 g, 41.9 mmol) in benzene (150 mL) was added DDQ (9.6 g, 42.5 mmol) and phosphorus triclosan (20.5 mL) sequentially, and the homogeneity of the reaction system was maintained during dropwise addition. The reaction mixture was heated to 90 °C with continuous stirring for 3 hours. Upon completion of the reaction, the mixture was cooled to room temperature and the reaction was subsequently quenched by slowly pouring into 500 mL of ice water. The pH was adjusted to 7 with 4N NaOH solution. extraction was carried out with ethyl acetate (3 x 1 L) and the organic phases were combined. The organic phase was concentrated under reduced pressure to give 8.4 g of 2-chloro-6-nitroquinoline in yellow solid form in 95% yield.