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

Temperature

5 °C

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%).

1. temperatureThe reaction vessel was cooled in an ice bath
2. customwas kept below 5° C
3. stirringwhile stirring vigorously
4. filtrationThe precipitate was collected by filtration
5. dissolutiondissolved in ethyl acetate
6. washThe solution was washed with brine
7. dry with materialdried over anhydrous sodium sulfate
8. concentrationconcentrated under reduced pressure
9. customThe resulting crude product was purified by silica gel column chromatography
10. customdried under reduced pressure

ORD record

ord-324a1f762bf342329ccb19ab882bae94

Source dataset

uspto-grants-2012_06

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08193351B2