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Highly Efficient Cooperative Catalysis by CoIII(Porphyrin) Pairs in Interpenetrating Metal–Organic Frameworks 下载免费PDF全文
Zekai Lin Dr. Zhi‐Ming Zhang Dr. Yu‐Sheng Chen Prof. Wenbin Lin 《Angewandte Chemie (International ed. in English)》2016,55(44):13739-13743
A series of porous twofold interpenetrated In‐CoIII(porphyrin) metal–organic frameworks (MOFs) were constructed by in situ metalation of porphyrin bridging ligands and used as efficient cooperative catalysts for the hydration of terminal alkynes. The twofold interpenetrating structure brings adjacent CoIII(porphyrins) in the two networks parallel to each other with a distance of about 8.8 Å, an ideal distance for the simultaneous activation of both substrates in alkyne hydration reactions. As a result, the In‐CoIII(porphyrin) MOFs exhibit much higher (up to 38 times) catalytic activity than either homogeneous catalysts or MOF controls with isolated CoIII(porphyrin) centers, thus highlighting the potential application of MOFs in cooperative catalysis. 相似文献
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Three ZnII metal‐organic frameworks (Zn‐MOFs), [Zn2(tib)(HL1)(H2L1)0.5]?2H2O ( 1 ), [Zn2(tib)(L2)]?H2O ( 2 ) and [Zn3(tib)(L3)2(H2O)6]?2 H2O ( 3 ), have been prepared by reactions of 1,3,5‐tris(1‐imidazolyl)benzene (tib), and biphenyl‐3,3′,4,4′‐tetracarboxylic acid (H4L1), 4,4′‐oxydiphthalic acid (H4L2), or benzene‐1,3,5‐tricarboxylic acid (H3L3) with corresponding ZnII salts, respectively. Single crystal structure analyses reveal that 1 and 2 are constructed by Zn‐centered polyhedra, tib and multidentate tetracarboxylate ligands to form 3‐dimensional frameworks. In contrast, when the tetracarboxylate ligands were replaced by tricarboxylate ligand, layered structure of 3 is produced. These compounds are further characterized by powder X‐ray diffraction, element analyses, thermogravimetric analyses and photoluminescent spectroscopy. The luminescent properties of three Zn‐MOFs dispersed in different solvents have been investigated systematically, demonstrating high sensitivity for the detection of nitro compounds via a fluorescence quenching mechanism. 相似文献
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A Stable Microporous Mixed‐Metal Metal–Organic Framework with Highly Active Cu2+ Sites for Efficient Cross‐Dehydrogenative Coupling Reactions 下载免费PDF全文
Xiu‐Li Yang Chao Zou Dr. Yabing He Min Zhao Prof. Dr. Banglin Chen Prof. Dr. Shengchang Xiang Prof. Dr. Michael O'Keeffe Prof. Dr. Chuan‐De Wu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(5):1447-1452
Two metalloporphyrin octacarboxylates were used to link copper(II) nodes for the formation of two novel porous mixed‐metal metal–organic frameworks (M′MOFs) containing nanopore cages (2.1 nm in diameter) or nanotubular channels (1.5 nm in diameter). The highly active Cu2+ sites on the nanotubular surfaces of the stable porous M′MOF ZJU‐22 , stabilized by three‐connected nets, lead to the superior catalytic activity for the cross‐dehydrogenative coupling (CDC) reaction. 相似文献
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An Ideal Detector Composed of Two‐Dimensional Cd(II)–Triazole Frameworks for Nitro‐Compound Explosives and Potassium Dichromate 下载免费PDF全文
Prof. Dr. Ying Wang Dr. Lin Cheng Zheng‐Yu Liu Xiu‐Guang Wang Bo Ding Long Yin Bing‐Bing Zhou Ming‐Shu Li Jia‐Xuan Wang Prof. Dr. Xiao‐Jun Zhao 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(40):14171-14178
The two‐dimensional (2D) metal–organic framework (MOF) [Cd(TPTZ)(H2O)2(HCOOH)(IPA)2]n ( 1 ; TPTZ={4‐[4‐(1H‐1,2,4‐triazol‐1‐yl)phenyl]phenyl}‐1H‐1,2,4‐triazole, IPA=isophthalic acid) has been constructed with the π‐electron‐rich aromatic ligand TPTZ, auxiliary ligand IPA, and the metal Cd2+ ion with a d10 configuration under solvothermal conditions. Complex 1 exhibits a strong ligand‐originated photoluminescence emission, which is selectively sensitive toward electron‐deficient nitroaromatic compounds, such as nitrobenzene (NB), 1,3‐dinitrobenzene (m‐DNB), and 1,4‐dinitrobenzene (p‐DNB), and nitro‐aliphatic compounds, such as nitromethane (NM) and tris(hydroxymethyl)nitromethane. This property makes complex 1 a potential fluorescence sensor for these chemicals. Single‐crystal X‐ray diffraction studies revealed that dinuclear cadmium building units were further bridged by TPTZ ligands to give a four‐connected uninodal net with the Schläfli symbol of [4.63.4.63.62.64]. 相似文献
