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Synthesis of 3-(4-fluorophenyl)thieno[3,2-b]thiophene (FPhTT) and 3,3'-(4- fluorophenyl)dithieno[3,2-b;2',3'-d]thiophene (FPhDTT) were achieved starting from 3-bromothiophene and 3,4-dibromothiophene, respectively. They were electropolymerized and the resulting polymers P[FPhTT] and P[FPhTT] were characterized by diverse electrochemical methods such as cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), galvanostatic charge-discharge (GCD), electrochemical quartz crystal microbalance (EQCM) and spectroelectrochemical measurements. Mechanism of electropolymerization of the monomers was supported by DFT level calculations. Band gaps of P[FPhTT] and P[FPhTT] were calculated as 1.63 and 1.77 eV, respectively, from the onset absorptions of the absorption spectra. From EIS measurements, the highest capacitance values of P[FPhTT] and P[FPhTT]were calculated to be 39.4 and 281.7 Fg(1-), respectively, when the applied potentials were equal to their oxidation peak potentials. Surface characterization of the P[FPhTT] and P[FPhTT] films on ITO electrodes were performed by atomic force microscope (AFM) and the results suggested that P[FPhTT] had more porous surface. GCD results indicated that P[FPhTT] had higher energy density than P[FPhTT], possibly due to its porous structure. According to the ECD results, P[FPhTT] has more stable optical properties. As a conclusion, P[FPhTT] might be suggested for energy storage applications while P[FPhTT] could be suitable for electrochromic devices. (C) 2021 Elsevier Ltd. All rights reserved.

A wide series of 10 new triphenylamine (TPA)/4,4'-dimethoxytriphenylamine (TPA(OMe)(2))-functionalized thieno[3,2b]thiophene (TT) fluorophores, 4a-e and 5a-e, bearing different electron-donating and electron-withdrawing substituents (-PhCN, -PhF, -PhOMe, -Ph, and -C6H13) at the terminal thienothiophene units were designed and synthesized by the Suzuki coupling reaction. Their optical and electrochemical properties were investigated by experimental and computational studies. Solid-state fluorescent quantum yields were recorded to be from 20 to 69%, and the maximum solution-state quantum efficiency reached 97%. Moreover, the photophysical characterization of the novel chromophores demonstrated a significant Stokes shift, reaching 179 nm with a bathochromic shift. They exhibited tuning color emission from orange to dark blue in solution and showed fluorescence lifetime reaching 4.70 ns. The relationship between triphenylamine (TPA)/4,4'-dimethoxytriphenylamine (TPA(OMe)(2))-derived triarylamines and different functional groups on thieno[3,2-b] thiophene units was discussed.

Three new pi-conjugated 4-(thieno[3,2-b]thiophen-3-yl)benzonitrile based monomers having thiophene, 3-hexylthiophene and EDOT at the peripherals were synthesized. Their electropolymerization produced the corresponding electroactive polymers, P1, P2, and P3, which exhibited electrochromic properties with color developments from red to blue, orange-yellow to pale-blue, and purple to pale-grey, respectively. Functional design of the monomers with electron deficient benzonitrile at ss-position of thieno[3,2-b]thiophene (TT) and electron-rich thienyl groups at the peripherals influenced the HOMO and LUMO levels and, thereby, reduced the band gap of the conjugated polymers. Considering the band gaps of electropolymerized TT based polymers in the literature, the polymer P3, obtained through electropolymerization, had a comparable band gap of 1.73 eV. Electrochromic devices (ECD) of the new polymers displayed different optical contrasts (Delta T%) of 20% at 507 nm, 25% at 443 nm, and 34% at 579 nm for P1/PProDOP, P2/PProDOP, and P3/PProDOP, respectively. Furthermore, they had modest switch times of 1.2-1.7 s for bleaching and 0.9-1.7 s for coloring. Of the polymers, P3/ PProDOP, bearing EDOT moieties, had a reasonable coloration efficiency (CE) of 240 cm2/C at 579 nm, excellent permanent memory effect, and high stability of color switch, retaining 88% of its electroactivity after 500 cycles, switching at the applied voltages of -0.2 and + 1.1 V.

