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1.
Dr. Susana Ibáñez Prof. Eduardo Peris 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(17):6927-6932
A tetragold(I) rectangle-like metallocage containing two pyrene-bis-imidazolylidene ligands and two carbazolyl-bis-alkynyl linkers is used for the encapsulation of a series of polycyclic aromatic hydrocarbons (PAHs), including corannulene. The binding affinities obtained for the encapsulation of the planar PAHs guests in CD2Cl2 are found to exponentially increase with the number of π-electrons of the guest (1.3 > logK >6.6). For the bowl-shaped molecule of corannulene, the association constant is much lower than the expected one according to its number of electrons. The molecular structure of the host–guest complex formed with corannulene shows that the molecule of the guest is compressed, while the host is expanded, thus showing an interesting case of artificial mutual induced-fit arrangement. 相似文献
2.
《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2017,129(32):9601-9605
A homoditopic molecular host, janusarene, is presented that has two back‐to‐back compactly arranged nanocavities for guest complexation. The unique two‐face structural feature of janusarene allows it to bind and align various guest compounds concurrently, which include spherical pristine fullerene C60 and planar polycyclic aromatic hydrocarbons (PAHs), such as pyrene, perylene, and 9,10‐dimethylanthracene. The host–guest interactions were characterized by single‐crystal X‐ray diffraction. A pairwise encapsulation of the PAH guests by janusarene enables PAH dimers to be obtained that deliver spectroscopic properties distinct from those of PAHs dissolved in solution, or in the bulk state. A monotopic control host was also synthesized and used to characterize the host–guest complexing behavior in solution. 相似文献
3.
Norifumi Kishi Dr. Zhiou Li Dr. Yoshihisa Sei Prof. Dr. Munetaka Akita Dr. Kenji Yoza Prof. Dr. Jay S. Siegel Dr. Michito Yoshizawa 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(20):6313-6320
This article reports that an M2L4 molecular capsule is capable of encapsulating various neutral molecules in quantitative yields. The capsule was obtained as a single product by mixing a small number of components; two PdII ions and four bent bispyridine ligands containing two anthracene panels. Detailed studies of the host capability of the PdII‐linked capsule revealed that spherical (e.g., paracyclophane, adamantanes, and fullerene C60), planar (e.g., pyrenes and triphenylene), and bowl‐shaped molecules (e.g., corannulene) were encapsulated in the large spherical cavity, giving rise to 1:1 and 1:2 host–guest complexes, respectively. The volume of the encapsulated guest molecules ranged from 190 to 490 Å3. Within the capsule, the planar guests adopt a stacked‐dimer structure and the bowl‐shaped guests formed an unprecedented concave‐to‐concave capsular structure, which are fully shielded by the anthracene shell. Competitive binding experiments of the capsule with a set of the planar guests established a preferential binding series for pyrenes≈phenanthrene>triphenylene. Furthermore, the capsule showed the selective formation of an unusual ternary complex in the case of triphenylene and corannulene. 相似文献
4.
Theoretical prediction of the host–guest interactions between novel photoresponsive nanorings and C60: A strategy for facile encapsulation and release of fullerene
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Kun Yuan Jing‐Shuang Dang Yi‐Jun Guo Xiang Zhao 《Journal of computational chemistry》2015,36(8):518-528
A series of photoresponsive‐group‐containing nanorings hosts with 12~14 Å in diameter is designed by introducing different number of azo groups as the structural composition units. And the host–guest interactions between fullerene C60 and those nanoring hosts were investigated theoretically at M06‐2X/6‐31G(d)//M06‐L/MIDI! and wB97X‐D/6‐31G(d) levels. Analysis on geometrical characteristics and host–guest binding energies revealed that the designed nanoring molecule (labeled as 7 ) which is composed by seven azo groups and seven phenyls is the most feasible host for encapsulation of C60 guest among all candidates. Moreover, inferring from the simulated UV‐vis‐NIR spectroscopy, the C60 guest could be facilely released from the cavity of the host 7 via configuration transformation between trans‐form and cis‐form of the host under the 563 nm photoirradiation. Additionally, the frontier orbital features, weak interaction regions, infrared, and NMR spectra of the C60@7 host–guest complex have also been investigated theoretically. © 2015 Wiley Periodicals, Inc. 相似文献
5.
