0000000001303690

AUTHOR

Michael Bolte

showing 49 related works from this author

New Molecular Topologies by Fourfold Metathesis Reactions within a Hydrogen-Bonded Calix[4]arene Dimer

2003

A calix[4]arene tetrapentyl ether in the cone conformation substituted at its wide rim by four m-(omega-octenyloxy)phenyl urea groups forms hydrogen-bonded dimeric capsules in dichloromethane/benzene (95:5). Metathesis reaction with Grubbs' catalyst under high-dilution conditions (1.1 x 10(-4) M) followed by hydrogenation leads to a covalent connection of all the urea groups within a dimer. Three topologically different products may be expected in such a reaction: a bis[2]catenane, a doubly bridged monocatenane and a tetrabridged capsule. All three possible reaction products could be isolated in an overall yield up to 60 % for the separated and purified compounds. Their identification was b…

CyclohexaneStereochemistryDimerOrganic ChemistryCatenaneEtherGeneral ChemistryMetathesisCatalysischemistry.chemical_compoundCrystallographychemistryCovalent bondCalixareneSalt metathesis reactionChemistry - A European Journal
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2,2′-Dimethyl-2,2′-(m-phenyl­ene­dimethyl­ene)propane­dinitrile

2009

The title compound, C16H14N4, features an aromatic ring with two 2,2´-dicyanopropyl residues in positions 1 and 3, which are located above and below the ring plane. The two residues differ in their conformation with respect to the aromatic ring: whereas one of the Cmethyl-C-Cmethylene-Caromatic torsion angles is gauche [68.93 (12)°], the other one is fully staggered [177.63 (9)°]. The crystal structure is stabilized by C-H...N hydrogen-bonding interactions. Key indicators: single-crystal X-ray study; T = 173 K; mean σ(C–C) = 0.002 Å; R factor = 0.037; wR factor = 0.101; data-to-parameter ratio = 15.0.

chemistry.chemical_compoundchemistryPropaneddc:540General Materials ScienceGeneral ChemistryCrystal structureRing planeCondensed Matter PhysicsBioinformaticsMedicinal chemistryOrganic PapersEne reactionActa Crystallographica Section E: Structure Reports Online
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Tetra-urea calix[4]arenes 1,3-bridged at the narrow rim.

2009

The synthesis of special tetra-urea calix[4]arene derivatives is described. Two propyl ether groups in 1,3-position and a 5-iodo-isophthalamide bridge connecting two aminopropylether residues in 2,4-position at the narrow rim keep the molecule fixed in the cone conformation. The aryl urea residues are substituted by decyloxy groups in p-position to increase the solubility in apolar solvents, while the iodo substituent allows further functionalization. Two single crystal X-ray structures of 3 and 4 show a strongly pinched cone conformation in which the bridged phenol units are bent outwards, while the phenol units bearing the propyl ether groups are nearly parallel. The molecules are flexibl…

biologyStereochemistryArylOrganic ChemistrySubstituentbiology.organism_classificationBiochemistrychemistry.chemical_compoundchemistryPolymer chemistryUreaTetraMoleculePhenolPhysical and Theoretical ChemistrySolubilitySingle crystalOrganicbiomolecular chemistry
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Multiple Catenanes Derived from Calix[4]arenes

2004

A multicatenane is described in which two belts consisting of four annelated rings attached to the wide rims of two calix[4]arenes are interwoven in such a way that each ring of one belt penetrates two adjacent rings of the other belt and vice versa. The key step of the synthesis of this [8]catenane is the exclusive formation of preorganized heterodimers between a multimacrocyclic tetraurea calix[4]arene and an “open-chain” tetraurea calix[4]arene containing eight ω-alkenyl groups. When a tetraurea calix[4]arene containing four alkenyl groups is used, a bis-[3]catenane is formed analogously.

MultidisciplinaryChemistryStereochemistryCatenaneRing (chemistry)Science
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Cyclic tetraureas with variable flexibility--synthesis, crystal structures and properties.

