A New Class of Easily Generated TCNQ2--Based Coordination Polymers

New types of coordination polymers containing [M(TCNQ)] sheets in which the TCNQ component is present as the little known dianion TCNQ(2-) are obtained in a very simple manner using readily available TCNQH(2) (i.e. 1,4-(NC)(2)CH center dot C6H4 center dot CH(CN)(2)) as the starting material. Above and below the metal centers in the sheets, a range of pyridine derivatives can be attached, some terminal and some acting as pillars linking sheet to sheet to form a 313 coordination network. The following compounds, generally in solvated form, were isolated and structurally characterized-[M(TCNQ)(pyridine)(2)] (M = Mn or Zn), [M(TCNQ)(quinoline)(2)] (M=Co or Zn), [Mn(TCNQ)(4-methylpyridine)(2)], [Zn(TCNQ)(4-phenylpyridine)(2)], [Zn(TCNQ)(isoquinoline)(2)], [Zn(TCNQ)(nicotinamide)(2)], [M(TCNQ)(bipy)] (M=Mn, Fe, Zn, Cd, and bipy = 4,4'-bipyridine, which links sheet to sheet to generate 3D coordination polymers), [Zn(TCNQ)(bpe)] (bpe = 1,2-bis(4-pyridyl)ethylene), and [Zn(CH3OH)(TCNQ)(Obip)(1/2)] (Obip = 4,4'-bipyrichne di-N-oxide). The TCNQH(2)/TCNQ(2-) approach opens the way to numerous new types of crystalline and structurally characterizable TCNQ-based networks (and not just the sheet structures that are the focus of this preliminary report) that may lead to solids with unusual and useful electronic/magnetic properties.