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https://read.qxmd.com/read/30816045/triptycene-based-ladder-polymers-with-one-handed-helical-geometry
#1
Tomoyuki Ikai, Takumu Yoshida, Ken-Ichi Shinohara, Tsuyoshi Taniguchi, Yuya Wada, Timothy M Swager
Here we report an efficient synthesis of optically active ladder-type molecules and polymers through intramolecular cyclization of chiral triptycenes containing bis[2-(4-alkoxyphenyl)ethynyl]phenylene units. The electrophile-induced cyclization reactions are directed away from the bridgehead carbon atoms of triptycene by steric factors, thereby producing one-handed twisted ladder units without any detectable byproducts. Moreover, the quantitative and regioselective nature of this intramolecular cyclization allowed us to synthesize optically active ladder polymers with a well-defined one-handed helical geometry, in which homoconjugated dibenzo[a,h]anthracene units are helically arranged along the main chain...
February 28, 2019: Journal of the American Chemical Society
https://read.qxmd.com/read/30702871/metal-organic-architectures-assembled-from-multifunctional-polycarboxylates-hydrothermal-self-assembly-structures-and-catalytic-activity-in-alkane-oxidation
#2
Jinzhong Gu, Min Wen, Yan Cai, Zifa Shi, Aliaksandr S Arol, Marina V Kirillova, Alexander M Kirillov
A three-component aqueous reaction system comprising copper(II) acetate (metal node), poly(carboxylic acid) with a phenylpyridine or biphenyl core (main building block), and 1,10-phenanthroline (crystallization mediator) was investigated under hydrothermal conditions. As a result, four new coordination compounds were self-assembled, namely, {[Cu(μ3 -cpna)(phen)]·H2 O} n (1), {[Cu(μ-Hbtc)(phen)]·H2 O} n (2), {[Cu(μ3 -Hcpic)(phen)]·2H2 O} n (3), and [Cu6 (μ-Hcptc)6 (phen)6 ]·6H2 O (4), where H2 cpna = 5-(2'-carboxylphenyl)nicotinic acid, H3 btc = biphenyl-2,4,4'-tricarboxylic acid, H3 cpic = 4-(5-carboxypyridin-2-yl)isophthalic acid, H3 cptc = 2-(4-carboxypyridin-3-yl)terephthalic acid, and phen = 1,10-phenanthroline...
January 31, 2019: Inorganic Chemistry
https://read.qxmd.com/read/30614678/unusual-capacity-increases-with-cycling-for-ladder-type-microporous-polymers
#3
Tyler B Schon, So Young An, Andrew J Tilley, Dwight S Seferos
Microporous polymers using triptycene vertices and various ladder-type benzimidazole linkers are synthesized and tested as lithium-ion battery anodes. An unusual increase in performance is observed upon cycling, affording high capacities of 783 and 737 mAh g-1 for a perylene derivative and the pyromellitic derivative after 1000 cycles. The high performance of these materials after cycling is attributed to favorable electrode morphology and high crystallinity for perylene derivative, and the presence of charge carriers for pyromellitic derivative...
January 7, 2019: ACS Applied Materials & Interfaces
https://read.qxmd.com/read/30585714/controlling-molecular-packing-and-orientation-via-constructing-a-ladder-type-electron-acceptor-with-asymmetric-substituents-for-thick-film-non-fullerene-solar-cells
#4
Shiyu Feng, Cai'e Zhang, Zhaozhao Bi, Yahui Liu, Pengcheng Jiang, Shouli Ming, Xinjun Xu, Wei Ma, Zhishan Bo
A non-fullerene acceptor, IDTT-OB, employing indacenodithieno[3,2-b]thiophene as the core with asymmetric side chains, is designed and synthesized. In comparison with the analogue IDT-OB, extending the five-heterocyclic indacenodithiophene core to seven-heterocyclic fused ring endows IDTT-OB with more broad absorption and elevated HOMO energy level. In addition, IDTT-OB shows a more intense molecular packing and a higher crystallinity with a strong face-on orientation in neat film and the PBDB-T:IDTT-OB blend film...
