[BH4-].[Na+].[OH:3][CH:4]([CH:10]1[CH2:14][CH2:13][O:12][CH:11]1[O:15][CH:16]([CH3:18])[CH3:17])[C:5](OCC)=[O:6].Cl.N(CCO)CCO>C(O)C.O>[CH:16]([O:15][CH:11]1[CH:10]([CH:4]([OH:3])[CH2:5][OH:6])[CH2:14][CH2:13][O:12]1)([CH3:18])[CH3:17]In a 2 L round bottom flask charged with 600 mL of ethanol and NaBH4 (12.55 g, 0.33 mol, 1.1 eq.) at 0° C., ethyl hydroxy-(2-isopropoxytetrahydro-3-furanyl)acetate (70 g, 0.3 mol, 1 eq.) dissolved in 400 mL of ethanol was added dropwise over 1 hour at 0° C. The mixture was allowed to warm up at room temperature and stirred for 19 hours. After cooling at 0° C., diethanolamine hydrochloride (46.7 g, 0.33 mol, 1.1 eq.) dissolved in 100 mL of water was added over 10 min. and stirred for 8 hours. The solvent was evaporated under reduced pressure to afford a clear yellow solid. After dilution with 300 mL of ethylacetate, the heterogeneous mixture was filtered over dicalite. The mixture was used directly in the next step.
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