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Multicomponent Self‐Assembly with a Shape‐Persistent N‐Heterotriangulene Macrocycle on Au(111) 下载免费PDF全文
Kang Cui Dr. Florian Schlütter Dr. Oleksandr Ivasenko Dr. Milan Kivala Dr. Matthias G. Schwab Dr. Shern‐Long Lee Dr. Stijn F. L. Mertens Dr. Kazukuni Tahara Prof. Yoshito Tobe Prof. Klaus Müllen Dr. Kunal S. Mali Prof. Steven De Feyter 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(4):1652-1659
Multicomponent network formation by using a shape‐persistent macrocycle ( MC6 ) at the interface between an organic liquid and Au(111) surface is demonstrated. MC6 serves as a versatile building block that can be coadsorbed with a variety of organic molecules based on different types of noncovalent interactions at the liquid–solid interface. Scanning tunneling microscopy (STM) reveals the formation of crystalline bicomponent networks upon codeposition of MC6 with aromatic molecules, such as fullerene (C60) and coronene. Tetracyanoquinodimethane, on the other hand, was found to induce disorder into the MC6 networks by adsorbing on the rim of the macrocycle. Immobilization of MC6 itself was studied in two different noncovalently assembled host networks. MC6 assumed a rather passive role as a guest and simply occupied the host cavities in one network, whereas it induced a structural transition in the other. Finally, the central cavity of MC6 was used to capture C60 in a complex three‐component system. Precise immobilization of organic molecules at discrete locations within multicomponent networks, as demonstrated here, constitutes an important step towards bottom‐up fabrication of functional surface‐based nanostructures. 相似文献
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Colm Browne Dr. Tanya K. Ronson Prof. Jonathan R. Nitschke 《Angewandte Chemie (International ed. in English)》2014,53(40):10701-10705
The reaction of 2,6‐diformylpyridine with diverse amines and PdII ions gave rise to a variety of metallosupramolecular species, in which the PdII ion is observed to template a tridentate bis(imino)pyridine ligand. These species included a mononuclear complex as well as [2+2] and [3+3] macrocycles. The addition of pyridine‐containing macrocyclic capping ligands allows for topological complexity to arise, thereby enabling the straightforward preparation of structures that include a [2]catenane, a [2]rotaxane, and a doubly threaded [3]rotaxane. 相似文献
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《Chemistry (Weinheim an der Bergstrasse, Germany)》2005,11(1):298-307
The self‐assembly and characterization of water‐soluble calix[4]arene‐based molecular capsules ( 1?2 ) is reported. The assemblies are the result of ionic interactions between negatively charged calix[4]arenes 1 a and 1 b , functionalized at the upper rim with amino acid moieties, and a positively charged tetraamidiniumcalix[4]arene 2 . The formation of the molecular capsules is studied by 1H NMR spectroscopy, ESI mass spectrometry (ESI‐MS), and isothermal titration calorimetry (ITC). A molecular docking protocol was used to identify potential guest molecules for the self‐assembled capsule 1 a?2 . Experimental guest encapsulation studies indicate that capsule 1 a?2 is an effective host for both charged (N‐methylquinuclidinium cation) and neutral molecules (6‐amino‐2‐methylquinoline) in water. 相似文献
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Dr. Sven O. Krabbenborg Janneke Veerbeek Prof. Dr. Jurriaan Huskens 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(27):9638-9644
Self‐assembly to create molecular and nanostructures is typically performed at the thermodynamic minimum. To achieve dynamic functionalities, such as adaptability, internal feedback, and self‐replication, there is a growing focus on out‐of‐equilibrium systems. This report presents the dynamic self‐assembly of an artificial host–guest system at an interface, under control by a dissipative electrochemical process using (electrical) energy, resulting in an out‐of‐equilibrium system exhibiting a supramolecular surface gradient. The gradient, its steepness, rate of formation, and complex surface composition after backfilling, as well as the surface compositions after switching between the different states of the system, are assessed and supported by modelling. Our method shows for the first time an artificial surface‐confined out‐of‐equilibrium system. The electrochemical process parameters provide not only control over the system in time, but also in space. 相似文献
