Benzotriazole Unit Research Articles

Interactions of 2-phenyl-benzotriazole xenobiotic compounds with human Cytochrome P450-CYP1A1 by means of docking, molecular dynamics simulations and MM-GBSA calculations

2-phenyl-benzotriazole xenobiotic compounds (PBTA-4, PBTA-6, PBTA-7 and PBTA-8) that were previously isolated and identified in waters of the Yodo river, in Japan (Nukaya et al., 2001; Ohe et al., 2004; Watanabe et al., 2001) were characterized as powerful pro-mutagens. In order to predict the activation mechanism of these pro-mutagens, we designed a computational biochemistry protocol, which includes, docking experiments, molecular dynamics simulations and free energy decomposition calculations to obtain information about the interaction of 2-phenyl-benzotriazole molecules into the active center of cytochrome P450-CYP1A1 (CYP1A1). Molecular docking calculations using AutoDock Vina software shows that PBTAs are proportionally oriented in the pocket of CYP1A1, establishing π-π stacking attractive interactions between the triazole group and the Phe224, as well as, the hydrogen bonds of the terminal NH2 over the benzotriazole units with the Asn255 and Ser116 amino acids. Molecular dynamics simulations using NAMD package showed that these interactions are stable along 100.0 ns of trajectories. Into this context, free binding energy calculations employing the MM-GBSA approach, shows that some differences exists among the interaction of PBTAs with CYP1A1, regarding the solvation, electrostatic and van der Waals interaction energy components. These results suggest that PBTA molecules might be activated by CYP1A1. Thus, enhancing their mutagenicity when compared with the pro-mutagen parent species.

Porphyrin sensitizers containing an auxiliary benzotriazole acceptor for dye-sensitized solar cells: Effects of steric hindrance and cosensitization

Dye-sensitized solar cells (DSSCs) have attracted intensive attention in developing photovoltaic devices for employing solar energy. For developing panchromatic and efficient porphyrin sensitizers, it has been demonstrated to be an effective approach to introduce an electron-withdrawing benzothiadiazole unit as an extra electron acceptor. In contrast, the structurally similar benzotriazole moiety remains relatively unknown in this respect. In this work, we have synthesized a novel porphyrin dye containing an extra electron acceptor of benzotriazole. Photophysical and electrochemical investigations revealed red-shifted absorption and a narrower band gap induced by the benzotriazole unit. Thus, a reasonable efficiency of 8.39% has been achieved with a Jsc of 17.00 mA cm−2 and a Voc of 712 mV. On this basis, to investigate the effect of the dihedral angle between the benzotriazole and the adjacent phenylene ring, one or two methyl groups were attached to the ortho-positions of the phenylene ring. As a result, the enlarged torsion angles induce poor electronic coupling between the LUMO of the dyes and TiO2, resulting in lower efficiencies of 6.61% and 3.62%, respectively. With the purpose to further improve the efficiencies, coadsorption and cosensitization approaches were employed. And the efficiencies have been successfully elevated to 9.32%, 8.49% and 7.34%, respectively. These results demonstrate the effectiveness of incorporating an auxiliary benzotriazole acceptor into porphyrin dyes on achieving extended light-harvesting wavelength ranges and illustrate the importance of avoiding severe torsion within the acceptor part of the porphyrin dyes. In contrast to the commonly used cosensitizers with absorption peaks lying in the absorption valley between the Soret band and the Q bands of porphyrin dyes (500–600 nm), the utilization of an organic dye with broad absorption in this work has been demonstrated to be effective for improving the efficiencies despite the fact that its absorption peak at 450 nm largely overlaps with the Soret band of the porphyrin dyes. These results provide an alternative approach for developing cosensitizers for porphyrin dyes.