2008

Macrocyclic molecules containing several amide or urea functions may serve as anion receptors. We describe the synthesis of 32-membered macrocycles, in which four rigid xanthene units (X) and/or diphenyl ether units (D) as flexible analogues are linked via urea groups. All six possible combinations of these units (XXXX, XXXD, XXDD, XDXD, XDDD and DDDD) were synthesized and two examples were characterised by single-crystal X-ray analyses (DDDD and two structures for XXXD). Both macrocycles showed distinct differences in their overall conformation and consequently in their hydrogen-bonding pattern. Hydrogen-bonded solvent molecules are found for both compounds and intramolecular hydrogen bond…

XantheneModels MolecularMagnetic Resonance SpectroscopyMolecular StructureStereochemistryHydrogen bondNitrogenOrganic ChemistrySolvationHydrogen BondingCrystallography X-RayBiochemistrySolventCrystallographychemistry.chemical_compoundchemistryCyclizationIntramolecular forceAmideMoleculeUreaComputer SimulationPhysical and Theoretical ChemistryAcetonitrileOrganicbiomolecular chemistry
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Synthesis of huge macrocycles using two calix[4]arenes as templates.

2005

Macrocycles with up to 100 atoms have been synthesised using two calix[4]arenes as templates: first, (3,5-dialkenyloxy)phenyl groups are attached to the wide rim of a calix[4]arene via urea links, then the alkenyl groups are connected via a metathesis reaction using a tetratosylurea calix[4]arene for their correct prearrangement and finally the urea functions are cleaved to detach the newly formed macrocycles.

Metals and AlloysGeneral ChemistryCatalysisSurfaces Coatings and FilmsElectronic Optical and Magnetic Materialschemistry.chemical_compoundTemplatechemistryPolymer chemistryMaterials ChemistryCeramics and CompositesSalt metathesis reactionUreaOrganic chemistryChemical communications (Cambridge, England)
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Self-Trapping of Magnetic Oscillation Modes in Landau Flux-Closure Structures

2005

We investigated the magnetodynamics in rectangular Permalloy platelets by means of time-resolved x-ray photoemission microscopy. 10 nm thick platelets of size 16 x 32 microm were excited by an oscillatory field along the short side of the sample with a fundamental frequency of 500 MHz and considerable contributions of higher harmonics. Under the influence of the oscillatory field, the Néel wall in the initial classical Landau pattern shifts away from the center, corresponding to an induced magnetic moment perpendicular to the exciting field. This phenomenon is explained by a self-trapping effect of the dominating spin-wave mode when the system is excited just below the resonance frequency. …

PermalloyPhysicsMagnetic momentMagnetic domainCondensed matter physicsSpin waveExcited stateHarmonicsddc:550PerpendicularGeneral Physics and AstronomyFundamental frequencyJPhysical Review Letters
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Heterodimeric capsules formed by tetratosyl and tetratolyl urea calix[4]arenes

2008

Predictions made by MD simulations for size, shape and guest inclusion of a heterodimer formed by a tetratosyl and a tetratolyl urea calix[4]arene and for its hydrogen bonding system have been entirely confirmed by a single crystal X-ray structure.

chemistry.chemical_compoundChemistryHydrogen bondPolymer chemistryUreaOrganic chemistryGeneral Materials ScienceGeneral ChemistryInclusion (mineral)Condensed Matter PhysicsSingle crystalCrystEngComm
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Experimental Investigations and ab Initio Studies on Hexacoordinated Complexes of Dichlorosilane

1998

Dichlorosilane, SiH2Cl2, forms two different kinds of coordination compounds with pyridine and 3-picoline:  the simple adduct trans-SiH2Cl2(L)2 and the ionic complex [SiH2(L)4]Cl2·4CHCl3 (L = pyridine, 3-picoline). The adducts trans-SiH2Cl2(py)2, 1, and trans-SiH2Cl2(3pic)2, 2, form directly from the reaction of bis(dichlorosilyl)methylamine, NMe(SiHCl2)2 with pyridine (py), and 3-picoline (3pic). Reaction of 1 with an excess of pyridine in chloroform yielded [SiH2(py)4]Cl2·4CHCl3, 3. The molecular and crystal structures of 1−3 were investigated by single-crystal X-ray diffraction. The Si atoms of all three compounds are hexacoordinated and lie on centers of inversion. The basic structural …

chemistry.chemical_classificationStereochemistryAb initioDichlorosilaneGeneral ChemistryCrystal structureTriclinic crystal systemBiochemistryCatalysisCoordination complexAdductchemistry.chemical_compoundCrystallographyColloid and Surface ChemistrychemistryPyridineMonoclinic crystal systemJournal of the American Chemical Society
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Multiple catenanes based on tetraloop derivatives of calix[4]arenes

