- Ni: Vs. Pd in Suzuki-Miyaura sp2-sp2 cross-coupling: A head-to-head study in a comparable precatalyst/ligand system
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The Suzuki-Miyaura reaction is a cornerstone method for sp2-sp2 cross-coupling in industry. There has been a concerted effort to enable the use of Ni catalysis as an alternative to Pd in order to mitigate cost and improve sustainability. Despite significant advances, ligand development for Ni-catalyzed Suzuki-Miyaura cross-coupling remains underdeveloped when compared to Pd and, as a consequence, ligands for Ni-catalyzed processes are typically taken from the Pd arena. In this study we evaluate the effect of using a similar Ni and Pd precatalyst based on a common bidentate ligand (dppf) in a head-to-head format for the most common type of biaryl couplings, establishing the practical implications of direct replacement of Pd with Ni, and identifying the potential origins of these observations in a mechanistic context.
- West, Matthew J.,Watson, Allan J. B.
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p. 5055 - 5059
(2019/06/03)
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- Synthesis and characterization of quinoxaline derivative as organic semiconductors for organic thin-film transistors
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Three new quinoxaline-based derivatives, end-functionalized with 2,3,5,8-tetraphenyl (3), 2,3-diphenyl-5,8-di(thiophen-2-yl) (4), and 2,3-diphenyl-5,8-bis(5-phenylthiophen-2-yl) (5) were synthesized, characterized, and incorporated as organic semiconducto
- Kim, Hyekyoung,Reddy, M. Rajeshkumar,Hong, Seong-Soo,Kim, Choongik,Seo, Sung Yong
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p. 5530 - 5538
(2017/05/09)
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- Benzothiadiazole-Based Small-Molecule Semiconductors for Organic Thin-Film Transistors and Complementary-like Inverters
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New benzothiadiazole derivatives, 4,7-bis(5-phenylthiophen-2-yl)benzo[c][1,2,5]thiadiazole (PT-BTD) and 4,7-bis[4-(thiophen-2-yl)phenyl]benzo[c][1,2,5]thiadiazole (TP-BTD), were synthesized and characterized as small-molecule organic semiconductors for organic thin-film transistors (OTFTs) and complementary inverters. The thermal, optical, and electrochemical properties of the new compounds were fully characterized. Vacuum-deposition and solution-shearing methods were used to fabricate thin films based on these compounds. Thin films based on PT-BTD exhibited p-channel characteristics with hole mobilities as high as 0.10 cm2 V?1 s?1 and current on/off ratios >107 for top-contact/bottom-gate OTFT devices. With an optimized blending ratio of PT-BTD and the representative n-channel semiconductor N,N′-1H,1H-perfluorobutyl dicyanoperylenediimide, bulk heterojunction ambipolar transistors were fabricated with balanced hole and electron mobilities of 0.10 and 0.07 cm2 V?1 s?1, respectively. Furthermore, a complementary-like inverter was fabricated using ambipolar thin-film transistors, which showed a high voltage gain of 84.
- Kim, Hyekyoung,Reddy, M. Rajeshkumar,Kim, Hyungsug,Choi, Donghee,Kim, Choongik,Seo, SungYong
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p. 742 - 749
(2017/06/06)
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- AROMATIC AMINE DERIVATIVE AND ORGANIC ELECTROLUMINESCENT ELEMENT
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Provided are a long-lifetime organic electroluminescence device which can be fabricated in an improved yield owing to suppressed crystallization of molecules, and an aromatic amine derivative that realizes the device, i.e. , a novel aromatic amine derivative having a specific structure. Specifically provided are an organic electroluminescence device, including an organic thin film layer formed of one or more layers including at least a light emitting layer, the organic thin film layer being interposed between a cathode and an anode, and an aromatic amine derivative for at least one layer of the organic thin film layer, in particular, a hole transporting layer, the derivative having at least one such structure that a substituent in which two or more specific heterocycles are linked to each other, in particular, a substituent in which two or more specific heterocycles are linked through an aryl group is bonded to an amine through an aryl group.
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Page/Page column 28; 38
(2012/01/11)
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- AROMATIC AMINE DERIVATIVE AND ORGANIC ELECTROLUMINESCENT DEVICE USING THE SAME
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Provided are an organic electroluminescent device including an aromatic amine derivative formed of a specific structure having a thiophene structure and an organic thin film layer interposed between a cathode and an anode and formed of one layer or a plurality of layers including at least a light emitting layer, in which at least one layer of the organic thin film contains the aromatic amine derivative alone or as a component of a mixture, the organic electroluminescent device in which molecules hardly crystallize, and which decreases a driving voltage, can be produced with improved yields upon the production of the organic electroluminescent device, and has a long lifetime, and an aromatic amine derivative realizing the organic electroluminescent device.
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Page/Page column 46-47
(2010/05/13)
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- Photochromic dichroic naphtho-pyrans and optical articles containing them
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A naphthopyran compound represented by the formulae (I) to (IV) wherein : ■ m1, m2, p, q are each an integer comprised from 0 to 4 or 5 inclusive; ■ R1, R2 and R4, represent a group selected from halogen, H, -Ra, aryl, -OH, -ORa, -SH, -SRa, -NH2, -NRaRa1, -NRbRc, -NRa1CORa, -NRa1CO(aryl), -NRa1aryl, -N-aryl2, -N(aryl)CO(aryl), -CO-Ra, -CO2Ra1, -OC(O)-Rd, and - X-(Re)-Y, and linear or branched (C1-C18) perfluoroalkyl group, wherein Ra, Ra1, Rb, Rc, X, Y, Re, Rd are as defined into the description; ■ Z1 represent a group selected from: wherein R3, J and n are as defined into the description; ■ R5, Z2, Z3 are as defined into the description; ■ Z4 represent a group selected from: o wherein R3, J and n are as defined hereinbefore; ■ with the provision that for compounds of formula (II) when Z1 represents a group then Z3 is not a hydrogen.
