- Stabilization of the nematic mesophase by a homogeneously dissolved conjugated polymer
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A semi-conjugated iptycene polymer containing a special "crankshaft" backbone leading to superior solubility in a nematic LC medium was synthesized. The incorporation of this polymer in the LC leads to thermodynamic stabilization of the nematic mesophase. This effect is attributed to organizational coupling of the LC molecules to the polymer chains.
- Lohr, Andreas,Swager, Timothy M.
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- Syntheses and Absolute Stereochemistry of Chiral 9,10-Dihydro-9,10-ethanoanthracenes and their Tricarbonylchromium Complexes
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Several chiral mono- and disubstituted 9,10-dihydro-9,10-ethanoanthracenes have been prepared from the corresponding anthracenes.Most of them were separated into enantiomers by chromatography on cellulose triacetate (CTA) and their absolute chiralities established by chiroptical comparison (via their CD spectra) with key compounds of known configuration.From the laevorotatory 1,5-dibromo derivative 16 the dextrorotatory dideuterio hydrocarbon (+)(9S,10S)-20 was obtained.Complexation of 2,6-dimethyl 9,10-dihydro-9,10-ethanoanthracene (+)-25, obtained by enantioselective chromatography on CTA , with Cr(CO)6 afforded two mono tricarbonylchromium complexes as well as the bis-exo,endo-complex (+)-28.Configurational assignments (exo,endo) are based on the absorption patterns of the bridge protons in the 1H NMR spectra. Keywords: (+)-1,5-Dideuterio-9,10-dihydro-9,10-ethanoanthracene; Enantioselective chromatography on CTA; Circular dichroism; Configurational correlation; Tricarbonylchromium complexes.
- Li, Z.,Werner, A.,Schloegl, K.
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- Synthesis and property of new blue emitting materials with bulky side group
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Two emitting compounds, 9,10-bis-[1,1′;3′,1″]terphenyl-5′-yl-1,5-di-o-tolyl-anthracene [TP-DTA-TP] and 9,10-bis-phenyl[1,1′;3′,1′′]triphenyl-5′-yl-1,5-di-o-tolyl-anthracene [TPB-DTA-TPB] based on new twisted core moiety were synthesized through boration, Suzuki reaction, and Sandmeyer reactions. EL performance was improved by varying the chemical structure of the side group. Physical properties such as optical, electrochemical, and electroluminescent properties were investigated. Synthesized compounds were used as an EML in OLED device: ITO / 2-TNATA (60nm) / NPB (15nm)/ TP-DTA-TP or TPB-DTA-TPB (35 nm) / Alq3 (20nm) / LiF (1nm) / Al (200nm). It was found that TPB-DTA-TPB showed higher luminance efficiency and better C.I.E. value than TP-DTA-TP device.
- Kang, Seokwoo,Lee, Hayoon,Kim, Beomjin,Kang, Hyeonmi,Park, Jongwook
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- Alpha-diimine ligand compound, complex and preparation method of polyolefin lubricating oil base oil
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The present invention provides an alpha-diimine ligand compound having a structure represented by a formula (I), and further provides an alpha-diimine complex obtained from the ligand compound. In addition, the invention also provides a preparation method of polyolefin lubricating oil base oil taking the alpha-diimine complex as a catalyst and the prepared lubricant base oil. According to the ligand compound and the complex provided by the invention, a large steric hindrance group is introduced into a ligand skeleton, and the skeleton rigidity is increased, so that the chain walking capabilityof the complex as a catalyst is improved. The polyolefin lubricating oil base oil provided by the invention has high long-chain branch content and branching degree, can be used as medium-high viscosity lubricating oil base oil, simplifies the production process, reduces the production cost, is very suitable for industrial-scale production, and has excellent economic and social benefits.
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Paragraph 0142-0145
(2020/07/24)
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- Modular Approach to the Synthesis of Two-Dimensional Angular Fused Acenes
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Herein, we present a modular approach to pristine angularly fused planar acenes. The approach includes the Pd-catalyzed fusion of several building blocks and implements a dehydrative ?-extension (DPEX) reaction as a key step enabling facile access to diverse two-dimensional acenes. The scope was demonstrated on nine examples with up to quantitative yield.
- Feofanov, Mikhail,Akhmetov, Vladimir,Sharapa, Dmitry I.,Amsharov, Konstantin
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supporting information
p. 1698 - 1702
(2020/01/31)
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