In this study, we report a novel strategy to fabricate electro-responsive polybenzoxazine based high performance thermoset surfaces. Three structurally different benzoxazines form simple chemicals such as hydmquinone, formaldehyde, and corresponding primary amines were prepared and coated as thin films by solvent casting on ITO electrodes. Subsequently, they were cured by thermally activated ring opening polymerization. The structural characteristics and thermal behavior of the benzoxazines were evaluated by FTIR, H-1 NMR and DSC, respectively. The electrochemical properties of the films were investigated by using cyclic voltammetry. Finally, the surface properties of the films after redox processes were examined by contact angle measurements, scanning electron microscopy (SEM) and atomic force microscopy (AFM). This work presents a straightforward electrochemical method for tuning surface morphology and hydmphilicity by redox process through hydrogen bonding interactions.

Two novel copolymers of 4-thieno[3,2-b]thiophen-3-ylbenzonitrile (TT-CN), possessing electron withdrawing cyano moiety, with anthracene (P1) and biphenyl (P2) were prepared via Suzuki coupling. Optic, electronic, and thermal properties of the copolymers were investigated through UV-Vis spectroscopy, cyclic voltammetry, gel permeation chromatography, and thermal gravimetric analysis. The polymers with anthracene and biphenyl had electronic band gaps of 2.01 and 1.90 eV, respectively. Both polymers demonstrated excellent large Stokes shifts of 101 (anthracene) and 105 nm (biphenyl) as well as very good thermal properties. As they had good optical, electronic, and thermal properties, they are promising candidates for electronic applications.

Two novel selenophenothiophene homopolymers, P(SeT1) and P(SeT2), were electrochemically prepared for the first time from their corresponding monomers (i) conjugated 2,5-di(thiophen-2-yl)selenopheno[3,2-b]thiophene (1) and (ii) cross-conjugated 2,5-di(thiophen-2-yl)selenopheno[2,3-b]thiophene (2) to explore their electrochromic behaviors. The effects of conjugation and cross conjugation on the electrochromic performances and electrochemistry and spectroelectrochemistry of the polymers were systematically studied. While the cross conjugated polymer film of P(SeT2) displayed a color change from yellow to a light green upon oxidation, the conjugated polymer film of P(SeT1) showed an orange color in the neutral and a claret red in the oxidized state. The polymer P(SeT1), owing to its extended pi-conjugation, had a lower optical band gap of 1.82 eV, compared to the polymer P(SeT2) (2.27 eV). Their electrochromic performances displayed that P(SeT2) had a higher optical contrast (46.2%) and a lower response time (oxidation time of 1.34 s at 680 nm). The first electrochemicallysynthesized poly(selenophenothiophene) films showed good electrochemical activity and electrochromic properties. Moreover, this pioneering study suggests a new strategy for designing and preparing organic electrochromic materials possessing selenophenothiophene units.

Two dithieno[3,2-b;2 ',3 '-d]thiophenes, posessing donor-pi-acceptor (D-pi-A) character through electron donor triphenylamine and electron acceptor boron, were successfully synthesized. They had large Stokes shifts of 140 and 155 nm and exhibited remarkable solvatochromic behaviors. Emission colors changed from blue to orange in non-polar to polar solvents, respectively. They acted as colorimetric and fluorescent chemosensors with high sensitivity towards fuoride anion, displaying a blue shift from yellow upon addition of TBAF as a result of blocking D-A conjugation.

In this study, electropolymerization of pre-synthesized N,N '-di-[3-[2-(3-thienyl)ethyl] phenyl] perylene-3,4,9,10-bis(dicarboximide) (ThPDITh) was performed on Au button electrode and the properties of the resultant polymer P(ThPDITh) were investigated by electrochemical techniques. Effect of the polymerization charge on the redox behaviors of the polymer film was investigated by cyclic voltammetry (CV) and the polymer film was further characterized by electrochemical impedance spectroscopy (EIS) measurements. Corresponding electrical equivalent circuit was applied to the experimental data to explain the electrochemical phenomenon on the interface of the Au/P(ThPDITh). In order to obtain information on the energy storage properties of P(ThPDITh) as a pseudo-capacitive electrode material, important cell characteristics, such as redox process in anodic and cathodic potential ranges, stability of galvanostatic charge-discharge (GCD) curves, coulombic efficiency, capacitance, energy and power density values were determined. Capacitance values, obtained through different measurements (CV, EIS and GCD) are all in good agreement with each other. All the results suggested that P(ThPDITh) is capable of undergoing multiple reversible redox processes, and a good candidate for improving the capacitance and energy density of electrode material while still offering high power capability.

