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1.
The preparation and inclusion properties of the new halo aryl hosts, 2,2′,7,7′,9,9′-hexahalo-9,9′-bisfluorenyl derivatives 5-7, are described. The host compounds 5-7 having four halogen atoms on the aromatic rings form stable inclusion crystals with many guest compounds, whereas the parent compound 4 does not. The X-ray structures of the host 4 and representative inclusion compounds of hosts 5-7 were determined, allowing rationalization of several of the experimental observations. 相似文献
2.
Novel terephthalic acid host compounds having aromatic substituent 1-4 have been prepared and their inclusion properties were investigated. These host compounds enclathrated several kinds of alcohols, ethers, ketones, amides, and sulfoxides. The X-ray structures of 1:1 2a/EtOH, 1:2 2b/DMF, 1:2 3/MeOH, and 1:1 4/EtOH complexes revealed complexation mode. 相似文献
3.
Ingeborg Csöregh Thomas Brehmer Silke I. Nitsche Wilhelm Seichter Edwin Weber 《Journal of inclusion phenomena and macrocyclic chemistry》2003,47(3-4):113-121
X-ray crystal structures are reported of a free host compound 1, comprising two diphenylmethanol terminal groups attached to a central 9,10-ethynyl substituted anthracene unit, and of three inclusion compounds of a fluoren-9-ol substituted analogous host 2 with acetone, dimethyl sulphoxide (DMSO) and dimethylformamide (DMF) as guest, respectively. Despite the presence of two hydroxyl groups in 1, there is no O–H...O hydrogen bond between the molecules in the guest free crystal – only weaker C–H...O interactions and van der Waals' type connections. In the inclusion compounds of 2, H-bonded 1:2 host–guest associates are formed, where each of the host hydroxyl groups binds to a guest oxygen atom. The orientations of the host–guest connections in these complexes vary, being E for acetone and Z for both DMSO and DMF guests, relative to the host anthracene unit. The DMSO and DMF inclusion compounds of 2 proved to be isostructural. 相似文献
4.
Satish Balasaheb NimseJunbae Kim Keum-Soo Song Junghoon Kim Jeong Tae LeeVan-Thuan Nguyen Van-Thao TaTaisun Kim 《Tetrahedron letters》2011,52(29):3751-3755
In this Letter, the role of the depth of the cavity in the recognition processes of the guests by the hosts has been investigated. The hosts 2, 3 interact with both the cationic function and the aromatic moiety in the guests 5, 6 but with a slight preference for the cationic functions. The host 4 selectively recognizes the trimethylammonium functions of the guests 5 and 6. However, the host 1 selectively recognizes the aromatic moiety of the ditopic trimethylammonium guests 5 and 6. The recognition and orientation of the guest in the cavity of the host are directly dependent on the depth of the hydrophobic cavity of the host. 相似文献
5.
Satish Balasaheb Nimse Junghoon Kim Keum-Soo Song Chan-Yong Jung Sudhakara Reddy Seelam 《Tetrahedron letters》2010,51(21):2840-551
We report the new water-soluble aminocalix[4]arene hosts 1 and 2 with deep hydrophobic cavity facilitating hydrophobic mouth and hydrophilic mouth, respectively. The 1H NMR titrations revealed that host 1 shows high selectivity for neutral guests 9 and 10, with log K of 4.2 and 4.6, respectively. The host 2 shows log K of 4.9 for binding with guest 15. Moreover, the binding ability of the host 2 for guest 14 is stronger by a factor of 1000 than that of the host 1. 相似文献
6.
Naoya Morohashi Kohei Ebata Tetsutaro Hattori 《Journal of inclusion phenomena and macrocyclic chemistry》2018,90(3-4):279-285
Upon stirring inclusion crystals of p-tert-butylthiacalix[4]arene (2) in solvents with heating, guest compounds were efficiently desorbed to yield guest-free crystals. More specifically, upon treatment with methanol, the exchange of guest compounds with methanol in the crystals, followed by the desorption of the methanol afforded metastable host crystals 2β, whereas, upon treatment with heptane, the dissolution of the inclusion crystals and simultaneous crystallization of compound 2 afforded stable host crystals 2α. Further, a host crystal of p-tert-butylcalix[4]arene (1) was recovered by the treatment of 2:1 (host/guest) inclusion crystals of compound 1 with supercritical carbon dioxide (scCO2), and through the combination of the guest exchange of 1:1 inclusion crystals of compound 1 with hexane and scCO2 treatment of the resulting 2:1 inclusion crystals 12·hexane. Although the recovered host crystal of compound 1 contained a small amount of CO2, it could be reused for the inclusion of organic compounds. 相似文献
7.
