[CH2:1]([O:3][C:4](=[O:13])[C:5]1[CH:10]=[CH:9][C:8](Br)=[CH:7][C:6]=1[CH3:12])[CH3:2].[C:14]1([OH:20])[CH:19]=[CH:18][CH:17]=[CH:16][CH:15]=1.C([O-])([O-])=O.[Cs+].[Cs+].C(OCC)(=O)C>C1(C)C=CC=CC=1>[CH2:1]([O:3][C:4](=[O:13])[C:5]1[CH:10]=[CH:9][C:8]([O:20][C:14]2[CH:19]=[CH:18][CH:17]=[CH:16][CH:15]=2)=[CH:7][C:6]=1[CH3:12])[CH3:2]27.5 g of 4-bromo-2-methyl-benzoic acid ethyl ester was dissolved in 120 mL of anhydrous toluene. To the solution was added 21.3 g of phenol, 73.6 g of Cs2CO3, 551 μL of ethyl acetate, 22 g of activated 4 A molecular sieves, and 5.68 g of 90% copper(I) trifluoromethanesulfonate benzene complex. The reaction was placed under a nitrogen atmosphere and heated at reflux temperature for 48 h. The resultant mixture was partitioned between water and ethyl acetate, and the mixture filtered through a fine sintered glass filter to remove insoluble material. The organic fraction was washed three times with 1.0N NaOH, once with brine, dried over anhydrous sodium sulfate, and concentrated to 18.2 g of a pale tan liquid: 1H NMR (200 MHz, CDCl3) δ 7.93-7.88 (dd, J=1.3, 7.8 Hz, 1H) 7.39-7.30 (m, 2H), 7.19-7.10 (tt, J=1.2, 7.4 Hz, 1H), 7.06-7.7.0 (m, 2H), 6.80-6.75 (m, 2H), 4.37-4.26 (q, J=7.0 Hz, 2H), 2.56 (s, 3H), 1.40-1.33 (t, J=7.0 Hz, 3H).
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