[CH3:1][C:2]1([CH3:9])[CH2:7][CH2:6][C:5](=[O:8])[CH:4]=[CH:3]1.[CH3:10][Li]>C(OCC)C>[CH3:10][C:5]1([OH:8])[CH2:6][CH2:7][C:2]([CH3:9])([CH3:1])[CH:3]=[CH:4]1To a stirred solution of 4,4-dimethylcyclohex-2-enone (40.0 g, 322 mmol) in anhydrous diethyl ether (400 mL) at −78° C. was added an ethereal solution of methyllithium (220 mL of a 1.6 M). The resulting solution was allowed to warm to room temperature, stirred for 18 hours. The reaction was quenched by the addition of water (200 mL). The phases were separated and the aqueous layer extracted with diethyl ether (2×200 mL). The combined organic phase was washed with water (2×200 mL), dried over anhydrous sodium sulfate and concentrated under reduced pressure to give the title compound as clear, light yellow oil (41 g, Yield: 90%). Rf 0.5 (5:1 petroleum ether/ethyl acetate); 1H NMR (400 MHz, CDCl3) δ 5.46 (d, J=10.0 Hz, 1H), 5.43 (d, J=10.0 Hz, 1H), 1.73-1.70 (m, 2H), 1.59-1.56 (m, 1H), 1.50-1.45 (m, 1H), 1.27 (s, 3H), 1.01 (s, 3H), 0.95 (s, 3H) ppm; Mass spectrum (ESI +ve) m/z 123 (M−H2O+H+).
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