反应详情

温度

-10 °C

To a solution of alcohol 3 (0.8 g, 4.7 mmol) in diethyl ether (5 ml) NaH (0.22 g of a 55% dispersion in mineral oil (0.22 mmol)) was added. The reaction mixture was cooled to −10° C. and a solution of trichloroacetonitrile (0.68 g, 4.7 mmol) in diethyl ether (3 ml) was added dropwise. The solution was allowed to warm to room temperature and the solvent evaporated. Pentane (8 ml) containing methanol (0.018 ml) was added to the residue. The resulting mixture was filtered through a pad of celite and evaporated. The residual oil was dissolved in xylene (10 ml) and refluxed for 10 h. Main amount of xylene was distilled off at reduced pressure (11 mm Hg) and the residue purified by flash chromatography on silica gel (hexane, hexane-ethyl acetate, 10:1) to give 4 (0.98 g, 66%) as an oil. 1H NMR (CDCl3, TMS): 0.95 (6H, s, 3,5-CH3); 1.18 (6H, s, 3,5-CH3); 1.1-1.5 (2H, m, 4-CH2); 1.32 (2H, d, 15 Hz, 2,6-CH2); 2.15 (2H, d, 15 Hz, 2,6-CH2); 5.08 (1H, d, 11 Hz, ═CH2); 5.13 (1H, d, 18 Hz, ═CH2); 5.85 (1H, dd, 18 and 11 Hz, —HC═) and 6.7 ppm (1H, br s, NH).

1. temperatureto warm to room temperature
2. customthe solvent evaporated
3. additionPentane (8 ml) containing methanol (0.018 ml)
4. additionwas added to the residue
5. filtrationThe resulting mixture was filtered through a pad of celite
6. customevaporated
7. dissolutionThe residual oil was dissolved in xylene (10 ml)
8. temperaturerefluxed for 10 h
9. distillationMain amount of xylene was distilled off at reduced pressure (11 mm Hg)
10. customthe residue purified by flash chromatography on silica gel (hexane, hexane-ethyl acetate, 10:1)