Thieno[3,2-b]thiophene (TT) and dithieno[3,2-b;3,2-d]thiophene (DTT) have drawn immense attention in the field of electronics and optoelectronics. In this work, the first examples of TTs (TPE2-TTandTPE3-TT) and a DTT (TPE2-DTT), having tetraphenylethylene (TPE) at the periphery exhibiting aggregation induced emission (AIE) in OLEDs, were designed and synthesized by the Suzuki coupling reaction. Their properties were investigated through experimental and computational studies, as well as X-ray diffraction and DFT optimization.TPE2-TTshowed excellent device performance with a maximum luminance of 11 620 cd m(-2), a maximum current efficiency of 6.17 cd A(-1)and a maximum external quantum efficiency of 2.43%. Moreover, these synthetically easily accessible molecules have high thermal stability, which makes them perfectly suitable for optical applications.

We have devised a novel and fluorescent chemodosimeter (ANT-Fe), possessing an anthracene scaffold as a fluorophore and ferrocene as a redox active unit for selective and sensitive detection of Cu2+ ions in aqueous media. Its synthesis was realized by a simple combination of two commercially available compounds, 2-aminoanthracene and ferrocenecarboxaldehyde, in one-step without required column chromatography for the purification process. The probe offers distinct properties such as aggregation induced emission, dual sensing mode of fluorometric "turn-off" and electrochemical signaling with cathodic shift, high selectivity towards Cu2+ ions, fast response time and low detection limit (2.5 ppb) via C=N bond hydrolysis. Detection of Cu2+ ions by ANT-Fe adsorbed on a test paper system with the naked eye as a practical application is also successfully reported.

We herein report photoinduced step-growth polymerization of highly conjugated 2,5-dithiophenyl (thieno[3,4-b] thiophene) (TTs) derivatives possessing 4-cyanophenyl or 4-methoxyphenyl or 3-(4-fluorophenyl) groups substituted at the terminal position. Upon irradiation at 350 nm, the excited state of these molecules forms exciplex with diphenyliodonium hexafluorophosphate (DPI) that undergoes electron transfer reaction forming radical cations. Successive proton release and radical coupling reactions yield corresponding oligothienothiophenes with overall yields varying between 19-74%. Structural and molecular weight characteristics of the oligomers thus formed were investigated by Ultraviolet, fluorescence, NMR (Nuclear Magnetic Resonance) and infrared (IR) spectroscopic methods, and GPC (Gel Permeation Chromatography), respectively. The effect of substitution and dithiophene side groups on the reactivity of the monomer and band gap of the oligomers formed was evaluated by using cyclic voltammetry.

Conjugated polymers are promising cost-effective, lightweight, and flexible electrode materials. 3,5-Dinonyl-2,6-di(thiophene-2-yl)dithieno[3,2-b : 2 ',3 ' d]thiophene (M1) as a donor and 4,4 '-dinonyl-5,5 '-di(thiophen-2-yl)-2,2 '-bithiazole (M2) as an acceptor were synthesized and their polymers poly(3,5-dinonyl-2,6-di(thiophene-2-yl)dithieno[3,2 b : 2 ',3 '-d]thiophene) (P1) and poly(4,4 '-dinonyl-5,5 '-di(thiophen-2-yl)-2,2 '-bithiazole) (P2) were obtained via electropolymerization on ITO/glass electrode surface in ACN : DCM (1 : 3 v/v) solution, containing 0.1 M tetrabutylammonium hexafluorophosphate (TBAPF(6)). Then, a third polymer as a co-polymer (P3) was synthesized through electropolymerization of a mixture of the monomers M1 and M2 in 1 : 1 ratio. All the polymers were characterized by UV-Vis, CV and CV-UV measurements. Moreover, capacitor properties of the polymers by potentiostatic electrochemical impedance spectroscopy (EIS) was performed. The polymers P1, P2 and P3 exhibited absorptions at 456, 453 and 519 nm in neutral state and their optical band gaps were determined to be 2.17, 2.53 and 1.95 eV, respectivetly. EIS measurements indicated that P3 had the highest current density, having lower resistance.