Dr. Bernd M. Schmidt Dr. Takafumi Osuga Dr. Tomohisa Sawada Dr. Manabu Hoshino Prof. Dr. Makoto Fujita 《Angewandte Chemie (International ed. in English)》2016,55(4):1561-1564
Self‐assembled coordination cages can be employed as a molecular press, where the bowl‐shaped guest corannulene (C20H10) is significantly flattened upon inclusion within the hydrophobic cavity. This is demonstrated by the pairwise inclusion of corannulene with naphthalene diimide as well as by the dimer inclusion of bromocorannulene inside the box‐like host. The compressed corannulene structures are unambiguously revealed by single‐crystal X‐ray analysis. 相似文献
6.
Abstract Two inclusion compounds of the 11-[bis(p‐chlorophenyl)hydroxymethyl]-9,10-dihydro-9,10-ethanoanthracene host (1) have been studied by X-ray diffraction in order to find an explanation of the exceptional clathrate formation ability of the present chloro-containing host as compared with that of closely related chlorine-free host analogues. Crystal data: 1·ethyl acetate (2:1), C27H22OCl2·½(C4H8O2), Mw = 501.45, P21/c, a = 8.9060(5), b = 11.1109(6), c = 25.642(1) Å, β = 99.03(1)°, Z = 4, R = 0.047 for 2029 F values with I>2σ(I); 1·cyclohexylamine (1:2), 2[C29H22OCI2·2(C6H13N)], Mw = 1311.50, Pc, a = 12.144(2), b = 12.689(3), c =23.119(8) Å, β = 91.68(1)°, Z = 2, R = 0.054 for 3073 F values with I>2σ(I). Although the two solid inclusion compounds differ in host‐guest stoichiometry, space group symmetry and also in host‐guest recognition mode, both co-crystals are held together by numerous C?H…X (X = O, N or Cl) interactions, in which the chloro-substituents of 1 play a very active role. The observed frequent participation of chlorine in intermolecular interactions in these compounds suggests an ability of the (C?)Cl substituents to effectively enhance the crystal formation in the absence of more dominant forces. 相似文献
7.
Hendrik Klien Wilhelm Seichter Konstantinos Skobridis Edwin Weber 《Acta Crystallographica. Section C, Structural Chemistry》2015,71(9):768-775
Having reference to an elongated structural modification of 2,2′‐bis(hydroxydiphenylmethyl)biphenyl, (I), the two 1,1′:4′,1′′‐terphenyl‐based diol hosts 2,2′′‐bis(hydroxydiphenylmethyl)‐1,1′:4′,1′′‐terphenyl, C44H34O2, (II), and 2,2′′‐bis[hydroxybis(4‐methylphenyl)methyl]‐1,1′:4′,1′′‐terphenyl, C48H42O2, (III), have been synthesized and studied with regard to their crystal structures involving different inclusions, i.e. (II) with dimethylformamide (DMF), C44H34O2·C2H6NO, denoted (IIa), (III) with DMF, C48H42O2·C2H6NO, denoted (IIIa), and (III) with acetonitrile, C48H42O2·CH3CN, denoted (IIIb). In the solvent‐free crystals of (II) and (III), the hydroxy H atoms are involved in intramolecular O—H...π hydrogen bonding, with the central arene ring of the terphenyl unit acting as an acceptor. The corresponding crystal structures are stabilized by intermolecular C—H...π contacts. Due to the distinctive acceptor character of the included DMF solvent species in the crystal structures of (IIa) and (IIIa), the guest molecule is coordinated to the host via O—H...O=C hydrogen bonding. In both crystal structures, infinite strands composed of alternating host and guest molecules represent the basic supramolecular aggregates. Within a given strand, the O atom of the solvent molecule acts as a bifurcated acceptor. Similar to the solvent‐free cases, the hydroxy H atoms in inclusion structure (IIIb) are involved in intramolecular hydrogen bonding, and there is thus a lack of host–guest interaction. As a result, the solvent molecules are accommodated as C—H...N hydrogen‐bonded inversion‐symmetric dimers in the channel‐like voids of the host lattice. 相似文献
8.
