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Inclusion Compounds (inclusion + compound)

Distribution by Scientific Domains

Chemistry	85%
Polymers and Materials Science	15%

Selected Abstracts

Structural Studies of ,-Cyclodextrin and Permethylated ,-Cyclodextrin Inclusion Compounds of Cyclopentadienyl Metal Carbonyl Complexes

EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 8 2006
Susana S. Braga
Abstract [CpM(CO)nCl] complexes with M = Fe (n = 2) and Mo (n = 3) have been immobilised in plain ,-cyclodextrin (,-CD) and permethylated ,-CD (TRIMEB) by methods tailored according to the stabilities and solubilities of the individual components. Four adducts were obtained with a 1:1 host/guest stoichiometry. The compounds were studied by powder X-ray diffraction (XRD), thermogravimetric analysis (TGA), 13C{1H} CP/MAS NMR and FTIR spectroscopy. A comparison of the experimental powder XRD data for the TRIMEB/[CpMo(CO)3Cl] inclusion compound with reference patterns revealed that the crystal packing is very similar to that reported previously for a TRIMEB/ethyl laurate inclusion compound. The unit-cell parameters refined to a = 14.731, b = 22.476, c = 27.714 Å (volume = 9176.3 Å3), and the space group was confirmed as P212121. A hypothetical structural model of the inclusion compound was subsequently obtained by global optimisation using simulated annealing. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006) [source]

Solid-State Photodimerization of Guest Molecules in Inclusion Compounds

EUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 18 2006
Irena Zouev
Abstract Photochemical dimerization reactions of 1,3-diphenyl-1-propen-3-one (chalcone), 9-acetylanthracene, and 9-(methoxycarbonyl)anthracene as guest molecules in inclusion compounds with 1,1,6,6-tetraphenyl-2,4-hexadiyne-1,6-diol were studied. The irradiation of a single crystal containing chalcone was carried out in a single step and resulted in a single crystal containing the photodimer in full occupancy. In the case of the crystal containing 9-acetylanthracene, X-ray diffraction data were collected after irradiation for different periods of time. Only one of the two crystallographically independent pairs of 9-acetylanthracene underwent solid-state photodimerization at ca. 11,% conversion to the head-to-tail dimer. Photodimerization of the 9-(methoxycarbonyl)anthracene inclusion compound led, after irradiation for 2.5 h, to ca. 37,% conversion. It was found that the molecules that were arranged in stacks had undergone photodimerization in two different ways, so that on the average it looked as if all the guest molecules had polymerized. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006) [source]

Inclusion Compounds of L,D-Dipeptide with Small Sulfoxides: Flexible Sheet Structure of (S)-Phenylglycyl-(R)-phenylglycine.

CHEMINFORM, Issue 51 2007
Motohiro Akazome
Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. [source]

Structural Studies of ,-Cyclodextrin and Permethylated ,-Cyclodextrin Inclusion Compounds of Cyclopentadienyl Metal Carbonyl Complexes

Solid-State Photodimerization of Guest Molecules in Inclusion Compounds

Molecular modelling of inclusion compounds from hydrophobic dyes and ,-cyclodextrin

COLORATION TECHNOLOGY, Issue 4 2009
Ahmed El-Shafei
This paper arises from studies aimed at developing new approaches to combining the fabric formation and coloration steps of fabric processing. A key aspect of these studies involved the evaluation of cyclodextrin (CD)-based compounds as hosts for dye molecules that could be released onto a fabric surface following fabric formation. In this study, experimental data from wide-angle X-ray diffraction and differential scanning calorimetry experiments were used in tandem with molecular modelling studies to confirm the formation of ,-CD,dye complex inclusion compounds and to demonstrate the utility of parameterised model number 3 (PM3) semi-empirical molecular modelling methods for predicting the nature of the preferred ,-CD,dye inclusion compounds. Calculations revealed that the inclusion compounds containing two dye molecules was preferred over the inclusion compound containing one dye molecule. Further, molecular modelling of the inclusion compound obtained using ,-CD linked to an epichlorohydrin-based oligomer and commercial disperse dyes showed inclusion compound formation to be an energetically favourable process. [source]

Drastic Solid-State Fluorescence Enhancement Behaviour of Phenanthro[9,10- d]imidazole-Type Fluorescent Hosts upon Inclusion of Carboxylic Acids

EUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 34 2009
Yousuke Ooyama
Abstract The crystals of phenanthro[9,10- d]imidazole-type fluorescent host 1 exhibit drastic fluorescence enhancement behaviour with a redshift in the emission maximum upon enclathration of various carboxylic acids such as formic acid, acetic acid and propionic acid. The optical changes are greatly dependent on the identity of the enclathrated carboxylic acids. The fluorescent clathrate compounds are formed not only by cocrystallization from carboxylic acid solutions but also by solid (fluorescent host),gas (carboxylic acid vapour) contact. Furthermore, when the acetic acid inclusion crystals are exposed to propionic acid vapour, acetic acid is gradually replaced by propionic acid. The guest exchange of the inclusion crystals was accompanied with colour and fluorescent intensity changes. The X-ray structural analyses of the guest-free and carboxylic acid inclusion compounds demonstrated that the destructions of the ,,, interactions, and the intermolecular hydrogen bonds binding fluorophores were induced by the enclathrated carboxylic acid molecules. Moreover, the imidazole ring of the host is protonated by the enclathrated carboxylic acid proton. On the basis of the spectroscopic data and the crystal structures, the effects of the enclathrated carboxylic acid on the solid-state photophysical properties of the clathrate compounds are discussed.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009) [source]

