Phosphorus oxide (P4O10) → HCID 66700093, compound

Phosphorus pentoxide (5.04 g, 35.5 mmol) was added portion-wisely to a stirred solution of (2,6-dibromo-9H-xanthen-9-yl)methanol (10-1) (1.01 g, 2.73 mmol) in toluene (100 mL) and the suspension was heated under reflux for 20 min. The mixture was allowed to cool to rt and toluene was removed by decantation. The residual solid was washed with toluene (2×100 mL) by further decantation. The combined organics were cooled in an ice bath and brine (400 mL) was added slowly. The layers were separated and the organic washed with water (300 mL), brine (300 mL), dried over anhydrous MgSO4 and evaporated to dryness, to give a yellow oily solid. The product was purified by column chromatography (SiO2, O-10% EtOAc/isohexanes) to give 2,7-dibromodibenzo[b,f]oxepine (10-2) (763 mg, 79% yield) as a clear oil. 1H NMR (CDCl3): δ 7.41-7.36 (1H, m), 7.33-7.31 (1H, m), 7.29-7.24 (2H, m), 7.04-6.99 (2H, m), 6.68-6.57 (2H, m) ppm.

1. temperaturethe suspension was heated
2. temperatureunder reflux for 20 min
3. customtoluene was removed by decantation
4. washThe residual solid was washed with toluene (2×100 mL) by further decantation
5. temperatureThe combined organics were cooled in an ice bath
6. additionbrine (400 mL) was added slowly
7. customThe layers were separated
8. washthe organic washed with water (300 mL), brine (300 mL)
9. dry with materialdried over anhydrous MgSO4
10. customevaporated to dryness
11. customto give a yellow oily solid
12. customThe product was purified by column chromatography (SiO2

ORD record

ord-d119afc988c64a7a863b6404b3c790e6

Source dataset

uspto-grants-2015_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08999967B2