18245-28-8Relevant articles and documents
Branched oligothiophene silanes with the efficient nonradiative energy transfer between the fragments
Borshchev,Ponomarenko,Kleymyuk,Luponosov,Surin,Muzafarov
, p. 797 - 805 (2010)
The synthesis of new dendrimers and branched oligothiophene silanes containing bithiophene groups at the periphery and quaterthiophene fragments at the center of the molecule is described. Specific features of bithiophene silane bromination were shown, and the conditions for the efficient synthesis of methyltris(5-bromo-2,2′-bithiophen-5-yl)silane have been found for the first time. The optical properties of the synthesized compounds were studied. The efficiency of the electron excitation energy transfer between the fragments of branched bi-and quaterthiophene silanes was measured.
Synthesis and characterisation of 1,2-difluoro-1,2-bis(5-trimethyl-silyl-2-thienyl)ethenes. A new family of conjugated monomers for oxidative polymerisation
Albertin, Luca,Bertarelli, Chiara,Gallazzi, Maria C.,Meille, Stefano V.,Capelli, Silvia C.
, p. 1752 - 1759 (2002)
The synthesis of a series of (E)-1,2-difluoro-1,2-bis(2-thienyl)ethenes (DFDTEs) by low temperature reaction of 2-lithiothiophenes with tetrafluoroethene (TFE) is described. A possible explanation of the mechanism leading to the formation of higher oligomers is also elucidated together with the use of TMS as protecting group to prevent it. All compounds are thoroughly characterised and their E - configuration proved by vibrational spectroscopy. The crystal structure at 120 K of a representative system evidences its essential planarity and suggests significant delocalisation of π-electrons. Fluorine atoms are involved both in short intra- and intermolecular interactions with sulfur atoms and hydrogen atoms, apparently stabilising the planar molecular arrangement.
Reducing Energy Disorder of Hole Transport Layer by Charge Transfer Complex for High Performance p–i–n Perovskite Solar Cells
Xu, Guiying,Xue, Rongming,Stuard, Samuel J.,Ade, Harald,Zhang, Chenjie,Yao, Jianlin,Li, Yaowen,Li, Yongfang
, (2021)
Solution-processed organic semiconductor charge-transport layers (OS-CTLs) with high mobility, low trap density, and energy level alignment have dominated the important progress in p–i–n planar perovskite solar cells (pero-SCs). Unfortunately, their inevi
Continuous flow synthesis of organic electronic materials-case studies in methodology translation and scale-up
Seyler, Helga,Haid, Stefan,Kwon, Tae-Hyuk,Jones, David J.,Baeuerle, Peter,Holmes, Andrew B.,Wong, Wallace W. H.
, p. 151 - 156 (2013)
The continuous flow synthesis of functional thiophene derivatives was examined. Methodology for the lithiation of thiophene building blocks was developed using a commercial bench-top flow reactor. In addition, the advantages of flow processing were demonstrated in the synthesis of a high performance organic dye in gram scale.
Heptafluoropropylation of Various Substituted Thiophenes with Bis(heptafluorobutyryl) Peroxide. Preparation of 3-Heptafluoropropylthiophen
Yoshida, Masato,Yoshida, Tatsuro,Kamigata, Nobumasa,Kobayashi, Michio
, p. 3549 - 3552 (1988)
The heptafluoropropylations of several substituted thiophenes with bis(heptafluorobutyryl) peroxide were studied.The orientations of the heptafluoropropylation were examined and compared with those of usual electrophilic substitution.The method for the preparation of 3-heptafluoropropylthiophene was also explored.
Tuning the aggregation behaviour of BN-coronene diimides with imide substituents and their performance in devices (OLEDs and OFETs)
Geffroy, Bernard,Hissler, Muriel,Hoffmann, Jonas,Jaques, Emmanuel,Staubitz, Anne
supporting information, p. 14720 - 14729 (2021/11/09)
Compared to perylene diimides (PDIs), coronene diimides (CDIs), which can be viewed as a lateral core extension, show undesired effects for optoelectronic devices such as the decrease of the absorption and a hypsochromic shift. Here, we demonstrate that, if the core is extended with two BN units as opposed to two CC units, the opposite is true: large bathochromic shifts can be achieved, together with higher molar extinction coefficients and beneficial luminescence properties,e.g.small Stokes shifts and high quantum yields (Φlum> 94%). These effects can be explained by the influence of the BN-unit on the frontier molecular orbitals of theBNCDIs. Different substitution motifs at the imide position, cyclohexyl and 2,6-diisopropylphenyl, although they had no influence on the optical properties on a single molecule level, influenced the aggregation substantially so that the optical properties in the solid state and the performance in organic devices (OLEDs and OFETs) differed considerably. In combination with host matrices, devices with EQEs of up to 1.5% and white light emission (0.317; 0.346) were obtained. The developed synthetic route starting from a regioisomeric pure 1,7-substituted PDI leads toBNCDIs in good yields, which makes this class of compounds very promising.
