Redox‐Active Coordination Polymers from Esterified Hexavanadate Units and Divalent Metal Cations

The redox‐active bis(pyridyl)‐capped hexavanadate [V 6 O 13 {(OCH 2 ) 3 C(4‐CONHC 5 H 4 N)} 2 ] 2– ( 1 ) reacts with divalent first‐row transition‐metal cations (Mn II , Co II , Ni II , or Zn II ) to yield crystalline linear zwitterionic coordination polymers ( 1 M). The zwitterionic coordination chains are connected to each other by hydrogen bonds to form a 3D network. Microporous channels are formed along the packing axes of the 2D networks. All four compounds exhibit almost identical cell parameters, space group ( P $\bar {1}$ ) and crystal morphology. The materials have been characterized by X‐ray crystallography, 1 H and 51 V NMR, IR, UV/Vis, elemental analysis, and TGA. All compounds 1 M are reversibly reduced by chemical reductants such as phenylhydrazine and NaBH 4 in CCl 4 in which the hexavanadates are insoluble. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)