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Arun Kumar Bar Dr. Srinivasarao Raghothama Dr. Dohyun Moon Prof. Partha Sarathi Mukherjee 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(11):3199-3209
Template‐assisted formation of multicomponent Pd6 coordination prisms and formation of their self‐templated triply interlocked Pd12 analogues in the absence of an external template have been established in a single step through Pd? N/Pd? O coordination. Treatment of cis‐[Pd(en)(NO3)2] with K3tma and linear pillar 4,4′‐bpy (en=ethylenediamine, H3tma=benzene‐1,3,5‐tricarboxylic acid, 4,4′‐bpy=4,4′‐bipyridine) gave intercalated coordination cage [{Pd(en)}6(bpy)3(tma)2]2[NO3]12 ( 1 ) exclusively, whereas the same reaction in the presence of H3tma as an aromatic guest gave a H3tma‐encapsulating non‐interlocked discrete Pd6 molecular prism [{Pd(en)}6(bpy)3(tma)2(H3tma)2][NO3]6 ( 2 ). Though the same reaction using cis‐[Pd(NO3)2(pn)] (pn=propane‐1,2‐diamine) instead of cis‐[Pd(en)(NO3)2] gave triply interlocked coordination cage [{Pd(pn)}6(bpy)3(tma)2]2[NO3]12 ( 3 ) along with non‐interlocked Pd6 analogue [{Pd(pn)}6(bpy)3(tma)2](NO3)6 ( 3′ ), and the presence of H3tma as a guest gave H3tma‐encapsulating molecular prism [{Pd(pn)}6(bpy)3(tma)2(H3tma)2][NO3]6 ( 4 ) exclusively. In solution, the amount of 3′ decreases as the temperature is decreased, and in the solid state 3 is the sole product. Notably, an analogous reaction using the relatively short pillar pz (pz=pyrazine) instead of 4,4′‐bpy gave triply interlocked coordination cage [{Pd(pn)}6(pz)3(tma)2]2[NO3]12 ( 5 ) as the single product. Interestingly, the same reaction using slightly more bulky cis‐[Pd(NO3)2(tmen)] (tmen=N,N,N′,N′‐tetramethylethylene diamine) instead of cis‐[Pd(NO3)2(pn)] gave non‐interlocked [{Pd(tmen)}6(pz)3(tma)2][NO3]6 ( 6 ) exclusively. Complexes 1 , 3 , and 5 represent the first examples of template‐free triply interlocked molecular prisms obtained through multicomponent self‐assembly. Formation of the complexes was supported by IR and multinuclear NMR (1H and 13C) spectroscopy. Formation of guest‐encapsulating complexes ( 2 and 4 ) was confirmed by 2D DOSY and ROESY NMR spectroscopic analyses, whereas for complexes 1 , 3 , 5 , and 6 single‐crystal X‐ray diffraction techniques unambiguously confirmed their formation. The gross geometries of H3tma‐encapsulating complexes 2 and 4 were obtained by universal force field (UFF) simulations. 相似文献
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Allyl‐Functionalized Dioxynaphthalene[38]Crown‐10 Macrocycles: Synthesis,Self‐Assembly,and Thiol‐ene Functionalization 下载免费PDF全文
Umesh Choudhary Prof. Brian H. Northrop 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(4):999-1009
Five dioxynaphthalene[38]‐crown‐10 ( DNP38C10 ) macrocycles bearing one, two, three, or four allyl moieties have been synthesized and their ability to spontaneously self‐assemble with methyl viologen to form [2]pseudorotaxanes has been evaluated. Association constants between methyl viologen and several of the allyl‐functionalized DNP38C10 macrocycles are found to be comparable to that of methyl viologen and unfunctionalized DNP38C10 , however, the enthalpic and entropic factors that underlie overall binding free energy vary systematically with increasing allyl substitution. These variations are explained through a combination of solution phase and solid‐state analysis of the macrocycles and their complexes. The utility of endowing DNP38C10 macrocycles with allyl moieties is further demonstrated by the ease with which they can be functionalized through thiol‐ene click chemistry. 相似文献
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Takumi Yamaguchi Shohei Tashiro Dr. Masahide Tominaga Dr. Masaki Kawano Dr. Tomoji Ozeki Dr. Makoto Fujita Prof. Dr. 《化学:亚洲杂志》2007,2(4):468-476
Upon complexation with PdII ions, precisely designed strandlike ligands with two tris(3,5‐pyridine) units at both terminals were assembled, with the aid of a linear template molecule, into a discrete tubular complex with a length of 3.5 nm. The high stability and the well‐defined structure of the coordination nanotube were revealed by NMR spectroscopy, cold‐spray ionization MS, and single‐crystal X‐ray analysis. Guest lengths were discriminated by the tube: When the association of strandlike guest molecules, in which two biphenylene units are linked with an (OCH2CH2)n linker, were compared, the tube selectively recognized an appropriate guest whose length was comparable to that of the tube. Tetrathiafulvalene (TTF)‐terminated linear guests were directly oxidized to TTF2+ in the tube, but reduced stepwise via TTF+? outside the tube. 相似文献