2009

Abstract Four novel tetraarylurea calix[4]arenes ( 4a – d ) have been synthesized, substituted by ω-alkenyloxy residues in 3,5-positions of the arylurea residues. The eight alkenyl groups were pairwise connected by olefin metathesis and subsequent hydrogenation. The ring-closure reaction was carried out with heterodimers exclusively formed by 4 with a tetratosylurea calix[4]arene 1 , which serves as a template in this reaction step. The potential trans-cavity bridging is entirely suppressed in this way. Bis- and tetraloop calix[4]arenes cannot form dimers due to overlapping loops. However, they readily form heterodimers with open-chain tetraureas, as long as their urea residues can pass thr…

Cyclic compoundReaction stepStereochemistryDimerOrganic ChemistryCatenaneMetathesisBiochemistryTetraloopchemistry.chemical_compoundchemistryDrug DiscoveryCalixareneCyclophaneTetrahedron
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Calix[4]arene-Based Bis[2]catenanes: Synthesis and Chiral Resolution

2007

The exclusive formation of hydrogen-bonded dimers between tetraaryl and tetratosylurea calix[4]arenes has been used to prepare a series of ten "bisloop" tetraurea calix[4]arenes 3, in which adjacent phenylurea groups are covalently linked through alpha,omega-dioxyalkane chains. This dimerization with tetratosylurea 2 as template preorganizes the alkenyl residues of tetra(m-alkenyloxyphenyl) ureas 1 and enables their selective connection in high yield (up to 95 %) by olefin metathesis followed by hydrogenation. The "bisloop" calixarenes 3 also exclusively form heterodimers with 1. Thus, in a separated metathesis/hydrogenation sequence, a series of 14 cyclic bis[2]catenanes 4, in which two ca…

Models MolecularMagnetic Resonance SpectroscopyMolecular StructurebiologyChemistryStereochemistryOrganic ChemistryCatenaneCatenanesStereoisomerismSequence (biology)General ChemistryCrystallography X-Raybiology.organism_classificationMetathesisCatalysisChiral resolutionCrystallographyCovalent bondYield (chemistry)CalixareneTetraCalixarenesChemistry - A European Journal
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Molecules with New Topologies Derived from Hydrogen-Bonded Dimers of Tetraurea Calix[4]arenes

2008

Tetraurea calix[4]arenes 2 have been synthesized in which two adjacent aryl urea residues are connected to a loop by an aliphatic chain -O-(CH(2))(n)-O-. The remaining urea residues have a bulky 3,5-di-tert-butylphenyl residue and an omega-alkenyloxyphenyl residue. Since this bulky residue cannot pass through the loop, only one homodimer (22) is formed in apolar solvents, for steric reasons, in which the two alkenyl residues penetrate the two macrocyclic loops. Covalent connection of these alkenyl groups by olefin metathesis followed by hydrogenation creates compounds 3, which consist of molecules with hitherto unknown topology. Their molecular structure was confirmed by (1)H NMR spectrosco…

Models MolecularSteric effectsSpectrometry Mass Electrospray IonizationMagnetic Resonance SpectroscopyStereochemistryArylOrganic ChemistryHydrogen BondingGeneral ChemistryCatalysischemistry.chemical_compoundResidue (chemistry)PhenolschemistryCovalent bondCalixareneUreaProton NMRMoleculeCalixarenesDimerizationChemistry - A European Journal
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Narrow rim CMPO/adamantylcalix[4]arenes for the extraction of lanthanides and actinides

2011

Abstract Six p-(1-adamantyl)calix[4]arenes 7, 8 with four differently attached diphenyl-carbamoylmethylphosphine oxide (CMPO) functions at the narrow rim were synthesized. This series was extended by adamantylcalix[4]arenes with two CMPO and two ester, acid or (diethylphosphono)acetylamino groups. Structures of new compounds were proved by NMR, mass-spectrometry and a single-crystal X-ray analysis for the intermediate di-phthalimide 103. The extraction studies towards selected lanthanides and thorium showed that the ligands 7 surpassed the corresponding p-H, p-tert-butyl and p-tert-octyl analogues 3–5 in lanthanide extraction while thorium was extracted with the same or lesser extent. For t…

LanthanideLigandOrganic ChemistryExtraction (chemistry)OxideThoriumchemistry.chemical_elementActinideBiochemistrychemistry.chemical_compoundchemistryDrug DiscoveryCalixareneNuclear chemistryTetrahedron
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Synthesis and Structural Characterization of (1,4-Dihydropyrid-1-yl)aluminum Complexes

