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Sustainable energy storage materials are of increasing importance for new energy technologies to produce more intelligent, lighter, thinner and multifunctional power systems. In this study, copolymers of N-(4-(4-thieno[3,2-b]thiophene-3-ylphenyl)phenyl)-N-phenylbenzenamine (TTpTPA) and 3,4-ethylenedioxythiophene (EDOT) were synthesized electrochemically starting from different molar ratios of TTpTPA(T) and EDOT(E) (nT:nE). The copolymers obtained on the ITO surface, i.e. P(T10-1E), P(T5-1E), P(T5-2E), P(T1-1E), were directly used to design electrochromic energy storage devices (ECESDs). Electrochemical characterizations suggested that the copolymerization improved the capacitances of PTTpTPAand PEDOTup to the highest value of 21 mF cm−2with the copolymer P(T1-1E). It exhibited a color change from purple to blue during charging and discharging processes. Additionally, P(T5-2E)displayed a remarkable multicolor change as a color cartel, i.e. red, yellow, green, gray and blue, during the oxidation with a high color efficiency of 161 cm2C−1. Finally, the flexible symmetric device prototype of P(T1-1E)possessed a good practical application for next generation energy storage devices with its high energy and high-power densities.

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. Copolymers of 4‐thieno[3,2‐b]thiophen‐3‐ylbenzonitrile, having electron withdrawing cyano substituent, with rigid anthracene and biphenyl units, were synthesized by successive Palladium (0) catalyzed Suzuki polymerization. Their electronic and optical properties were investigated by UV–Vis spectroscopy, fluorescence spectroscopy, CV, and solvatochromic studies with different solvents. They demonstrated to be good candidates for electronic applications.

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 (TBAPF6). Then, a third polymer as a co‐polymer (P3) was synthesized through electropolymerization of a mixture of the monomers M1and M2in 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, P2and P3exhibited 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 P3had the highest current density, having lower resistance. Electropolymerizationof a mixture of dithienothiophene and bithiazole has been realized and electrochemical properties have been explained.

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. In this article, the photoinduced polymerization of thieno[3,4‐b]thiophenes having electronically different substituents is reported via the step‐growth mechanism. Upon irradiation at 350 nm of these monomers in the presence of diphenyl iodonium salt as photo‐oxidant successive electron transfer, proton release resulted in the formation of the corresponding oligomers.

Flavonoids are naturally occurring phenolic compounds named as 2-phenyl-1-benzopyran- 4-one and classified into several subclasses according to their basic chemical structures such as flavones, flavonols, flavanones, flavanonols, and flavanols. Among them, flavonols (3-hydroxyflavone), containing a 3-hydroxyl group in association with its 4-keto group and double bond between 2- and 3- carbon atoms, have the best electron conjugated skeleton in flavonoid family, providing several resonance structures and chelating ability, through which various pharmacological activities such as antiviral, antitumour, anti-inflammatory, anticholinesterase, cytotoxicity and particularly high antioxidant activity are demonstrated. They prevent generation of free radicals and are used as food preservatives. Their strong electron conjugation provides them with fluorescent property, which make them used as imaging agents for therapeutic purpose.

Thiophene-based π-conjugated organic small molecules and polymers are the research subject of significant current interest owing to their potential use as organic semiconductors in material chemistry. Despite simple and similar molecular structures, the hitherto reported properties of thiophene-based organic semiconductors are rather diverse. Design of high performance organic semiconducting materials requires a thorough understanding of inter- and intra-molecular interactions, solid-state packing, and the influence of both factors on the charge carrier transport. In this chapter, thiophene-based organic semiconductors, which are classified in terms of their chemical structures and their structure–property relationships, are addressed for the potential applications as organic photovoltaics (OPVs), organic field-effect transistors (OFETs) and organic light emitting diodes (OLEDs).