Two wide-bandgap fluorine-substituted benzotriazole based terpolymers for efficient polymer solar cells

In this work, the fluorine substituted benzotriazole (FBTz) unit is introduced into terpolymers for the first time. FBTz as an acceptor unit was added to the terpolymers of PTT-FBTz and PTTz-FBTz, in which the bithiophene (biTh) unit is used as the donor unit and thieno[3,2-b]thiophene (TT) or thiazolo[5,4-d]thiazole (TTz) is adopted as a third component, respectively. Compared to PTT-FBTz with TT as the third component, PTTz-FBTz with TTz showed pronounced aggregated shoulder peaks both in solution and film absorption spectra. Electrochemical cyclic voltammetry (CV) shows PTTz-FBTz possesses both lower HOMO/LUMO level than PTT-FBTz due to the higher electronegativity of nitrogen atoms in TTz unit. Subsequently, the bulk-heterojunction polymer solar cells (PSCs) based on PTTz-FBTz show a higher power conversion efficiency of 7.03%, which is much higher than those of PTT-FBTz based devices (PCE = 2.63%). The enhancement of photovoltaic performance based on PTTz-FBTz is mainly attributed to the deeper highest occupied molecular orbital (HOMO) level, higher carrier transport and better molecular packing.

Synthesis and luminescence properties of cyclometalated iridium(III) complexes incorporating conjugated benzotriazole units

The stepwise synthesis of imidazo[4,5-f]-1,10-phenanthroline-based ligands that incorporate conjugated benzotriazole units are described. Corresponding cyclometalated Ir(III) complexes of the type [Ir(CˆN)2(L)]BF4 (where CˆN = cyclometalating ligand; L = phenanthroline type ligand) are reported. The complexes were characterized using a variety of techniques, including IR, NMR, UV-vis. spectroscopies, mass spectrometry and cyclic voltammetry. The [Ir(ppy)2(L)]BF4 complexes display luminescence in the visible region with the benzotriazole variants showing blue shifted emission around 495 nm. Supporting TD-DFT calculations predict that a mixture of MLCT and LLCT character may contribute to the HOMO-LUMO transition of the benzotriazole derivatives.

A new random D-A copolymer based on two different benzotriazole units as co-acceptors for polymer solar cells

In this work, two different benzotriazole derivatives (BTAZT and BTAZF) have been chosen as co-acceptors with a BDTT donor to build a new random D-A copolymer (PBTAZT-F) for polymer solar cells. Compared with two mono-acceptor (BTAZT or BTAZF) based homogeneous copolymers (PBTAZT and PBTAZF) as well as their physical-blend polymer (PBTAZT/PBTAZF), PBTAZT-F shows much broader absorption band with a larger full-width half-maxima (FWHM) in 400–750 nm due to good complementary of the intramolecular charge transfer absorption from two kinds of D-A structures in single unit, indicating that it can exhibit more efficient light-capturing ability in the visible region. PBTAZT-F based device shows the highest Jsc among all the polymers, which is attributed to its broad absorption as well as relatively large and balanced charge transport. Thus, it gives the best PCE of 5.58% with a Jsc of 11.28 mA cm−2, a Voc of 0.84 V and a FF of 58.60%.

Synthesis and structures of six closely related N-[3-(2-chlorobenzoyl)-5-ethylthiophen-2-yl]arylamides, together with an isolated reaction intermediate: order versus disorder, molecular conformations and hydrogen bonding in zero, one and two dimensions.

Six closely related N-[3-(2-chlorobenzoyl)-5-ethylthiophen-2-yl]arylamides have been synthesized and structurally characterized, together with a representative reaction intermediate. In each of N-[3-(2-chlorobenzoyl)-5-ethylthiophen-2-yl]benzamide, C20H16ClNO2S, (I), N-[3-(2-chlorobenzoyl)-5-ethylthiophen-2-yl]-4-phenylbenzamide, C26H20ClNO2S, (II), and 2-bromo-N-[3-(2-chlorobenzoyl)-5-ethylthiophen-2-yl]benzamide, C20H15BrClNO2S, (III), the molecules are disordered over two sets of atomic sites, with occupancies of 0.894 (8) and 0.106 (8) in (I), 0.832 (5) and 0.168 (5) in (II), and 0.7006 (12) and 0.2994 (12) in (III). In each of N-[3-(2-chlorobenzoyl)-5-ethylthiophen-2-yl]-2-iodobenzamide, C20H15ClINO2S, (IV), and N-[3-(2-chlorobenzoyl)-5-ethylthiophen-2-yl]-2-methoxybenzamide, C21H18ClNO3S, (V), the molecules are fully ordered, but in N-[3-(2-chlorobenzoyl)-5-ethylthiophen-2-yl]-2,6-difluorobenzamide, C20H14ClF2NO2S, (VI), which crystallizes with Z' = 2 in the space group C2/c, one of the two independent molecules is fully ordered, while the other is disordered over two sets of atomic sites having occupancies of 0.916 (3) and 0.084 (3). All of the molecules in compounds (I)-(VI) exhibit an intramolecular N-H...O hydrogen bond. The molecules of (I) and (VI) are linked by C-H...O hydrogen bonds to form finite zero-dimensional dimers, which are cyclic in (I) and acyclic in (VI), those of (III) are linked by C-H...π(arene) hydrogen bonds to form simple chains, and those of (IV) and (V) are linked into different types of chains of rings, built in each case from a combination of C-H...O and C-H...π(arene) hydrogen bonds. Two C-H...O hydrogen bonds link the molecules of (II) into sheets containing three types of ring. In benzotriazol-1-yl 3,4-dimethoxybenzoate, C15H13N3O4, (VII), the benzoate component is planar and makes a dihedral angle of 84.51 (6)° with the benzotriazole unit. Comparisons are made with related compounds.