1999

The reaction between LiAlH(4) and pyridine, 4-methylpyridine, or 3,5-dimethylpyridine results in hydride transfer to the pyridine ring to give tetrakis(pyridine)lithium tetrakis(1,4-dihydropyrid-1-yl)aluminate(III), 1, tetrakis(4-methylpyridine)lithium tetrakis(1,4-dihydro-4-methylpyrid-1-yl)aluminate(III), 2, or tetrakis(3,5-dimethylpyridine)lithium tetrakis(3,5-dimethyl-1,4-dihydropyrid-1-yl)aluminate(III), 3, respectively. We claim that 1, instead of lithium tetrakis(1,4-dihydropyrid-1-yl)aluminate(III), is the compound which is known as Lansbury's reagent. Treatment of trimethylamine-alane, AlH(3).NMe(3), with pyridine yields tris(1,4-dihydropyrid-1-yl)(pyridine)aluminum, 4. It could be…

TrisHydrideAluminateInorganic chemistrychemistry.chemical_elementCrystal structureRing (chemistry)Medicinal chemistryInorganic Chemistrychemistry.chemical_compoundchemistryReagentPyridineLithiumPhysical and Theoretical ChemistryInorganic Chemistry
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ChemInform Abstract: Multiple Catenanes Based on Tetraloop Derivatives of Calix[4]arenes.

2009

StereochemistryChemistryCatenaneGeneral MedicineTetraloopChemInform
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Microscopic origin of the charge transfer in single crystals based on thiophene derivatives: A combined NEXAFS and density functional theory approach

2016

We have investigated the charge transfer mechanism in single crystals of DTBDT-TCNQ and DTBDT-F4TCNQ (where DTBDT is dithieno[2,3-d;2',3'-d'] benzo[1,2-b;4,5-b']dithiophene) using a combination of near-edge X-ray absorption spectroscopy (NEXAFS) and density functional theory calculations (DFT) including final state effects beyond the sudden state approximation. In particular, we find that a description that considers the partial screening of the electron-hole Coulomb correlation on a static level as well as the rearrangement of electronic density shows excellent agreement with experiment and allows to uncover the details of the charge transfer mechanism in DTBDT-TCNQ and DTBDT-F4 TCNQ, as w…

Absorption spectroscopyExtended X-ray absorption fine structureChemistryAnalytical chemistryGeneral Physics and Astronomy02 engineering and technology021001 nanoscience & nanotechnology01 natural sciencesMolecular physicsXANES0103 physical sciencesAtomCoulombDensity functional theoryAtomic numberPhysical and Theoretical Chemistry010306 general physics0210 nano-technologyElectronic densityThe Journal of Chemical Physics
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Two chloride ions as a template in the formation of a cyclic hexaurea.

2006

ChemistrymedicineGeneral ChemistryTemplate synthesisCombinatorial chemistryChlorideCatalysismedicine.drugIonAngewandte Chemie (International ed. in English)
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Synthesis and X-ray structure of amide-based macrocycles, catenanes and pretzelane

2001

The syntheses and crystal structure studies of amide-based catenanes derived from m-phenylene diacrylic acid and 5-acetoxy isophthalic acid (17% and 3% yield of 4a and 4b resp.) and octalactam macrocycles (21% yield of 3) are described. Hydrogen bonding patterns play a key role in the formation of the different conformations of octalactam 3. The crystal structures of 3 reveal a number of hydrogen-bonding interactions between the macrocycle and two different solvent molecules, which are presumably responsible for the different conformations. Furthermore, we report the X-ray structure of a catenane, which was converted into a “pretzelane” by bridging two phenolic hydroxy groups with a p-xylyl…

Isophthalic acidSolventchemistry.chemical_compoundchemistryHydrogen bondStereochemistryAmideOrganic ChemistryCatenaneSupramolecular chemistryMoleculeCrystal structurePhysical and Theoretical Chemistry
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Crystal structure of t-Butylcalix[8]arene octamethyl ether

2002

Abstract The title compound 1a crystallized with a molecule of chloroform in a triclinic lattice, space group P-1, with a=16.5215(19) A, b=17.4181(19) A, c=18.7403(18) A, α=78.328(8)°, β=64.210(8)°, γ=87.863(9)°, Z=2. The molecule assumes a not yet observed conformation with approximate (not crystallographic) C4V-symmetry with the inclusion of one molecule of chloroform in the molecular cavity. Layers of molecules are packed in alternating order in the crystal lattice.

ChloroformChemistryOrganic ChemistryEtherGeneral ChemistryCrystal structureTriclinic crystal systemInorganic Chemistrychemistry.chemical_compoundCrystallographyLattice (order)CalixareneMaterials ChemistryMoleculeJournal of Supramolecular Chemistry
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5,11,17,23-Tetranitro-25,26,27,28-tetrapentyloxycalix[4]arene

2005

The mol­ecule of the title compound, C48H60N4O12, is located on a crystallographic twofold rotation axis. It is found in the typical pinched cone conformation. The dihedral angles between the reference plane (defined by the C atoms of the methyl­ene bridges) and the benzene rings are 83.33 (6) and 141.61 (5)°.

