[CH3:1][C:2]1([CH3:11])[CH2:7][CH2:6][CH:5]([CH2:8][CH2:9]O)[CH2:4][CH2:3]1.[BrH:12]>S(=O)(=O)(O)O>[Br:12][CH2:9][CH2:8][CH:5]1[CH2:6][CH2:7][C:2]([CH3:11])([CH3:1])[CH2:3][CH2:4]1A mixture of 2-(4,4-dimethylcyclohexyl)ethanol (WO99/59971) (2 g, 12.8 mmol), concentrated sulphuric acid (750 μl) and 48% hydrobromic acid (3 ml) was stirred at 90° C. for 7 hours. The cooled mixture was then carefully quenched by the addition of water (25 ml), and the mixture was extracted with dichloromethane (3×30 ml). The combined organic extracts were washed with 2M sodium carbonate solution and brine (30 ml), then dried (MgSO4) and concentrated under reduced pressure. The residual black gum was purified by distillation to afford the title compound, 330 mg. 1H-NMR (CDCl3, 400 MHz) δ: 0.82 (2×s, 6H), 1.02-1.20 (m, 4H), 1.35 (m, 3H), 1.50 (m, 2H), 1.78 (m, 2H), 3.40 (t, 2H).
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