反应详情

To a slurry of 3-(biphenyl-4-yl)furan (100 mg, 0.450 mmol) and Na2CO3 (48 mg, 0.45 mmol) in benzene (1 mL) and MeOH (1 mL) at −10° C. was added bromine (22 μL, 0.43 mmol) dropwise via syringe. After 30 minutes at −10° C., the mixture was diluted with EtOAc and filtered twice. The filtrate was concentrated to give a crude solid which was purified via flash column chromatography with a 0-1% EtOAc/CH2Cl2 gradient eluant to provide 90 mg (74%) of a diasteromeric mixture of 3-(biphenyl-4-yl)-2,5-dihydro-2,5-dimethoxyfuran as a colorless oil. 1H NMR (CDCl3): δ 7.70-7.28 (m, 9H), 6.35 (dd, 0.75H, major isomer, J=0.9, 0.9 Hz), 6.30 (d, 0.25H, minor isomer, J=6.0 Hz), 6.04-6.03 (m, 1H, major+minor isomer), 5.71 (d, 0.75H, major isomer, J=0.9 Hz), 3.60-3.40 (m, 6H). Anal. Calculated for C18H18O3: C, 76.57; H, 6.43. Found: C, 76.52; H 6.38.

1. filtrationfiltered twice
2. concentrationThe filtrate was concentrated
3. customto give a crude solid which
4. customwas purified via flash column chromatography with a 0-1% EtOAc/CH2Cl2 gradient eluant