December 26, 2018: ACS Applied Materials & Interfaces
https://read.qxmd.com/read/30566346/structure-directing-effects-of-counterions-in-uranyl-ion-complexes-with-long-chain-aliphatic-%C3%AE-%C3%AF-dicarboxylates-1d-to-polycatenated-3d-species
#5
Pierre Thuéry, Youssef Atoini, Jack Harrowfield
Nine uranyl ion complexes were synthesized under (solvo-)hydrothermal conditions using α,ω-dicarboxylic acids HOOC-(CH2 ) n-2 -COOH (H2 C n, n = 6-9) and diverse counterions. Complexes [PPh4 ][UO2 (C6)(NO3 )] (1) and [PPh4 ][UO2 (C8)(NO3 )] (2) contain zigzag one-dimensional (1D) chains, with further polymerization being prevented by the terminal nitrate ligands. [PPh3 Me][UO2 (C7)(HC7)] (3) crystallizes as a 1D polymer with a curved section, with hydrogen bonding of the uncomplexed carboxylic groups giving rise to formation of 3-fold interpenetrated two-dimensional (2D) networks...
December 19, 2018: Inorganic Chemistry
https://read.qxmd.com/read/30542565/designing-an-asymmetrical-isomer-to-promote-the-lumo-energy-level-and-molecular-packing-of-a-non-fullerene-acceptor-for-polymer-solar-cells-with-12-6-efficiency
#6
Wei Gao, Qiaoshi An, Cheng Zhong, Zhenghui Luo, Ruijie Ming, Miao Zhang, Yang Zou, Feng Liu, Fujun Zhang, Chuluo Yang
Isomers with small structural changes usually exhibit different properties. Rationally designing isomers of some high-performance SMAs can further enhance their function. In this work, an asymmetrical small molecule acceptor (SMA) MeIC1 isomerized from MeIC is reported. Compared with the symmetrical MeIC, the asymmetrical isomer showed almost the same absorption range but an elevated LUMO energy level and simultaneously enhanced π-π stacking and electron mobility by replacing the thieno[3,2- b ]thiophene unit with a larger sized dithieno[3,2- b :2',3'- d ]thiophene unit in the ladder-type core of MeIC...
November 14, 2018: Chemical Science
https://read.qxmd.com/read/30536561/ladder-type-nonacyclic-arene-bis-thieno-3-2-b-thieno-cyclopentafluorene-as-a-promising-building-block-for-non-fullerene-acceptor
#7
Qichun Zhang, Xiaobing Fan, Jianhong Gao, Wei Wang, Shengqiang Xiao, Chun Zhan, Xinhui Lu
A ladder-type nonacyclic arene (bis(thieno[3,2-b]thieno)cyclopentafluorene (BTTF)) has been designed and synthesized through fusing thienothiophenes with the fluorene core from the synthon of dimethyl 9,9-dioctyl-2,7-bis(thieno[3,2-b]thiophen-2-yl)fluorene-3,6-dicarboxylate. With BTTF as the central donor unit, a novel acceptor-donor-acceptor (A-D-A) type non-fullerene small molecule acceptor (BTTFIC) was prepared with 1,1-dicyanomethylene-3-indanones (IC) as the peripheral acceptor units. The energy level of the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) of BTTFIC locate at -5...