N-(4-(4-thieno [3,2-b]thiophen-3-yl-phenyl)phenye-N-phenylbenzenamine (TTpTPA), synthesized by Suzuki cross-coupling reaction, was electropolymerized in DCM/CAN (4/1 v/v) mixture, containing 0.1 M Bu4NPF6. Charge storage property of the polymer, investigated by electrochemical impedance spectroscopy measurements at different potentials, suggested that the highest capacitance value could be obtained at its anodic peak potentials. Double layer and low-frequency capacitances were found to be C-DL = 369 Fg(-1) and C LF = 447 Fg(-1) at E-DC = 1.23 V. These values are in good agreement with the results obtained from equivalent circuit model. Electrochromic properties of the corresponding polymer, PolyTTpTPA, were investigated by spectroelectrochemical measurements, which indicated that while the polymer had a gold-orange color in its neutral state with an absorption maximum of 378 nm, it became blue in its oxidized state with an absorption maximum of 850 nm. Chronocoulometric measurement of the film exhibited a residence time of 10 s, indicating a fast response time and stable photoelectrochemical behavior, which are the most important parameters for electrochromic applications. In addition, hydrophobic property of the film, having a contact angle measurement of 115 degrees, is a good advantage for electronic applications for outdoor and wet areas. This work demonstrates that reversible capacitive current property and porous structure of PolyTTpTPA, supported by SEM and AFM images, make it a good candidate for electrochromic and capacitor devices.

A novel sulfonic-functionalized ionic liquid, C3N4 (C3N4-SO3H (IL)), was prepared and its structure was characterized using FTIR, TEM. XRD, CH NS elemental analysis and FESEM-EDX mapping. Catalytic activity of the liquid was studied for the syntheses of pyrazolo[3,4-b]pyridine and bis(indolyl)methane derivatives under moderate conditions. The catalyst was demonstrated to be reused at least 5 runs without considerable decrease in its activity. Some of the important advantages of the methodology were proved to be good yields, easy work-up, short reaction time and broad scope of substrates. (C) 2020 Elsevier B.V. All rights reserved.

Applying thienothiophenes (TT) as a linker, a bulky bifunctional thienothiophene, TT-TPA-TPE3, possessing triphenylamine (TPA) and tetraphenylethylene (TPE) units, was designed, synthesized, and fully characterized. Its optical and electronic properties were explained by UV-Vis spectroscopy, cyclic voltammetry (CV) and Aggregation-Induced Emission (AIE) study. TT-TPA-TPE3 exhibited positive solvatochromism in the range of solvent polarities from DMF to toluene, displaying emissions from yellowish to bluish between 480-525 nm. Utilizing TT-TPA-TPE3 as a hole-transporting layer, its organic light emitting devices (OLEDs) were fabricated and their performances were investigated. The synthesized emitter exhibited green and blue emissions in device applications. A mega Stoke's shift of 114 nm in THF and a large Stoke's shift of 78 nm on ITO were observed. A maximum luminance of 580 cd m(-2) and a turn-on voltage of 7.01 V were obtained, indicating that TT-TPA-TPE3 has a good hole-transporting ability.

Four step synthesis of 3-alkylthieno[3,2-b]thiophenes in the literature was reduced to two steps in good yields, through the preparation of the mono ketone, i.e. 1-(thiophene-3-ylthio)alkan-2-one, from 3-bromothiophene and ring formation reaction. This convenient method provides an easy access with good yields to the preparation of 3-alkylthieno[3,2-b]thiophenes, which are important materials for organic electronic and optoelectronic applications. SEM, AFM and contact angle (CA) analyses of their electropolymers on indium tin oxide (ITO) indicated that as the alkyl chains became longer, the polymers provide a more hydrophobic layer with CA up to 107 degrees.

Synthesis of novel thieno[2,3-b]thiophenes (TTs) possessing para substituted phenyl groups (Ph-, MeOPh-, BrPh-, NO2Ph-, NH2Ph- and NMe2Ph-) at C-3 has been achieved through ring closure reactions of mono ketones, i.e. 1-aryl-2-(thiophen-2-ylthio)ethan-l-one, and polymerizations of TTs (PhTT (10), p-MeOPhTT (11), pNO(2) PhTT (13) and p-NMe2PhTT (18)) under Suzuki coupling condition are demonstrated. The optical and electronic properties of the polymers were investigated systematically. Polymers demonstrated bathochromic shift with respect to their monomers in UV-Vis investigations up to 203 nm for 23 consisting of NO2 unit. While unsubstituted phenyl possessing polymer has the smallest band gap of 2.18 eV, the largest one was noticed to be 2.65 eV for NMe2 containing polymer 24. Electrochemical studies revealed the relatively low oxidation potentials recorded between 1.10 and 1.31 V.

