Dimethyl Sulfate → 4-Pentylcyclohexanol methyl ether

Under argon, to a solution of 4-pentylcyclohexanol (2.0 g, 11.75 mmol) in anhydrous THF (60 mL), NaH was added (60%, 0.94 g, 23.5 mmol) at 0° C. and stirred for 30 minutes, followed by the addition of dimethyl sulfate (1.68 mL, 17.62 mmol). The mixture was refluxed for 12 hrs and cooled to 0° C. The reaction was quenched with saturated ammonium chloride solution (20 mL). THF was removed under vacuum and the residue was extracted with CH2Cl2 (3×25 mL). The collected organic portion was dried with Na2SO4 and concentrated. The crude product was purified by flash chromatography (hexanes/ethyl acetate: 15/1) to provide probe 1 (2.0 g, quant.) as a colorless liquid. 1H NMR (400 MHz, CDCl3): δ=0.79-0.85 (m, 10 H), 1.28-1.38 (m, 7 H), 1.46 (br, 2 H), 2.02 (br, 2 H), 3.32 (s, 3 H). 13C NMR (100 MHz, CDCl3): δ=8.1, 20.9 (2 carbons), 24.1 (2 carbons), 30.2 (2 carbons), 32.6, 34.8, 45.2, 55.5, 74.8; MS (ESI) calcd for C12H25O [M+H]+/z: 185.19. found: 185.31.