A catalytic composition comprising a complex of metal oxides wherein the relative ratios of the elements in said catalyst are represented by the following formula: Mo 12 Bi a Fe b A c D d E e F f G g Ce h O n wherein: A is at least one element selected from the group consisting of sodium, potassium, rubidium and cesium; and D is at least one element selected from the group consisting of nickel, cobalt, manganese, zinc, magnesium, calcium, strontium, cadmium and barium; E is at least one element selected from the group consisting of chromium, tungsten, boron, aluminum, gallium, indium, phosphorus, arsenic, antimony, vanadium and tellurium; F is at least one element selected from the group consisting of a rare earth element, titanium, zirconium, hafnium, niobium, tantalum, aluminum, gallium, indium, thallium, silicon, germanium, and lead; G is at least one element selected from the group consisting of silver, gold, ruthenium, rhodium, palladium, osmium, iridium, platinum and mercury; and a, b, c, d, e, f, g, h and n are, respectively, the atomic ratios of bismuth (Bi), iron (Fe), A, D, E, F, G, cerium (Ce) and oxygen, relative to 12 atoms of molybdenum (Mo), wherein a is from 0.05 to 7, b is from 0.1 to 7, c is from 0.01 to 5, d is from 0.1 to 12, e is from 0 to 5, f is from 0 to 5, g is from 0 to 0.2, h is from 0.01 to 5, and n is the number of oxygen atoms required to satisfy the valence requirements of the other component elements present; wherein 0.3 ≤ (a+h)/d ≤ 1 and 1.5 ≤ h/b ≤ 5, and wherein the X-ray diffraction pattern of the above identified catalytic composition has X-ray diffraction peaks at 2θ angle 28 ± 0.3 degrees and 2θ angle 26.5 ± 0.3 degrees, and wherein the ratio of the intensity of the most intense x-ray diffraction peak within 2θ angle 28 ± 0.3 degrees to the intensity of most intense x-ray diffraction peak within 2θ angle 26.5 ± 0.3 degrees is defined as X/Y, and wherein X/Y is greater than or equal to 0.8. A is at least one element selected from the group consisting of sodium, potassium, rubidium and cesium; and D is at least one element selected from the group consisting of nickel, cobalt, manganese, zinc, magnesium, calcium, strontium, cadmium and barium; E is at least one element selected from the group consisting of chromium, tungsten, boron, aluminum, gallium, indium, phosphorus, arsenic, antimony, vanadium and tellurium; F is at least one element selected from the group consisting of a rare earth element, titanium, zirconium, hafnium, niobium, tantalum, aluminum, gallium, indium, thallium, silicon, germanium, and lead; G is at least one element selected from the group consisting of silver, gold, ruthenium, rhodium, palladium, osmium, iridium, platinum and mercury; and a, b, c, d, e, f, g, h and n are, respectively, the atomic ratios of bismuth (Bi), iron (Fe), A, D, E, F, G, cerium (Ce) and oxygen, relative to 12 atoms of molybdenum (Mo), wherein a is from 0.05 to 7, b is from 0.1 to 7, c is from 0.01 to 5, d is from 0.1 to 12, e is from 0 to 5, f is from 0 to 5, g is from 0 to 0.2, h is from 0.01 to 5, and n is the number of oxygen atoms required to satisfy the valence requirements of the other component elements present; a is from 0.05 to 7, b is from 0.1 to 7, c is from 0.01 to 5, d is from 0.1 to 12, e is from 0 to 5, f is from 0 to 5, g is from 0 to 0.2, h is from 0.01 to 5, and n is the number of oxygen atoms required to satisfy the valence requirements of the other component elements present;