Two novel organoboron compounds BBTT1 and BBTT2 possessing conjugated thieno[3,2-b] thiophene and cross-conjugated thieno[2,3-b] thiophene, respectively, as electron donors (D) and bis-triarylboron units as electron acceptors (A) linked through thiophene pi spacers have been synthesized and structurally characterized by various spectroscopic methods. The donor capabilities of the thienothiophenes were examined in view of their electrochemical and photophysical properties. Also, their solvatochromic behaviour in different solvents as well as their anion-recognition ability have been thoroughly investigated. Compounds BBTT1 and BBTT2 act as colorimetric and fluorescent chemosensors with high sensitivity and selectivity towards F-. Furthermore, BBTT1 displays a peculiar redshift in fluorescent titration experiments upon the binding of F-to the borane moiety, and "turned-on" chemosensor character for the detection of fluoride, as illustrated by the accompanying change in emission colour. On the other hand, the binding of F-to BBTT2 reveals a "turned-off" sensor property. The electronic and structural characteristics of the two compounds and their fluoride-sensing properties were assessed by means of DFT computations.

Conjugated donor-acceptor (D-A) copolymers possessing alternating fused bicyclic aromatic rings thieno [3,2-b]thiophene, selenopheno[3,2-b]thiophene, thieno[2,3-b]thiophene and selenopheno[2,3-b]thiophene as donors, thiophene as a pi-conjugated bridge and mesitylboron as an acceptor were synthesized and characterized by spectroscopic methods. Large Stokes shifts of 96-166 nm were recorded and the solution quantum yields of the polymers were in the range of 5-18%. Their ionization potentials and electron affinities were investigated by cyclic voltammetry. Optical band gaps varied between 2.26 and 2.78 eV. (TD)-DFT studies were performed to unveil their electronic structures, Kohn-Sham orbitals and electronic transitions. Absorption and emission measurements revealed that these polymers have high sensitivity to fluoride anions, among which the polymer possessing cross-conjugated thienothiophene units had the best sensing properties supported by orbital composition analysis with Mulliken partition. Thus, copolymers P1-P4 could be used as colorimetric and fluorescent sensors for small fluoride anions.

Introduction - Salvia, an important and widely available member of Lamiaceae family. Although comparative analysis on secondary metabolites in several Salvia species from Turkey has been reported, their hallucinogenic chemicals have not been screened thoroughly.

Electrochemical properties of eugenol were investigated on a graphene modified carbon paste electrode (CPE) by using voltammetric methods, which exhibited a well-defined irreversible peak at about 0.7 V vs Ag/AgCl, NaCl (3 M) in Britton -Robinson buffer at pH 2.0. Mechanism of the electrochemical reaction of eugenol was studied by performing density functional theory (DFT) computations and mass spectroscopic analysis. (CPCM:water)-wB97XD/aug-cc-PVTZ//(CPCM:water)-wB97XD/6-31G(d) level calculations predicted that the formation of product P2, possessing a para-quinoid structure, is preferred rather than the product P1, suggested in the literature, having an ortho-quinoid system. Determination of eugenol in a pharmaceutical sample was realized in the light of the electrochemical findings, and a validated voltammetric method for quantitative analysis of eugenol in a pharmaceutical formulation was proposed. The differential pulse voltammogram (DPV) peak currents were found to be linear in the concentration range of 1.0 x 10(-7) to 1.7 x 10(-8) M. The limit of detection (LOD) and the limit of quantification (LOQ) were obtained to be 7.0 x 10(-9) and 2.3 x 10(-8), respectively.

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] thiophene3,5-diyl) dibenzonitrile (Br-DTT-PhCN). The Suzuki coupling of 9,9dioctylfluorene-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-diylalt-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. (C) 2017 Wiley Periodicals, Inc.

An electron rich conjugated microporous polymer (CMP) was prepared after reacting a dithienothiophene (DTT) derivative and benzene as co-monomers by Suzuki-Miyaura poly-condensation. Gas sorption measurements revealed a Brunauer-Emmett-Teller(BET) surface area of 421 m(2)g(-1) for the network. Its chemical oxidation was performed via iodine exposure, which is fully reversible with ammonia treatment resulting in a complete removal of the oxidants. This was observed in a decrease and recovery of the initial porosity due to reversible introduction and removal of iodide within the micropores, which could also be monitored by IR and UV/Vis absorption spectroscopy during the RedOx process.

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-(alpha-bromoacetyl) thiophene with triethylamine-activated phosphorus decasulfide (Et3N-P2S5) was elaborated by utilizing DFT calculations.

