[C:1]([O:4][CH:5]1[CH2:12][CH2:11][CH:10]2[CH:6]1[CH2:7][CH2:8][CH:9]2[CH2:13][OH:14])(=[O:3])[CH3:2].[Cr](Cl)([O-])(=O)=O.[NH+]1C=CC=CC=1.C(=O)(O)[O-].[Na+]>ClCCl>[C:1]([O:4][CH:5]1[CH2:12][CH2:11][CH:10]2[CH:6]1[CH2:7][CH2:8][CH:9]2[CH:13]=[O:14])(=[O:3])[CH3:2]A stirred solution of 6-acetoxy-2-hydroxymethylbicyclo[3,3,0]octane (0.10 g; prepared as described in Reference Example 20 and predominantly in the 2β-configuration) in dry dichloromethane (2.5 ml) was treated with pyridinium chlorochromate (0.22 g) and anhydrous sodium bicarbonate (0.083 g). The resulting suspension was stirred for 150 minutes at the ambient temperature and was then placed directly onto a short column of silica gel and subjected to medium pressure, short column chromatography, eluting with a mixture of ethyl acetate and toluene (1:1 v/v) to give 6-acetoxy-2-formylbicyclo[3,3,0]octane (0.070 g), predominantly in the 2β-configuration.
Wird geladen…
