24243-31-0

Upstream product

• 7333-07-5 2,2'-thenil 
• 3172-56-3 3,3'-bithiophene 
• 79-37-8 oxalyl dichloride 

Downstream Products

• 1546975-23-8 2-(p-octyloxyphenyl)-1-pentyldithieno[2',3':3,4:3'',2'':5,6]benzimidazole 

Relevant academic research and scientific papers

Charge Transfer Through Dithieno[2,3-a:3′,2′-c]phenazine: Effect of Substitution Pattern on the Optoelectronic Properties of Regioisomeric Luminophores

Two series of regioisomeric luminophores that contained a dithieno[2,3-a:3′,2′-c]phenazine (DTP) unit as an electron acceptor have been designed and synthesized. To investigate the effect of substitution pattern on the optoelectronic properties of these luminophores, electron donors (N,N-dihexylaniline or N,N-dihexyl-4-vinylaniline) were incorporated at the 2,5-, 8,11-, and 9,10-positions of the DTP unit. We found that the optoelectronic properties of the regioisomeric luminophores were greatly affected by the substitution pattern: functionalization at the 8,11-positions of the DTP unit was superior to the other two substitution patterns in extending the effective π-conjugation and strengthening the intramolecular charge-transfer interactions. Moreover, the insertion of vinyl groups between the DTP and N,N-dihexylaniline units narrowed the energy band-gap for isomers 4 and 5. However, hypsochromically shifted absorption and photoluminescence maxima were observed for isomeric luminophore 6, in which electron donors were substituted at the 2,5-positions of the DTP unit. These results should facilitate greater understanding of the structure-property relationships in regioisomeric semiconductors and present a new way to design optoelectronic materials with effective substitution patterns.

Syntheses and properties of thienyl-substituted dithienophenazines

A series of dithienophenazines with different lengths of the oligomeric thiophene units (quaterthiophenes and sexithiophenes) was synthesized. The thiophene and phenazine units act as electron donors and acceptors, respectively, resulting in characteristic absorption spectra. The optical spectra were calculated using time-dependent density functional theory at the B3LYP/TZVP level and verify the experimental data. Adsorption of the dithienophenazines on highly ordered pyrolytic graphite (HOPG) was investigated by scanning tunneling microscopy, showing that one of the compounds forms highly organized self-assembled monolayers.

Synthesis and characterization of dioctyloxybenzo[1,2- b:4,3- b ′]dithiophene-containing copolymers for polymer solar cells

A series of D-A copolymers containing dioctyloxybenzo[1,2-b:4,3-b′] dithiophene (BdT) donor unit and different acceptor unit of bithiazole (BTz), thiazolo[5,4-d]thiazole (TTz), dithienylylbenzothiadiazole (DTBT), and dithienyl-pyrrolo[3,4-c]pyrrole-1,4-dione (DPP), PBdT-BTz, PBdT-TTz, PBdT-DTBT, and PBdT-DPP, were synthesized for the application as donor materials in polymer solar cells (PSCs). Bandgaps and HOMO (the highest occupied molecular orbital) energy levels of the copolymers were tuned effectively by using different acceptor units from 2.01 and -5.16 eV for PBdT-BTz, to 1.91 and -5.19 eV for PBdT-TTz, 1.70 and -5.09 eV for PBdT-DTBT, and 1.41 and -5.01 eV for PBdT-DPP. The PSCs based on the blend of PBdT-TTz (with a lower HOMO of -5.19 eV) and PC70BM (1:3 w/w) exhibited a power conversion efficiency of 3.40% with a Jsc of 5.50 mA/cm2, a high Voc of 0.90 V, and a high FF of 68.7%.

Benzodithieno-imidazole based π-conjugated fluorescent polymer probe for selective sensing of Cu2+

π-Conjugated polymers appended with binding sites are of considerable interest as an evolving new class of heavy and toxic metal ion sensors through fluorescence quenching. In this study we describe the synthesis and characterization of a p-bromophenyl substituted benzodithieno-imidazole based soluble and rigid π-conjugated polymer with N and S donors exhibiting outstanding sensitivity towards Cu2+ by emission quenching through photoinduced electron transfer (PET). Detailed photophysical and ion sensing studies have been demonstrated to understand insight of the polymer-metal ion interaction which is responsible for selective fluorescence quenching. The corresponding polymer is also explored as a thin-film polymeric sensor towards Cu2+ as monitored by a photoluminescence study.

A Coplanar π-Extended Quinoxaline Based Hole-Transporting Material Enabling over 21 % Efficiency for Dopant-Free Perovskite Solar Cells

Developing dopant-free hole transporting materials (HTMs) is of vital importance for addressing the notorious stability issue of perovskite solar cells (PSCs). However, efficient dopant-free HTMs are scarce. Herein, we improve the performance of dopant-free HTMs featuring with a quinoxaline core via rational π-extension. Upon incorporating rotatable or chemically fixed thienyl substitutes on the pyrazine ring, the resulting molecular HTMs TQ3 and TQ4 show completely different molecular arrangement as well as charge transporting capabilities. Comparing with TQ3, the coplanar π-extended quinoxaline based TQ4 endows enriched intermolecular interactions and stronger π–π stacking, thus achieving a higher hole mobility of 2.08×10?4 cm2 V?1 s?1. It also shows matched energy levels and high thermal stability for application in PSCs. Planar n-i-p structured PSCs employing dopant-free TQ4 as HTM exhibits power conversion efficiency (PCE) over 21 % with excellent long-term stability.