Reference planeCone conformationchemistry.chemical_compoundCrystallographyChemistryGeneral Materials ScienceGeneral ChemistryDihedral angleCondensed Matter PhysicsRotationBenzeneActa Crystallographica Section E Structure Reports Online
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3-Oxa-6,8-diaza-1,2:4,5-dibenzocycloocta-1,4-dien-7-one: a three-dimensional network assembled by hydrogen-bonding, pi-pi and edge-to-face interactio…

2003

The title compound, C(13)H(10)N(2)O(2), is the first structure in which the urea moiety is incorporated into an eight-membered ring. Two molecules are found in the asymmetric unit, which are almost identical in their conformation and their hydrogen-bond pattern. The carbonyl O atom acts as a double acceptor for the NH groups of two adjacent molecules. In this way, infinite tapes are formed, which are connected via pi-pi and edge-to-face interactions in the second and third dimension. This hierarchical order of interactions is confirmed by molecular mechanics calculations. Force-field and semi-empirical calculations for a single molecule did not find the envelope conformation present in the …

HydrogenHydrogen bondStereochemistryDimerchemistry.chemical_elementGeneral MedicineCrystal structureAcceptorGeneral Biochemistry Genetics and Molecular BiologyCrystalchemistry.chemical_compoundchemistryMoietyMoleculeActa crystallographica. Section C, Crystal structure communications
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Halogen exchange and expulsion: ligand stabilized dihalogen silicon dications

2000

The first ligand stabilized SiCl22+ dications were synthesized using N-methylimidazole as co-ordinating ligand. The compounds SiCl4, SiBr2Cl2, and SiH2Cl2 form six-co-ordinated dicationic compounds of almost octahedral symmetry with similar structures which were investigated by single crystal X-ray analysis and density functional calculations. The structures exhibit particularly short dative Si–N bonds of about 1.90 A. Complexes crystallized from the same solvent are isostructural. A different solvent, though, leads to geometrical variations. It was also discovered that the halogen exchange process among mixed silicon tetrahalides occurs under much milder conditions than previously thought …

SolventCrystallographySiliconchemistryLigandOctahedral symmetryHalogenInorganic chemistrychemistry.chemical_elementGeneral ChemistryIsostructuralSingle crystalCatalysisJournal of the Chemical Society, Dalton Transactions
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Macrocyclic oligoureas with xanthene and diphenyl ether units

2009

Two cyclic oligoureas with 64- and 80-membered rings in which two sets of three or four rigid xanthene (X) units are connected via flexible diphenyl ether (D) units were synthesized by a stepwise fragment condensation. The compounds were characterized by (1)H NMR and ESI mass spectrometry. The structure of the cyclic octamer (XXXDXXXD) was additionally confirmed by single crystal X-ray analysis. The molecule assumes a strongly folded conformation with distorted C(2)-symmetry, stabilized by intramolecular hydrogen bonds. Surprisingly, intermolecular hydrogen bonds between the macrocycles were not observed. (1)H NMR spectra suggest a C(2) symmetrical conformation of the octamer in solution al…

Models MolecularXantheneMacrocyclic CompoundsMagnetic Resonance SpectroscopyPolymersHydrogen bondChemistryStereochemistryPhenyl EthersOrganic ChemistryDiphenyl etherIntermolecular forceMolecular ConformationCrystallography X-RayBiochemistryCrystallographychemistry.chemical_compoundXanthenesIntramolecular forceProton NMRMoleculeHistone octamerPhysical and Theoretical ChemistryOrganic & Biomolecular Chemistry
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Selective access to either a doubly boron-doped tetrabenzopentacene or an oxadiborepin from the same precursor

2019

Depending on the solvent, a brominated arylborane gave the multiple helicene B2-TBPA (pyridine) or the oxadiborepin ODBE (THF) after intramolecular Yamamoto coupling.

chemistry.chemical_classificationAnthraceneReaction mechanism010405 organic chemistrychemistry.chemical_elementGeneral ChemistryElectron acceptor010402 general chemistry01 natural sciences0104 chemical sciencesChemistrychemistry.chemical_compoundCrystallographychemistryIntramolecular forceYield (chemistry)PyridineMoietyBoronChemical Science
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Conformational properties of cyanomethoxy calix[4]arenes.