Luigi R. Nassimbeni Hong Su 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(6):o319-o322
The structures of the inclusion compounds 4,4′‐(cyclohexane‐1,1‐diyl)diphenol–3‐chlorophenol (1/1) and 4,4′‐(cyclohexane‐1,1‐diyl)diphenol–4‐chlorophenol (1/1), both C18H20O2·C6H5ClO, are isostructural with respect to the host molecule and are stabilized by extensive host–host, host–guest and guest–host hydrogen bonding. The packing is characterized by layers of host and guest molecules. The kinetics of thermal decomposition follow the R2 contracting‐area model, kt = [1 − (1 − α)½], and yield activation energies of 105 (8) and 96 (8) kJ mol−1, respectively. 相似文献
9.
Z. Takacs M. Soltesova J. Kowalewski J. Lang T. Brotin J.‐P. Dutasta 《Magnetic resonance in chemistry : MRC》2013,51(1):19-31
Cryptophane‐C is composed of two nonequivalent cyclotribenzylene caps, one of which contains methoxy group substituents on the phenyl rings. The two caps are connected by three OCH2CH2O linkers in an anti arrangement. Host–guest complexes of cryptophane‐C with dichloromethane and chloroform in solution were investigated in detail by nuclear magnetic resonance techniques and density functional theory (DFT) calculations. Variable temperature proton and carbon‐13 spectra show a variety of dynamic processes, such as guest exchange and host conformational transitions. The guest exchange was studied quantitatively by exchange spectroscopy measurements or by line‐shape analysis. The conformational preferences of the guest‐containing host were interpreted through cross‐relaxation measurements, providing evidence of the gauche+2 and gauche?2 conformations of the linkers. In addition, the mobility of the chloroform guest inside the cavity was studied by carbon‐13 relaxation experiments. Combining different types of evidence led to a detailed picture of molecular recognition, interpreted in terms of conformational selection. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
10.
Dr. Carlos Bartual‐Murgui Dr. Amal Akou Dr. Helena J. Shepherd Dr. Gábor Molnár Prof. Dr. J. Antonio Real Dr. Lionel Salmon Dr. Azzedine Bousseksou 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(44):15036-15043
A study of the spin‐crossover (SCO) behavior of the tridimensional porous coordination polymer {Fe(bpac)[Pt(CN)4]} (bpac=bis(4‐pyridyl)acetylene) on adsorption of different mono‐ and polyhalobenzene guest molecules is presented. The resolution of the crystal structure of {Fe(bpac)[Pt(CN)4]} ? G (G=1,2,4‐trichlorobenzene) shows preferential guest sites establishing π???π stacking interactions with the host framework. These host–guest interactions may explain the relationship between the modification of the SCO behavior and both the chemical nature of the guest molecule (electronic factors) and the number of adsorbed molecules (steric factors). 相似文献
11.
Mechanism of Host–Guest Complex Formation and Identification of Intermediates through NMR Titration and Diffusion NMR Spectroscopy
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M. Sc. Jan‐Hendrik Lamm B. Sc. Philipp Niermeier Dr. Andreas Mix Dr. Jasmin Chmiel Beate Neumann Dr. Hans‐Georg Stammler Prof. Dr. Norbert W. Mitzel 《Angewandte Chemie (International ed. in English)》2014,53(30):7938-7942
The formation of host–guest (H‐G) complexes between 1,8‐bis[(diethylgallanyl)ethynyl]anthracene (H) and the N‐heterocycles pyridine and pyrimidine (G) was studied in solution using a combination of NMR titration and diffusion NMR experiments. For the latter, diffusion coefficients of potential host–guest structures in solution were compared with those of tailor‐made reference compounds of similar shape (synthesized and characterized by NMR, HRMS, and in part XRD). Highly dynamic behavior was observed in both cases, but with different host–guest species and equilibria. With increasing concentrations of the pyridine guest, the equilibrium H2?H2κ1‐G1?HG2 is observed (in the second step a host dimer coordinates one guest molecule); for pyrimidine the equilibrium H2→H1κ2‐G1?HG2 is observed (the formation of a 1:1 aggregate is the second step). 相似文献
12.
