Br[C:2]1[CH:7]=[C:6]([CH3:8])[C:5]([C:9]2[C:10](=[O:16])[CH2:11][CH2:12][C:13]=2[O:14][CH3:15])=[C:4]([CH3:17])[CH:3]=1.[F-].[Cs+].[C:20]1(B(O)O)[CH:25]=[CH:24][CH:23]=[CH:22][CH:21]=1>C1C=CC(P(C2C=CC=CC=2)[C-]2C=CC=C2)=CC=1.C1C=CC(P(C2C=CC=CC=2)[C-]2C=CC=C2)=CC=1.Cl[Pd]Cl.[Fe+2]>[CH3:17][C:4]1[CH:3]=[C:2]([C:20]2[CH:25]=[CH:24][CH:23]=[CH:22][CH:21]=2)[CH:7]=[C:6]([CH3:8])[C:5]=1[C:9]1[C:10](=[O:16])[CH2:11][CH2:12][C:13]=1[O:14][CH3:15]To a mixture of 2-(4-bromo-2,6-dimethylphenyl)-3-methoxy-cyclopent-2-enone (1 g, 3.4 mmol), cesium fluoride (1.5 g, 9.87 mmol), phenylboronic acid (0.5 g, 4.1 mmol) and [1,1′-bis(diphenylphosphino)ferrocene]dichloro-palladium(II) (0.44 g, 0.54 mmol) is added degassed dimethoxyethane (10 ml) and the resulting suspension is stirred under nitrogen for 45 minutes then heated at 80° C. for 4 hrs. After cooling to room temperature the reaction mixture is acidified with 1N aqueous hydrochloric acid. The aqueous phase is further extracted with ethyl acetate (3×100 ml) and then all organic fractions are combined, dried over anhydrous sodium sulphate and concentrated in vacuo. The resulting material is purified by column chromatography on silica gel to afford 2-(3,5-dimethylbiphenyl-4-yl)-3-methoxy cyclopent-2-enone (0.7 g) as a white solid.
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