BN-Substituted coronene diimide donor-acceptor-donor triads: photophysical, (spectro)-electrochemical studies and Lewis behavior
Hoffmann, Jonas,Jacquemin, Denis,Hissler, Muriel,Staubitz, Anne
supporting information, p. 13926 - 13934 (2021/10/20)
Boron/nitrogen substituted polyaromatic hydrocarbons (PAHs) are unique materials, with similar molecular structures to their carbon/carbon analogs, but different electronic properties. We report how these may be tuned by substitution at the B and/or N ato
Catalytic B-C Coupling by Si/B Exchange: A Versatile Route to π-Conjugated Organoborane Molecules, Oligomers, and Polymers
Lik, Artur,Fritze, Lars,Müller, Lars,Helten, Holger
supporting information, p. 5692 - 5695 (2017/05/04)
Conjugated organoboranes have emerged as attractive hybrid materials for optoelectronic applications. Herein, a highly efficient, environmentally benign catalytic B-C bond formation method is presented that uses organosilicon compounds, dibromoboranes, and the metal-free organocatalyst Me3SiNTf2. This Si/B exchange approach has been successfully applied to the synthesis of arylborane molecules 4a-c, oligomers 8a,b, and polymers 8a′,b′. Photophysical investigations, supported by TD-DFT calculations, reveal highly effective π-conjugation in thienyl- and furylborane species; the latter are also highly emissive.
Synthesis and characterization of symmetrical sulfur-fused polycyclic aromatic hydrocarbons with controlled shapes
Yin, Jianghui,Hu, Yumiao,Zhang, Dengqing,Li, Xianying,Jin, Wusong
, p. 5794 - 5799 (2017/09/05)
Here we report and establish a facile synthetic method for these unprecedented sulfur-fused polycyclic aromatic hydrocarbons (S-PAHs) with symmetrical structures (C2-rectangle and D6h-hexagonal shape). Characterization by laser desor
Nucleophilic attack of R-lithium at tetrahedral silicon in alkoxysilanes. An alternate mechanism
Furgal, Joseph C.,Laine, Richard M.
, p. 705 - 725 (2016/07/14)
The currently accepted mechanism for nucleophilic attack at silicon in tetraalkoxysilanes, e.g. Si(OEt)4 is suggested to involve formation of penta- and then hexacoordinated intermediates as supported by the apparent exclusive formation of R3SiOR′ and R4Si from nucleophilic attack by RLi and RMgX. Our recent discovery of a direct route from biogenic silica to tetraalkoxyspirosiloxanes prompted us to revisit this reaction as a potential route to diverse silicon-containing species with single SiC bonds as early studies demonstrate that spirosiloxanes form quite stable pentacoordinated alkoxysilane compounds. As anticipated, Si(2-methyl-2,4-pentanediolato)2 (SP) reacts with RLi (R = Ph, anthracene, phenylacetylene, etc.) at -78 °C to form pentacoordinated Si, e.g. LiPhSP equilibrates with the starting reagents even at 3:1 ratios of PhLi:SP with no evidence for formation of hexacoordinated species by mass spectral, NMR and quenching studies. Thus, quenching with MeI or Me3SiCl allows isolation of monosubstituted products from RLi:SP; RSi(OR′)3 including some ring-opened oligomers. Comparative studies of reactions of PhLi with Si(OEt)4 allows isolation of mono- and disubstituted products again even at 1:1 ratios of PhLi:Si(OEt)4. However, on standing at -78 °C for long periods of time or on warming to 0 °C, the primary product for both reactions is Ph4Si even with 0.5 equivalents of PhLi. At reaction temperatures ≥0 °C the primary product is again Ph4Si. These results suggest that hexacoordinated intermediates are not part of the substitution mechanism and may suggest that the higher-substituted compounds arise from disproportionation processes. We also briefly describe the conversion of anthracenylSP and 9,9-dimethylfluoreneSP to silsesquioxanes.
