2,3-Dihydroxybutanedioic Acid → (2S,3S)-(-)-3-[8-(methoxyethoxymethoxy)octyl]-2-hydroxymethyloxirane

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Reaction Steps

200 ml of absolute CH2Cl2 are cooled to between -25° C. and -30° C. (dry ice/methanol) in a three-neck flask which has been dried by heating and flushed with nitrogen. 20 mmol of tetraisopropyl titanate [Ti(O--i--C3H7)4 ] and 20 mmol of L-(+)-diethyl tartrate (L-(+)-DET), dissolved in 2 ml of absolute CH2Cl2, are added with stirring through a septum. After 5 to 10 minutes, 20 mmol of the allyl alcohol 4 are added, dissolved in a little absolute CH2Cl2, and finally 40 mmol of a 3.0 molar solution of tert.butyl hydroperoxide (TBHP) in toluene are added. The resultant solution is left to stand overnight at -25° C. 50 ml of a 10% strength solution of tartaric acid in water are then added with stirring at -25° C. After 30 minutes, the cooling bath is removed, and stirring is continued at room temperature until the aqueous solution separates out and is clear. The phases are separated, the organic phase is washed once with water, and the solvent is removed on a rotary evaporator. The residue is taken up in 150 ml of Et2O, and 60 ml of a precooled 1N NaOH solution are added to the resultant solution at 0° C. The two-phase system is stirred at 0° C. for 30 minutes. The phases are then separated, the etherial phase is washed once with saturated NaCl solution and dried over MgSO4, and the solvent is stripped off. The crude substance obtained is purified by flash chromatography.

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