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Four groups of novel sulfonamide derivatives: (i) acetoxybenzamide, (ii) triacetoxybenzamide, (iii) hydroxybenzamide and (iv) trihydroxybenzamide, all having thiazole, pyrimidine, pyridine, isoxazole and thiadiazole moieties were prepared and their inhibitory effects were studied on two metalloenzymes, i.e. carbonic anhydrase isozymes (hCA I and II), purified from human erythrocyte cells by Sepharose-4B-l-tyrosine-sulfanilamide affinity chromatography. These enzymes are present in almost all living organisms to catalyse the synthesis of bicarbonate ion (HCO3-) from carbon dioxide and water. The sulfonamide derivatives were found to be active against hCA I and II in the range of 2.62-136.54 and 5.74-210.58nM, respectively.

In this work, donor acceptor (D - A) copolymers of thienothiophenes and dithienothiophenes, having 1,2,3-triazole units were prepared via a click reaction. Their optoelectronic properties were explored systematically providing the optical and electrochemical band gaps varying from 2.2 to 2.8 eV. Density functional theory (DFT) investigations of the model compounds revealed the presence of an intramolecular charge transfer transition between the donor TT/DTT units and 1,2,3-triazole acceptor group.

Dithienothiophene (DTT) based conjugated microporous polymers (CMPs) were synthesized by bulk and electrochemical oxidative polymerizations. Spectroelectrochemical measurements showed that DTT-CMP can be reversibly oxidized and reduced, accompanied by a significant change of the absorption properties making the material interesting for electrochromic devices. Reversible doping and dedoping of the bulk polymer network was also observed using iodine and ammonia, respectively. Nitrogen gas sorption measurements of the neutral, doped, and dedoped polymer networks indicated the presence of iodide species within the pores, and the conductivity of the networks is highly increased upon doping with iodine. The introduction of the strong electron donor DTT into a conjugated porous network, and the ability for redox switching, make DTT-CMPs interesting materials for organo(opto)electronic devices and sensors.

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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 electron microscopy, X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, energy dispersive X-ray analysis and inductively coupled plasma. The palladium nanoparticles having spherical shape and dimensions of between 5 and 7nm were employed as a homogeneous catalyst for Suzuki coupling reactions 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 catalysis by adding ethyl acetate, which could be reused at least eight times, confirm the very good efficiency of the catalytic reaction. Copyright (c) 2014 John Wiley & Sons, Ltd.

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-magnitudephase 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 R-s(C-1(R-1(Q(R2W))))(C2R3) has been obtained to fit the experimental and theoretical data. The double layer capacitance (C-dl) value of P(Th4DTT)/MWCNT (4.43 mF cm(-2)) has been found to be 25 times higher than P(Th4DTT) (C-dl= 0.18 mF cm(-2)). (c) 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40061.

3-Phenylthieno[3,2-b]thiophene, 3-(4-methoxyphenyl)thieno[3,2-b]thiophene and 3-(4-N,N-dimethylaminophenyl)thieno[3,2-b]thiophene were electropolymerized on ITO by applying constant potentials of 1.7, 1.65, and 1.4V, which had light transparent reddish yellow, brown and brownish yellow colors, respectively. Their electrochromic devices (ECD) were fabricated with PEDOT on ITO coated glass electrodes. Spectroelectrochemical and electrochromic properties of the devices were investigated in detail. A potential range of 0.0-1.6V was found to be suitable for operating the devices between pinkish orange and transparent light blue colors. The maximum transmittance difference (%Delta T) of the ECDs were measured to be 4.5, 7 and 3% and the time required to reach 95% of transmittance difference were 2, 1.85, and 1.8 s. They demonstrated good optical memory both in oxidized (with only transmittance changes of 1.5, I, and 2.5%) and reduced states (with almost no transmittance change). (C) 2013 Elsevier B.V. All rights reserved.

