[CH3:1][CH:2]([CH2:5][CH2:6][CH:7]1[CH2:11][CH:10]=[C:9]([CH3:12])[C:8]1([CH3:14])[CH3:13])[CH:3]=[O:4].[CH3:15][Li].S([O-])([O-])(=O)=O.[Na+].[Na+].O>C(OCC)C>[CH3:1][CH:2]([CH2:5][CH2:6][CH:7]1[CH2:11][CH:10]=[C:9]([CH3:12])[C:8]1([CH3:13])[CH3:14])[CH:3]([OH:4])[CH3:15]A solution of 20.8 g (0.12 mole) of 2-methyl-4-(2,2,3-trimethylcyclopent-3-en-1-yl)butanal dissolved in ethyl ether-anhydrous (50 ml) was added to a stirred solution of methyllithium (1.7 M) in ethyl ether (250 ml; 0.14 mole) which was previously cooled to 0° C. The mixture was stirred at 0°-5° C for 1.0 hour and then heated at reflux (36° C) for 3.0 hours. The mixture was cooled to 0° C and excess methyllithium was decomposed by slow dropwise addition of saturated sodium sulfate solution (50 ml). The mixture was poured into 150 ml of water, the lower aqueous layer was drawn off and extracted twice with 100 ml of ether. The ether extracts were combined, washed with 150 ml of brine, dried over sodium sulfate, filtered and the solvent removed by distillation. The residual oil was fractionally distilled to yield 3-methyl-5-(2,2,3-trimethylcyclopent-3-en-1-yl)pentan-2-ol: 20.4 g (81% yield); bp 96°-98° (0.9 mm); mol wt. 210 (ms).
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