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Kui Wang Dr. Dong‐Sheng Guo Prof. Dr. Yu Liu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(28):8758-8764
The complexation‐induced critical aggregation concentrations of 1‐pyrenemethylaminium by mono‐p‐sulfonatocalix[n]arenes and bis‐p‐sulfonatocalix[n]arenes (n=4, 5) were systemically measured by fluorescence spectroscopy. In all cases, the complexation‐induced critical aggregation concentration decreases by about 3 times upon addition of p‐sulfonatocalix[n]arenes. However, the optimal molar ratios for the aggregation of 1‐pyrenemethylaminium by mono‐p‐sulfonatocalix[n]arenes and bis‐p‐sulfonatocalix[n]arenes are distinctly different: For mono‐p‐sulfonatocalix[n]arenes, the optimum mixing ratio for the aggregation of 1‐pyrenemethylaminium is 1:4 mono‐p‐sulfonatocalix[n]arenes/1‐pyrenemethylaminium, whereas only 2.5 molecules of 1‐pyrenemethylaminium can be bound by one cavity of bis‐p‐sulfonatocalix[n]arenes. The intermolecular complexation of mono‐p‐sulfonatocalix[n]arenes and bis‐p‐sulfonatocalix[n]arenes with 1‐pyrenemethylaminium led to the formation of two distinctly different nanoarchitectures, which were shown to be nanoscale vesicle and rod aggregates, respectively, by using dynamic laser scattering, TEM, and SEM. This behavior is also different from the fiber‐like aggregates with lengths of several micrometers that were formed by 1‐pyrenemethylaminium itself above its critical aggregation concentration. Furthermore, the obtained nanoaggregates exhibit benign water solubility, self‐labeled fluorescence, and, more importantly, temperature responsiveness. 相似文献
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Jia Liu Xu Zhang Prof. Dr. Dong Wang Dr. Jie‐Yu Wang Prof. Dr. Jian Pei Prof. Peter J. Stang Prof. Dr. Li‐Jun Wan 《化学:亚洲杂志》2011,6(9):2426-2430
Over the past few years, two‐dimensional (2D) nanoporous networks have attracted great interest as templates for the precise localization and confinement of guest building blocks, such as functional molecules or clusters on the solid surfaces. Herein, a series of two‐component molecular networks with a 3‐fold symmetry are constructed on graphite using a truxenone derivative and trimesic acid homologues with carboxylic‐acid‐terminated alkyl chains. The hydrogen‐bonding partner‐recognition‐induced 2D crystallization of alkyl chains makes the flexible alkyl chains act as rigid spacers in the networks to continuously tune the pore size with an accuracy of one carbon atom per step. The two‐component networks were found to accommodate and regulate the distribution and aggregation of guest molecules, such as COR and CuPc. This procedure provides a new pathway for the design and fabrication of molecular nanostructures on solid surfaces. 相似文献
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Hai‐tao Zhang Prof. Dr. Xiao‐dong Fan Prof. Dr. Wei Tian Rong‐tian Suo Zhen Yang Yang Bai Wan‐bin Zhang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(13):5000-5008
The controlled secondary self‐assembly of amphiphilic molecules in solution is theoretically and practically significant in amphiphilic molecular applications. An amphiphilic β‐cyclodextrin (β‐CD) dimer, namely LA‐(CD)2, has been synthesized, wherein one lithocholic acid (LA) unit is hydrophobic and two β‐CD units are hydrophilic. In an aqueous solution at room temperature, LA‐(CD)2 self‐assembles into spherical micelles without ultrasonication. The primary micelles dissociates and then secondarily form self‐assemblies with branched structures under ultrasonication. The branched aggregates revert to primary micelles at high temperature. The ultrasound‐driven secondary self‐assembly is confirmed by transmission electron microscopy, dynamic light scattering, 1H NMR spectroscopy, and Cu2+‐responsive experiments. Furthermore, 2D NOESY NMR and UV/Vis spectroscopy results indicate that the formation of the primary micelles is driven by hydrophilic–hydrophobic interactions, whereas host–guest interactions promote the formation of the secondary assemblies. Additionally, ultrasonication is shown to be able to effectively destroy the primary hydrophilic–hydrophobic balances while enhancing the host–guest interaction between the LA and β‐CD moieties at room temperature. 相似文献
