- A Bulk Dielectric Polymer Film with Intrinsic Ultralow Dielectric Constant and Outstanding Comprehensive Properties
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A bulk dielectric polymer film with an intrinsic ultralow k value of 1.52 at 10 kHz has been successfully synthesized based on a novel polyimide FPTTPI. More importantly, such outstanding dielectric properties remain stable up to 280 °C. The excellent ultralow dielectric properties are mainly because of the larger free volume (subnanoscale), which intrinsically exists in the amorphous region of polymeric materials. Meanwhile, FPTTPI also shows excellent thermal stability and mechanical properties, with a glass-transition temperature (Tg) of 280 °C, 5 wt % loss temperature of 530 °C, and a residual of 63% at 800 °C under N2. It was soluble in common solvents, which made it possible to undergo simple spin-on or efficient, low-cost, and continuous roll-to-roll processes.
- Liu, Yiwu,Qian, Chao,Qu, Lunjun,Wu, Yunan,Zhang, Yi,Wu, Xinhui,Zou, Bing,Chen, Wenxin,Chen, Zhiquan,Chi, Zhenguo,Liu, Siwei,Chen, Xudong,Xu, Jiarui
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- Diamine compound and its preparation method and application
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The invention discloses a novel diamine compound, and a preparation method and an application thereof. The preparation method of the novel functional diamine compound comprises the following steps: a large conjugate structure comprising benzophenone carbonyl group is obtained; the ketone carbonyl group is subjected to a Wittig or Wittig-Horner reaction, such that a large conjugate system with a triphenylethylene/tetraphenylethylene structure and comprising a halogen atom is obtained; the halogen atom is further subjected to a Suzuki reaction or a plurality steps of reactions, such that a monoamine compound comprising a triphenylethylene/tetraphenylethylene large conjugate system is obtained; the monoamine compound is subjected to a reaction with halogenated nitrobenzene, such that a dinitro monomer comprising triphenylamine and the triphenylethylene/tetraphenylethylene large conjugate system is obtained; and the dinitro monomer is reduced into the novel diamine compound, such that the novel functional diamine compound comprising triphenylamine and a triphenylethylene/tetraphenylethylene structure is obtained. The synthesis method provided by the invention is simple. Purification is easy. The method is suitable for industrial productions. The synthesized diamine compound has a significant aggregation-induced emission property, and can be used for synthesizing high-performance and functional polymers such as polyamide, polyimide, polyamideimide, polyesterimide, and the like.
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Paragraph 0071; 0072; 0073
(2017/04/27)
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- Mono- and dinuclear pincer nickel catalyzed activation and transformation of C-Cl, C-N, and C-O bonds
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Condensation of 2-NH2C6H4P(Et)Ph (2) with pyrrole-2-carboxaldehyde generated 2-(C4H4N-2′-CH - N)C6H4P(Et)Ph (3). Treatment of 3 with NaH and followed by (DME)NiX2 (X = Cl, Br) afforded mononuclear pincer nickel complexes [Ni{2-(C4H3N-2′-CH - N)C6H4P(Et)Ph}X] (4a, X = Cl; 4b, X = Br). Reaction of [2-NH2C6H4P(Ph)]2(CH2)n (5a, n = 3; 5b, n = 4) with pyrrole-2-carboxaldehyde or 5-tert-butyl-1H-pyrrole-2-carbaldehyde formed [2-(C4H4N-2′-CH - N)C6H4P(Ph)]2(CH2)n (6a, n = 3; 6b, n = 4) and [2-(5′-tBuC4H3N-2′-CH - N)C6H4P(Ph)]2(CH2)4 (6c). Respective treatment of 6a-c with NaH followed by (DME)NiX2 (X = Cl, Br) gave the dinuclear nickel complexes [Ni{2-(5′-RC4H2N-2′-CH - N)C6H4P(Ph)}X]2(CH2)n (7a, R = H, X = Cl, n = 3; 7b, R = H, X = Cl, n = 4; 7c, R = H, X = Br, n = 4; 7d, R = tBu, X = Cl, n = 4). Catalysis of the complexes for the activation and transformation of C-Cl, C-N, and C-O bonds was evaluated. Complex 7c exhibited excellent catalytic activity in the cross-coupling of aryl chlorides or aryltrimethylammonium iodides with arylzinc reagents as well as of aryl sulfamates with aryl Grignard reagents. The dinuclear nickel complexes 7b-d showed higher catalytic activity than the mononuclear complexes in each type of reaction.
