[Li]CCCC.Br[C:7]1[CH:12]=[CH:11][C:10]([CH3:13])=[CH:9][CH:8]=1.[CH3:14][C:15]1([CH3:22])[CH2:20][C:19](=[O:21])[CH2:18][CH2:17][O:16]1>C1COCC1>[CH3:14][C:15]1([CH3:22])[CH2:20][C:19]([C:7]2[CH:12]=[CH:11][C:10]([CH3:13])=[CH:9][CH:8]=2)([OH:21])[CH2:18][CH2:17][O:16]1n-BuLi (26.3 ml, 1.6 M in hexane, 42 mmol) was added dropwise to a solution of 4-bromo-toluene (7.70 g, 45 mmol) in THF (100 ml) at −78° C. under N2. The resulting mixture was stirred at −78° C. for 30 min and a solution of tetrahydro-2,2-dimethyl-4H-pyran-4-one (3.84 g, 30 mmol) in THF (20 ml) was added. The resulting mixture was stirred at −78° C. for another 20 min and quenched by adding MeOH (10 ml). The reaction was concentrated under vacuum and the resulting residue was diluted with EtOAc (500 ml) and washed with sat. NH4Cl (250 ml), brine (250 ml), dried and concentrated to give 2,2-dimethyl-4-(4-methylphenyl)oxan-4-ol as a white solid, which was used without further purification (5.41 g, 82%).
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