[O:1]([CH:9]1[CH2:13][C:12](=[O:14])[CH:11]=[CH:10]1)[Si:2]([C:5]([CH3:8])([CH3:7])[CH3:6])([CH3:4])[CH3:3].[H-].[Al+3].[Li+].[H-].[H-].[H-].[OH-].[Na+]>[Cl-].[Cl-].[Zn+2]>[Si:2]([O:1][C@@H:9]1[CH2:13][C@H:12]([OH:14])[CH:11]=[CH:10]1)([C:5]([CH3:8])([CH3:7])[CH3:6])([CH3:4])[CH3:3]A stirred solution of ZnCl2 (19 mL, 19 mmol, 1M in ether) is treated with 4-tert-butyldimethylsiloxy-2-cyclopentenone (2.0 g, 9.42 mmol) under an atmosphere of argon. The solution is cooled to -20° C. and treated dropwise with lithium aluminum hydride (9.0 mL, 9.0 mmol, 1M in ether) at such a rate as to keep the reaction temperature at or below -15° C. After stirring for about 2 hours at -20° C., approximately 5 mL of 1N NaOH was added. The reaction is filtered through diatomaceous earth, dried over anhydrous magnesium sulfate, filtered and concentrated under vacuum to provide the title compound (1.3 g); cis/trans/1-2+1-4 addition 81/3/16.
Wird geladen…