The novel monomer, 4‐(2‐(4‐(bis(4‐(thiophen‐2‐yl)phenyl)amino)phenyl)‐5‐(thiophen‐2‐yl)thieno[3,2‐b]thiophen‐3‐yl)benzonitrile, is synthesized by applying Suzuki coupling reaction and electropolymerized directly onto indium tin oxide coated glass electrode surface to obtain a conjugated microporous polymer of [Th3CNTT–TPA] (P[Th3CNTT–TPA]). The morphology and structure of the polymer film are characterized by atomic force microscopy, Fourier transform infrared, and UV–visible spectroscopies. Electrochemical properties are studied using cyclic voltammetry, electrochemical impedance spectroscopy, galvanostatic charge–discharge, and chronoamperometric measurements. Its gravimetric capacity and capacitance values are measured to be 65 and 235 F g−1at a current density of 3 A g−1, respectively. It shows high energy and power densities of 65 and 32.5 kWh kg−1, respectively, and exhibits high coloration efficiency of 513 C−1cm2in visible region, switching between yellow and grey colors. Three different electrochromic–supercapacitor devices, that is, one symmetrical (energy storage device (ESD)1) and two asymmetrical, using poly(3,4‐ethylendioxythiophen) (ESD2) and poly(3,4‐propylenedioxypyrrole) (ESD3) as counter electrodes, are fabricated. The asymmetrical device, ESD3, demonstrats better capacity and stability. Regarding the cyclic stability and electrochromic‐energy‐storage properties, P[Th3CNTT–TPA] can be considered as a good candidate for multifunctional applications. Energy‐storage properties of symmetrical and asymmetrical devices (energy storage device (ESD)1, ESD2, ESD3) are prepared from newly synthesized polymer, P[Th3CNTT–TPA], that has high coloration efficiency of 513 C−1cm2are compared. It is suggested in the results that the asymmetrical device, ESD3, demonstrats better capacity and energy density of 450 F g−1and 125 Wh kg−1, respectively.

Energy storage properties of symmetrical and asymmetrical devices (ESD1, ESD2, ESD3) prepared from newly synthesized polymer, P[Th3CNTT‐TPA], which has a high coloration efficiency of 513 C−1cm2, were compared. The results suggest that the asymmetrical device, ESD3, demonstrates better capacity and energy density of 450 Fg−1and 125 Whkg−1, respectively. More details can be found in article number 2300015, Esma Sezer and co‐workers.

Background: Flavones, are a class of naturally occuring polyphenolic compounds which have 2-phenylchromen-4-one structure. Various studies showed that flavones have several pharmacological activities such as antioxidant, anti-inflammatory, antimicrobial, cytotoxic, antitumour and antiallergic. In the present study, 3-hydroxyflavones also called flavonols, posessing 4'-dialkylamino moiety were synthesized, and their antioxidant and anticholinesterase activities were investigated by comparison with unmodified 3-hydroxflavone. Method: For investigation of antioxidant potential, radical scavenging assays (DPPH•, ABTS+_, O2-) were used along with CUPRAC and lipid peroxidation inhibitory assays, as well as anticholinesterase activity by Ellman method. Results: The best results were obtained for 4'-N,N-dimethyl flavonol (1) in both antioxidant and anticholinesterase activity tests, possibly due to its least steric hinderance effect. It exhibited remarkable DPPH free radical scavenging activity (2.43±0,09 μ ;g/mL) competing with a standard compound quercetin (2.10±0,10 μ ;g/mL). Moreover, the other tested flavonols also showed high antioxidant activities. Compounds 5 and 6 exhibited close IC50 values to those of compound 1. Conclusion: Antioxidant activity test results were found to be well correlated with anticholinesterase activity test results indicating possible role of antioxidant compounds in the treatment of Alzheimer’s disease.

3,5-Dithiophene-2-yldithieno[3,2-b;2',3'-d]thiophene (Thy2DTT) 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(Thy2DTT-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, XThy2DTT = nThy2DTT/nEDOT + nThy2DTT) (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 (CLF) value was obtained as CLF = 0.89 mFcm[?]2 for poly(Thy2DTT). However, the highest CLF was obtained for the copolymer as CLF = 1.11 mFcm[?]2 for XThy2DTT = 0.66 and 0.83. Potential application of the copolymer could be energy-storage devices.