Synthesis and characterization of polyelectrolytes based on benzotriazole backbone

Suzuki coupling and Ni-catalyzed Yamamoto polymerizations were used to prepare conjugated polyelectrolytes based on n-type benzothiadiazole and benzotriazole unit backbone via a one-step synthesis, which started from their monomers with charged pendant ends. PBTBTz-SO3Na synthesized by Suzuki coupling polymerization showed a high M n value of 94 kDa, starting from the bilateral brominated benzotriazole and diboronic ester benzothiadiazole. The PBTBTz-SO3Na revealed aggregation phenomenon at the status of diluted solutions at optical absorption spectroscopy results. Dynamic light scattering (DLS) measurement provided evidence of negative solvatochromic effects of PBTBTz-SO3Na chains in solvents with lower polarity. While, PBTz-PyrBr, PBTz-TMABr, and PBTz-SO3Na which synthesized from Ni-catalyzed Yamamoto polymerizations of bilateral brominated benzotriazole units revealed higher molecular weight with PBTz-PyrBr, M n = 112 kDa; PBTz-TMABr, M n = 157 kDa; and PBTz-SO3Na, M n = 172 kDa, respectively. The ionic pendant groups of monomers have influence on the molecular weight of polymer based on benzotriazole backbone. The optical absorption spectroscopy and DLS measurements presented the negative solvatochromic effects of cationic-CPEs, PBTz-PyrBr, and PBTz-TMABr. Moreover, the UV-vis absorption of PBTz-TMABr displayed higher wavelength of solution (0.0167 mg/mL) than that of film, which was coated from its solution with concentration of 5 mg/mL. These studies displayed insights into the role of pendant ionic functionalities on the molecular weight and optoelectronic properties of the CPEs, which may find application in optoelectronic devices.

Efficient All-Polymer Solar Cells Based on Conjugated Polymer Containing an Alkoxylated Imide-Functionalized Benzotriazole Unit

We developed a novel wide-bandgap conjugated polymer PTzBI-O based on an alkoxylated electron-deficient monomer 4,8-di(thiophen-2-yl)-[1,2,3]triazolo[4,5-f]isoindole-5,7(2H,6H)-dione (TzBI-O). Regarding that of alkyl-substituted imide-functionalized benzotriazole (TzBI) unit, the incorporation of oxygen atom into the substitution of TzBI-O increased the electronegativity. The resulting polymer PTzBI-O exhibited an absorption onset of 708 nm, corresponding to a bandgap of 1.75 eV. The PTzBI-O:N2200 blend exhibited strong aggregation in toluene solution, resulting in the enhanced absorptivity in thin film compared to those of equivalent films processed with chlorinated solvents. The fabricated all-polymer solar cell based on PTzBI-O:N2200 blend film processed with toluene exhibited an impressive power conversion efficiency of 7.91%. The higher efficiency of the toluene-processed device than those based on films processed with chlorinated solvents can be attributed to more effective charge dissociation, triv...

