[O:1]([C:3]1[CH:15]=[CH:14][C:6]([C:7]([CH2:9][CH2:10][C:11]([OH:13])=[O:12])=[O:8])=[CH:5][CH:4]=1)C.O>II>[OH:1][C:3]1[CH:4]=[CH:5][C:6]([C:7]([CH2:9][CH2:10][C:11]([OH:13])=[O:12])=[O:8])=[CH:14][CH:15]=1The methoxy derivative, Compound 3.2 (14.54 g, 70 mmol), was dissolved in iodine free hydriodic acid (150 mL) and refluxed at 140° C. for four hours. After the resulting brown solution was cooled to room temperature, water was added and the mixture was neutralized. The aqueous phase was then washed with ether; the organic layers were combined, decolorized, dried and evaporated. The remaining residue was purified by flash silica chromatography to yield a white solid (11.93 g, 88%). NMR (CDCl3) δ 8.20 (d, 2H), 7.02 (d, 2H), 3.32 (t, 2H), 2.88 (d, 2H).
Wird geladen…