[C:1]1([C:7]2[N:8]=[CH:9][O:10][C:11]=2[C:12]2[CH:17]=[CH:16][CH:15]=[CH:14][CH:13]=2)[CH:6]=[CH:5][CH:4]=[CH:3][CH:2]=1.[Li]CCCC.[CH3:23][O:24][C:25]1[C:26]([CH3:39])=[C:27]([CH:36]=[CH:37][CH:38]=1)[CH2:28][CH:29]1[CH2:34][CH2:33][CH2:32][CH2:31][C:30]1=O.Cl>C1COCC1>[CH3:23][O:24][C:25]1[C:26]([CH3:39])=[C:27]([CH:36]=[CH:37][CH:38]=1)[CH2:28][CH:29]1[CH2:34][CH2:33][CH2:32][CH:31]=[C:30]1[C:9]1[O:10][C:11]([C:12]2[CH:13]=[CH:14][CH:15]=[CH:16][CH:17]=2)=[C:7]([C:1]2[CH:6]=[CH:5][CH:4]=[CH:3][CH:2]=2)[N:8]=1To a solution of 4,5-diphenyloxazole (990 mg) in THF (15 ml) was added n-BuLi (1.56M solution in hexane, 2.87 ml) at −60° C. and stirred for 1 hour. To the mixture was added a solution of 2-(3-methoxy-2-methylbenzyl)cyclohexanone (945 mg) in THF (4 ml), warmed to 5° C., and stirred for 2 hours. To the reaction mixture was added 1N HCl and extracted with EtOAc. The organic layer was washed with water, saturated sodium hydrogen carbonate, water, and brine, dried over magnesium sulfate, evaporated in vacuo. The residue was dissolved in toluene (45 ml) and p-TsOH.H2O (79 mg) was added. The mixture was refluxed for 48 hours, cooled to room temperature, diluted with EtOAc, washed with saturated sodium hydrogen carbonate, water, and brine, dried over magnesium sulfate, evaporated in vacuo. The residue was purified by silica gel column chromatography (hexane-EtOAc 15:1 to 10:1) to give 2-[1-(3-methoxy-2-methylbenzyl)-2-cyclohexen-2-yl]-4,5-diphenyloxazole (1.19 g) as an amorphous solid.
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