Thieno[3,2-b]pyrrolo-Fused Pentacyclic Benzotriazole-Based Acceptor for Efficient Organic Photovoltaics

A novel nonfullerene small molecular acceptor (BZIC) based on a ladder-type thieno[3,2-b]pyrrolo-fused pentacyclic benzotriazole core (dithieno[3,2-b]pyrrolobenzotriazole, BZTP) and end-capped with 1,1-dicyanomethylene-3-indanone (INCN) has been first reported in this work. Through introducing multifused benzotriazole and INCN, BZIC could maintain a high-lying lowest unoccupied molecular orbital (LUMO) energy level of -3.88 eV. Moreover, BZIC shows a low optical bandgap of 1.45 eV with broad and efficient absorption band from 600 to 850 nm due to increased π-π interactions by the covalently locking thiophene and benzotriazole units. A power conversion efficiency of 6.30% is delivered using BZIC as nonfullerene acceptor and our recently synthesized hexafluoroquinoxaline-based polymer HFQx-T as donor. This is the first time to synthesize mutifused benzotriazole-based molecules as nonfullerene electron acceptor up to date. The preliminary results demonstrate that the mutifused benzotriazole derivatives hold great potential for efficient photovoltaics.

Physico-chemical characteristics of Composites material Based on Sulfonated Cyclone Fibre Cellulose and Benzotriazole

Composites material based on sulfonated cyclone fibre cellulose (SCFC) and benzotriazole (Btri) have been prepared. Cyclone fibre cellulose (CFC) was sulfonated with trimethylsilyl chlorosulfonate (TMSCS), with high degree of sulfonation (150%). The composites material, SCFC-Btri were prepared by doping of benzotriazole in various mole ratios (0.125, 0.25 and 0.5). FTIR spectrum has confirmed the ionic interaction between sulfonic acid from sulfonated cyclone fibre cellulose and benzotriazole units. Thermogravimetric analysis (TGA) showed that the composites material was thermally stable up to 150 °C. The results showed that methanol permeability of the composite material was lower than pristine Nafion112. Activation energy obtained for the materials are 0. 106 eV, 0.144 eV and 0.137 eV for SCFC-Btri mole ratios 0.125, 0.25 and 0.5 respectively, composites material was expected to be used as raw material in the fuel cell.

Wide Band Gap and Highly Conjugated Copolymers Incorporating 2-(Triisopropylsilylethynyl)thiophene-Substituted Benzodithiophene for Efficient Non-Fullerene Organic Solar Cells

Recent years have seen a rapid progress in the power conversion efficiencies (PCEs) of non-fullerene polymer solar cells (NF PSCs). However, the donor materials accordingly used are typical low or medium band gap polymers, some of which possess badly overlapped absorption spectra relative to the low band gap n-type acceptors, for example, 3,9-bis(2-methylene-(3-(1,1-dicyanomethylene)indanone)-5,5,11,11-tetrakis(4-hexylphenyl)dithieno[2,3-d:2',3'-d']-s-indaceno[1,2-b:5,6-b']dithiophene) (ITIC). To obtain polymers simultaneously owning a wide band gap, a highly extended π-conjugation system, and a low-lying highest occupied molecular orbital (HOMO), a polymer (PBDTSi-TA) incorporating 2-(triisopropylsilylethynyl)thiophene substituted benzodithiophene (BDTSi) and fluorinated benzotriazole (FTAZ) units was designed and synthesized. PBDTSi-TA (Egopt = 1.92 eV) exhibits strong molecular aggregation properties and a lower-lying HOMO energy level compared to its structural analogues. When blended with ITIC and after device optimization with solvent vapor annealing in combination with a developed PDIN/BCP/Ag cathode structure, PSCs yielded a PCE of 7.51%, with Voc = 0.96 V. Moreover, a rather small energy loss (Eloss) of 0.6-0.63 eV was determined. For comparison, another polymer (PBDTSi-Qx) with a more-electron-deficient quinoxaline-based acceptor unit was also synthesized and applied to NF PSCs. Charge generation rate, exciton dissociation probabilities, dark leakage current, nanoscale morphology, and charge carrier mobilities have been evaluated to probe the reasons for the differentiated performances. The results suggest that PBDTSi-TA is a promising donor material for NF PSCs, and the molecular design strategy demonstrated here would be helpful for pursuing high-performance polymers for PSCs.

