[O:1]1[CH2:6][CH2:5][CH2:4][CH2:3][CH:2]1[O:7][CH2:8][C@H:9]1[O:13][C:12](=[O:14])[CH2:11][CH2:10]1.[CH3:15][CH2:16][Mg+].[Br-].CCOCC>C1COCC1.CC(O[Ti](OC(C)C)(OC(C)C)OC(C)C)C>[OH:13][C@H:9]([CH2:8][O:7][CH:2]1[CH2:3][CH2:4][CH2:5][CH2:6][O:1]1)[CH2:10][CH2:11][C:12]1([OH:14])[CH2:16][CH2:15]1To a mixture of Ti(OiPr)4 (0.33 mL, 0.001 mol, Ardrich) and (5S)-5-((tetrahydro-2H-pyran-2-yloxy)methyl)-dihydrofuran-2(3H)-one (1.0 g, 0.005 mol) in 18.7 mL of THF was added a solution of 3M EtMgBr in Et2O (4.3 mL, 0.0125 mol, Aldrich) via a syringe over 3 hrs at 15° C. After stirring for additional one hour at 15° C., the reaction was quenched with 20 mL of saturated NH4Cl solution, filtered and extracted with EtOAc (50 mL×2). The combined organic phases were dried over Na2SO4 and concentrated in vacuo. The residue was purified by a silica gel column chromatography to afford 1-((S)-3-hydroxy-4-(tetrahydro-2H-pyran-2-yloxy)butyl)cyclopropanol as colorless oil (0.853 g, 74%)2.
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