- Yang, Xia,Wang, Zhong-Xia
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p. 5863 - 5873
(2015/01/09)
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- P,N,N-Pincer nickel-catalyzed cross-coupling of aryl fluorides and chlorides
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P,N,N-Pincer nickel complexes [Ni(Cl){N(2-R2PC6H 4)(2′-Me2NC6H4)}] (R = Ph, 3a; R = Pri, 3b; R = Cy, 3c) were synthesized and their catalysis toward the Kumada or Negishi cross-coupling reaction of aryl fluorides and chlorides was evaluated. Complex 3a effectively catalyzes the cross-coupling of (hetero)aryl fluorides with aryl Grignard reagents at room temperature. Complex 3a also catalyzes the cross-coupling of (hetero)aryl chlorides and arylzinc reagents at 80 °C with low catalyst loadings and good functional group compatibility. the Partner Organisations 2014.
- Wu, Dan,Wang, Zhong-Xia
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p. 6414 - 6424
(2014/08/18)
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- Cross-coupling of aryltrimethylammonium iodides with arylzinc reagents catalyzed by amido pincer nickel complexes
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The cross-coupling reaction of aryltrimethylammonium iodides with aryl- or heteroarylzinc chlorides catalyzed by amido pincer nickel complexes was performed. The reaction requires low catalyst loading and displays broad substrate scope.
- Zhang, Xue-Qi,Wang, Zhong-Xia
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experimental part
p. 3658 - 3663
(2012/05/20)
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- Nickel complexes supported by quinoline-based ligands: Synthesis, characterization and catalysis in the cross-coupling of arylzinc reagents and aryl chlorides or aryltrimethylammonium salts
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Lithium and nickel complexes bearing quinoline-based ligands have been synthesized and characterized. Reaction of 8-azidoquinoline with Ph 2PNHR (R = p-MeC6H4, But) affords N-(8-quinolyl)iminophosphoranes RNHP(Ph2)N(8-C9H 6N) (1a, R = p-MeC6H4; 1b, R = But. C9H6N = quinolyl)). Reaction of 1a with (DME)NiCl 2 generates a nickel complex [NiCl2{N(8-C 9H6N)P(Ph2)NH(p-MeC6H4)}] (2a). Treatment of 1b with (DME)NiCl2 and following with NaH produces [NiCl{(1,2-C6H4)P(Ph)(NHBut)N(8-C 9H6N)}] (4). Complex 4 was also obtained by reaction of (DME)NiCl2 with [Li{(1,2-C6H4)P(Ph)(NHBu t)N(8-C9H6N)}] (5) prepared through lithiation of 1b. Reaction of 2-PyCH2P(Ph2)N(8-C9H 6N) (6, Py = pyridyl) and PhNC(Ph)CH2P(Ph 2)N(8-C9H6N) (8), respectively, with (DME)NiCl2 yields two five-coordinate N,N,N-chelate nickel complexes, [NiCl2{2-PyCH2P(Ph2)N(8-C9H 6N)}] (7) and [NiCl2{PhNC(Ph)CH2P(Ph 2)N(8-C9H6N)}] (9). Similar reaction between Ph2PCH2P(Ph2)N(8-C9H6N) (10) and (DME)NiCl2 results in five-coordinate N,N,P-chelate nickel complex [NiCl2{Ph2PCH2P(Ph2)N(8- C9H6N)}] (11). Treatment of [(8-C9H 6N)NP(Ph2)]2CH2 (12) [prepared from (Ph2P)2CH2 and 2 equiv. of 8-azidoquinoline] with LiBun and (DME)NiCl2 successively affords [NiCl{(8-C9H6N)NP(Ph2)}2CH] (13). The new compounds were characterized by 1H, 13C and 31P NMR spectroscopy (for the diamagnetic compounds), IR spectroscopy (for the nickel complexes) and elemental analysis. Complexes 2a, 4, 7, 9, 11 and 13 were also characterized by single-crystal X-ray diffraction techniques. The nickel complexes were evaluated for the catalysis in the cross-coupling reactions of arylzinc reagents with aryl chlorides and aryltrimethylammonium salts. Complex 7 exhibits the highest activity among the complexes in catalyzing the reactions of arylzinc reagents with either aryl chlorides or aryltrimethylammonium bromides.