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《化学:亚洲杂志》2017,12(6):643-647
A fully conjugated system 4 consisting of two 2‐aza‐21‐carbaporphyrin (NCP) subunits bridged by dipyrrin was synthesized by a highly selective condensation of 3‐pyrrole‐NCP 2 with aryl aldehydes. The free base 4 as well as its silver(III) complex 5 exhibited flexibility of the bridge allowing synergetic binding of AgI, thus leading to a mixed‐valence tetraporphyrinic assembly consisting of eight silver atoms which was characterized both in the solid state and in solution. Binding of chiral acid by 4 and 5 was shown by observation of an induced optical activity of the adducts. 相似文献
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Dr. Huabin Zhang Dr. Mingjian Zhang Prof. Ping Lin Dr. Victor Malgras Dr. Jing Tang Prof. Saad M. Alshehri Prof. Yusuke Yamauchi Prof. Shaowu Du Prof. Jian Zhang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(3):1141-1145
Metal–organic framework (MOF)‐based energetic material [Cu3(MA)2(N3)3] ( 1 ; MA=melamine) was synthesized and structurally characterized (47.55 % N). The structural analysis revealed the existence of unusual multiwalled tubular channels and interweaving of single and double helical units in 1 . The standard molar enthalpy of formation was found to be 1788.73 kJ mol?1, which is the highest value among previously reported MOF‐based energetic materials. The calculated detonation properties showed that 1 can be used as a potential explosive. Sensitivity tests revealed that 1 is insensitive and thus can function as a high‐energy‐density material with a favorable level of safety. 相似文献
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Symmetry‐Guided Synthesis of Highly Porous Metal–Organic Frameworks with Fluorite Topology 下载免费PDF全文
Muwei Zhang Ying‐Pin Chen Mathieu Bosch Thomas Gentle III Kecheng Wang Dawei Feng Dr. Zhiyong U. Wang Prof. Dr. Hong‐Cai Zhou 《Angewandte Chemie (International ed. in English)》2014,53(3):815-818
Two stable, non‐interpenetrated MOFs, PCN‐521 and PCN‐523, were synthesized by a symmetry‐guided strategy. Augmentation of the 4‐connected nodes in the fluorite structure with a rigid tetrahedral ligand and substitution of the 8‐connected nodes by the Zr/Hf clusters yielded MOFs with large octahedral interstitial cavities. They are the first examples of Zr/Hf MOFs with tetrahedral linkers. PCN‐521 has the largest BET surface area (3411 m2 g‐1), pore size (20.5×20.5×37.4 Å) and void volume (78.5%) of MOFs formed from tetrahedral ligands. This work not only demonstrates a successful implementation of rational design of MOFs with desired topology, but also provides a systematic way of constructing non‐interpenetrated MOFs with high porosity. 相似文献
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Singly and Doubly 1,2‐Phenylene‐Inserted Porphyrin Arch‐Tape Dimers: Synthesis and Highly Contorted Structures 下载免费PDF全文
Norihito Fukui Prof. Dr. Atsuhiro Osuka 《Angewandte Chemie (International ed. in English)》2018,57(21):6304-6308
Singly and doubly 1,2‐phenylene‐inserted NiII porphyrin arch‐tape dimers 3 and 9 were synthesized from the corresponding β‐to‐β 1,2‐phenylene‐bridged NiII porphyrin dimers 5 and 11 via Ni0‐mediated reductive cyclization and DDQ/Sc(OTf)3‐promoted oxidative cyclization as key steps, respectively. Owing to the fused eight‐membered ring(s), 3 showed a more contorted structure than those of previously reported arch‐tape dimers 2 a and 2 b possessing a fused seven‐membered ring. Furthermore, 9 displayed much larger molecular contortion. As the molecular contortion increases, the Q band of the absorption spectrum becomes more red‐shifted and the electrochemcial HOMO–LUMO gap becomes smaller, reaching at 1294 nm and 0.77 eV in 9 , respectively. The effect of molecular contortion on the electronic properties was studied by means of DFT calculations. 相似文献
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Synthesis,Water Adsorption,and Proton Conductivity of Solid‐Solution‐Type Metal–Organic Frameworks Al(OH)(bdc‐OH)x(bdc‐NH2)1−x 下载免费PDF全文
