Hydrochloric Acid → 5-Amino-1,3-dihydrobenzo[de]isochromene-6-carbonitrile

Participants

Reaction Conditions

Reaction Steps

5-Nitro-6-cyano-1H,3H benzo[de]isochromene (14.3 g, 59.5 mmol) was dissolved in diglyme (297 mL). The reaction vessel was cooled in an ice bath, and a mixed solution of tin (I) chloride (45.1 g, 238 mmol) and concentrated hydrochloric acid (159 mL) was added slowly while the internal temperature was kept below 5° C. The reaction solution was stirred at 5° C. for 2 hours, and then added to a mixture of 50% aqueous sodium hydroxide solution (476 mL) and ice (1400 mL) while stirring vigorously. The precipitate was collected by filtration, and then dissolved in ethyl acetate. The solution was washed with brine, dried over anhydrous sodium sulfate, and concentrated under reduced pressure. The resulting crude product was purified by silica gel column chromatography using ethyl acetate, and dried under reduced pressure. The title compound was obtained as pale yellow solid (6.7 g, 53%).

Provenance & Evidence