Amphiphilic Inclusion Spaces for Various Guests and Regulation of Fluorescence Intensity of 1,8‐Bis(4‐aminophenyl)anthracene Crystals
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Misa Sugino Keisuke Hatanaka Yusuke Araki Dr. Ichiro Hisaki Prof. Dr. Mikiji Miyata Dr. Norimitsu Tohnai 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(11):3069-3076
A host framework for inclusion of various guest molecules was investigated by preparation of inclusion crystals of 1,8‐bis(4‐aminophenyl)anthracene (1,8‐BAPA) with organic solvents. X‐ray crystallographic analysis revealed construction of the same inclusion space incorporating 1,8‐BAPA and eight guest molecules including both non‐polar (benzene) and polar guests (N,N‐dimethylformamide, DMF). Fluorescence efficiencies varied depending on guest molecule polarity; DMF inclusion crystals exhibited the highest fluorescence intensity (ΦF=0.40), four times as high as that of a benzene inclusion crystal (ΦF=0.10). According to systematic investigations of inclusion phenomena, strong host–guest interactions and filling of the inclusion space led to a high fluorescence intensity. Temperature‐dependent fluorescence spectral measurements revealed these factors effectively immobilised the host framework. Although hydrogen bonding commonly decreases fluorescence intensity, the present study demonstrated that such strong interactions provide excellent conditions for fluorescence enhancement. Thus, this remarkable behaviour has potential application toward sensing of highly polar molecules, such as biogenic compounds. 相似文献
13.
Tomoya Nishioka Kiyonori Kuroda Munetaka Akita Michito Yoshizawa 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(20):6651-6655
A gemini‐type amphiphilic molecule, constituted of two V‐shaped polyaromatic amphiphiles linked by a linear acetylene spacer, was synthesized. The gemini amphiphile assembles into a well‐defined aromatic micelle (ca. 2 nm in core diameter), providing higher stability in water even at low concentration (0.09 mm ) and high temperature (>130 °C). Unlike common gemini amphiphiles with aliphatic chains, the present amphiphile and its micellar assembly emit green and orange fluorescence (ΦF=33 and 9 %), respectively. Despite strong and multiple π‐stacks of the polyaromatic panels of the amphiphiles, the water‐soluble gemini aromatic micelle incorporates medium‐size to large hydrophobic compounds into the frameworks. Interestingly, the guest binding capability toward large planar molecules was enhanced by more than two times through the pre‐encapsulation of spherical molecules in the cavity. 相似文献
14.
Juan Gu Shao‐Ming Chi Yong Zhao Ping Zheng Qiong Ruan Yan Zhao Hong‐You Zhu 《Helvetica chimica acta》2011,94(9):1608-1617
The inclusion‐complexation behavior of coenzyme Q10 (CoQ10) with the three polyamine‐modified β‐cyclodextrins (CDs) 1 – 3 was investigated in both solution and the solid state by means of NMR, XRD, and FT‐IR spectroscopy. The results showed that the apparent solubility of CoQ10 increased linearly upon addition of hosts 1 – 3 , giving AL‐type phase‐solubility curves. These hosts 1 – 3 were able to solubilize CoQ10 to high levels, up to 1.35, 1.52, and 1.44 mg/ml (calculated as CoQ10), respectively. The host 2 with a moderate‐length chain is the most suitable for inclusion complexation of CoQ10. Accroding to the ROESY experiments, the MeO groups of CoQ10 and the tether of 2 can be co‐included into the cavity of β‐CD through the induced‐fit interaction between host and guest. The binding ability of modified β‐CDs 1 – 3 upon complexation with CoQ10 are discussed from the viewpoints of the size/shape‐matching relationship and the induced‐fit concept between host CDs and guest CoQ10 molecule. 相似文献
15.