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Page/Page column 18
(2009/09/26)
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- Organic compounds for electroluminescence and organic electroluminescent devices using the same
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Disclosed is a novel group of compounds having a general structure of anthracene body substituted with at least one thiophenyl group, which can be further substituted with various substituent groups. These new compounds are generally compatible with organic electroluminescence. Also disclosed are organic electroluminescent devices and method of making the same. The organic electroluminescent devices include at least one of the compounds in various layers thereof. Organic electroluminescent devices employing the new compounds in their light-emitting layers show outstanding stability.
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Page/Page column 77
(2009/02/11)
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- AROMATIC AMINE DERIVATIVES AND ORGANIC ELECTROLUMINESCENT DEVICE USING SAME
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The present invention provides a novel aromatic amine derivative having a specific structure and an organic electroluminescence device in which an organic thin film layer comprising a single layer or plural layers including at least a light emitting layer is interposed between a cathode and an anode, wherein at least one layer in the above organic thin film layer, particularly a hole injecting layer contains the aromatic amine derivative described above in the form of a single component or a mixed component. Use of the aromatic amine derivative described above materialize an organic electroluminescence device which reduces an operating voltage and makes molecules less liable to be crystallized and which enhances a yield in producing the organic EL device and has a long lifetime.
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Page/Page column 51
(2008/12/04)
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- NEW DIAMINE DERIVATIVES AND ORGANIC ELECTRONIC DEVICE USING THE SAME
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The present invention relates to a new diamine derivative, and an organic electronic device using the same. The diamine derivative according to the present invention can serve as a hole injecting, hole transporting, electron injecting, electron transporting, or light emitting material in an organic electronic device including an organic light emitting device. Particularly, it can serve as a light emitting dopant as used alone, in particular, a blue light emitting dopant. The organic electronic device according to the present invention exhibits excellent characteristics in terms of efficiency, drive voltage, life time, and stability.
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Page/Page column 52
(2008/12/08)
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- NEW ORGANIC COMPOUNDS FOR ELECTROLUMINESCENCE AND ORGANIC ELECTROLUMINESCENT DEVICES USING THE SAME
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Disclosed is a novel group of compounds having a general structure of anthracene body substituted with at least one thiophenyl group, which can be further substituted with various substituent groups. These new compounds are generally compatible with organic electroluminescence. Also disclosed are organic electroluminescent devices and method of making the same. The organic electroluminescent devices include at least one of the compounds in various layers thereof. Organic electroluminescent devices employing the new compounds in their light-emitting layers show outstanding stability.
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Page/Page column 73
(2010/02/07)
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- Optical and redox properties of a series of 3,4-ethylenedioxythiophene oligomers
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The optical and redox properties of a series of 3,4-ethylenedioxythiophene oligomers (EDOTn, n=1-4) and their β,β'-unsubstituted analogues (Tn, n=1-4) are described. Both series are end capped with phenyl groups to prevent irreversible a-coupling reaction
- Apperloo, Joke J.,Bert Groenendaal,Verheyen, Hilde,Jayakannan, Manickam,Janssen, Rene A. J.,Dkhissi, Ahmed,Beljonne, David,Lazzaroni, Roberto,Bredas, Jean-Luc
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p. 2384 - 2396
(2007/10/03)
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- Javelin-, hockey stick-, and boomerang-shaped liquid crystals. Structural variations on p-quinquephenyl
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The ramifications of changing molecular geometry in a series of all-aromatic liquid crystals derived from p-quinquephenyl are reported. Substituting heterocyclic rings such as thiophene, oxadiazole, oxazole, or 1,3-phenylene into the p-quinquephenylene core affects molecular shape changes via the substituent's exocyclic bond angle. In general, we found that introducing nonlinearity into molecules depresses the melting transition temperature. The symmetric (boomerang-shaped) molecules, 2,5-bisbiphenyl-4-yl-1,3,4-oxadiazole, 2,5-bisbiphenyl-4-yl-oxazole, and 1,3-bisbiphenyl-4-yl-benzene, melt into isotropic phases showing small monotropic mesophases. By contrast, the asymmetric (hockey stick-shaped) mesogens, 2-terphenyl-4-yl-5-phenyl thiophene and 2-terphenyl-4-yl-5-phenyl-1,3,4-oxadiazole, exhibit more stable enantiotropic liquid crystalline phases. The hockey stick-shaped mesogens exhibit a smectic phase as well as a nematic phase. High-temperature X-ray determination of the smectic layer spacing gives an unambiguous picture of interdigitated, bilayerlike supramolecular architecture in the smectic phase. There are associated changes in the mesogen's electrostatic profile when a heterocycle is introduced into the quinquiphenylene framework (e.g., conjugation is perturbed). Our findings suggest that steric packing considerations dominate the phase preferences (nematic versus smectic phases). However, electronic considerations (conjugation) appear to control the range of mesomorphism in this new family of nonlinear liquid crystals.
- Dingemans, Theo J.,Murthy, N. Sanjeeva,Samulski, Edward T.
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p. 8845 - 8860
(2007/10/03)
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