- Zhang, Qiang,Zhang, Xue-Qi,Wang, Zhong-Xia
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p. 10453 - 10464,12
(2020/08/31)
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- Cross-coupling reactions of aromatic and heteroaromatic silanolates with aromatic and heteroaromatic halides
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The alkali-metal salts (potassium and sodium) of a large number of aryl- and heteroarylsilanols undergo efficient cross-coupling with a wide range of aromatic bromides and chlorides under mild conditions to form polysubstituted biaryls. The critical feature for the success of these coupling reactions and their considerable scope is the use of bis(tri-tert-butylphosphine)palladium. Under the optimized conditions, electron-rich, electron-poor, and sterically hindered arylsilanolates afford cross-coupling products in good yields. Many functional groups are compatible with the coupling conditions such as esters, ketones, acetals, ethers, silyl ethers, and dimethylamino groups. Two particularly challenging substrates, (2-benzofuranyl)dimethylsilanolate and (2,6-dichlorophenyl)dimethylsilanolate prepared as their sodium salts showed excellent activity in the coupling reactions, in the former case also with aromatic chlorides. General methods for the efficient synthesis of a wide range of aromatic silanols are also described.
- Denmark, Scott E.,Smith, Russell C.,Chang, Wen-Tau T.,Muhuhi, Joseck M.
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supporting information; experimental part
p. 3104 - 3118
(2009/08/07)
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- Palladium-indolylphosphine-catalyzed hiyama cross-coupling of aryl mesylates
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(Chemical Equation Presented) Aryl mesylates are found to be applicable as electrophiles in organosilicon-mediated coupling reactions. The catalyst system comprising 2 mol % of Pd(OAc)2 and CM-phos supporting ligand is highly effective in catalyzing Hiyama cross-coupling of various aryl and heteroaryl mesylates. Interesting acid additive effects show that the presence of 0.25-0.50 equiv of acetic acid efficiently suppresses the mesylate decomposition and generally promotes the coupling product yields.
- So, Chau Ming,Lee, Hang Wai,Lau, Chak Po,Kwong, Fuk Yee
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supporting information; experimental part
p. 317 - 320
(2009/07/04)
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- Pd-P(t-Bu)3-catalyzed consecutive cross-coupling of p-phenylenedizinc compound with two different electrophiles leading to unsymmetrically 1,4-disubstituted benzenes
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(Chemical Equation Presented) Pd-P(t-Bu)3 was found to be a chemoselective catalyst for the reaction of p-phenylenedizinc compound with equimolar amounts of carbon electrophiles to afford the single cross-coupling products in good yields, effectively suppressing the formation of double cross-coupling products. The subsequent additions of other electrophiles to the resulting solutions caused the second cross-coupling of the incipient products to take place, achieving a novel and efficient one-pot synthesis of unsymmetrically 1,4-disubstituted benzenes. The origin of the observed high chemoselectivity was speculated.
- Kawamoto, Takahiro,Ejiri, Shogo,Kobayashi, Kana,Odo, Shunsuke,Nishihara, Yasushi,Takagi, Kentaro
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p. 1601 - 1604
(2008/09/17)
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