2005

O-Alkylation of the dinitro calix[4]arene 2, easily available by selective ipso-nitration of the di-cyanomethyl ether 1, with allylbromide (DMF/Cs2CO3) gave tetraethers 3 and 4 with anti- and syn-orientations of the two allyl ether residues. The two possible stereoisomers of 3 in the partial cone and 1,2-alternate conformation exist as an equilibrium mixture which could be quantitatively analysed by 1H NMR spectroscopy. The temperature dependence of this equilibrium leads to ΔH0 = − 7.6 to −9.7 kJ mol−1 in different solvents (tetrachloroethane, benzene, dimethylsulfoxide). Since 3(1,2-alt) could be obtained in pure form, its isomerisation to the equilibrium mixture with 3(paco) could be fol…

1h nmr spectroscopyChemistryOrganic ChemistryEtherActivation energyKinetic energyBiochemistryTetrachloroethanechemistry.chemical_compoundOrganic chemistryPhysical chemistryPhysical and Theoretical ChemistryBenzeneSingle crystalIsomerizationOrganicbiomolecular chemistry
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Crystalline self-assembly induced by aromatic edge-to-face interactions: the crystal structure of 2,6,6,10-tetrabenzyl-2,10-diaza-6-azonia[11]paracyc…

2002

The crystal structure of 2,6,6,10-tetrabenzyl-2,10-diaza-6-azonia[11]paracyclophane bromide reveals several intermolecular aromatic edge-to-face interactions which are important in the three-dimensional growing of the crystalline structure. Molecular dynamics and semiempirical studies indicate that the conformer found in the crystal is not the most stable in solution confirming the important role that edge-to-face interactions play in the structural arrangement found in the solid state.

ChemistryOrganic ChemistryIntermolecular forceSolid-stateCrystal structureBiochemistryCrystalMolecular dynamicschemistry.chemical_compoundCrystallographyBromideDrug DiscoverySelf-assemblyConformational isomerismTetrahedron
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Tetra-CMPO-derivatives of calix[4]arenes fixed in the 1,3-alternate conformation

2010

Calix[4]arene derivatives fixed in the 1,3-alternate conformation and substituted at one side by four carbamoylmethylphosphine oxide (CMPO) residues were synthesised. Two CMPO groups are directly attached to the wide rim, while the second pair is bound to the narrow rim via a tri- or tetramethylene spacer. Similar compounds, in which two CMPO groups at the wide rim are combined with two picolinamide groups or two ionisable carboxylic groups at the narrow rim, were also prepared. Some of these calixarene derivatives were studied as extractants for lanthanides (La3+, Eu3+, Yb3+) and thorium (Th4+) from acidic solution into methylene chloride. For selected samples, stability constants in metha…

LanthanidebiologyInorganic chemistryGeneral ChemistryCrystal structurebiology.organism_classificationChloridechemistry.chemical_compoundchemistryCalixarenePolymer chemistrymedicineTetraTitrationMethanolMethylenemedicine.drugSupramolecular Chemistry
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Hydrogen-bonded dimers of a thiacalixarene substituted by carbamoylmethylphosphineoxide groups at the wide rim.

2006

A thiacalix[4]arene derivative bearing four carbamoylmethylphosphineoxide groups at the wide rim forms hydrogen-bonded, dimeric capsules with S8 symmetry in the crystalline state and in apolar solvents, where the inclusion of cationic guests could be proved by 1H NMR and ESI mass spectra.

HydrogenStereochemistryMetals and AlloysCationic polymerizationchemistry.chemical_elementGeneral ChemistryCatalysisSurfaces Coatings and FilmsElectronic Optical and Magnetic Materialschemistry.chemical_compoundCrystallographychemistryMaterials ChemistryCeramics and CompositesProton NMRMass spectrumThiacalixareneDerivative (chemistry)Chemical communications (Cambridge, England)
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26,28-Diallyloxy-5,11,17,23-tetra-tert-butyl-25,27-bis(cyanomethoxy)calix[4]arene in the partial cone conformation

2006

The title compound, C54H66N2O4, crystallizes with two mol­ecules in the asymmetric unit. Both adopt the typical partial cone conformation which was also found for 26,28-diall­yloxy-5,17-di-tert-butyl-25,27-bis­(cyano­meth­oxy)-11,23-dinitrocalix[4]arene [Danila, Bohmer & Bolte (2005). Org. Biomol. Chem. 3, 3508–3513]. The crystal structure of the title compound in the 1,2-alternate conformation has been determined recently [Danila, Bohmer & Bolte (2005). Org. Biomol. Chem. 3, 3508–3513].