Mixed‐ligand metal–organic frameworks Al(bdc‐OH)x(bdc‐NH2)1?x (H2bdc‐NH2=aminoterepthalic acid, H2bdc‐OH=hydroxyterephthalic acid) were synthesized and their water adsorption behavior and proton conductivity were investigated. All obtained compounds were isostructural to MIL‐53 (MIL=Materials of Institut Lavoisier) according to XRD measurements under ambient humidity conditions, and were also found to be single phase across the whole mixing ratio from the XRD measurements under humidified conditions. This result clearly shows that all compounds are a solid‐solution‐type mixture of ligands. MIL‐53‐NH2 adsorbs one water molecule per formula with humidification whereas MIL‐53‐OH adsorbs five water molecules. The mixing ratio of the ligands in Al(OH)(bdc‐OH)x(bdc‐NH2)1?x affected the gate‐opening pressure for water adsorption and total water uptake. Proton conductivity of these compounds largely depends on the adsorbed amount of water, which indicates that the proton conductivity of these compounds depends strongly on the hydrogen‐bond network of the conducting media. 相似文献
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Potassium 4,4′‐Bis(dinitromethyl)‐3,3′‐azofurazanate: A Highly Energetic 3D Metal–Organic Framework as a Promising Primary Explosive 下载免费PDF全文
Dr. Yongxing Tang Dr. Chunlin He Dr. Lauren A. Mitchell Dr. Damon A. Parrish Prof. Dr. Jean'ne M. Shreeve 《Angewandte Chemie (International ed. in English)》2016,55(18):5565-5567
Environmentally acceptable alternatives to toxic lead‐based primary explosives are becoming increasingly important for energetic materials. In this study, potassium 4,4′‐bis(dinitromethyl)‐3,3′‐azofurazanate, comprising two dinitromethyl groups and an azofurazan moiety, was synthesized and isolated as a new energetic 3D metal–organic framework (MOF). Several attractive properties, including a density of 2.039 g cm?3, a decomposition temperature of 229 °C, a detonation velocity of 8138 m s?1, a detonation pressure of 30.1 GPa, an impact sensitivity of 2 J, and friction sensitivity of 20 N make 4 a good candidate as a green primary explosive. 相似文献
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Xiaojing Liu Mariana Kozlowska Timur Okkali Danny Wagner Tomohiro Higashino Gerald Brenner‐Weiß Stefan M. Marschner Zhihua Fu Qiang Zhang Hiroshi Imahori Stefan Brse Wolfgang Wenzel Christof Wll Lars Heinke 《Angewandte Chemie (International ed. in English)》2019,58(28):9590-9595
Photoconductivity is a characteristic property of semi‐conductors. Herein, we present a photo‐conducting crystalline metal–organic framework (MOF) thin film with an on–off photocurrent ratio of two orders of magnitude. These oriented, surface‐mounted MOF thin films (SURMOFs), contain porphyrin in the framework backbone and C60 guests, loaded in the pores using a layer‐by‐layer process. By comparison with results obtained for reference MOF structures and based on DFT calculations, we conclude that donor–acceptor interactions between the porphyrin of the host MOF and the C60 guests give rise to a rapid charge separation. Subsequently, holes and electrons are transported through separate channels formed by porphyrin and by C60, respectively. The ability to tune the properties and energy levels of the porphyrin and fullerene, along with the controlled organization of donor–acceptor pairs in this regular framework offers potential to increase the photoconduction on–off ratio. 相似文献
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Jiawei Wang Dr. Zongbi Bao Prof. Huabin Xing Dr. Baogen Su Dr. Zhiguo Zhang Dr. Qiwei Yang Prof. Yiwen Yang Prof. Qilong Ren Prof. Banglin Chen 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(43):15290-15297
Polymeric resins are practically important adsorbents in a wide variety of applications, but they generally suffer from low surface areas and limited functionalized adsorption sites owing to their closely compacted and tangled polymeric chains. A metal–organic framework (MOF)–polymer composite with enhanced adsorption capacity against the compacted polymeric resins was reported. The strategy to incorporate functionalized oligomer within the cavities of the MOF was demonstrated by the preparation of MIL‐101(Cr) incorporated with N‐methyl‐d ‐glucamine‐based organosiloxane polymer. The resulting MOF composite shows high efficiency for the removal of boric acid from water because of exceptionally high loading of functional groups responsible for the boron adsorption. This material offers promising perspectives for boron removal applications in seawater desalination. 相似文献
