[CH2:1]([C@H:8]([CH2:12][CH:13]=[CH2:14])[C:9]([OH:11])=[O:10])[CH2:2][CH2:3][CH2:4][CH2:5][CH2:6][CH3:7].[I:15]I>C1COCC1.O.CCOCC>[CH2:1]([C@@H:8]1[CH2:12][C@H:13]([CH2:14][I:15])[O:10][C:9]1=[O:11])[CH2:2][CH2:3][CH2:4][CH2:5][CH2:6][CH3:7]To a solution of 7.14 g (0.036 mol) of the product of Example 5 in 750 mL of THF/H2O (2:1), cooled to 0 degrees, was added 7.22 g (0.072 mol) of KHCO3 followed by 11.97 g (0.072 mol) of KI and then 18.30 g (0.072 mol) of iodine. The reaction was allowed to warm to room temperature and stirred for 18 h. The resulting mixture was diluted with ether and the organic layer was washed with aqueous sodium bisulfite solution, H2O and brine, dried over MgSO4, filtered and concentrated in vacuo. The residue was chromatographed on silica gel eluting with ethyl acetate/hexanes (1:10) to provide 8.30 g (71%) of the title compound and 3.36 g (29%) of the corresponding iodo-trans lactone as white solids. CI Mass Spec: 325.3 (M+H).
Wird geladen…
