1,3-Cyclohexanedione → 7-bromo-3,4-dihydrodibenzo[b,d]furan-1(2H)-one

HRID 2179356Notes

Reaction equation

Cl.[Br:2][C:3]1[CH:4]=[C:5]([O:9]N)[CH:6]=[CH:7][CH:8]=1.[C:11]1(=O)[CH2:16][CH2:15][CH2:14][C:13](=[O:17])[CH2:12]1.[OH-].[Na+]>OS(O)(=O)=O.C(O)(=O)C.O>[Br:2][C:3]1[CH:8]=[CH:7][C:6]2[C:12]3[C:13](=[O:17])[CH2:14][CH2:15][CH2:16][C:11]=3[O:9][C:5]=2[CH:4]=1

Participants

Conditions

Temperature: 110 °C

Procedure

A mixture of the product of Example 60, step B (9.0 g, 40.1 mmol) and cyclohexane-1,3-dione (6.74 g, 60.1 mmol) in 10% H2SO4/acetic acid (100 mL) was heated at 110° C. for 12 h. After cooling to ambient temperature, the reaction mixture was diluted with water, basified by treating with 10 N NaOH and extracted with dichloromethane. The organic layer was washed with brine, dried over sodium sulfate, filtered and concentrated in vacuo to give the crude material which was purified by flash column chromatography (SiO2, 90:10 hexanes/ethyl acetate) to provide 7-bromo-3,4-dihydrodibenzo[b,d]furan-1(2H)-one (6.8 g, 64%) as a pale yellow solid: 1H NMR (CDCl3, 300 MHz) δ 7.91 (d, J=8.1 Hz, 1H), 7.65 (d, J=1.5 Hz, 1H), 7.45 (dd, J=8.1, 1.5 Hz, 1H), 3.03 (t, J=6.3 Hz, 2H), 2.61 (t, J=6.3 Hz, 2H), 2.35-2.24 (m, 2H).

Workup

temperatureAfter cooling to ambient temperature
extractionextracted with dichloromethane
washThe organic layer was washed with brine
dry with materialdried over sodium sulfate
filtrationfiltered
concentrationconcentrated in vacuo
customto give the crude material which
customwas purified by flash column chromatography (SiO2, 90:10 hexanes/ethyl acetate)

Sources & evidence

ORD record: ord-6872d105759e4ba98b7b891248eada21
Source dataset: uspto-grants-2015_06
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US09067949B2

Reaction notes

Loading…