A series of bis(2-(3,4-ethylenedioxy)thiophene)-based monomers have been synthesized and fully characterized; specifically (E)-1,2-bis(2-(3,4-ethylenedioxy)thienyl)vinylene (BEDOT-V), 1,4-bis(2-(3,4-ethylenedioxy)thienyl)benzene (BEDOT-B), 4,4‘-bis(2-(3,4-ethylenedioxy)thienyl)biphenyl (BEDOT-BP), 2,5-bis(2-(3,4-ethylenedioxy)thienyl)furan (BEDOT-F), 2,5-bis(2-(3,4-ethylenedioxy)thienyl)-thiophene (BEDOT-T), and 2,2‘:5‘,2‘‘-ter(3,4-ethylenedioxy)thiophene, TER-EDOT. The X-ray crystal structures of BEDOT-V and BEDOT-B have been determined. These monomers oxidize and polymerize at low potentials relative to other reported electropolymerizable heterocycles. The electroactive polymers formed exhibit low redox switching potentials and are quite stable in the conducting state. TER-EDOT was found to have the lowest peak oxidation potential of +0.2 V vs Ag/Ag+, making it the most easily oxidized polymerizable thiophene monomer reported. The electronic bandgaps of these EDOT based polymers range from 1.4 to 2.3 eV (measured as the onset of the π−π* transition) offering a diverse range of colors which may prove useful in electrochromic devices. For example, poly(BEDOT-V) is deep purple and opaque in the reduced state and transmissive sky blue in the oxidized state, poly(BEDOT-T) is deep blue opaque in the reduced state and transmissive blue in the oxidized state, while poly(BEDOT-BP) is transmissive orange in the reduced state and opaque purple in the oxidized state. A thin film of poly(BEDOT-V) was found to switch rapidly between redox states (under 2 s) with an initial optical contrast of 43%. This polymer was found to retain 47% of its optical contrast and 48% of its original charge density after 600 double potential steps.

Metallosupramolecular chemistry involves the use of combinations of organic ligands and metals for the construction of both discrete and polymeric aggregates. This Account describes some lessons that we have learned about aspects of ligand design in the course of our work in this area. Specifically, we recommend the incorporation of a diverse range of heterocyclic rings and arene cores within the ligands, as well as attention to symmetry considerations, and offer suggestions for the introduction of chirality and flexibility within the ligands and the exploitation of other weak interactions to assist self-assembly processes.

The low potential, redox‐active, highly stable conducting polymer PEDOT (poly(3,4‐ethylenedioxythiophene)) has received much attention recently because of these properties, which are likely to lead to many applications. Here the synthesis of EDOT‐TMS2 is reported (where TMS stands for trimethylsilyl and Bi indicates bis), together with the investigation of the electrochemical polymerization of these monomers using voltammetry and the electrochemical quartz crystal microbalance. The optical switching rates of the films on indium tin oxide are compared, showing that derivatization with TMS leads to improved characteristics.

We report the synthesis and electrochemical polymerization of a series of bisheterocycle-N-substituted carbazoles. These monomers exhibit low peak oxidation potentials (E p,m ) which range from 0.15 to 0.46 V vs Ag/Ag + , indicating facile polymerization. Repeated scan electrochemical polymerization for these monomers proceeds rapidly, relative to carbazole, to form stable electroactive films. Cyclic voltammetry of the polymers indicates that the films are well adhered to the electrode surface and that each of the polymers possess two distinct redox waves. At applied potentials greater than 1.15 V, a third irreversible oxidative process is observed, presumedly due to cross-linking. Optoelectrochemical analysis indicates that these polymers have an electronic bandgap (measured as the onset of the π-to-π* transition) between 2.4 and 2.5 eV. Three distinct colors are achievable by varying the redox state of the polymers suggesting potential use for multiply colored electrochromic displays. For the series of bis(ethylenedioxythiophene)-N-substituted carbazoles, the fully reduced form of the polymers are canary yellow. Upon mild oxidation, the films become green and in the fully oxidized form, blue.

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A family of six donor-acceptor-donor monomers was synthesized using combinations of thiophene, 3,4-ethylenedioxythiophene and 3,4-ethylenedioxypyrrole as donor moieties, and cyanovinylene as the acceptor moiety, to understand the effects of modified donor ability on the optoelectronic and redox properties of the resulting electropolymerized materials. Spectroelectrochemistry, differential pulse voltammetry, and cyclic voltammetry results indicate band gaps ranging from 1.1 to 1.6 eV and suggest that these polymers can be both p-type and n-type doped at accessible potentials. In situ conductivity results indicate that the n-type conductivity magnitude is modest, and the conductivity profile indicates a redox conductivity mechanism as opposed to a delocalized electronic band mechanism as observed for p-type doping.

Incarcerated in a helical prison: The encapsulation of a PF ion within a quadruply stranded helicate (shown schematically) results from the self-assembly of four molecules of 1,4-bis(3-pyridyloxy)benzene and two Pd ions. This represents not only the first example of a coordinatively saturated quadruple helicate, but also the first example of the encapsulation of a complex anion by a helicate.