反应详情

A solution of sodium nitrite (14.8 g, 214 mmol) in 30 mL of water was slowly added to the solution of 6-amino-3,3-dimethyl-indan-1-one (14.0 g, 85.8 mmol) in 30 mL of 48% tetrafluoroboric acid and 30 mL of water at 0°-5° C. After being stirred for 30 min, the mixture was filtered, and the solids were washed with cold 5% tetrafluoroboric acid and dried in vacuum. The solids were then added in several portions into a boiling solution of 50 mL of sulfuric acid in 0.5 liter of water. After refluxing for 1 hour, the solution was cooled to room temperature and extracted with ethyl acetate (100 mL×3). The combined extracts were dried over magnesium sulfate and evaporated. The residue was purified by flash chromatography (EtOAc:hexane=1:10 to 1:2) to give 7.60 g (50% yield) of the title compound as a solid; 1H-NMR (CDCl3) δ 1.40 (s, 6H), 2.64 (s, 2H), 7.13 (s, 1H),7.18 (d, J=8.2 Hz, 1H), 7.39 (d, J=8.2 Hz, 1H); MS m/e 177 (MH+).

1. filtrationthe mixture was filtered
2. washthe solids were washed with cold 5% tetrafluoroboric acid
3. customdried in vacuum
4. additionThe solids were then added in several portions into a boiling solution of 50 mL of sulfuric acid in 0.5 liter of water
5. temperatureAfter refluxing for 1 hour
6. extractionextracted with ethyl acetate (100 mL×3)
7. dry with materialThe combined extracts were dried over magnesium sulfate
8. customevaporated
9. customThe residue was purified by flash chromatography (EtOAc:hexane=1:10 to 1:2)