Conducting polymers can be easily obtained by electrochemical oxidation of aromatic monomers on an electrode surface as a film state. To prepare conducting polymer fibres by electropolymerization, templates such as porous membranes are necessary in the conventional methods. Here we report the electropolymerization of 3,4-ethylenedioxythiophene and its derivatives by alternating current (AC)-bipolar electrolysis. Poly(3,4-ethylenedioxythiophene) (PEDOT) derivatives were found to propagate as a fibre form from the ends of Au wires used as bipolar electrodes (BPEs) parallel to an external electric field, without the use of templates. The effects of applied frequency and of the solvent on the morphology, growth rate and degree of branching of these PEDOT fibres were investigated. In addition, a chain-growth model for the formation of conductive material networks was also demonstrated.

The organic tailoring of internal surfaces of mesoporous silica [1±10] has recently received much attention owing to a range of potential applications in catalysis, [11,12] adsorption, and separation. [13] The covalent attachment of alkylsulfonic acid groups to silica surfaces by post-synthesis grafting or one-pot synthesis has been proposed for the fabrication of strong acid sites in mesoporous silica and periodic mesoporous organosilica (PMO).[14±24] Sulfonic groups have to date been obtained via the oxidation of propanethiol groups, [15±20,24] which results in a loss of mesoscopic ordering and degradation of textural properties. In addition, incomplete oxidation of the thiol groups [19,24] 3 , is hydrolyzed and condensed in acidic solution in the presence of a block copolymer surfactant to prepare the hybrid mesoporous ethenylene-silica (HME). The resulting material exhibits a hexagonally ordered mesoporous structure with p6mm symmetry, and the bridged ethenylene groups are homogeneously incorporated into the framework without Si±C bond cleavage. The pendant phenylene groups are introduced at the ethenylene sites on the surface by the Diels±Alder reaction with benzocyclobutene. The incorporated phenylene is anchored to the framework by two alkyl chains at the 1,2-substitution (Fig. 1C). Although the surface area decreases slightly from 652 to 506 m 2 g ±1 during this procedure, the original hexagonal mesoporous structure is completely preserved. The change in mesopore diameter from 6.8 to 6.0 nm while maintaining the original narrow pore size distribution is indicative of the homogeneous modification of ethenylene sites on the surface. The sulfonation of pendant phenylene groups can then be readily achieved by simple treatment in concentrated H 2 SO 4 . The original organic±inorganic network and mesoporous structure is retained, and the resulting material exhibits a uniform pore size of 6.0 nm, a relatively high surface area of 565 m 2 g ±1 , and a mesopore volume of 0.78 mL g ±1 . Therefore, it is reasonable to suppose that the evolution of phenylenesulfonic acid groups (Ph±SO 3 H) at ethenylene sites is achieved without degradation of the original mesoporosity and mesoscopic ordering (see Supporting Information). The change in organic groups in the framework was confirmed by NMR analysis.13 C cross-polarization magic-angle spinning (CP-MAS) NMR spectra of the original mesoporous ethenylene-silica (HME), Ph-HME, and Ph-SO 3 H HME are shown in Figure 2A. The spectrum of the original HME ( Fig. 2A(a)) clearly exhibits one intense signal at 146 ppm with spinning sidebands, which can be assigned to the siliconbridged ethenylene carbon. The absence of signals attributable to the block copolymer surfactant at around 70 ppm demonstrates successful removal of the template. After the Diels±Alder modification, three aromatic resonances at 126, 129, and 137 ppm appear in the spectrum, reflecting the three different kinds of carbons in the 1,2-substituted benzene. Additional peaks at 29 and 18 ppm are attributable to a...

Coordination polymerizations of para-substituted phenylallenes (2a−2e) were carried out by using [(π-allyl)NiOCOCF3]2 (1) as an initiator. The polymerizations were found to proceed through a living mechanism to yield polymers exclusively composed of 2,3-polymerized units in high yields, where the resulting polymers have predictable molecular weights and narrow molecular weight distributions. From kinetic studies, the polymerization rate was found to increase with the electron-donating character of the para substituent in 2. The coordination polymerizations of α-methylphenylallene (2f) and γ-methylphenylallene (2g) were also carried out to produce soluble polymers. In these cases, the methyl substituent on the allene moiety (especially at the γ-position) was found to reduce the polymerizability. A plausible polymerization mechanism was also discussed based on the results obtained in the study.