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Versatile Tailoring of Paddle‐Wheel ZnII Metal–Organic Frameworks through Single‐Crystal‐to‐Single‐Crystal Transformations 下载免费PDF全文
Tapan K. Pal Dr. Subhadip Neogi Prof. Parimal K. Bharadwaj 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(45):16083-16090
A new tetracarboxylate ligand having short and long arms formed 2D layer ZnII coordination polymer 1 with paddle‐wheel secondary building units under solvothermal conditions. The framework undergoes solvent‐specific single crystal‐to‐single crystal (SC‐SC) transmetalation to produce 1Cu . With a sterically encumbered dipyridyl linker, the same ligand forms non‐interpenetrated, 3D, pillared‐layer ZnII metal–organic framework (MOF) 2 , which takes part in SC‐SC linker‐exchange reactions to produce three daughter frameworks. The parent MOF 2 shows preferential incorporation of the longest linker in competitive linker‐exchange experiments. All the 3D MOFs undergo complete SC‐SC transmetalation with CuII, whereby metal exchange in different solvents and monitoring of X‐ray structures revealed that bulky solvated metal ions lead to ordering of the shortest linker in the framework, which confirms that the solvated metal ions enter through the pores along the linker axis. 相似文献
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Franziska Debatin Arne Thomas Prof. Dr. Alexandra Kelling Niklas Hedin Dr. Zoltan Bacsik Dr. Irena Senkovska Dr. Stefan Kaskel Prof. Dr. Matthias Junginger Holger Müller Uwe Schilde Prof. Dr. Christian Jäger Prof. Dr. Alwin Friedrich Dr. Hans‐Jürgen Holdt Prof. Dr. 《Angewandte Chemie (International ed. in English)》2010,49(7):1258-1262
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Synthesis of Doubly Ethyl‐Bridged Bis(p‐sulfonatocalix[4]arene) and Its Supramolecular Polymerization with Viologen Dimer 下载免费PDF全文
Kun‐Peng Wang Dr. Dong‐Sheng Guo Dr. Hong‐Xia Zhao Prof. Yu Liu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(14):4023-4031
A water‐soluble supramolecular polymer with a high degree of polymerization and viscosity has been constructed based on the strong host–guest interaction between p‐sulfonatocalix[4]arenes (SC4As) and viologen. A homoditopic doubly ethyl‐bridged bis(p‐sulfonatocalix[4]arene) (d‐SC4A) was prepared and its binding behavior towards methyl viologen compared with the singly ethyl‐bridged bis(p‐sulfonatocalix[4]arene) (s‐SC4A) by NMR spectroscopy and isothermal titration calorimetry. By employing a viologen dimer (bisMV4+) as the homoditopic guest, two linear AA/BB‐type supramolecular polymers, d‐SC4A?bisMV4+ and s‐SC4A?bisMV4+, were successfully constructed. Compared with s‐SC4A?bisMV4+, d‐SC4A?bisMV4+ shows much higher solubility and viscosity, and has also been characterized by viscosity, diffusion‐ordered NMR spectroscopy, dynamic light scattering, and atomic force microscopy measurements. Furthermore, the polymer is responsive to electrostimulus as viologen is electroactive, which was studied by cyclic voltammetry. This study represents a proof‐of‐principle as the polymer can potentially be applied as a self‐healing and degradable polymeric material. 相似文献
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Dr. Marco Taddei Daniel Antti Steitz Prof. Dr. Jeroen Anton van Bokhoven Dr. Marco Ranocchiari 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(10):3245-3249
Metal–organic frameworks are having a tremendous impact on novel strategic applications, with prospective employment in industrially relevant processes. The development of such processes is strictly dependent on the ability to generate materials with high yield efficiency and production rate. We report a versatile and highly efficient method for synthesis of metal–organic frameworks in large quantities using continuous flow processing under microwave irradiation. Benchmark materials such as UiO‐66, MIL‐53(Al), and HKUST‐1 were obtained with remarkable mass, space–time yields, and often using stoichiometric amounts of reactants. In the case of UiO‐66 and MIL‐53(Al), we attained unprecedented space–time yields far greater than those reported previously. All of the syntheses were successfully extended to multi‐gram high quality products in a matter of minutes, proving the effectiveness of continuous flow microwave technology for the large scale production of metal–organic frameworks. 相似文献