[Na].[CH3:2][C:3]([OH:9])([CH3:8])[CH:4]([OH:7])[CH2:5][OH:6].[C:10]1([CH3:16])[CH:15]=[CH:14][CH:13]=[CH:12][CH:11]=1>C(O)C>[CH2:16]([O:6][CH2:5][CH:4]([O:7][CH2:16][C:10]1[CH:15]=[CH:14][CH:13]=[CH:12][CH:11]=1)[C:3]([CH3:8])([OH:9])[CH3:2])[C:10]1[CH:15]=[CH:14][CH:13]=[CH:12][CH:11]=1.[CH2:16]([O:6][CH2:5][CH:4]([OH:7])[C:3]([CH3:8])([OH:9])[CH3:2])[C:10]1[CH:15]=[CH:14][CH:13]=[CH:12][CH:11]=1A solution of 0.460 g of sodium in 10 ml of ethanol is treated with 2.4 g of (RS)-3-methyl-1,2,3-butanetriol. 20 ml of toluene are added thereto and, with the simultaneous dropwise addition of 60 ml of toluene, solvent is distilled off slowly until the distillate amounts to 75 ml. The residual suspension is suction filtered, the residue is washed with ether and dried at room temperature/11 Torr. The salt is suspended in 10 ml of tetrahydrofuran, then 0.740 g of tetrabutylammonium iodide and 4.0 ml of benzyl bromide are added and the mixture is stirred at room temperature for 3 days. The mixture is diluted with benzene and concentrated at 30°/11 Torr. The residue is chromatographed on 30 g of silica gel with hexane/ether (4:1). There are thus obtained, besides 0.616 g of (RS)-1,2-dibenzyloxy-3-methyl-3-butanol, as the polar fraction 1.15 g of the desired product as a colourless oil of boiling point 150°/2 Torr (bulb-tube).
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