Design of conducting redox polymers: A polythiophene‐Ru(bipy)₃;^n⊕Hybrid Material

Abstract

Many metal oxides and halides derive their conducting and magnetic properties from rapid self-exchange between metals in mixed oxidation states or from delocalized fractional valence states."] Hence, hybrid molecular systems derived from conjugated organic polymers which incorporate redox-active transition metal centers represent a promising approach to materials which display similar properties.Although there have been extensive investigations of polymers with redox-active metal there have been few examples of materials in which the metal-free organic portion is delocalized and electronically conductive.[41 The notion that a conductive polymer should be an efficient conduit for the electron transport makes intuitive sense. However, there is much to learn about how the degree of electronic communication between the redox centers and the polymer can influence the conductive and electrochemical properties of such materials. This understanding is certain to be useful for the development of materials for electr~catalytic,[~] sensory, and magnetic applications. Toward this end, we report herein the synthesis of a conducting p~lythiophene-Ru'@(bipy)~ hybrid material as well as the polymers derived from the non-metallated ligand. We find that this hybrid system exhibits high redox conductivity involving self-exchange between localized Run@ sites and thereby c o n h s the merits of this approach.Our choice of R~'@(bipy)~ centers as the redox component is the result of the broad manifold of reversible electrochemical activity displayed by this type of complex.[61 To achieve a maximum interaction between the polymer and the metal, the bipyridine ligands are incorporated directly into the polymer backbone. The thiophene residues were chosen to allow the polymer synthesis by electrochemical ~x i d a t i o n .~~] The first ligand investigated was 5,5'-bis(2"thiophene)-2,2'-bipyridine,

Ground and excited state communication within a ruthenium containing benzimidazole metallopolymer

“…4,5 In particular, benzimidazole polymers are attractive since metal complexes can be coordinated to the polymer backbone opening up the possibility of site-to-site electron hopping as well as electron transfer mediated by the polymer backbone 30 itself. 6,7,8,9,10,11,12 These conjugated metallopolymers are attracting increasing attention because of their potentially widespread applications, 13,14,15,16,17,18 and significant attention has been paid to polymers containing poly(pyridyl) complexes of 35 ruthenium(II) and osmium(II). 19,20,21,22 These metal complexes confer attractive redox and photophysical properties on the polymer and different metal loadings can be prepared by simply varying the relative mole ratio of the reactants.…”

Spectroelectrochemistry of alternating ambipolar copolymers of 4,4′- and 2,2′-bipyridine isomers and quaterthiophene

“…Of three different symmetric isomers of this double heterocyclic unit: 2,2'-bipyridine, 3,3'-bipyridine and 4,4'-bipyridine, the first has been by far the most intensively researched motif owing to its chelating properties, making it a handy substrate for developing elaborate organic ligand scaffolds. Many derivatives of 2,2'-bipyridine with thienyl [4][5][6][7][8][9][10][11], bithienyl [11][12][13][14][15][16], and oligothienyl [11] pendants at the 4,4'- [5][6][7]9,10,13,14] and 5,5'- [4,8,12,14,15] positions have been prepared and described in the literature as ligands in Ru [4][5][6][7][8][9][10]13], Zn, or Cu [16] complexes. All these organometallic structures were dedicated to organic electronics, examined primarily for dye-sensitized solar cells technology [5][6][7][8][9][10]13,15], while free ligands were investigated as polymerisable precursors for conducting polym...…”

Long‐Lived, Emissive Excited States in Direct and Amide‐Linked Thienyl‐Substituted RuII Complexes

“…A bithienyl analog of tL, btL was prepared by a modified Stille coupling. [37,38] Ligand sec-amL was prepared using a modified, previously reported procedure where thiophene-2-carboxylic acid chloride was treated with 4,4′-diamino-2,2′-bipyridine. [28] The sec-amL ligand was converted into the tert-amL analog via deprotonation of the amide by solid KOH in DMSO, followed by reaction with CH 3 CH 2 I.…”