反应详情

温度

25 °C

To 60% sodium hydride (336 mg, 10.0 mmol) in toluene (20 mL) at 0° C. was added dropwise a solution of 5-vinylpyrrolidin-2-one (1.0 mg, 9.0 mmol) in toluene (10 mL) over a 10 min period. The cooling bath was removed and the solution was allowed to warm to 25° C. to ensure complete generation of the anion. To the anion at 25° C. was added dropwise a solution of (2S)-2-benzoylpropanoyl chloride (21, 2.7 g, 12.6 mmol) in toluene (10 mL) over a 10 min period. TLC indicated that the reaction was complete upon addition of the acid chloride (silica gel plates; hexane and t-butyl methyl ether, 1:1). Water (50 mL) as added to the reaction mixture and the phases were separated. The aqueous phase was extracted with diethyl ether (2×40 mL). The combined organic phases were washed with a saturated aqeous sodium bicarbonate solution (1×100 mL) and dried (MgSO4). Concentration and purification by flash chromatography on silica gel (EM 60, 0.040-0.063 partical size, 230-400 Mesh, column size: 6.5 cm diameter×20 cm length) using hexane and t-butyl methyl ether (10:1) afforded 1.1 g (42%) of (5S)-N-((2S)-2-benzoylpropanoyl)-5-ethenylpyrrolidin-2-one (24a) as a thick oil: 1H NMR (CDCl3) δ1.44-1.46 (d, J=6.5 Hz ,3 H), 1.64-1.80 (m, 1 H), 2.12-2.20 (m, 1 H), 2.42-2.84 (m, 2 H), 4.12-4.21 (q, J=6.4 Hz, 1 H), 4.38-4.47 (m, 1 H), 4.58-4.67 (m, 1 H), 4.89-4.91 (m, 1 H), 5.06-5.19 (m, 2 H), 5.77-5.85 (m, 1 H), 7.28-7.40 (m, 5 H); 13C NMR (CDCl3) δ174.8, 173.5, 137.7, 135.3, 128.0, 127.7, 127.4, 115.1, 74.6, 71.6, 31.3, 24.0, 18.1; IR (neat) 3066 (w), 3033 (w), 2939 (w), 1740 (vs), 1708 (vs), 1455 (s), 1370 (s), 1277 (s), 1148 (s), 1113 (s), 739 (s) cm-1.

1. customThe cooling bath was removed
2. customthe phases were separated
3. extractionThe aqueous phase was extracted with diethyl ether (2×40 mL)
4. washThe combined organic phases were washed with a saturated aqeous sodium bicarbonate solution (1×100 mL)
5. dry with materialdried (MgSO4)
6. concentrationConcentration and purification by flash chromatography on silica gel (EM 60, 0.040-0.063 partical size, 230-400 Mesh, column size: 6.5 cm diameter×20 cm length)