Thiophene-rich fused-aromatic thienopyrazine acceptor for donor-acceptor low band-gap polymers for OTFT and polymer solar cell applications

Thiophene enriched fused-aromatic thieno[3,4-b]pyrazine systems were designed and employed to produce low band gap polymers (Eg = 1.0-1.4 eV) when copolymerized with fluorene and cyclopentadithiophene. The copolymers are mainly investigated for organic thin film transistor and organic photovoltaic applications. Molecular packing in the thin films of these polymers was investigated using Grazing incidence X-ray Scattering. Although both fluorene and cyclopentadithiophene polymers follow similar face to face π-π stacking, the latter polymers show much smaller lamellar d-spacings due to side-chain interdigitation between the lamellae. This lead to the higher charge carrier mobilities in cyclopentadithiophene polymers (up to 0.044 cm2/V.s) compared to fluorene polymers (up to 8.1 × 10-3 cm2/V.s). Power conversion efficiency of 1.4% was achieved using fluorene copolymer in solar cells with a fullerene derivative as an acceptor. Although the cyclopentadithiophene polymers show lower band gaps with higher absorption coefficients compared to fluorene copolymers, but the power conversion efficiencies in solar cells of these polymers are low due to their low ionization potentials. The Royal Society of Chemistry 2010.

Self-assembly of bistriazole BDT based bolaamphiphiles into SmA phase and helical organogels

Bistriazole benzo[1,2-b:4,3-b′]dithiophene (BDT) contained bolaamphiphiles have been synthesized via Sonogashira coupling and click reactions as key steps. For such compounds, the central bent bistriazole BDT core, the flexible methylene spacer led the rodlike core together with the terminal diol groups to twist to be U-shaped polar region. Micro-segregation of U-shaped polar region from the lipophilic chains generated a SmA phase. Furthermore, these compounds can act as super organogelators to gel different kinds of solvents with the lowest critical gelation concentration (CGC) of 0.2 mg/ml. Gel morphologies with scarcely reported nanostructures including nanofibers, nanobelts, nanodisks, nanotrumpets and nanotubes were firstly observed in bolaamphiphilic self-assembly system.

Poly(benzodithieno-imidazole-alt-carbazole) based π-conjugated copolymers: Highly selective and sensitive turn-off fluorescent probes for Hg2+

In this work, highly emissive and soluble π-conjugated poly(benzodithieno-imidazole-alt-carbazole) π-conjugated copolymers (P1 and P2) have been synthesized through Pd(0)-catalyzed Suzuki coupling polymerization protocol from the corresponding monomers. For solubilizing in common organic solvents, heptyl (in P1) or 2-(2-(2-methoxyethoxy)ethoxy)ethyl (in P2) substituents have been introduced at benzodithieno-imidazole and 9-position of carbazole unit. The well-defined and soluble π-conjugated polymers have been characterized by multinuclear NMR spectra as well as by tetradetector GPC studies showing molecular weight (Mn) of 16.5 and 14.3 kDa with the polydispersity indices of 1.36 and 1.31 respectively. The emissive π-conjugated polymers show remarkable selectivity and sensitivity towards Hg2+ ion as turn-off fluorescent probes as a result of molecular wire effect, without interference by other competing metal ions. The detailed photophysical and sensing studies have been demonstrated to understand the insight of polymer-metal ion interaction which is responsible for selective fluorescence quenching of the π-conjugated polymers. DFT studies have been performed to gain the insight of the electronic properties of the sensor by determining the frontier molecular orbitals and the HOMO-LUMO energy levels for a model probe (M1). The polymeric probes (P1 and P2) are reversible in nature, and can also act as secondary sensors for S2-. The limit of detection of the polymer probes towards Hg2+ is found to be in the range of 40–50 ppb with high association constant in the order of 105 M?1 suggesting its high applicability as chemosensor for Hg2+. The polymers have also been explored as thin film polymeric sensor towards Hg2+ to demonstrate its practical utility.

A new multi-addressable molecular switch based on a photochromic diarylethene with a thieno-imidazole unit

A novel photochromic diarylethene has been synthesized using dithieno-benzo-imidazole as a functional group and perfluorodiarylethene as photon-controlled unit via a benzene linkage. The diarylethene could be used as a multi-addressable fluorescence switch upon triggering by acid/base, light, and Al3+ in acetonitrile. When stimulated by base, the absorption maximum of its closed-ring isomer was red-shifted from 560 nm to 594 nm with an evident color change from purple to blue. When induced by acid, the emission intensity of its open-ring isomer was enhanced by 109 fold with a notable fluorescence color change from dark to bright cyan. Moreover, its fluorescence intensity was dramatically increased when triggered by Al3+ and its emission peak was red-shifted from 460 nm to 476 nm due to the formation of a 1:2 metal/ligand complex. In addition, its light and metal-responsive fluorescence behavior was applied to the construction of a molecular logic circuit with three inputs and one output.

A 2, 1, 3-benzothiadiazole and b thiophene derivatives and its synthetic method

The invention discloses 2,1,3-benzothiadiazoledithiophene derivatives. The derivatives relate to 5,8-dialkylbisthiophene benzothiadiazole. A preparation method includes preparing in sequence 5,5'-dialkyl-3,3'-bithiophene, 2,7-dialkylbenzodithiophene-4,5-diketone, 2,7-dialkylbenzodithiophene-4,5-dione dioxime, 2,7-dialkyl-4,5-dihydrobenzodithiophene-2,5-diamine, adding dropwise SOCl2 into a mixture of the 2,7-dialkyl-4,5-dihydrobenzodithiophene-2,5-diamine, triethylamine and CH2Cl2, and reacting at room temperature to obtain the 5,8-dialkylbisthiophene benzothiadiazole. The derivatives have good plane regularity, heat stability and good environment adaptability. The derivatives are liable to be processed to membrane, and can be used as intermediates in synthesis for organic solar energy battery materials.