4-Nitrobenzaldehyde → 5-(4-Nitrophenyl)-1,3-oxazole

Reaction equation

[N+:1]([C:4]1[CH:11]=[CH:10][C:7]([CH:8]=[O:9])=[CH:6][CH:5]=1)([O-:3])=[O:2].S([CH2:22][N+:23]#[C-:24])(C1C=CC(C)=CC=1)(=O)=O.C(=O)([O-])[O-].[K+].[K+]>CO>[N+:1]([C:4]1[CH:5]=[CH:6][C:7]([C:8]2[O:9][CH:24]=[N:23][CH:22]=2)=[CH:10][CH:11]=1)([O-:3])=[O:2]

Participants

Procedure

A mixture of 4-nitro-benzaldehyde (5.0 g, 33.1 mmol), tosylmethyl isocyanide (6.4 g, 33.1 mmol) and potassium carbonate (7.8 g, 82.7 mmol) in methanol (100 ml) was heated under reflux for 30 minutes. After concentrating under reduced pressure, the residue was stirred with water (50 ml). The solid that was filtered to afford 5-(4-nitro-phenyl)-oxazole (5.6 g, 89% yield). 1H NMR (acetone-d6) δ 7.89 (s, 1H, Ar), 8.05 (d, 2H, J=9.3 Hz, Ar), 8.35-8.38 (m, 3H, Ar).