——————————— *Corresponding author. E-mail: nfyang@xtu.edu.cn Received August 13, 2012; accepted September 6, 2012. Supported by the National Natural Science Foundation of China(No.20972131), the Research Foundation for Doctors, University of South China(No.2011XQD55) and the Natural Science Foundation of Xiangtan University, China(No.10XZX08). © Jilin University, The Editorial Department of Chemical Research in Chinese Universities and Springer-Verlag GmbH 73―74 °C. Anal.(%) calcd. for C16H14: C 93.16, H 6.84; found: C 93.14, H 6.85. 1H NMR(CDCl3), δ: 7.35(d, J=7.2 Hz, 2H, Ar―H), 7.11―7.20(m, 6H, Ar―H), 5.41(s, 2H, =CH2), 3.14(s, 4H, CH2CH2), 13C NMR(CDCl3), δ: 151.83, 141.16, 138.35, 128.88, 128.14, 127.66, 126.17, 117.43, 33.28. 2.2.2 Synthesis of 9-Ethylfluoren-9-yl Bromomethane(1d) To a solution of 9-ethylfluorene[17](9.70 g, 0.05 mol) in THF(50 mL) was dropped n-BuLi solution in hexane(20.0 mL, 2.5 mol/L) at 0 °C with stirring under nitrogen atmosphere. A solution of dibromomethane(0.05 mol) in dried THF(5 mL) was added dropwise to the solution at –10 °C with stirring within 20 min. The mixture was washed with water(5 mL×3) and the organic layer dried over anhydrous Na2SO4. The solvent was evaporated in vacuo and the residue was recrystallized from ethanol to obtain 12.10 g of 9-ethylfluoren-9-yl bromomethane. Yield 84.2%, white crystal, m. p. 70―71 °C. Anal.(%) calcd. for C16H15Br: C 66.91, H 5.26, Br 27.82; found: C 66.87, H 5.32. 1H NMR(CDCl3), δ: 7.76(d, J=7.4 Hz, 2H, Ar―H), 7.52(d, J=7.3 Hz, 2H, Ar―H), 7.34―7.44(m, 6H, Ar―H), 3.76(s, 2H, CH2Br), 2.23(q, J=7.3 Hz, 2H, CH2), 0.43(t, J=7.3 Hz, 3H, CH3). 13C NMR(CDCl3), δ: 147.43, 141.08, 127.93, 127.20, 123.55, 119.96, 55.05, 41.86, 29.86, 8.57. 2.2.3 General Procedure for Synthesis of Epoxides To a solution of compound 1a(or 1b, 1c)(2.5 mmol) in THF(100 mL) was syringed RLi solution(2.5 mmol) at –10 °C with stirring under nitrogen atmosphere. The mixture was stirred at room temperature for 2 h to give a dark red solution of organiclithium. (R)-epichlorohydrin[(R)-ECH, 1.2 mL] in dry THF(10 mL) was added dropwise to the above solution at –70 °C with stirring within 20 min. The mixture was warmed to room temperature and stirred for 3 h before distilled water(10 mL) was added. The mixture was extracted with diethyl ether(15 mL×2). The combined extract was washed with water and dried over anhydrous Na2SO4. The solvent was removed under reduce pressure and the residue was separated by column chromatography [V(elution hexane)/V(CH2Cl2)=5:1] to obtain (R)-2a[or (R)-2b, (R)-2c]. If the(R)-ECH was replaced by (S)-ECH, (S)-2a [or(S)-2b, (S)-2c] was procured.
