[Synthesis]
4-(4-Hydroxyphenyl)cyclohexanone (5.0 g, 26.3 mmol) and ethyl iodide (10.5 mL, 20.5 g, 131 mmol, 5 eq.) in acetone (100 mL) were added as a base with K2CO3 (14.5 g, 105 mmol, 4 eq.). The reaction mixture was heated to 65 °C and stirred overnight. After completion of the reaction, the solvent was removed by distillation under reduced pressure. The residue was dissolved in water and extracted with EtOAc. The organic phases were combined, washed with brine, dried over anhydrous Na2SO4, filtered and concentrated under reduced pressure to give spectrally pure 4-(4-ethoxyphenyl)cyclohexanone (5.74 g, 100% yield). The product was confirmed by 1H NMR (CDCl3): δ 7.15 (dt, 2H), 6.86 (dt, 2H), 4.02 (q, 2H), 2.99 (tt, 1H), 2.46-2.54 (m, 4H), 2.16-2.24 (m, 2H), 1.83-2.00 (m, 2H), 1.41 (t, 3H). The mass spectrum (electrospray) showed an m/e of 219 (M + 1)+, consistent with the calculated molecular weight of 218 for C14H18O2. |