Dihydrobenzofuran → 5-Bromo-2,3-dihydro-1-benzofuran

To an ice-cooled dioxane (30 ml) was slowly added liquid bromine (2.66 g) and this mixture was stirred for 30 minutes at said temperature. To the mixture was added dropwise 2,3-dihydrobenzofuran (2 g), and the resulting mixture was stirred for 3 hours at room temperature. The solvent was removed under reduced pressure. The residue was dissolved in AcOEt (50 ml) and the solution was washed with saturated aqueous NaHCO3 solution and brine, and dried over MgSO4. The solvent was evaporated to give an orange oil as a crude product. The crude product was purified on an SiO2 column (hexane-AcOEt 20:1) to give 2.33 g of 5-bromo-2,3 dihydrobenzofuran as white crystals (yield 70.3%).

1. stirringthe resulting mixture was stirred for 3 hours at room temperature
2. customThe solvent was removed under reduced pressure
3. dissolutionThe residue was dissolved in AcOEt (50 ml)
4. washthe solution was washed with saturated aqueous NaHCO3 solution and brine
5. dry with materialdried over MgSO4
6. customThe solvent was evaporated
7. customto give an orange oil as a crude product
8. customThe crude product was purified on an SiO2 column (hexane-AcOEt 20:1)

ORD record

ord-24951c3c95df4ebd9d2967710a07b3ef

Source dataset

uspto-grants-2001_12

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06333324B1