Hydrogen Bromide → HCID 60155616, compound

Temperature

2.5 °C

To a solution of compound (29a) (3.0 g, 13.9 mmol) in 40% hydrobromic acid (8.0 mL, 54.4 mmol), an aqueous solution (17 mL) of sodium nitrite (1.1 g, 15.7 mmol) was added dropwise under stirring at 0 to 5° C. The solution was allowed to reach room temperature. To the solution, CuBr (1.1 g, 11.2 mmol) and 96% sulfuric acid (0.1 mL) were added, and the mixture was refluxed under stirring for 1 hour. After cooling and subsequent extraction with ethyl acetate, the obtained residue was dissolved in methanol (50 mL). To the obtained mixture, a catalytic amount of concentrated hydrochloric acid (0.1 mL) was added and refluxed for 3 hours. After cooling, the solvent was distilled off and the obtained product was treated with ether (50 mL). The organic layer was dried (over sodium sulfate) and the solvent was distilled off. The obtained residue was subjected to silica gel column chromatography and elution with an n-hexane/ethyl acetate (4:1) solution to give 3.01 g (73%) of compound (30a) as pale yellow liquid matter.

1. customto reach room temperature
2. temperaturethe mixture was refluxed
3. stirringunder stirring for 1 hour
4. temperatureAfter cooling
5. extractionsubsequent extraction with ethyl acetate
6. dissolutionthe obtained residue was dissolved in methanol (50 mL)
7. additionTo the obtained mixture, a catalytic amount of concentrated hydrochloric acid (0.1 mL) was added
8. temperaturerefluxed for 3 hours
9. temperatureAfter cooling
10. distillationthe solvent was distilled off
11. additionthe obtained product was treated with ether (50 mL)
12. dry with materialThe organic layer was dried (over sodium sulfate)
13. distillationthe solvent was distilled off
14. washThe obtained residue was subjected to silica gel column chromatography and elution with an n-hexane/ethyl acetate (4:1) solution

ORD record

ord-5bac7500c8224424ad067b7fec0b3a10

Source dataset

uspto-grants-2015_12

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09221786B2