[C:1](=[C:4]([OH:10])[C@H:5]([OH:9])[CH2:6][CH2:7]O)([CH3:3])[CH3:2].C1(P(C2C=CC=CC=2)C2C=CC=CC=2)C=CC=CC=1.[Br:30]N1C(=O)CCC1=O.CCCCCC>C(Cl)Cl>[Br:30][CH2:7][CH2:6][C@@H:5]([OH:9])[C:4](=[C:1]([CH3:3])[CH3:2])[OH:10](R)-Isopropylidenebutane-1,2,4-triol (0.3 g, 2.05 mmol) and triphenylphosphine (0.63 g, 2.4 mmol) were dissolved in methylene chloride (5 ml) and cooled to 0° C. and N-bromosuccinimide (0.38 g, 2.16 mmol) was added in small portions with stirring. After additional 1 h of stirring at 0° C. hexane (15 ml) was added and the resulting precipitate was removed by filtration and washed twice with hexane (2×5 ml). The combined hexane solution was passed through a short column of silica gel (5 g). Elution with hexane (15 ml) gave after evaporation and distillation the title compound as a colourless oil (0.2 g, 0.96 mmol, 47%): b.p. 74°-76° C. at 2.7 kPa (20 mm Hg), nD20 =1.4630. {α}D20 =+27.7° (c=20, CHCl3).
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