Tert butylchemistry.chemical_compoundCone conformationchemistrybiologyStereochemistryTetraGeneral Materials ScienceGeneral ChemistryMeth-Crystal structureCondensed Matter Physicsbiology.organism_classificationActa Crystallographica Section E Structure Reports Online
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Crystal growth of new charge-transfer salts based on π-conjugated donor molecules

2016

Abstract New charge transfer crystals of π-conjugated, aromatic molecules (phenanthrene and picene) as donors were obtained by physical vapor transport. The melting behavior, optimization of crystal growth and the crystal structure are reported for charge transfer salts with (fluorinated) tetracyanoquinodimethane (TCNQ-Fx, x=0, 2, 4), which was used as acceptor material. The crystal structures were determined by single-crystal X-ray diffraction. Growth conditions for different vapor pressures in closed ampules were applied and the effect of these starting conditions for crystal size and quality is reported. The process of charge transfer was investigated by geometrical analysis of the cryst…

Materials scienceInfrared spectroscopyCrystal growth02 engineering and technologyCrystal structureCondensed Matter - Soft Condensed Matter010402 general chemistry021001 nanoscience & nanotechnologyCondensed Matter Physics01 natural sciencesTetracyanoquinodimethaneAcceptor0104 chemical sciencesElectronic Optical and Magnetic MaterialsCrystalchemistry.chemical_compoundchemistryPicenePhysics - Chemical PhysicsMoleculePhysical chemistryElectrical and Electronic Engineering0210 nano-technologyPhysica B: Condensed Matter
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Zwei Chloridionen als Templat bei der Bildung eines cyclischen Hexaharnstoff-Moleküls

2006

ChemistryGeneral MedicineAngewandte Chemie
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Redetermination of 5,11,17,23-tetra-tert-butyl-25,27-di(ethoxycarbonylmethoxy)-26,28-dihydroxycalix[4]arene chloroform disolvate at low temperature

2003

The title compound, C52H68O8·2CHCl3, previously reported by Ferguson et al. [Supramol. Chem. (1996), 7, 223–228], has been rerefined against new intensity data. The geometric parameters are comparable, as far as they are available. However, the results of the present structure determination are of significantly higher precision.

Tert butylbiologyStereochemistryChemistryAlkoxy groupTetraGeneral Materials ScienceGeneral ChemistryCondensed Matter Physicsbiology.organism_classificationMedicinal chemistryActa Crystallographica Section E Structure Reports Online
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5,11,17,23-Tetra-tert-butyl-25,26,27,28-tetrapentoxycalix[4]arene

2005

The mol­ecule of the title compound, C64H96O4, adopts the typical pinched-cone conformation. The dihedral angles between the reference plane (defined by the C atoms of the methyl­ene bridges) and the benzene rings are 86.88 (4), 136.64 (5), 87.22 (4) and 133.99 (4)°.

Tert butylReference planechemistry.chemical_compoundCrystallographybiologyChemistryTetraGeneral Materials ScienceGeneral ChemistryDihedral angleCondensed Matter Physicsbiology.organism_classificationBenzeneActa Crystallographica Section E Structure Reports Online
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Macrocyclic hexaureas: synthesis, conformation, and anion binding.

2009

Varied flexibility: Cyclic oligoureas are formed by using anions as templates. Linking of six xanthene and/or diphenyl ether fragments by urea groups leads to the formation of five macrocyclic compounds with a 48-membered ring with variable flexibility (see picture). Their interaction with anions shows a strong influence of acetate and chloride ions on the cyclization from four precursor molecules. Five macrocylic compounds XXXXXX, XXDXXD, XDXDXD, XDDXDD, and DDDDDD with 48-membered rings, in which six xanthene and/or diphenyl ether fragments are linked through six urea (-NH-C(O)-NH-) groups, have been synthesized. In the cyclization step, a linear diamine was allowed to react with the appr…

XantheneChemistryHydrogen bondStereochemistryOrganic ChemistryDiphenyl etherGeneral ChemistryCondensation reactionMedicinal chemistryCatalysischemistry.chemical_compoundIntramolecular forceDiamineMoleculeAnion bindingChemistry (Weinheim an der Bergstrasse, Germany)
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Unusual conformations of 1,3-dialkoxythiacalix[4]arenes in the solid state

