Acetic Acid → Isopropyl 4-nitrobenzyl 2-[4-[2-(5-methyl-2-phenyl-4-oxazolyl)ethoxy]benzylidene]malonate

Participants

Reaction Steps

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.

Provenance & Evidence