Design of a thiophene-fused benzotriazole unit as an electron acceptor to build D–A copolymers for polymer solar cells

A new electron-acceptor, thiophene-fused benzotriazole (BTAZT), is designed for the first time to construct donor–acceptor copolymers with bithienyl substituted benzo[1,2-b:4,5-b′]dithiophene (BDTT) as an electron-donor unit for polymer solar cells (PSCs).

Constructing D–A copolymers based on thiophene-fused benzotriazole units containing different alkyl side-chains for non-fullerene polymer solar cells

A series of D–A copolymers based on thiophene fused benzotriazole (BTAZT) and 4,8-bis(4-fluorothiophen-2-yl)benzo[1,2-b:4,5-b′]dithiophene (BDTFT) units containing different alkyl side-chains have been constructed as electron-donating materials for non-fullerene PSCs.

Synthesis of fluorinated benzotriazole (BTZ)- and benzodithiophene (BDT)-based low-bandgap conjugated polymers for solar cell applications

A series of donor–acceptor (D–A) polymers (P1–P3) based on benzodithiophene (BDT) and electron-accepting benzotriazole (BTZ) units containing thiophene linkers with/without alkyl side-chains were designed and synthesized via Stille coupling polymerization method. The effects of polymers with multiple fluorinated BTZ groups on their thermal, optical, electrochemical, and photovoltaic properties were investigated. These polymers possessed the highest occupied molecular orbital (HOMO) levels ranged −5.38 to −5.6 eV and the lowest unoccupied molecular orbital (LUMO) levels ranged −3.55 to −3.57 eV, which covered broad absorption ranges with low optical bandgaps. The bulk heterojunction (BHJ) polymer solar cell (PSC) devices containing an active layer of D-A polymers blended with different weight ratios of electron-acceptor [6,6]-phenyl-C71-butyric acid methyl ester (PC71BM) were explored under 100 mW cm−2 of AM 1.5 white-light illumination, where the maximum power conversion efficiency (PCE) value of 3% (with Jsc = 7.70 mA/cm2, FF = 54.04, and Voc = 0.72 V) was obtained in the PSC device consisting of polymer P3.

1-[({5-[(4-Methylphenoxy)methyl]-4-phenyl-4H-1,2,4-triazol-3-yl}sulfanyl)methyl]-1H-benzo[d][1,2,3]triazole

The title molecule, C23H20N6OS, adopts a cup-shaped conformation with the planes of the two benzene rings and the benzotriazole unit close to being parallel. The crystal packing features C—H...π(ring) and offset π–π stacking interactions.

Synthesis and characterization of benzodithiophene and benzotriazole-based polymers for photovoltaic applications.

Two high bandgap benzodithiophene–benzotriazole-based polymers were synthesized via palladium-catalysed Stille coupling reaction. In order to compare the effect of the side chains on the opto-electronic and photovoltaic properties of the resulting polymers, the benzodithiophene monomers were substituted with either octylthienyl (PTzBDT-1) or dihexylthienyl (PTzBDT-2) as side groups, while the benzotriazole unit was maintained unaltered. The optical characterization, both in solution and thin-film, indicated that PTzBDT-1 has a red-shifted optical absorption compared to PTzBDT-2, likely due to a more planar conformation of the polymer backbone promoted by the lower content of alkyl side chains. The different aggregation in the solid state also affects the energetic properties of the polymers, resulting in a lower highest occupied molecular orbital (HOMO) for PTzBDT-1 with respect to PTzBDT-2. However, an unexpected behaviour is observed when the two polymers are used as a donor material, in combination with PC61BM as acceptor, in bulk heterojunction solar cells. Even though PTzBDT-1 showed favourable optical and electrochemical properties, the devices based on this polymer present a power conversion efficiency of 3.3%, considerably lower than the efficiency of 4.7% obtained for the analogous solar cells based on PTzBDT-2. The lower performance is presumably attributed to the limited solubility of the PTzBDT-1 in organic solvents resulting in enhanced aggregation and poor intermixing with the acceptor material in the active layer.

