Molecular and Multidimensional Organic−Inorganic Hybrids Based on Polyoxometalates and Copper Coordination Polymer with Mixed 4,4‘-Bipyridine and 2,2‘-Bipyridine Ligands

Three novel organic−inorganic hybrid materials with mixed 4,4‘-bipyridine and 2,2‘-bipyridine ligands, K[{Cu I (2,2‘-bipy)}(4,4‘-bipy){Cu I (2,2‘-bipy)} 0.5 ] 2 [Mo 8 O 26 ] ( 1 ), [Cu I (4,4‘-bipy)] 3 [PMo 10 VI Mo 2 V O 40 {Cu II (2,2‘-bipy)}] ( 2 ), and [Cu I (2,2‘-bipy)(4,4‘-bipy) 0.5 ] 2 [Cu I (4,4‘-bipy)] 2 [SiW 12 O 4 0 ] ( 3 ) (2,2‘-bipy = 2,2‘-bipyridine, 4,4‘-bipy = 4,4‘-bipyridine), have been hydrothermally synthesized. Compound 1 is a novel β-[Mo 8 O 26 ] 4- polyoxoanion bisupported by copper(I) coordination cations with mixed 4,4‘-bipy and 2,2‘-bipy ligands. Compound 2 consists of the divalent copper {Cu II (2,2‘-bipy)} 2+ capped [PMo 10 VI Mo 2 V O 40 ] 5- building blocks linked by {Cu(4,4‘-bipy)} n n + linear cationic chains into a novel two-dimensional (2D) network. To the best of our knowledge, compound 2 exhibits an unprecedented 2D structure containing the divalent copper capped polyoxometalate as building blocks. The novel structure of 3 is composed of one-dimensional hybrid zigzag chains linked by {Cu(4,4‘-bipy)} n n + chains into a three-dimensional (3D) framework via weak Cu−O interactions. The novelty of compound 3 is that it is the first time that a novel 3D framework has been formed by polyoxometalate and transition metal coordination polymer chains with mixed 4,4‘-bipy and 2,2‘-bipy.