3-Nitrobenzaldehyde → 4-Methyl-5-(3-nitrophenyl)-1,3-oxazole

Participants

Reaction Steps

To a cooled (0° C.) solution of 3-{[1-(isocyanoethyl)ethyl]sulfonyl}aniline (60 g, 0.287 mol) in dry MeOH (800 mL), was added dry powdered K2CO3 and stirred at rt for 1 h. The reaction mixture was re-cooled to 0° C. and 3-nitro benzaldehyde (43 g, 0.287 mol) added. The reaction mixture was warmed to rt, followed by heating at 55° C. overnight with stirring. The excess solvent was removed under reduced pressure, the residue was dissolved in water (100 mL) and extracted with EtOAc (3×350 mL). The combined organic layers were washed with brine, water, dried over anhydrous Na2SO4 and concentrated. The crude product was purified by silica get (60-120 mesh) column chromatograph using 15% EtOAc in petroleum-ether to yield product as yellow solid. Yield 50 g (86%).

Provenance & Evidence