December 10, 2018: Chemistry, An Asian Journal
https://read.qxmd.com/read/30523693/si-bridged-ladder-type-small-molecules-acceptors-for-high-performance-organic-photovoltaics
#8
Chun-Kai Wang, Bing-Huang Jiang, Yu-Wei Su, Ru-Jong Jeng, Yu-Jian Wang, ChihPing Chen, Ken-Tsung Wong
In this study, we synthesized 5,11-dihexyl-4,4,10,10-tetraoctylbenzo[1,2-b:4,5-b']bisthieno[4´´,5´´-b´´:4´´´,5´´´-b´´´]silolo[2´´,3´´-d:2´´´,3´´´-d´]thiophene (ArSi) as a ladder-type electron-rich core for the preparation of three A-D-A-type nonfullerene acceptors (NFAs)-ArSiID, ArSiID-F, and ArSiID-Cl-featuring (3-oxo-2,3-dihydro-1H-inden-1-ylidene)malononitrile (ID), 2-(5,6-difluoro-3-oxo-2,3-dihydro-1H-inden-1-ylidene)malononitrile (ID-F), and 2-(5,6-dichloro-3-oxo-2,3-dihydro-1H-inden-1-ylidene)malononitrile (ID-Cl) as peripheral electron-poor units, respectively...
December 7, 2018: ACS Applied Materials & Interfaces
https://read.qxmd.com/read/30506965/towards-unveiling-the-exact-molecular-structure-of-amorphous-red-phosphorus-by-single-molecule-studies
#9
Shuxun Cui, Song Zhang, Hu-Jun Qian, Zhong-Yuan Lu, Zhonghua Liu, Haiming Zhang, Lifeng Chi, Hongyu Ju
Since the discovery of amorphous red phosphorus (a-red P) in 1847, a number of possible structures of a-red P have been proposed. However, the exact molecular structure of a-red P is not determined yet due to the amorphous nature. Here in this study, we utilize several methods to investigate some basic properties of a-red P, which are helpful to determine the structure. The experimental results from scanning tunneling microscopy (STM) and gel permeation chromatography (GPC) confirm that a-red P is a linear inorganic polymer with a broad molecular weight distribution...
December 2, 2018: Angewandte Chemie
https://read.qxmd.com/read/30282946/fatigue-performance-of-rc-beams-strengthened-with-cfrp-under-overloads-with-a-ladder-spectrum
#10
Zhan-Biao Chen, Pei-Yan Huang, Zheng-Wei Li, Xin-Yan Guo, Chen Zhao, Xiao-Hong Zheng, Yi Yang
Vehicle overload is detrimental to bridges and traffic safety. This paper presents a study on the fatigue performance of typical reinforced concrete (RC) beams of highway bridges under vehicle overload. A definition method of vehicle overload and a construction method of overload ladder spectrum were first proposed based on traffic data acquisition, statistical analysis and structural calculation of the highway bridges in Guangzhou. A fatigue experimental method was also proposed with the three-ladder vehicle overload spectrum, and the fatigue tests of 15 RC beams strengthened with carbon fiber reinforced polymer (CFRP) under three loading levels were then carried out...
October 3, 2018: Sensors
https://read.qxmd.com/read/30247790/scope-and-limitations-of-the-dehydrogenative-generation-of-graphenic-nanoribbons-from-methylene-bridged-aromatic-ladder-polymers
#11
Marie-Claire Ockfen, Michael Forster, Ullrich Scherf
A synthetic route to solubilized graphenic nanoribbons (GNRs) by oxidation of methylene-bridged, aromatic ladder polymers is presented. Hereby, the ladder polymer precursors are finally 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (or DDQ) oxidized into the desired GNRs. However, a detailed UV-vis analysis shows already partial oxidation/dehydrogenation during aqueous work-up under loss of ≈50% of the bridgehead hydrogens as well as some indications for overoxidation with DDQ under formation of quinoid carbonyl defects, additionally driven by a reduction of the number of quinoid (quinodimethane) structural units...
September 24, 2018: Macromolecular Rapid Communications
https://read.qxmd.com/read/30177780/dynamic-self-correcting-nucleophilic-aromatic-substitution
#12
Wen Jie Ong, Timothy M Swager
Dynamic covalent chemistry, with its ability to correct synthetic dead-ends, allows for the synthesis of elaborate extended network materials in high yields. However, the limited number of reactions amenable to dynamic covalent chemistry necessarily confines the scope and functionality of materials synthesized. Here, we explore the dynamic and self-correcting nature of nucleophilic aromatic substitution (SN Ar), using ortho-aryldithiols and ortho-aryldifluorides that condense to produce redox-active thianthrene units...
