Ethylene Glycol → 2-(5-Bromo-2-fluorophenyl)-1,3-dioxolane

To a 3 neck round bottom flask, fitted with a Dean-Stark apparatus, was added 5-bromo-2-fluorobenzaldehyde (5 g, 24.6 mmol), ethane-1,2-diol (4.12 ml, 73.9 mmol), and p-toluenesulfonic acid (424 mg, 2.46 mmol). The resulting mixture was placed under nitrogen, dissolved in anhydrous toluene (100 ml) and heated under reflux for 18 h. After cooling, the mixture was concentrated in vacuo. The residue was diluted with EtOAc (50 ml) and the organic phase was washed with sat. NaHCO3 solution (30 ml), brine (30 ml), dried (Na2SO4) and concentrated in vacuo. The crude residue was purified by column chromatography with heptane/EtOAc (95:5) as the eluent to give the title compound (4.69 g, 77%). The structure was confirmed by 1H NMR.

1. customTo a 3 neck round bottom flask, fitted with a Dean-Stark apparatus
2. temperatureheated
3. temperatureunder reflux for 18 h
4. temperatureAfter cooling
5. concentrationthe mixture was concentrated in vacuo
6. additionThe residue was diluted with EtOAc (50 ml)
7. washthe organic phase was washed with sat. NaHCO3 solution (30 ml), brine (30 ml)
8. dry with materialdried (Na2SO4)
9. concentrationconcentrated in vacuo
10. customThe crude residue was purified by column chromatography with heptane/EtOAc (95:5) as the eluent

ORD record

ord-c6c4602c56e7453eb347e2f3f6ab14c7

Source dataset

uspto-grants-2015_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09102688B2