Crystal structure of 1,3-bis-(1H-benzotriazol-1-yl-meth-yl)benzene.

The mol-ecular structure of the title compound, C20H16N6, contains two benzotriazole units bonded to a benzene nucleus in a meta configuration, forming dihedral angles of 88.74 (11) and 85.83 (10)° with the central aromatic ring and 57.08 (9)° with each other. The three-dimensional structure is controlled mainly by weak C-H⋯N and C-H⋯π inter-actions. The mol-ecules are connected in inversion-related pairs, forming the slabs of infinite chains that run along the [-110] and [110] directions.

Benzotriazole-containing donor–acceptor–acceptor type cyclometalated iridium(III) complex for solution-processed near-infrared polymer light emitting diodes

A novel near-infrared-emitting cyclometalated iridium(III) complex of (CH3OTPA-BTz-Iq)2Irpic containing benzotriazole unit with a donor–acceptor–acceptor (D-A-A) chromophore was synthesized and characterized. The optophysical, electrochemical and electroluminescent characteristics were primarily studied. A near-infrared emission peaked at 716 nm with a shoulder at 790 nm was exhibited in the (CH3OTPA-BTz-Iq)2Irpic dichloromethane solution at 298 K. In its optimized solution-processed polymer light-emitting diodes, a near-infrared electroluminescent emission peaked at 723 nm with a shoulder at 780 nm was observed with a maximum external quantum efficiency of 0.41% at 8.14 mA cm−2. This work indicates that introducing appropriate D and A units to develop D-A-A structure is an efficient approach to construct near-infrared-emitting iridium(III) complex in the polymer light-emitting diodes with suppressive efficiency roll-off.

Effects of Fluorination and Side Chain Branching on Molecular Conformation and Photovoltaic Performance of Donor–Acceptor Copolymers

The performance of donor–acceptor type conjugated polymers in photovoltaic devices is strongly dependent on the morphology of the thin film, which can be controlled by the substitution of various side groups on to the conjugated backbone. We investigate the effects of fluorination of the acceptor unit, and differences in the symmetry of alkyl side chain branching on the resulting photovoltaic device efficiency. Chemical variants of the donor–acceptor copolymer poly{4,8-bis[(triisopropylsilyl)ethynyl)benzo[1,2-b:4,5-b′]-dithiophene-alt-2-(heptadecan-9-yl)-4,7-bis(thiophen-2-yl)-2H-benzo[d][1,2,3]triazole} (PBDTBTz) are considered. Using Raman spectroscopy we find that the benzodithiophene-thiophene (BDT-T) interunit bond dihedral torsion is minimized by using a symmetrically branched alkyl side chain on the benzotriazole (BTz) unit. This leads to an increased quality of molecular packing, resulting in the highest hole mobility (∼3.8 × 10–3 cm2/(V s)) and overall device efficiency (∼5.5%). By contrast, fluo...

Semiconducting Polymers Consisting of Anthracene and Benzotriazole Units for Organic Solar Cells.

An alternating copolymer composed of 2,6-dibromo-9,10-bis(2-ethylhexyloxy)anthracene and benzotriazole units, poly(An-alt-BTz), was synthesized, through a Suzuki cross-coupling polymerization, for use in photovoltaic devices as a p-type electron donor. For the reduction of the bandgap energy of benzotriazole units, 5,5'-dibromo-2,2'-bithiophene, or 2,5-dibromothieno [3,2-b] thiophene units were introduced into the polymer. Poly(anthracene-co-benzotriazole-co-bithiophene(thienothiophene))s were synthesized using the same polymerization reactions. The measured optical bandgap energy of poly(anthracene-alt-benzotriazole) was 2.62 eV. As the contents of the flat comonomer units in the ter-polymers increased, the bandgap energies of the resulting polymers decreased up to 1.95 eV. The energy levels of the HOMO and the LUMO of the copolymers were determined from the cyclic voltammetry. Photovoltaic devices were fabricated with the polymers as electron donors and PC71 BM as an electron acceptor. One of the fabricated devices showed the maximum PCE of 0.74% with 0.57 V of VOC, 2.59 mA/cm2 of JSC, and 0.48 of FF under AM 1.5G (100 mW/cm2) condition.