[CH:1]1[C:13]2[CH2:12][C:11]3[C:6](=[CH:7][CH:8]=[CH:9][CH:10]=3)[C:5]=2[CH:4]=[CH:3][CH:2]=1.C([Li])CCC.Br[CH2:20][CH2:21][CH:22]1[O:26][CH2:25][CH2:24][O:23]1.CCCCCC.C(OCC)(=O)C>C1COCC1>[CH:1]1[C:13]2[CH:12]([CH2:20][CH2:21][CH:22]3[O:26][CH2:25][CH2:24][O:23]3)[C:11]3[C:6](=[CH:7][CH:8]=[CH:9][CH:10]=3)[C:5]=2[CH:4]=[CH:3][CH:2]=12-(9-Fluorenyl)ethyl-1,3-dioxolane was prepared from a solution of fluorene (30.0 g, 180.5 mmol) in 400 ml of dry THF cooled in a -78° C. bath under argon, to which was added 100 ml of n-butyllithium (2.0M in cyclohexane) over 15 minutes After stirring for 0.5 hours at 78° C. 2-(2-bromoethyl)-1, 3-dioxolane (22.3 ml, 190 mmol) was added dropwise, and the resulting solution stirred at room temperature for 16 hours. Concentration in vacuo yielded an orange residue which was partitioned between ethyl acetate and saturated ammonium chloride. The organic layer was then washed with brine, dried with magnesium sulfate, and concentrated in vacuo to afford an orange oil. Flash chromatography on silica, hexane:ethyl acetate 20:1 to 1:1 yielded a yellow oil (36.38 g, 76%).
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