Solid-State Photodimerization of Guest Molecules in Inclusion Compounds

Oligophenylenevinylenes in Spatially Confined Nanochannels: Monitoring Intermolecular Interactions by UV/Vis and Raman Spectroscopy,

ADVANCED FUNCTIONAL MATERIALS, Issue 6 2008
Mariya Aloshyna
Abstract Perhydrotriphenylene-based channel-forming inclusion compounds (ICs) and thin films made of polyphenylenevinylene (PPV)-type oligomers with terminal alkoxy groups are investigated and compared in a combined experimental and theoretical approach. Interchromophore interactions and host-guest interactions are elucidated by UV/Vis and Raman spectroscopy. The impact of the local environment of the chromophore on the optical and photophysical properties is discussed in light of quantum-chemical calculations. In stark contrast to thin films where preferential side-by-side orientation leads to quenching of photoluminescence (PL) via non-emissive traps, the ICs are found to be attractive materials for opto-electronic applications: they offer high chromophore concentrations, but at the same time behave as quasi-isolated entities of tightly packed, well-oriented objects with high PL quantum yields and the possibility of color tuning. [source]

Alkaline hydrolysis of cinnamaldehyde to benzaldehyde in the presence of ,-cyclodextrin

AICHE JOURNAL, Issue 2 2010
Hongyan Chen
Abstract A facile, novel, and cost-effective alkaline hydrolysis process of cinnamaldehyde to benzaldehyde under rather mild conditions has been investigated systematically in the presence of ,-cyclodextrin (,-CD), with water as the only solvent. ,-CD could form inclusion complex with cinnamaldehyde in water, with molar ratio of 1:1, so as to promote the reaction selectivity. The complex has been investigated experimentally and with computational methods. 1H-NMR, ROESY, UV,Vis, and FTIR have been utilized to analyze the inclusion complex. It shows that the equilibrium constant for inclusion (Ka) is 363 M,1, and the standard Gibbs function for the reaction, ,,G (298 K), is ,14.6 kJ mol,1. In addition, the structures of the proposed inclusion compounds were optimized with hybrid ONIOM theory. Benzaldehyde could be obtained at an yield of 42% under optimum conditions [50°C, 18 h, 2% NaOH (w/v), cinnamaldehyde:,-CD (molar ratio) = 1:1]. To explain the experimental data, NMR, FTIR, and elemental analysis results were used to determine the main reaction by-product 1-naphthalenemethanol. A feasible reaction mechanism including the retro-Aldol condensation of cinnamaldehyde and the Aldol condensation of acetaldehyde and cinnamaldehyde in basic aqueous ,-CD solution has been proposed. The calculated activation energy for the reaction was 45.27 kJ mol,1 by initial concentrations method. © 2009 American Institute of Chemical Engineers AIChE J, 2010 [source]

Adduction of amiloride hydrochloride in urea through a modified technique for the dissolution enhancement

JOURNAL OF PHARMACEUTICAL SCIENCES, Issue 3 2008
Seema Thakral
Abstract Amiloride hydrochloride is a potassium-sparing diuretic since it favors sodium excretion and potassium reabsorption. In the present study, urea, a well-known adductor for linear compounds was successfully employed for inclusion of amiloride hydrochloride,a substituted cyclic organic compound through a modified technique. Formation of urea inclusion compounds was confirmed by FTIR, DSC and XRD. The minimum amount of rapidly adductible endocyte (RAE) required for adduction of amiloride hydrochloride in urea was estimated by a modified Zimmerschied calorimetric method. Urea,AH,RAE inclusion compounds containing varying proportions of guests were prepared and their thermal behavior studied by DSC. The inclusion compounds were also found to exhibit high content uniformity and markedly improved dissolution profile as demonstrated by increased dissolution efficiency. Studies reveal the possibility of exploiting co-inclusion of the drug in urea host lattice for the dissolution enhancement. © 2007 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 97:1191,1201, 2008 [source]

Why is Stereoregular Polyacrylonitrile Obtained by Polymerization in Urea Canals Isotactic?