October 2018: Nature Chemistry
https://read.qxmd.com/read/30073729/highly-luminescent-ladderized-fluorene-copolymers-based-on-b-n-lewis-pair-functionalization
#13
Abdullah F Alahmadi, Roger A Lalancette, Frieder Jäkle
A new B-N functionalized polyaromatic building block for conjugated hybrid polymers is developed. Bromine-functionalized dipyridylfluorene is first subjected to Lewis-base-directed electrophilic borylation and subsequently incorporated into conjugated polymers via transition-metal-catalyzed cross-coupling reactions. The borane monomer exhibits bright blue luminescence in solution, as a result of the rigid ladder-type structure generated upon electrophilic borylation. Yamamoto coupling gives rise to a homopolymer and Stille coupling to a vinylene-bridged copolymer...
August 3, 2018: Macromolecular Rapid Communications
https://read.qxmd.com/read/30009536/dna-ladders-can-be-used-to-size-polyphosphate-resolved-by-polyacrylamide-gel-electrophoresis
#14
Stephanie A Smith, Yan Wang, James H Morrissey
PAGE is often used to resolve inorganic polyphosphates (polyP), but unfortunately polyP size ladders are not commercially available. Since several dyes that are commonly used to detect nucleic acids in gels also stain polyP, we examined the utility of commercially available DNA size ladders for estimating polyP polymer lengths by gel electrophoresis. Narrow size fractions of polyP were prepared and their polymer lengths were quantified using NMR. Commercially available DNA ladders and these polyP fractions were then subjected to PAGE to determine the relationship between migration of DNA vs polyP, which was found to be: log10 (dsDNA length in bp) = 1...
October 2018: Electrophoresis
https://read.qxmd.com/read/29984526/single-crystal-to-single-crystal-scsc-linear-polymerization-of-a-desymmetrized-anthraphane
#15
Marco Servalli, Nils Trapp, A Dieter Schlüter
In this work we present one of the rare cases of single-crystal-to-single-crystal (SCSC) linear polymerizations, resulting in a novel ladder-type polymer. The polymerization is based on the photoinduced [4+4]-cycloaddition reactions between trifunctional anthracene-based monomers. The careful design of the monomer anthraphane-tri(OMe), results in perfectly stacked anthracene pairs in the crystal structure, with Schmidt's distances d=3.505-3.666 Å and shift s=1.109 Å, allowing a selective linear polymerization in quantitative yields and in a matter of minutes, without compromising the integrity of the single crystals...
October 9, 2018: Chemistry: a European Journal
https://read.qxmd.com/read/29952564/photochemical-structural-transformation-of-a-linear-1d-coordination-polymer-impacts-the-electrical-conductivity
#16
Basudeb Dutta, Arka Dey, Chittaranjan Sinha, Partha Pratim Ray, Mohammad Hedayetullah Mir
A pair of 4-(1-naphthylvinyl)pyridine (4-nvp) ligands has been successfully aligned in head-to-tail fashion in a one-dimensional (1D) double chain ladder polymer [Cd(adc)(4-nvp)2 (H2 O)] n (1; H2 adc = acetylenedicarboxylic acid) that undergoes a photochemical [2 + 2] cycloaddition reaction accompanied by single-crystal to single-crystal (SCSC) structural transformation from a 1D chain to a 2D layer structure. These structural changes have a significant impact on the conductivity and Schottky nature of the compound...