Poly(3‐hydroxy undec‐10‐enoate) (PHU) was synthesized by feeding Pseudomonas oleovarans with 10‐undecenoic acid and nearly 100% hydroxylation of double bonds of PHU was achieved by hydroboration–oxidation reaction using 9‐borobicyclononane. The disappearance of vinyl signals of PHU in proton and 13C NMR spectra was observed. Acetylation of hydroxylated PHU was conducted for molecular weight measurements. Molecular weight and polydispersity of hydroxylated PHU were found to be 10,000 and 1.23, respectively, while that of the originals was 32,000 and 2.42. Decomposition temperatures of original and hydroxylated PHU were 280 and 200°C, respectively. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 2132–2139, 2005

3-Hydroxychromones 3HCs are fluorescent dyes, which respond to solvent perturbations by shifts and changes in the relative intensity of the two well-separated bands in the emission spectra. These bands originate from an excited state intramolecular proton transfer ESIPT reaction, which can be modulated by different factors, including modifications in the 3HC chromophore. In view of the great importance of 3HCs as prospective basic elements of molecular sensors, we have performed the first systematic study on the correlation between 3HC structure and spectroscopic properties. Two series of known and newly synthesized 2-phenyl-3-hydroxychromones and 2-2-benzobfuranyl-3-hydroxychromones with varied electron-donor substituents, introduced on opposite sides of the chromophore, were compared in solvents of different polarities. The substitution of 2-phenyl for 2-2-benzobfuranyl and introduction of electron donors on the 2-aryl group not only shift the absorption and fluorescence spectra to the red, but also strongly modulate the ESIPT behavior, resulting in a dramatic increase of the intensity ratio of the two emission bands, INIT. In contrast, introduction of a 7-methoxy group results in exactly the opposite spectroscopic effects. All the studied 3HC dyes demonstrate a linear increase in lnINIT with the solvent polarity parameter ET30. Substitution of 2-phenyl for 2-2-benzobfuranyl or introduction of electron donors on the 2-aryl group in 3HC increases the sensitivity of their INITratio to solvent polarity and shifts the optimal range of ratiometric polarity sensing to less polar solvents. The opposite effects are observed for 7-methoxy derivatives. These results allow a new generation of two-band fluorescent sensors based on 3HC that operate by the ESIPT mechanism to be proposed. By proper substituents their photophysical and sensing properties can be tuned over broad ranges.

3-Hydroxychromones (3HCs) are fluorescent dyes, which respond to solvent perturbations by shifts and changes in the relative intensity of the two well-separated bands in the emission spectra. These bands originate from an excited state intramolecular proton transfer (ESIPT) reaction, which can be modulated by different factors, including modifications in the 3HC chromophore. In view of the great importance of 3HCs as prospective basic elements of molecular sensors, we have performed the first systematic study on the correlation between 3HC structure and spectroscopic properties. Two series of known and newly synthesized 2-phenyl-3-hydroxychromones and 2-(2-benzo[b]furanyl)-3-hydroxychromones with varied electron-donor substituents, introduced on opposite sides of the chromophore, were compared in solvents of different polarities. The substitution of 2-phenyl for 2-(2-benzo[b]furanyl) and introduction of electron donors on the 2-aryl group not only shift the absorption and fluorescence spectra to the red, but also strongly modulate the ESIPT behavior, resulting in a dramatic increase of the intensity ratio of the two emission bands, I_N*/I_T*. In contrast, introduction of a 7-methoxy group results in exactly the opposite spectroscopic effects. All the studied 3HC dyes demonstrate a linear increase in ln(I_N*/I_T*) with the solvent polarity parameter E_T(30). Substitution of 2-phenyl for 2-(2-benzo[b]furanyl) or introduction of electron donors on the 2-aryl group in 3HC increases the sensitivity of their I_N*/I_T* ratio to solvent polarity and shifts the optimal range of ratiometric polarity sensing to less polar solvents. The opposite effects are observed for 7-methoxy derivatives. These results allow a new generation of two-band fluorescent sensors based on 3HC that operate by the ESIPT mechanism to be proposed. By proper substituents their photophysical and sensing properties can be tuned over broad ranges.