MACROMOLECULAR THEORY AND SIMULATIONS, Issue 9 2007
Hyungchol Yang
Abstract Because stereoregular i-PAN is obtained from the constrained polymerization of acrylonitrile monomer in expandable urea clathrates, we studied the inclusion compounds formed between guest AN and PANs and host cyclodextrins whose rigid channel diameters are in the range of the canals in urea clathrates. ICs of AN were successfully formed with , - and , -CDs but did not yield PANs, and only ICs between , -CD, and a- and i-PANs were formed in solution. Modeling of AN and s- and i-PAN-CD-ICs were performed using PM3 parameters to estimate their stabilities. We conclude that the polymerization of AN in urea clathrate channels produces predominantly i-PAN as a consequence of its improved fit compared with s-PAN. [source]

Nanostructuring polymers with cyclodextrins,

POLYMERS FOR ADVANCED TECHNOLOGIES, Issue 2-3 2005
Cristian C. Rusa
Abstract Bulk solid polymer samples formed by the coalescence of guest polymer chains from their inclusion compounds (ICs) formed with host cyclodextrins (CDs) can result in significant reorganization of their phase structures, morphologies, and even chain conformations from those more commonly produced from randomly-coiled, entangled polymer solutions and melts. When the cyclic host CDs are threaded by polymer chains to form crystalline polymer-CD-ICs, the guest polymers become highly extended due to the narrow host CD diameters (,5, 7, and 9 Å for , -, , -, and , -CDs) and are segregated from neighboring guest polymer chains by the CD-IC channel walls. As a consequence, when polymer-CD-IC crystals are treated with CD solvents that do not dissolve the guest polymers or are treated with amylase enzymes, the resulting coalesced bulk polymer samples often display properties distinct from those of normally produced bulk samples of the same polymers. In this article the CD-IC processing of polymers to generate novel polymer microstructures and morphologies are described, to control the phase separation of immiscible blocks in block copolymers, and to form well-mixed intimate blends of two or more polymers that are normally incompatible. The thermal and temporal stabilities of polymer samples coalesced from their ICs formed with CDs will also be mentioned, and it is suggested that the range of polymer properties can be greatly expanded by their CD-IC processing. Copyright © 2005 John Wiley & Sons, Ltd. [source]

Structural effects on the solid-state photodimerization of 2-pyridone derivatives in inclusion compounds

ACTA CRYSTALLOGRAPHICA SECTION C, Issue 7 2009
Marina Telzhensky
The structures of six crystalline inclusion compounds between various host molecules and three guest molecules based on the 2-pyridone skeleton are described. The six compounds are 1,1,-biphenyl-2,2,-dicarboxylic acid,2-pyridone (1/2), C14H10O4·2C5H5NO, (I,a), 1,1,-biphenyl-2,2,-dicarboxylic acid,4-methyl-2-pyridone (1/2), C14H10O4·2C6H7NO, (I,c), 1,1,-biphenyl-2,2,-dicarboxylic acid,6-methyl-2-pyridone (1/2), C14H10O4·2C6H7NO, (I,d), 1,1,6,6-tetraphenyl-2,4-hexadiyne-1,6-diol,1-methyl-2-pyridone (1/2), C30H22O2·2C6H7NO, (II,b), 1,1,6,6-tetraphenyl-2,4-hexadiyne-1,6-diol,4-methy-2-pyridone (1/2), C30H22O2·2C6H7NO, (II,c), and 4,4,,4,,-(ethane-1,1,1-triyl)triphenol,6-methyl-2-pyridone,water (1/3/1), C20H18O3·3C6H7NO·H2O, (III,d). In two of the compounds, (I,a) and (I,d), the host molecules lie about crystallographic twofold axes. In two other compounds, (II,b) and (II,c), the host molecules lie across inversion centers. In all cases, the guest molecules are hydrogen bonded to the host molecules through O,H...O=C hydrogen bonds [the range of O...O distances is 2.543,(2),2.843,(2),Å. The pyridone moieties form dimers through N,H...O=C hydrogen bonds in five of the compounds [the range of N...O distances is 2.763,(2),2.968,(2),Å]. In four compounds, (I,a), (I,c), (I,d) and (II,c), the molecules are arranged in extended zigzag chains formed via host,guest hydrogen bonding. In five of the compounds, the guest molecules are arranged in parallel pairs on top of each other, related by inversion centers. However, none of these compounds underwent photodimerization in the solid state upon irradiation. In one of the crystalline compounds, (III,d), the guest molecules are arranged in stacks with one disordered molecule. The unsuccessful dimerization is attributed to the large interatomic distances between the potentially reactive atoms [the range of distances is 4.027,(4),4.865,(4),Å] and to the bad overlap, expressed by the lateral shift between the orbitals of these atoms [the range of the shifts from perfect overlap is 1.727,(4),3.324,(4),Å]. The bad overlap and large distances between potentially photoreactive atoms are attributed to the hydrogen-bonding schemes, because the interactions involved in hydrogen bonding are stronger than those in ,,, interactions. [source]

Induced circular dichroism in solid-state inclusion compounds

CHIRALITY, Issue 7 2001
Koichi Tanaka
Abstract In order to measure the circular dichroism (CD) spectrum in the solid state of a chiral compound which has no chromophore, an induced CD spectral method was developed by measuring the spectrum of the inclusion crystal of the chiral compound with a simple achiral aromatic host compound in the Nujol mulls. Chirality 13:347,350, 2001. © 2001 Wiley-Liss, Inc. [source]