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Periodic Mesoporous Organosilica with Molecular‐Scale Ordering Self‐Assembled by Hydrogen Bonds 下载免费PDF全文
Dr. Norihiro Mizoshita Dr. Shinji Inagaki 《Angewandte Chemie (International ed. in English)》2015,54(41):11999-12003
Nanoporous materials with functional frameworks have attracted attention because of their potential for various applications. Silica‐based mesoporous materials generally consist of amorphous frameworks, whereas a molecular‐scale lamellar ordering within the pore wall has been found for periodic mesoporous organosilicas (PMOs) prepared from bridged organosilane precursors. Formation of a “crystal‐like” framework has been expected to significantly change the physical and chemical properties of PMOs. However, until now, there has been no report on other crystal‐like arrangements. Here, we report a new molecular‐scale ordering induced for a PMO. Our strategy is to form pore walls from precursors exhibiting directional H‐bonding interaction. We demonstrate that the H‐bonded organosilica columns are hexagonally packed within the pore walls. We also show that the H‐bonded pore walls can stably accommodate H‐bonding guest molecules, which represents a new method of modifying the PMO framework. 相似文献
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A Hollow Foldecture with Truncated Trigonal Bipyramid Shape from the Self‐Assembly of an 11‐Helical Foldamer 下载免费PDF全文
Jae‐Hoon Eom Jintaek Gong Dr. Sunbum Kwon Dr. Aram Jeon Rokam Jeong Dr. Russell W. Driver Prof. Dr. Hee‐Seung Lee 《Angewandte Chemie (International ed. in English)》2015,54(45):13204-13207
The creation of self‐assembling microscale architectures that possess new and useful physical properties remains a significant challenge. Herein we report that an 11‐helical foldamer self‐assembles in a controlled manner to form a series of 3D foldectures with unusual three‐fold symmetrical shapes that are distinct from those generated from 12‐helical foldamers. The foldamer packing motif was revealed by powder X‐ray diffraction technique, and provides an important link between the molecular‐level symmetry and the microscale morphologies. The utility of foldectures with hollow interiors as robust and well‐defined supramolecular hosts was demonstrated for inorganic, organic, and even protein guests. This work will pave the way for the design of functional foldectures with greater 3D shape diversity and for the development of biocompatible delivery vehicles and containment vessels. 相似文献
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A series of iridium‐ and rhodium‐based hexanuclear organometallic cages containing 2,5‐dichloro‐3,6‐dihydroxy‐1,4‐benzoquinone, 9,10‐dihydroxy‐1,4‐anthraquinone, and 6,11‐dihydroxynaphthacene‐5,12‐dione ligands were synthesized from the self‐assembly of the corresponding molecular “clips” and 2,4,6‐tri(4‐pyridyl)‐1,3,5‐triazine ligands in good yields. These organometallic cages can form inclusion systems with a wide variety of π‐donor substrates, including coronene, pyrene, [Pt(acac)2], and hexamethoxytriphenylene. The 1:1 complexation of the resulting supramolecular assemblies was confirmed by 1H NMR spectroscopy. Large complexation shifts (Δδ>1 ppm) were observed in the 1H NMR spectra of guests in the presence of cage [Cp*6M6(μ‐DHNA)3(tpt)2](OTf)6 ( 6a ; M=Ir, tpt=2,4,6‐tri(4‐pyridyl)‐1,3,5‐triazine). The formation of discrete 1:1 donor–acceptor complexes, pyrene ?6 b (M=Rh), coronene ?6 a , coronene ?6 b , and [Pt(acac)2] ?6 a was confirmed by their single‐crystal X‐ray analyses. In these systems, the most important driving force for the formation of guest–host complexes is clearly the donor–acceptor π???π stacking interaction, including charge‐transfer interactions between the electron‐donating and electron‐accepting aromatic components. These structures provide compelling evidence for the existence of strong attractive forces between the electron‐deficient triazine core and electron‐rich guest. The results presented here may provide useful guidance for designing artificial receptors for functional biomolecules. 相似文献