Yan Zhao Yong Cun Yang Shao Ming Chi Hao Shi Yong Zhao Hong You Zhu Qi Lin Li Yu Fei Wang 《Helvetica chimica acta》2010,93(5):999-1011
A novel 4,4′‐sulfonyldianiline‐bridged bis(β‐cyclodextrin (CD)) 2 was synthesized, and its complex stability constants (Ks) for the 1 : 1 inclusion complexation with bile salts, i.e., cholate (CA), deoxycholate (DCA), glycocholate (GCA), and taurocholate (TCA) have been determined in phosphate buffer (pH 7.2) at 25° by fluorescence spectroscopy. The result indicated that 2 can act as efficient fluorescent sensor and display remarkable fluorescence enhancement upon addition of optically inert bile salts. Structures of the inclusion complexes between bile salts and 2 were elucidated by 2D‐NMR experiments, indicating that the anionic tail group and the D ring of bile salts penetrate into one CD cavity of 2 from the wide opening deeply, while the phenyl moiety of the CD linker is partially self‐included in the other CD cavity to form a host–linker–guest binding mode. As compared with native β‐CD 1 upon complexation with bile salts, bis(β‐CD) 2 enhances the binding ability and molecular selectivity. Typically, 2 gives the highest Ks value of 26200 M ?1 for the complexation with CA, which may be ascribed to the simultaneous contributions of hydrophobic, H‐bond, and electrostatic interactions. These phenomena are discussed from the viewpoints of multiple recognition and induce‐fit interactions between host and guest. 相似文献
16.
Ana Gabriela Arvízu-Santamaría Yedith Soberanes Enrique F. Velázquez Hisila Santacruz Motomichi Inoue 《Supramolecular chemistry》2017,29(9):658-667
The 1H NMR signals of the titled neurotransmitters undergo up-field shift accompanied by line-broadening in NMR titration with the DTPA-based cyclophane at pD 7.3; the cyclophane consists of a 4,4′-bis(1,1′-biphenyl-4,4′-dihydroxy)dianiline unit cyclised by a DTPA (diethylenetriaminepentaacetate) group through two amide linkages. Changes in chemical shifts of dopamine indicate the formation of a 1:1 complex with the formation constant K1 400 M?1; the complex of serotonin is likely to form a 2:1 host?guest complex with β2 ≈ 105 M?2; melatonin does not form a complex with definite stoichiometry. The primary binding forces in the dopamine and serotonin complexes are electrostatic interaction between cationic neurotransmitter and anionic cyclophane molecules, and the resulting ionic pairs are stabilised by encapsulation. The electrostatic interaction is weakened by electrolytes; in 0.1 M Trizma buffer, dopamine does not yield a definite complex, and serotonin forms a 1:1 complex with K1 80 M?1. Extreme line-broadening of neurotransmitter signals suggests that the molecular motion of the guest molecule is slowed in the complex by interactions with the receptor molecule whose internal molecular motion is quenched partially. The high rigidity of the cyclophane enhances intermolecular interaction in the hydrophobic regions to prolong the lifetime of the complex. 相似文献
17.
Andrew Bond William Jones 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(4):436-437
The title compound, [Mg(C5H4NOS)2(H2O)2]·C10H8N2O2S2, is a two‐component host–guest material. The 2,2′‐dithiobis(pyridine N‐oxide) molecule has crystallographic twofold symmetry. The metal complex lies on an inversion centre and associates via C—H?S interactions into chains which thread the 2,2′‐dithiobis(pyridine N‐oxide) lattice in perpendicular directions. Hydrogen bonds exist between the water molecules of the diaquamagnesium units and the N—O groups of the host lattice. 相似文献
18.