Three groups of fluorene-dithieno[3,2-b;2',3'-d]-thiophene-S,S-dioxides (DTT-S,S-dioxide) copolymers, each having four different ratios of DTT-S,S-dioxide (5, 15, 25, and 50%) were successfully synthesized through Suzuki coupling method. While the first group copolymers PI had direct connection of fluorene to the peripheral thiophenes of DTT-S,S-dioxide, second group copolymers P2 had a thiophene extension between fluorene and DTT-S,S-dioxide, and in the third group, copolymers P3, fluorene had a connection with DTT-S,S-dioxide through the phenyl moiety of DTT. Absorbance and emission measurements of first two groups P1 and P2 displayed a regular bathochromic shift with increasing content of DTT-S,S-dioxide, which was more clearly observed in their solid state fluorescence measurements. Introduction of thiophene to the peripherals of the DTT-S,S-dioxide in copolymers P2 caused even further bathochromic shift in absorbances and emissions. As the absorbance and emission of PI went up to 447 and 558 nm in solution, respectively, P2 had them at 472 and 592 nm, respectively. In solid state, emissions of 131 and P2 even went further up to 585 and 646 nm, respectively. The bathochromic trend of 131 and P2 became opposite with absorbance and solid state emission of P3, which had a hypsochromic shift with increasing content of DTT-S,S-dioxide. Solid state emission of P3, particularly the copolymers having 5, 15 and 50% DTT-S,S-dioxide, covered a wide region between 400 and 675 nm. A spread of colors from light blue (border of white) to red through green and yellow was obtained with the OLED applications of the copolymers. Their optical and electronic band gaps varied between 2.17 and 2.99 eV and between 2.68 and 3.57 eV, respectively. While the highest quantum yield was obtained with P2 (5%) as 0.66, the lowest was observed with P2 (50%) as 0.03. Almost all of the polymers displayed good thermal stabilities. No weight loss was observed with the copolymers P2 (5-15%) and P3 up to 400 degrees C.

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 1.70V. Computational calculations displayed positive radical spin densities at C2 positions for DTTs and negative for their dimers.

Selective syntheses of 3,4-vinylenedithiathiophenes (VDTTs) and dithieno[2,3-b:2',3'-d]thiophenes (DTTs), having Ph, 4-CH3OC6H4, 4-BrC6H4, 4-NO2C6H4 and 4-(CH3)(2)NC6H4 groups, were achieved through the reaction of 1,8-diketone with phosphorus decasulfide (P4S10). The reaction could be shifted between VDTT and DTT by adding base (sodium bicarbonate) or acid (para-toluenesulfonic acid), respectively, to the reaction mixture. While the VDTTs were obtained in moderate yields, an important achievement has been made with the syntheses of the DTTs, obtaining them in higher yields compared with the previous report. Polymers of the VDTTs, which are the analogues of ethylenedioxythiophene, EDOT, were prepared using FeCl3. Unfortunately, all attempts for their electropolymerization failed. Spin density calculations revealed that none of the VDTTs had a significant positive spin density at the 'alpha' carbon atoms of the thiophene ring. Considering their solubility and functional groups, which could be further derivatized, they are useful building blocks for the preparation of new organic materials. (C) 2011 Elsevier Ltd. All rights reserved.

Synthesis of 4-cyanophenylvinylenedithiathiophene, which is an analogue of ethylenedioxythiophene (EDOT), has been described. The synthesis was achieved by applying 1,8-diketone ring formation reaction occurring between 1,8-diketone and phosphorus decasulfide in boiling toluene. The target compound was characterized by cyclic voltammetry (CV), UV spectroscopy, and theoretical studies. Unlike the analogues similarly carrying phenyl groups substituted with other functional groups such as -OMe, -Br, -NO2, neither electrochemical polymerization attempts nor chemical polymerization efforts with ferric chloride(III) (FeCl3) succeeded in yielding any products. Results of spin density calculations revealed that the molecule did not have enough electron spin densities at the "alpha" carbons of the thiophene part. Moreover, during the polymerization attempt with FeCl3. as the nitrile nitrogen could form complex with iron, spin density calculation was also performed for protonated form of the monomer, which indicated that the "alpha" carbons of the molecule had even lower spin densities. (C) 2011 Elsevier B.V. All rights reserved.

3,5-Dithiophene-2-yldithieno[3,2-b;2',3'-d]thiophene (Thy(2)DTT) and ethylenedioxythiophene (EDOT) were electro-copolymerized on glassy carbon electrode (GCE) in 0.1 M sodium perchlorate (NaClO4)/acetonitrile (ACN)/dichloromethane (CH2Cl2) (8:2) solution. Poly(Thy(2)DTT-co-EDOT)/GCE thin film was characterized by various techniques, such as Cyclic Voltammetry (CV), Fourier Transform Infrared Spectroscopy - Attenuated Transmittance Reflectance (FTIR-ATR), Scanning Electron Microscopy - Energy Dispersive X-ray analysis (SEM-EDX) and Electrochemical Impedance Spectroscopy (EIS). The effects of monomer mole fractions (mole fraction, X-Thy2DTT = n(Thy2DTT/nEDOT) + n(Thy2DTT)) (0.5, 0.66 and 0.83) during the preparation of modified electrodes were examined by EIS. Capacitive behaviors of the modified GCE were defined via Nyquist, Bode-magnitude, Bode-phase and Capacitance plots. The circuit model was used to fit the theoretical and experimental data through Kramers-Kronig Transform test. The lowest frequency capacitance (C-LF) value was obtained as C-LF = 0.89 mFcm(-2) for poly(Thy(2)DTT). However, the highest C-LF was obtained for the copolymer as C-LF = 1.11 mFcm(-2) for X-Thy2DTT = 0.66 and 0.83. Potential application of the copolymer could be energy-storage devices.