Three perfluorinated host compounds of the triazine type, namely 2,4,6-tris(pentafluorophenoxy)-1,3,5-triazine (1), 2,4,6-tris(pentafluorothiophenoxy)-1,3,5-triazine (2) and 2,4,6-tris(pentafluorophenamin)-1,3,5-triazine (3), were synthesized differing only in the linking heteroatom (O, S and NH) between the triazine core and the pentafluorophenyl groups. The crystal structures involving compounds 1, 2 and their inclusion compounds are dominated by a variety of fluorine interactions (phenyl-perfluorophenyl, C-H?F, F?F, C-F?πF). However, in the structure of 3, possessing additional hydrogen atoms of the linkage NH-groups, the formation of hydrogen bonds is favoured, whereas fluorine contacts are less apparent. Investigations by powder X-ray diffraction and thermogravimetric analysis revealed substantial differences in the host-guest interactions of the inclusion compounds. 相似文献
8.
Alan S.F. BoydGraeme Cooke Florence M.A. DuclairoirVincent M. Rotello 《Tetrahedron letters》2003,44(2):303-306
We have investigated the electrochemically controlled hydrogen bonding interactions between tetrathiafulvalene host 3 and guests 4 or 5. Stabilisation of the 3+ state is dependent upon the nature of the guest species, whereas both guests prevent precipitation of the electrochemically generated 32+ species at the working electrode via hydrogen bonded molecular recognition processes. 相似文献
9.
Tobias Gruber Max Peukert Diana Schindler Wilhelm Seichter Edwin Weber Petra Bombicz 《Journal of inclusion phenomena and macrocyclic chemistry》2008,62(3-4):311-324
Three lower rim n-propyl substituted calix[4]arenes (1–3) with varied number and position of the modifying groups have been prepared. Inclusion compounds (five species) involving different kinds of guest solvents have been isolated. Their X-ray crystal structures were determined and comparatively discussed using isostructurality calculations. Two of the inclusion compounds obtained (1a and 1b) are polymorphs containing the same host and guest molecules in equal stoichiometric ratio but different Z′ values caused by a phase transition around 140 K. The inclusion compounds 2a and 2b refer to the interesting case of a mixed solvent complex while 3a allows studying the effect of full lower rim n-propyl substitution. 相似文献
10.
Hosuk Ryu 《Tetrahedron》2006,62(26):6236-6247
The series of cyano-substituted model compounds 18-20 for organic light emitting diodes (OLEDs) was prepared through Knoevenagel condensation reactions between the dialdehydes 3,6,9 and the differently substituted acetonitrile derivatives 11,16,17. The influence of the different substituents on the optical properties of the resulting α-cyanostyryl compounds 18-20 was investigated. Another series of dimeric cyano-substituted styryl compounds 26-28 were prepared, in which a flexible, nonconjugated spacer is present between the two cyanostyryl moieties. The spacer isolates the π-conjugated portions of dimeric compounds 26-28, improves their solubility in common organic solvents, and decreases their tendency to crystallize. These features are favorable for producing efficient luminescent films in OLEDs devices. 相似文献
11.
Kira E. Vostrikova Eugenia V. PeresypkinaValeri A. Drebushchak Vladimir A. Nadolinny 《Polyhedron》2011,30(18):3083-3087
A nitronyl nitroxide, 2-(benzimidazolyl)-4,4,5,5,-tetramethylimidazolidinyl-3-oxide-1-oxy, 1 and its imino nitroxide analog 2, have been included in cucurbit[n]urils, CBn (n = 7,8), as their hydrochlorides and neutral compounds as well. The hydrochlorides form soluble 1:1 complexes. In the solid state the paramagnetic centers are well isolated and magnetic interactions are cancelled out in contrast to what is observed for the pure nitroxides. The two inclusion complexes involving 1 were characterized by X-ray crystallography. When they were heated in the solid state, one observed a clean conversion of the nitronyl nitroxide guest, 1, into its analog 2. 相似文献
12.
