反应详情

温度

0 °C

To a mixture of 5-tert-butyl-1,3-oxazole-2-carbohydrazide (15 g, 82 mmol) in diethyl ether (250 mL) at 0° C. are added 6N aqueous HCl solution (210 mL, 1.26 mol) and NaNO2 (9.6 g, 139 mmol) aqueous solution over a period of 15 min. The reaction mixture is stirred at 0° C. for 1 h and saturated NaHCO3 solution is added to quench the reaction. The mixture is extracted with diethyl ether (3×100 mL) and the ether layers are combined, washed with brine, dried (Na2SO4) and concentrated. The residue is diluted with xylene (70 mL) and benzyl alcohol (27 g, 246 mmol) is added. The reaction mixture is refluxed for another 3 h and the solvent is removed under vacuum. The residue is purified by flash column chromatography to afford the title compound (5.0 g, 22%).

1. customto quench
2. customthe reaction
3. extractionThe mixture is extracted with diethyl ether (3×100 mL)
4. washwashed with brine
5. dry with materialdried (Na2SO4)
6. concentrationconcentrated
7. additionis added
8. temperatureThe reaction mixture is refluxed for another 3 h
9. customthe solvent is removed under vacuum
10. customThe residue is purified by flash column chromatography