反应详情

(5R)-7-Oxo-3-vinyl-4-oxa-1-azabicyclo[3.2.0] hept-2-ene (2.5 mmole) in dry tetrahydrofuran (20 ml) was treated with 2-mercaptoethanol (0.4 ml) and benzoyl peroxide (10 mg). The resulting mixture was stirred under dry nitrogen while being irradiated using a 200 W bulb placed 1" from the reaction vessel for a total time of 14 hours. The mixture was diluted with ethyl acetate (100 ml) and was washed with saturated sodium bicarbonate solution and saturated brine. The solution was dried (magnesium sulphate) and the solvent was evaporated under reduced pressure to give a yellow oil. The oil was chromatographed on silica gel (20 g) using graded elution from 1:4 to 1:1 ethyl acetate/petroleum ether (b.p. 60°-80°). The title compound was thus obtained as a colourless gum (45 mg), [α]D22 =+66.8° (c 1.0, CHCl3). νmax (CHCl3): 3370, 1795, 1695 cm-1. δ(CDCl3): 2.40 (1H, br.s, OH), 2.65 (2H, t, J 6 Hz), 2.95 (1H, d, J 16 Hz), 3.15-3.80 (6H, complex), 4.25-4.55 (2H, complex), 5.47 (1H, d, J 2 Hz). m/e: 138 (67%), 96 (100).

1. customwhile being irradiated
2. customfor a total time of 14 hours
3. washwas washed with saturated sodium bicarbonate solution and saturated brine
4. dry with materialThe solution was dried (magnesium sulphate)
5. customthe solvent was evaporated under reduced pressure
6. customto give a yellow oil
7. customThe oil was chromatographed on silica gel (20 g)
8. washelution from 1:4 to 1:1 ethyl acetate/petroleum ether (b.p. 60°-80°)