[C:1]([O:4][CH2:5]/[C:6](/[C:16]1[CH:21]=[CH:20][C:19]([S:22]([CH3:25])(=[O:24])=[O:23])=[CH:18][CH:17]=1)=[C:7](/[C:10]1[CH:15]=[CH:14][CH:13]=[CH:12][CH:11]=1)\[CH:8]=[O:9])(=[O:3])[CH3:2].CC(=CC)C.[O-:31]Cl=O.[Na+]>CC(O)(C)C.O>[C:1]([O:4][CH2:5]/[C:6](/[C:16]1[CH:17]=[CH:18][C:19]([S:22]([CH3:25])(=[O:24])=[O:23])=[CH:20][CH:21]=1)=[C:7](/[C:10]1[CH:15]=[CH:14][CH:13]=[CH:12][CH:11]=1)\[C:8]([OH:31])=[O:9])(=[O:3])[CH3:2]To a solution of the aldehyde from Example 3 (160 mg) and 2-methyl-2-butene (6 mL) in 2-methyl-2-propanol (35 mL) was added a solution of NaClO2 (1 g) and NaH2PO4 (1 g) in 10 mL of H2O. The mixture was stirred for 2 h at r.t., and concentrated. The residue was then taken into 50 mL of pH 7 buffer solution (1M) and extracted with EtOAc (50 mL). The extract was dried over MgSO4 and concentrated. The residue was purified by flash chromatography, eluting with 3:1 EtOAc/hexane containing 1% HOAc to give 150 mg of the title compound as a white solid.
Wird geladen…