Under argon protection, octadecyl diethyl phosphite (1.2 g) was added to a Schlenk flask with 10 mL of dichloromethane. TMSBr (2.0 g, 4 mmol) was added slowly via syringe and the reaction mixture was stirred overnight at room temperature. The following day, dichloromethane and unreacted TMSBr were removed by distillation under reduced pressure. 15 mL of methanol was added to the residue and stirring was continued for 3 hr. Subsequently, methanol was evaporated under reduced pressure to give an off-white crystalline solid. The crude product was dissolved in boiling hexane with vigorous stirring and left to partition, cooled to room temperature and filtered. This purification process was repeated three times for complete removal of oily impurities, resulting in a white solid product. The product was characterized as follows: 1H NMR (CDCl3, ppm, J Hz): δ 8.73 (br, 2H, OH), 1.90 (m, 2H, PCH2, J = 26.75), 1.616 (br, 2H, CH2), 1.39 (br, 2H, CH2), 1.19 (s, 30H, CH2-alkyl), 0.877 (t, 3H, CH3, J = 13.0). Mass spectrum: [M+] = 334.26. Elemental analysis: C18H39O3P, calculated values: C, 64.64; H, 11.75; measured values: C, 64.62; H, 11.72.
