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ABSTRACT New monomers containing 4-cyanophenyl (-PhCN) groups attached to a thieno[3,2- b]thiophene (TT) or dithieno[3,2- b:2′,3′- d]thiophene (DTT) structure were synthesized and characterized as 4-(2,5-dibromothieno[3,2- b]thiophen-3-yl)benzonitrile (Br-TT-PhCN) or 4,4′-(2,6-dibromodithieno[3,2- b:2′,3′- d]thiophene-3,5-diyl)dibenzonitrile (Br-DTT-PhCN). The Suzuki coupling of 9,9-dioctylfluorene-2,7-diboronic acid bis(1,3-propanediol)ester and the Br-TT-PhCN or Br-DTT-PhCN monomer was utilized for the syntheses of novel copolymers poly{9,9-dioctylfluorene-2,7-diyl- alt-3-(4′-cyanophenyl)thieno[3,2- b]thiophene-2,5-diyl} (PFTT-PhCN) and poly{9,9-dioctylfluorene-2,7-diyl- alt-3,5-bis(4′-cyanophenyl)dithieno[3,2- b:2′,3′- d]thiophene-2,6-diyl} (PFDTT-PhCN), respectively. The photophysical, electrochemical, and electroluminescent (EL) properties of these novel copolymers were studied. Their photoluminescence (PL) exhibited the same emission maximum for both copolymers in solution. Red-shifted PL emissions were observed in the thin films. The PL emission maximum of PFTT-PhCN was more significantly redshifted than that of PFDTT-PhCN, indicating more pronounced excimer or aggregate formation in PFTT-PhCN. The ionization potential (HOMO level) and electron affinity (LUMO level) values were 5.54 and 2.81 eV, respectively, for PFTT-PhCN and were 5.57 and 2.92 eV, respectively, for PFDTT-PhCN. Polymer light-emitting diodes (LEDs) with copolymer active layers were fabricated and studied. Anomalous behavior and memory effects were observed from the current-voltage characteristics of the LEDs for both copolymers. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017, 55, 2629-2638 [ABSTRACT FROM AUTHOR]

The synthesis of thioethers in excellent yields was achieved under mild conditions via the displacement reaction of halogens by sulfur. The cross-reaction of 2-(α-bromoacetyl)thiophene with triethylamine-activated phosphorus decasulfide (Et3N--P2S5) was elaborated by utilizing DFT calculations. [ABSTRACT FROM AUTHOR]

A simple and eco-friendly procedure has been devised for the green synthesis of palladium nanoparticles, using the aqueous extract of herbal tea ( Stachys lavandulifolia), a renewable and nontoxic natural phyto-exudate. The water-soluble components of the extract act as reducing agent and stabilizer. This green route does not require a surfactant or capping agent for the growth of palladium nanoparticles. The generated nanoparticles were analysed using UV-visible spectroscopy, transmission , X-ray diffraction, Fourier transform , scanning , energy dispersive X-ray analysis and . The palladium nanoparticles having spherical shape and dimensions of between 5 and 7 nm were employed as a homogeneous catalyst for Suzuki conducted in water under mild conditions. Good yields of products, a facile work-up, no evidence of leached palladium from the catalyst surface and smooth recovery of the by adding ethyl acetate, which could be reused at least eight times, confirm the very good efficiency of the catalytic reaction. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

A novel monomer, 2,6-di(thiophene-2-yl)-3,5bis(4-(thiophene-2-yl)phenyl)dithieno[3,2- b;2',3'- d]thiophene (Th4DTT) has been synthesized and used as an electro-active material. It has been electropolymerized onto glassy carbon (GC) electrode in sodium dodecyl sulfate (SDS) solution (0.1 M) together with multi-walled carbon nanotubes (MWCNT). A good capacitive characteristics for P(Th4DTT)/MWCNT composite has been obtained by electrochemical impedance spectroscopy (EIS), which is, to our best knowledge, the first report on capacitor behavior of a dithienothiophene. A synergistic effect has been resolved by Nyquist, Bode-magnitude-phase and admittance plots. Specific capacitance of the conducting polymer/MWCNT, calculated from cyclic voltammogram (CV) together with area and charge formulas, has been found to be 20.17 F g−1. Long-term stability of the capacitor has also been tested by CV, and the results indicated that, after 500 cycles, the specific capacitance is 87.37% of the initial capacitance. An equivalent circuit model of Rs( C1( R1( Q( R2 W))))( C2 R3) has been obtained to fit the experimental and theoretical data. The double layer capacitance ( Cdl) value of P(Th4DTT)/MWCNT (4.43 mF cm−2) has been found to be 25 times higher than P(Th4DTT) ( Cdl= 0.18 mF cm−2). © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40061. [ABSTRACT FROM AUTHOR]

Highlights: [•] First example of electrochromic devices of thieno[3,2-b]thiophenes. [•] They are particularly good at stability and open circuit memory. [•] The devices operate in the range of 0.0–1.6Vs, between pinkish orange and light blue grey colors. [ABSTRACT FROM AUTHOR]

Dithieno[2,3-b;3?,2?-d]thiophenes (DTT), having substituted phenyl groups at 3- and 4-carbons, have been synthesized, applying 2,5-diketone ring closure reaction using P4S10. Cyclic voltammetry studies indicated that all the DTTs had the oxidation potentials between 1.19 and 1.70 V. Computational calculations displayed positive radical spin densities at C2 positions for DTTs and negative for their dimers. [ABSTRACT FROM AUTHOR]