title: Metal-carboxylate coordination polymers with redox-active moiety of tetrathiafulvalene (TTF).
abstract: Though numerous metal-organic frameworks or polymers have been reported, the organic building blocks are usually not redox-active. On the other hand, some mono-, di- or tri-nuclear compounds with tetrathiafulvalene (TTF) have been prepared, although little is known about the coordination polymers combined with paramagnetic metals and organic TTF ligands. We report herein a series of coordination polymers of copper(II) and manganese(II) with TTF dicarboxylate ligand (L). Compound 1, [CuL(2,2-bpy)](n), is a one-dimensional (1-D) coordination polymer with five-coordinated square-pyramidal Cu(II) centers. Mn(II) complex 2, [MnL(2,2-bpy)](n), also takes a 1-D structure, showing a double-bridged mode by carboxylate groups. The 4,4-bipyridine compound 3, [MnL(4,4-bpy)(H(2)O)](n)·CH(3)CN, takes a 2-D grid network. A zinc(II) compound 4, [ZnL(4,4-bpy)(H(2)O)](n)·CH(3)CN, isomorphous structure with 3, is also presented. The electrochemical properties of the solid-state compounds were investigated by cyclic voltammetry using surface-modified electrodes. As usually observed in TTF derivatives, two sets of redox-waves were observed. The values of E(1/2)(1) of compounds 1-4 are in the order of 2(Mn) ≈ 3(Mn) < 1(Cu) < 4(Zn), indicating that the metal coordination can affect the potential shift of the TTF ligand. Weak antiferromagnetic exchanges are observed for compounds 1, 2, and 3.
authors.affiliation: Department of Chemistry and Key Laboratory of Organic Synthesis of Jiangsu Province, Soochow University, Suzhou, 215123, People's Republic of China. zhuqinyu@suda.edu.cn
authors.forename: Qin-Yu
authors.initials: QY
authors.lastname: Zhu
authors.forename: Jin-Po
authors.initials: JP
authors.lastname: Wang
authors.forename: Yu-Rong
authors.initials: YR
authors.lastname: Qin
authors.forename: Zheng
authors.initials: Z
authors.lastname: Shi
authors.forename: Qiong-Hua
authors.initials: QH
authors.lastname: Han
authors.forename: Guo-Qing
authors.initials: GQ
authors.lastname: Bian
authors.forename: Jie
authors.initials: J
authors.lastname: Dai