The reaction of trialkylaluminum compounds with diphenic acid in a 2:1 molar ratio results in the formation of novel dialkylaluminum dicarboxylates [Et(4)Al(2)(OOCC(12)H(8)COO)](3) (1) and [(i)Bu(4)Al(2)(OOCC(12)H(8)COO)](2) (2). Molecular structures of the compounds have been determined by X-ray crystallography. Compound 1 is a hexamer with a skeleton framework consisting of four fused heterocyclic rings, one 27-membered and three Al(2)O(4)C(2) 8-membered. Compound 2 is a centrosymmetric tetramer with a skeleton framework consisting of three fused heterocyclic rings, one 18-membered and two Al(2)O(4)C(2) 8-membered. The structures of the compounds reveal R(4)Al(2)O(4)C(2) subunits, each linked through diphenyl C(12)H(8) bridges. Each of the aluminum atoms is bonded to two alkyl groups and two oxygen atoms originating from two different dicarboxylate moieties.