Tetrahydrofuran → Benzhydryl (E)-(2S,3S,5R)-3-(2-ethoxycarbonyl-propenyl)-3-methyl-7-oxo-4-thia-1-aza-bicyclo[3.2.0]heptane-2-carboxylate

関与物質

反応条件

反応手順

286 mg (0.75 mmol) of benzhydryl (2S,3R,5R)-3-formyl-3-methyl-7-oxo-4-thia-1-aza-bicyclo[3.2.0]heptan-2-carboxylate were dissolved in 12 ml of THF under argon and treated with 271 mg (0.75 mmol) of (1-ethoxycarbonylethylidene)-triphenylphosphorane. The yellow solution was stirred at 70° C. for 6 hours and subsequently concentrated. The residue remaining behind was chromatographed over silica gel (0.040-0.063 mm particle size) with ethyl acetate:hexane (9:16) as the eluent. Yield: 157 mg (45%) of pale yellow solid IR (film): 1788, 1754, 1704, 1642 cm-1MS: (M+NH4+) 483.4 1H-NMR (400MHz, CDCl3): δ[ppm]=1.32(t,3H,J=7.1 Hz),1.38(s,3H), 2.03(d,3H,J=1.5Hz), 3.05(dd,1H,J=1.8Hz, 16Hz,6-H), 3.57(dd,1 H, J=4.3Hz, 16Hz,6-H), 4.23(q,2H,J=7.1Hz), 4.89(s,1H,2-H), 5.29(dd, 1H,J=4.3, 1.8Hz,5-H), 6.94(s,1H,CHPh2), 7.20(d,1H,J=1.5Hz,=CH), 7.30-7.36(m,10H,Ph).

情報源と証拠