[CH3:1][O:2][CH:3]1[C:11]2[C:6](=[C:7]([CH2:12][CH2:13]O)[CH:8]=[CH:9][CH:10]=2)[CH2:5][CH:4]1[CH3:15].C1C=CC(P(C2C=CC=CC=2)C2C=CC=CC=2)=CC=1.C1COCC1.C1C(=O)N([Br:47])C(=O)C1>>[Br:47][CH2:13][CH2:12][C:7]1[CH:8]=[CH:9][CH:10]=[C:11]2[C:6]=1[CH2:5][CH:4]([CH3:15])[CH:3]2[O:2][CH3:1]To a mixture of 41.3 g (0.2 mol) of 2-(1-methoxy-2-methyl-2,3-dihydro-1H-inden-4-yl)ethanol and 52.5 g (0.2 mol) PPh3 in 800 ml of THF 35.6 g (0.2 mol) of NBS was added at vigorous stirring for 5 min at 0° C. This mixture was stirred for 2 h at room temperature and then evaporated to dryness. A solution of the residue in 500 ml of hexanes was filtered through glass frit (G3), and the precipitate was additionally washed by 3×300 ml hexanes. The combined organic extract was evaporated to dryness. The product was isolated from the residue using flash chromatography on Silica Gel 60 (40-63 um, d 80 mm, l 250 mm; eluent: hexanes/ether=20/1, vol.). Yield 39.3 g (73%) of ca. 1 to 1 mixture of the diastereomers A and B.
Wird geladen…