A coordination polymerization of alkoxyallenes (2a-2f) by the [q3-(allyl)NiOCOCF3] (1) /PPh, system was carried out to obtain a polymer (3) bearing exomethylenes on the main chain. The structure of the obtained polymer was confirmed by 'H-, "C-NMR and IR spectra, and was revealed to consist of two units, one bearing an exomethylene side chain and the other an end ether side chain as a result of 1,2-and 2,3-~olymerization. In the case of methoxyallene, the ratio was estimated as 32:68. The number average molecular weight (M&f t& resulting polymer varied linearly with increasing ratio of monomer to initiator. The molecular weight distributions (MJM,,) of the polymers obtained here were always approximately 1.1.These results may strongly support that the present polymerization proceeds bya living mechanism. Under an inert atmosphere, the propagating end of the polymer was quite stable and could be kept without any decrease in activity for more than a week. The proportion of 1,2-and 2,3-polymerization was a little affected by the substituents on the alkoxyallenes, as the steric bulkiness of the substituents increased the content of 2,3-polymerization units.

We report the first ever use of electrochemically mediated atom transfer radical polymerization (eATRP) employing a bipolar electrochemical method for the fabrication of both gradient and patterned polymer brushes. A potential gradient generated on a bipolar electrode allowed the formation of a concentration gradient of a Cu(I) polymerization catalyst through the one-electron reduction of Cu(II) , resulting in the gradient growth of poly(NIPAM) brushes from an initiator-modified substrate surface set close to a bipolar electrode. These polymer brushes could be fabricated in three-dimensional gradient shapes with control over thickness, steepness, and modified area by varying the electrolytic conditions. Moreover, by site-selective application of potential during bipolar electrolysis, a polymer brush with a circular pattern was successfully formed. Polymerization was achieved using both a polar monomer (NIPAM) and a nonpolar monomer (MMA) with the eATRP system.

A synthetic method to obtain an arsole-containing π-conjugated polymer by the post-transformation of the organotitanium polymer titanacyclopentadiene-2,5-diyl unit with an arsenic-containing building block is described. The UV/Vis absorption maximum and onset of the polymer were observed at 517 nm and 612 nm, respectively. The polymer exhibits orange photoluminescence with an emission maximum (E ) of 600 nm and the quantum yield (Φ) of 0.05. The polymer proved to exhibit a quasi-reversible redox behavior in its cyclic voltammetric (CV) analysis. The energy levels of the highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) were estimated to be -5.43 and -3.24 eV, respectively, from the onsets for oxidation and reduction signals in the CV analysis. Further chemical modification of the arsole unit in the π-conjugated polymer by complexation of gold(I) chloride occurred smoothly resulting in the bathochromic shift of the UV/Vis absorption and lowering of the LUMO energy level.

[reaction: see text] An unexpected tri-n-butylphosphine-catalyzed zipper cyclization of diyne[bond]diones (1a-d) or yne-diones (1e and 1f) is described. Bicyclic ketones (2a, 2b, 2c, 2e, and 2f) with five- or six-membered rings fused to the five-membered ring were obtained from both aliphatic diyne-diones (1a-c) and yne-diones (1e and 1f) having tetra- or pentamethylene spacers. The bicyclic products (2) were produced with high diastereoselectivity.

2,5-Diarylarsoles were easily synthesized from nonvolatile arsenic precursors. Diiodoarsine was generated in situ and reacted with titanacyclopentadienes to give 2,5-diarylarsoles. The structures and optical properties were studied in comparison with those of 2,5-diarylphosphole. It was found that the arsoles were much more stable in the air than the phosphole. Single crystal X-ray diffraction revealed the arsenic atoms adopted a trigonal pyramidal structure, reflecting on the s-character of the lone pair. The obtained 2,5-diarylarsoles and 2,5-diarylphosphole showed intense emission in solutions and solid state. In addition, the optical properties were controlled by transition-metal coordination.