July 16, 2018: Inorganic Chemistry
https://read.qxmd.com/read/29911315/ladder-type-heteroarene-based-organic-semiconductors
#17
REVIEW
Jianhua Chen, Kun Yang, Xin Zhou, Xugang Guo
The fusion of heteroaromatic rings into ladder-type heteroarenes can stabilize frontier molecular orbitals and lead to improved physicochemical properties that are beneficial for applications in various optoelectronic devices. Thus, ladder-type heteroarenes, which feature highly planar backbones and well-delocalized π conjugation, have recently emerged as a promising type of organic semiconductor with excellent device performance in organic photovoltaics (OPVs) and organic field-effect transistors (OFETs)...
September 17, 2018: Chemistry, An Asian Journal
https://read.qxmd.com/read/29845148/syntheses-crystal-structures-adsorption-properties-and-visible-photocatalytic-activities-of-highly-stable-pb-based-coordination-polymers-constructed-by-2-2-carboxyphenyl-imidazo-4-5-f-1-10-phenanthroline-and-bridging-linkers
#18
Zhi-Min Li, Yu Qiao, Chun-Bo Liu, Yan-Feng Zhou, Xiu-Yan Wang, Paul A Charpentier, Guang-Bo Che, William Z Xu, Li-Hui Liu, En-Wei Zhu
Five highly stable coordination polymers assembled by 2-(2-carboxyphenyl)imidazo(4,5-f)-(1,10)phenanthroline (2-HNCP) and different aromatic carboxylic acid ligands, namely, [Pb(2-NCP)(L1)]n (1), [Pb2(2-NCP)2(L2)]n·2nH2O (2), [Pb2(2-NCP)2(L2)]n (3), [Pb(2-NCP)(L3)0.5]n (4) and [Pb2(2-NCP)2(L4)]n (5), where HL1 = pyridine-4-carboxylic acid, H2L2 = 2-amino-1,4-benzenedicarboxylic acid, H2L3 = 1,4-benzenedicarboxylic acid and H2L4 = 2-hydroxy-1,4-benzenedicarboxylic acid, have been synthesized under hydrothermal conditions...
June 12, 2018: Dalton Transactions: An International Journal of Inorganic Chemistry
https://read.qxmd.com/read/29843471/the-selectivity-of-polymers-imprinted-with-amines
#19
Zsanett Dorkó, Anett Nagy-Szakolczai, Blanka Tóth, George Horvai
One of the main reasons for making molecularly imprinted polymers (MIPs) has been that MIPs interact selectively with a specific target compound. This claim is investigated here with the example of a widely used type of noncovalent MIP, the MIP for the beta blocker propranolol. Adsorption isotherms of this MIP and of a nonimprinted control polymer (NIP), respectively, have been measured with a series of compounds in the porogen solvent acetonitrile. The results, visualized as "selectivity ladders", show that the MIP binds propranolol and many other amines better than the NIP does, but the selectivity of the MIP is actually inferior to that of the NIP...
May 29, 2018: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
https://read.qxmd.com/read/29766573/asymmetrical-ladder-type-donor-induced-polar-small-molecule-acceptor-to-promote-fill-factors-approaching-77-for-high-performance-nonfullerene-polymer-solar-cells
#20
Wei Gao, Miao Zhang, Tao Liu, Ruijie Ming, Qiaoshi An, Kailong Wu, Dongjun Xie, Zhenghui Luo, Cheng Zhong, Feng Liu, Fujun Zhang, He Yan, Chuluo Yang
In this work, an effectual strategy of constructing polar small molecule acceptors (SMAs) to promote fill factor (FF) of nonfullerene polymer solar cells (PSCs) is first reported. Three asymmetrical SMAs of IDT6CN, IDT6CN-Th, and IDT6CN-M, which own large dipole moments, are designed and synthesized. The PSCs based on three polar SMAs exhibit apparently higher FFs compared with their symmetrical analogues. The asymmetrical design strategy accompanied with side chain and end group engineering makes IDT6CN-Th- and IDT6CN-M-based nonfullerene PSCs achieve high power conversion efficiency with FFs approaching 77%...
June 2018: Advanced Materials
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