反应详情

To a solution of 4-[2-(5-methyl-2-phenyl-4-oxazolyl)ethoxy]benzaldehyde (3.59 g, 11.7 mmol) synthesized according to the method described in WO95/18125 in toluene (40 ml) were added 4-nitrobenzyl isopropyl malonate (4 g, 14 mmol) obtained in Step 1, acetic acid (351 mg) and piperidine (498 mg). While removing water through Dean-Stark trap, the mixture was refluxed under heating. Two hours later, toluene was evaporated under reduced pressure. The obtained residue was purified by silica gel column chromatography (developing solvent; hexane:ethyl acetate=65:35) and the fraction containing the objective substance was concentrated under reduced pressure to give the title compound (5.24 g, yield 66%) as a yellow oil.

1. customWhile removing water through Dean-Stark trap
2. temperaturethe mixture was refluxed
3. temperatureunder heating
4. customTwo hours later, toluene was evaporated under reduced pressure
5. customThe obtained residue was purified by silica gel column chromatography (developing solvent; hexane:ethyl acetate=65:35)
6. additionthe fraction containing the objective substance
7. concentrationwas concentrated under reduced pressure