反应详情

A mixture of 3-(5-amino-1,3,4-oxadiazol-2-yl)pentan-3-ol (0.446 g, 2.6 mmol) and 4-(4-fluorophenyl)-2-oxo-2H-chromene-7-carbaldehyde (0.350 g, 1.3 mmol) in 5 mL of toluene was refluxed with a Dean-Stark trap overnight. After cooling to rt the solvent was removed and the crude imine diluted in ethanol (8 ml) at 0° C. Solid NaBH4 (49 mg) was added to the solution and after 30 min of stirring aqueous NH4Cl was added to destroy the excess hydride. After dilution with EtOAc-brine, the organic phase was dried with MgSO4. Purification on silica gel with toluene-EtOAc (2:8) gave the title compound. 1H NMR (400 MHz, acetone-d6): δ 7.67 (m, 2H), 7.48 (m, 2H), 7.37 (m, 3H), 7.19 (bt, 1H), 6.33 (s, 1H), 4.66 (m, 2H), 4.31 (s, 1H), 1.85 (m, 4H), 0.85 (t, 6H).

1. temperaturewas refluxed with a Dean-Stark trap overnight
2. customwas removed
3. additionthe crude imine diluted in ethanol (8 ml) at 0° C
4. additionSolid NaBH4 (49 mg) was added to the solution and after 30 min of stirring aqueous NH4Cl
5. additionwas added
6. customto destroy the excess hydride
7. dry with materialAfter dilution with EtOAc-brine, the organic phase was dried with MgSO4
8. customPurification on silica gel with toluene-EtOAc (2:8)