Yuji Koga Kouki Matsubara 《Journal of polymer science. Part A, Polymer chemistry》2009,47(17):4358-4365
We prepared an iridium polymer complex having 2‐phenylpyridine as a η2‐cyclometallated ligand, a new OLED containing a solution‐processible iridium polymer as a host, and a phosphorescent iridium complex, [Ir(piq‐tBu)3] as a guest. This is the first example to apply a phosphorescent iridium complex polymer to a host material in a phosphorescent OLED. A phosphine copolymer ligand made from methyl methacrylate (MMA) and 4‐styryldiphenylphosphine can be used as an anchor polymer, which coordinates to luminescent iridium units to form a host metallopolymer easily. The OLED containing the host iridium‐complex polymer film, in which the guest, 2 wt % Ir(piq‐tBu)3, was doped, showed red electroluminescence as a result of efficient energy transfer from the iridium polymer host to the iridium guest. The maximum current efficiency of the device was 1.00, suggesting that a soluble iridium complex polymer can be used as a solution‐processible polymer host in EL devices. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 4358–4365, 2009 相似文献
19.
Ilia A. Guzei Kelsey C. Miles 《Acta Crystallographica. Section C, Structural Chemistry》2016,72(3):179-183
The crystal structure and absolute configuration of a molecular host/guest/impurity inclusion complex were established unequivocally in spite of our having no prior knowledge of its chemical composition. The host (4R,5R)‐4,5‐bis(hydroxydiphenylmethyl)‐2,2‐dimethyl‐1,3‐dioxolane, (I), displays expected conformational features. The crystal‐disordered chiral guest 4,4a,5,6,7,8‐hexahydronaphthalen‐2(3H)‐one, (II), is present in the crystal 85.1 (4)% of the time. It shares a common site with 4a‐hydroperoxymethyl‐4,4a,5,6,7,8‐hexahydronaphthalen‐2(3H)‐one, (III), present 14.9 (4)% of the time, which is the product of autoxidation of (II). This minor peroxide impurity was isolated, and the results of nuclear magnetic resonance, mass spectrometry, and X‐ray fluorescence studies are consistent with the proposed structure of (III). The complete structure was therefore determined to be (4R,5R)‐4,5‐bis(hydroxydiphenylmethyl)‐2,2‐dimethyl‐1,3‐dioxolane–4,4a,5,6,7,8‐hexahydronaphthalen‐2(3H)‐one–4a‐hydroperoxymethyl‐4,4a,5,6,7,8‐hexahydronaphthalen‐2(3H)‐one (1/0.85/0.15), C31H30O4·0.85C10H14O·0.15C10H14O3, (IV). There are host–host, host–guest, and host–impurity hydrogen‐bonding interactions of types S and D in the solid state. We believe that the crystals of (IV) were originally prepared to establish the chirality of the guest (II) by means of X‐ray diffraction analysis of host/guest crystals obtained in the course of chiral resolution during cocrystallization of (II) with (I). In spite of the absence of `heavy' elements, the absolute configurations of all anomeric centres in the structure are assigned as R based on resonant scattering effects. 相似文献
20.
Aude Bouchet Thierry Brotin Dr. Dominique Cavagnat Dr. Thierry Buffeteau Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(15):4507-4518
We report the synthesis of the water‐soluble cryptophanol derivative 1 and the study of the chiroptical properties of its two enantiomers (>99 % ee) by polarimetry, electronic circular dichroism (ECD), and vibrational circular dichroism (VCD). We show that cryptophanol 1 exhibits unusual chiroptical properties in water under basic conditions (pH>12). For instance, the shapes of the ECD and VCD spectra of 1 in water were strongly dependent on the nature of the alkali metal ions (Li+, Na+, K+, Cs+) surrounding the cryptophane and whether or not a guest molecule is present inside the cavity of the host. To the best of our knowledge, this is the first example in which the nature of these counterions governs the chiroptical properties of a host molecule. Moreover, specific ECD spectra were obtained depending on the size of the guest molecules. This makes 1 a good sensor for small neutral molecules in aqueous solvent. Finally, VCD experiments associated with DFT calculations show that the chiroptical changes can be directly correlated to the presence of charges close to the aromatic rings and with a conformational change of the alkyl chains upon encapsulation. 相似文献