7-Bromo-5-chloro-2,3-dihydropyrano(4,3,2-de)quinoline → 7-Bromo-2,3-dihydropyrano[4,3,2-de]quinoline

Participants

Reaction Steps

To a solution of 7-bromo-5-chloro-2,3-dihydropyrano[4,3,2-de]quinoline (0.220 g; 0.773 mmol) in trifluoroacetic acid (7.5 ml) was added zinc dust (0.253 g; 3.87 mmol) and the reaction was stirred at room temperature for 16 h. The suspension was filtered, concentrated under reduced pressure, diluted with a solution of sodium hydroxide 1N and extracted with dichloromethane. The organic layer was washed with water and brine, dried over magnesium sulphate and concentrated under reduced pressure. Purification by flash chromatography on silica gel using a gradient of ethyl acetate (5-80%) in heptane furnished 0.047 g (24%) of 7-bromo-2,3-dihydropyrano[4,3,2-de]quinoline as a white solid.

Provenance & Evidence