p-Chloroanilino-, p-acetylanilino-and p-toluidino-fumarates are oxidized by lead tetraacetate in low yields to give oxanilate. Similar oxidation of p-acetylanilinofumarate in the presence of trifluoroacetic acid affords only oxanilate. p-Toluidino and p-chloroanilino-fumarates with lead tetra acetate/ trifluoroacetic acid give mixtures of oxazin, azobenzene and anilide.