Abstract: A class of cation-reordered, bismuth-containing compounds having a perovskite-type structure of the formulaBa.sub.2 La.sub.y Bi.sub.2-y O.sub.6wherein y is greater than 0 but less than 1, is provided. Preferably, y is from 0.25 to 0.75, and most preferably y is 0.5.The compositions herein are found to be particularly advantageous in the selective production of aromatic compounds from acyclic olefins, particularly in the production of benzene from propylene.

Abstract: A class of oxygen-deficient, barium-containing compounds having a perovskite-type structure may be prepared which are of the formula:Ba.sub.2 M.sub.a M'.sub.2-a O.sub.5+yif M is a trivalent cation, orBa.sub.3 M.sub.a M'.sub.3-a O[7.5-(a/2)+y]if M is a divalent cation, wherein M is Mg, Ca, Sr, Ba, Sc, Y, La, the lanthanides of atomic number 58 or greater, Ni, Fe, Cu,Al, Ga, In, Zn, Cd, Hg, Bi, Tl or a mixture thereof, M' is Sb or Bi, a is equal to or greater than O but less than or equal to 1, and if M is trivalent, y is equal to or greater than 0 but less than 1, and if M is divalent, y is equal to or greater than O but less than (3+a)/2.Preferably, the compounds herein are of the formula:Ba.sub.2 M.sub.a M'.sub.2-a O.sub.5+ywhere M is La or Sc, a is equal to or greater than O but less than or equal to 1 and y is equal to or greater than O but less than 1.This class of compounds are readily reoxidized and therefore are useful in oxidative dehydrogenation reactions.