A catalyst for, and method of, producing a reaction product predominantly of maleic anhydride, that is a product of reaction containing a ratio of maleic to citraconic anhydrides of at least 25 to 1, respectively, and preferably greater than about 100 to 1, respectively, by reacting a feed stream consisting of oxygen or an oxygen-containing gas and an organic C.sub.5 feed predominantly of piperylene and dicyclopentadiene, and preferably predominantly dicyclopentadiene, at bath temperatures of from about 360.degree. to about 450.degree. C. over a catalyst comprising a mixture of 25 to 60 weight percent titanium oxide (TiO.sub.2), 5 to 40 weight percent molybdenum oxide (MoO.sub.3) and 30 to 60 weight percent vanadium oxide (V.sub.2 O.sub.5) on an alpha alumina or alumina-silica carrier having less than about one square meter per gram (