Ryo Katoono 《Tetrahedron letters》2006,47(10):1513-1518
Conformation of novel terephthalamide hosts 1 changes from anti to syn upon complexation with a bidentate guest (2 or 3). Chiral sense in the helical syn-form of the double-armed host molecules 1 is biased by the asymmetric centers on the chiral guest [(R,R)/(S,S)-2a], which can be detected by the drastic change in circular dichroism (CD) spectrum thanks to the exciton coupling of two chromophores (‘arms’) linked to the amide nitrogens. Asymmetric centers on the host molecule also exhibit preference for the twisting direction upon change in geometry from the anti- to syn-form. Thus, the achiral guests (2b or 3) can also be detected by modulation of CD spectrum upon complexation with the chiral host [(R,R)-1a]. 相似文献
13.
The inclusion of tetramethylammonium and ditopic trimethylammonium cations by the water-soluble pentasulfonatocalix[5]arene 1 has been studied at neutral pH by 1H NMR and compared with the homologous tetrasulfonatocalix[4]arene 2. Unlike host 2, host 1 selectively binds the ditopic trimethylammonium ions by three different non-covalent interactions. Remarkably the flexible host 1 exhibits both more efficiency and selectivity in the complexation of ditopic methylammonium ions with respect to similar more preorganised calix[4]arene receptors. 相似文献
14.
Two β-cyclodextrin-C60 conjugates (3 and 4) with a flexible linker at the secondary face of cyclodextrin are synthesized by a single reaction of 2-(ω-azidoundecanyl)-2-O-heptakis (2,3,6-tri-O-methyl)-β-cyclodextrin (2) and C60, both of which display satisfactory water solubility. Structural analyses show that 3 is a closed [5,6] aziridinofullerene, whereas 4 is a bis-adduct derivative. Using rhodamine B (RhB) as a guest molecule, the inclusion complexation behavior of 3 was investigated in aqueous solution. 相似文献
15.
Corinne L.D. Gibb 《Tetrahedron》2009,65(35):7240-7248
Guests covering a range of polarities were examined for their ability to bind to a water-soluble cavitand and trigger its assembly into a supramolecular capsule. Specifically the guests examined were: tridecane 2, 1-dodecanol 3, 2-nonyloxy ethanol (ethylene glycol monononyl ether) 4, 2-(2-hexyloxyethoxy) ethanol (di(ethylene glycol) hexyl ether) 5, 2-[2-(2 propoxyethoxy)ethoxy] ethanol (tri(ethylene glycol) propyl ether) 6, and bis [2-(2-hydroxyethoxy)ethyl] ether (tetra(ethylene glycol)) 7. In this series, guest 6 proved to signify the boundary between assembly and the formation of 2:1 complexes, and simple 1:1 complexation. Thus, guests 2-5 formed relatively kinetically stable capsules, guest 6 formed a capsule that was unstable relative to the NMR timescale, and guest 7 formed a simple 1:1 complex. 相似文献
16.
Hitomi Kitagawa Ryosuke Kitagawa Masamichi Yamanaka Kenji Kobayashi 《Tetrahedron》2009,65(35):7234-914
Tetra(4-pyridyl)-cavitand 1 and tetrakis(4-hydroxyphenyl)-cavitand 2 self-assemble into a heterodimeric capsule 1·2 via four PhOH?pyridyl hydrogen bonds in CDCl3, wherein one molecule of 1,4-disubstituted-benzene as a guest is encapsulated to form a ternary complex, guest@(1·2). The X-ray crystallographic analysis of (methyl p-ethoxybenzoate)@(1·2) confirmed that the methyl ester and ethoxy groups of the encapsulated guest are oriented to the cavity ends of the 1 and 2 units, respectively. The scope and limitation of guest encapsulation in 1·2, including guest-binding selectivity and orientational isomeric selectivity, are described from the viewpoint of size complementarity and CH-π, CH-halogen, and halogen-π interactions between guest and the cavity of 1·2. 相似文献
17.