A conducting polymer of 3,5-diphenyl-2.6-dithiophene-2-yl-dithieno[3.2-b;2'3'-dithiophene (Thy(2)Ph(2)DTT was synthesized by potentiodynamic method in dichloromethane (DCM)/acetonitrile (AN) (1/1)-NaClO4/LiClO4 (0.1:0.1 M) solvent-electrolyte mixture. The resulting polymer was characterized via cyclic voltammetry (CV). Fourier transform infrared (FOR) and UV-Vis spectroscopy. Its dual type electrochromic device (ECD) with PEDOT was constructed. Spectroelectrochemical and electrochromic properties of the polymer film and the device were investigated in detail. A potential range of 0.0-2.0 V was found to be suitable for operating the P(Thy(2)Ph(2)DTT)/PEDOT device between red and blue colors. The device displayed good open circuit memory and stability. Properties of Thy(2)Ph(2)DTT and P(Thy(2)Ph(2)DTT) were compared with 3,5-diphenyldithieno[3,2-b;2',3'-d]thiophene (Ph2DTT) and its polymer P(Ph2DTT), reported previously, which revealed that introduction of thiophenes to the peripherals of Ph2DTT improved the properties of the corresponding polymer. (C) 2012 Elsevier B.V. All rights reserved.

Electropolymerization of 3,5-bis(4-bromophenyl)dithieno[3,2-b;2',3'-d]thiophene, having a mild electron-withdrawing bromine atom attached to the para position of the two phenyl groups of dithienothiophene, was performed, utilizing a potentiodynamic method. The resultant homopolymer was characterized by cyclic volyammetry, fourier transform infrared and ultraviolet-visible spectroscopy. Spectroelectrochemical and electrochromic properties were investigated and a device was constructed with polyethylenedioxythiophene to understand the characteristics in detail, which had the potential range of 0.0-2.0 V for operating the device between green and blue colors. It had a good optical contrast of 18% with a switching time of less than a second. Moreover, open circuit memory and stability of the device were investigated. (C) 2011 Elsevier B.V. All rights reserved.

The mechanism of formation of dithieno[3,2-6:2',3'-d]thiophene (DTT) through the reaction of 1,8-diketone, 4,5-bis(benzoylmethylthio)thiophene with P4S10 was examined in detail by employing DFT method at B3LYP/6-311+G(d,p) level. Two mechanisms were considered. The first one included two parts (i) transformation of the 1,8-diketone, 4,5-bis(benzoylmethylthio)thiophene to the dithione by the reaction of P4S10 with the carbonyl groups and (ii) cyclization of the dithione to the final product, DTT, through an intramolecular reaction of the thiophene with thiones. The second mechanism consists of an initial attack of the carbonyl oxygen to the phosphorus atom of P4S10 followed by cyclization via an intramolecular attack from the thiophene ring to the highly electrophilic carbons connected to the oxygens to form DTT. According to the calculated Gibbs free energies of the studied paths, the second mechanism is more favorable than the first one and both pathways proceed in a stepwise manner. (C) 2011 Elsevier Ltd. All rights reserved.

Electropolymerization of 3.5-bis(4-methoxyphenyl)dithieno[3,2-b;2',3'-d]thiophene BMPhDTT, having strong electron-donating methoxy groups, was performed, utilizing potentiodynamic method. The homopolymer was characterized by cyclic voltammetry (CV), Fourier transform infrared (FTIR) and UV-vis spectroscopy. Spectroelectrochemical and electrochromic properties of the homopolymer film were investigated and a PBMPhDTT/PEDOT device was constructed to understand its characteristics in detail. It was revealed that the potential range of 0.0-2.0V is suitable for operating the device between yellow and blue colors. It indicated a good open circuit memory and stability. (C) 2010 Elsevier B.V. All rights reserved.

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