A simple and convenient synthesis of pyrido(2,3,4-kl)acridine (1), the main skeleton of some marine alkaloids, via cyclization and intramolecular nitrene insertion, is described. The importance of the planarity of the molecule during the nitrene insertion is explained.Key words: pyridoacridine, marine alkaloids, nitrene insertion, quinoline, quinolinone.

The crystal structure of ethyl bis(2,4-dinitrophenyl)acetate, determined by room temperature X-ray diffraction, shows that this crowded molecule contains two short intramolecular interactions between nitro oxygen atoms and electron deficient carbon atoms. One mimics an early stage of the nucleophilic addition to a carbonyl group (O...C, 2.730 Å), and the other mimics an early stage of a Michael reaction (O...C, 2.854 Å). Crystal data: C16H12N4O10, Mr= 420.29, a= 10.079(1), b= 11.139(1), c= 16.162(1) Å, β = 91.319(7)°, monoclinic, P21/c, Z= 4.

Reaction of 1,8-diketones 3with Lawesson's reagent 8resulted in the formation of five and six-membered rings 5–7, 18, depending on the nature of the substituents. Product 6is converted in two steps to the unsymmetric ‘ET’ analogue 20, containing an extra double bond.

AbstractThe effective size of bonded divalent sulfur in S…S contacts is a function of the orientation of the groups, with the shortest contacts occurring when the groups are coplanar. A lower limit for the loner is indicated by the structures of the 2-(1,3-benzodithiol-2-ylidenemethyl)-1,3-benzodithiolium and 2-(1,3-dithiolan-2-ylidenemethyl)-1,3-dithiolanium cations, 2 and 3. These show almost mmsymmetry with all four sulfur atoms involved in stabilisation of the positive charge. Short intramolecular sulfur… sulfur contact distances, 0.5–0.7 Å within the sum of traditional van der Waals radii, and maximised by in-plane angular distortions, indicate a lower limit to the effective size of the bonded divalent sulfur atom of ca. 1.45 Å.

A wide series of 10 new triphenylamine (TPA)/4,4′-dimethoxytriphenylamine (TPA(OMe)2)-functionalized thieno[3,2-b]thiophene (TT) fluorophores, 4a–eand 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.

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 P1 and P2, respectively, were obtained via electropolymerization. A third polymer (P3), a co‐polymer of the monomers M1 and M2, was also synthesized through electropolymerization. Their electronic and capacitor properties were investigated, and EIS measurements indicated that P3 had the highest current density, having lower resistance. More information can be found in the Full Paper by Turan Ozturk et al.

Syntheses of fully unsaturated 5,6-diphenyl[1,3]dithiolo[4,5-b][1,4]dithiine-2-thione and its coupling product, a fully unsaturated analogue of BEDT-TTF, have been achieved by a 1,8-diketone ring formation reaction.

The synthesis of a highly functionalized BEDT-TTF derivative containing phenyl-1,4-dithiin and 2,3-dihydroxybutane-1,4-dithio peripherals is described.

3,5-Dithiophene-2-yldithieno[3,2-b;2′,3′-d]thiophene (Thy2DTT) 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(Thy2DTT-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, XThy2DTT= nThy2DTT/nEDOT+ nThy2DTT) (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 (CLF) value was obtained as CLF= 0.89 mFcm−2for poly(Thy2DTT). However, the highest CLFwas obtained for the copolymer as CLF= 1.11 mFcm−2for XThy2DTT= 0.66 and 0.83. Potential application of the copolymer could be energy-storage devices.

A new catalyst is presented for the synthesis of 2‐substituted benzimidazoles or benzothiazoles from o‐phenylenediamine (I) or 2‐aminothiophenol (IV) and aldehydes under solvent‐free conditions.

Review: 448 refs.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access the actual ChemInform Abstract, please click on HTML or PDF.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.