To investigate alkali metal complexation with sulfur-linked calixarene analogues and their guest-binding properties for gaseous organic guest molecules, we elucidated a crystal structure of a cesium complex with p-H-thiacalix[4]arene (1·4H) ligands and guest-binding properties of the cesium complex (2) and the previously reported rubidium complex (3). In crystals of the complex 2, a ‘sandwich-like’ binuclear complex was formed by inter-molecular coordination of cesium cations to the thiacalixarene molecules and methanol molecules, mutually interacting by aromatic-H?S hydrogen bonding and alkali metal cation-π interactions between the alkali metal cation and thiacalixarene aromatic rings outside of the cavities. On the guest-binding behaviors both complexes 2 and 3 toward organic guest molecules, methanol, ethanol, and 1-propanol as polar molecules, the complex 2 has no methanol adsorption ability, but the complex 3 showed vapor adsorption properties for all guest molecules. In particular, both complexes exhibited a high adsorption capability toward ethanol molecule. As results of gaseous guest adsorption measurements for alcohol molecules, the guest-binding of these complexes are significantly different because the properties depend heavily on structural natures between complexes 2 and 3. 相似文献
18.
Vamsee Krishna Muppidi 《Journal of solid state chemistry》2007,180(1):132-137
The physical properties of [CuL12(H2O)] (1) and [CuL22(H2O)] (2) and preparation and crystal structures of the inclusion compounds 1·(P)-C2H4Br2, 2·(M)-C2H4Br2, 1·CH3CN and 2·CH3CN are described. HL1 and HL2 (H represents the dissociable phenolic proton) are the N,O-donor chiral reduced Schiff bases N-(2-hydroxy-5-nitrobenzyl)-(R)-α-methyl-benzylamine and N-(2-hydroxy-5-nitrobenzyl)-(S)-α-methylbenzylamine, respectively. All the compounds crystallize in the non-centrosymmetric space group C2. In the crystal lattice, the host [CuLn2(H2O)] (1 and 2) molecules connected by O−H?O and C−H?O interactions form perfectly polar two-dimensional networks. In these chiral and polar host frameworks, enantiospecific inclusion with polar ordering of the right-handed (P) and the left-handed (M) gauche form of 1,2-dibromoethane as well as polar alignment of acetonitrile molecules are observed. The host and guest molecules are linked by C−H?O interactions. The O-atoms of the nitro substituent on the ligands of 1 and 2 act as the acceptors in all these intermolecular O−H?O and C−H?O interactions. The structures reported in this work provide rare examples of enantiospecific trapping of the chiral rotamers of 1,2-dibromoethane as well as perfectly polar alignment of both guest and host molecules. 相似文献
19.
Three 9-substituted anthracene derivatives, that is, 9-hydroxymethylanthracene (2), 9-methoxymethylanthracene (3) and bis(9-anthrylmethyl) adipate (6), were chosen as the model compounds to evaluate the reactivity in their Diels-Alder reactions with [60]fullerene and in retro Diels-Alder reactions of the formed cycloadducts. Corresponding adducts 4, 5 and 7 were prepared in high yields under solvent-free conditions using high-speed vibration milling technique. In order to determine thermal stabilities of adducts 4, 5 and 7, their dissociations in the temperature range of 40-65 °C were investigated. Fitting the dissociation rates and temperatures to the Arrhenius equation gives the activation energies of 25.8, 21.8 and 24.9 kcal/mol for compounds 4, 5 and 7, respectively. 相似文献
20.
Yeon Sil Park 《Tetrahedron letters》2010,51(30):3956-3959
Tetrapyridinohemicarcerand 2 having four hydrogen-bonding acceptors of inward-directing pyridyl units was synthesized and their binding properties for a variety of organic guest molecules have been investigated. Tetrapyridinohemicarcerand 2 formed kinetically stable complexes with various sulfonic acids via intermolecular -SO3H-pyridyl hydrogen bonding and constrictive binding interactions in C2D2Cl4 at 25 °C. But carboxylic acids or alcohols cannot be a stable guest at the same conditions. Tetrapyridinohemicarcerand 2 also binds various disubstituted benzenes. Especially 1,4-diiodobenzene forms stable hemicarceplex 1,4-diiodobenzene@2, which seems to be stabilized by constrictive binding as well as by -C-H?I interactions between dioxymethylene of 2 and iodo group of guest. 相似文献