2006

The structures of three syn-1,3-dialkoxythiacalix[4]arenes with unusual conformations in the solid state are reported. The pinched cone conformation of syn-2 2 ,4 2 -dihydroxy-1 2 ,3 2 -bis-(prop-2-enyloxy)thiacalix[4]arene, C 30 H 24 O 4 S 4 , (3a), is stabilized by two intramolecular hydrogen bonds, remarkably formed from both OH groups to the same ether O atom. In syn-22,42-dihydroxy-1 5 ,2 5 ,3 5 ,4 5 -tetranitro-12,32-bis(prop-2-enyloxy)thiacalix[4]arene acetone disolvate, C 30 H 20 N 4 O 12 S 4 ·-2C 3 H 6 O, (3b1), the molecule is found in the 1,3-alternate conformation. The crystallographic C2 symmetry is due to a twofold rotation axis running through the centre of the calixarene rin…

Molecular StructureSulfur CompoundsStereochemistryHydrogen bondMolecular ConformationHydrogen BondingEtherGeneral MedicineCrystal structureCrystallography X-RayAcceptorGeneral Biochemistry Genetics and Molecular BiologySolventCrystallographychemistry.chemical_compoundchemistryIntramolecular forceCalixareneMoleculeCalixarenesEthersActa Crystallographica Section C Crystal Structure Communications
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Dimeric Capsules Formed by Tetra-CMPO Derivatives of (Thia)Calix[4]arenes

2010

Thiacalix[4]arene 2, calix[4]arene 3 a and its tetraether fixed in the cone conformation 3 b form homo- and heterodimeric capsules in apolar solvents, which are held together by a seam of NH⋅⋅⋅O=P hydrogen bonds between carbamoylmethyl phospine oxide functions attached to their wide rim. Their internal volume of ∼370 A3 requires the inclusion of a suitable guest. Although neutral molecules such as adamantane (derivatives) or tetraethylammonium cations form kinetically stable complexes (1H- and 31P-time scale), the included solvent is rapidly exchanged. The internal mobility of the included tetraethylammonium cation is distinctly higher (ΔG=42.5 and 49.7 kJ mol−1 for 3 a and 3 b) than that f…

TetraethylammoniumbiologyHydrogen bondAdamantaneOrganic ChemistryCationic polymerizationGeneral Chemistrybiology.organism_classificationBiochemistrySolventchemistry.chemical_compoundchemistryCalixarenePolymer chemistryMoleculeTetraChemistry - An Asian Journal
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1,3-Alternate calix[4]arenes, selectively functionalized by amino groups

2004

General strategies are described to synthesize calix[4]arenes which are fixed in the 1,3-alternate conformation and substituted selectively by amino groups. These derivatives are useful starting materials for the attachment of various groups via amide bonds, as demonstrated by several examples, but may be converted also to ureas, imides or azomethines. Four amino groups may be attached to the narrow rim via(several) methylene groups as spacer by O-alkylation with omega-bromophthalimides or omega-bromonitriles. From the resulting tetraethers the amino functions are obtained by cleavage with hydrazine or by hydrolysis, allowing a selective functionalisation of both sides of the molecule (phen…

PhthalimidesChemistryStereochemistryOrganic ChemistryCleavage (embryo)BiochemistryHydrolysischemistry.chemical_compoundYield (chemistry)Proton NMRNitroMoleculePhysical and Theoretical ChemistryMethyleneOrg. Biomol. Chem.
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Cyclic triureas—synthesis, crystal structures and properties

2008

The synthesis of 24-membered macrocycles is described, in which rigid xanthene units (X) and/or diphenyl ether units (D) as flexible analogues are linked via urea groups. All four possible combinations (XXX, XXD, XDD, DDD) have been obtained with yields of 40-72% for the cyclisation step. In two cases, the respective cyclic hexamers (XXDXXD, XXXXXX) were also isolated. Two compounds have been characterised by a single crystal X-ray analysis of the free triurea (XXD, XDD) and one example (DDD) by its complex with tetrabutylammonium chloride. It shows the chloride anion in the centre of the macrocycle, held by six NH...Cl- hydrogen bonds. The interaction with various other anions has been stu…

Models MolecularAcetonitrilesMacrocyclic CompoundsInorganic chemistryCrystallography X-RayBiochemistryChloridechemistry.chemical_compoundBromidemedicineUreaPhysical and Theoretical ChemistryAcetonitrileXantheneMolecular StructureHydrogen bondOrganic ChemistrySolvationHydrogen BondingQuaternary Ammonium CompoundsSolventCrystallographyXantheneschemistryCyclizationIntramolecular forceSpectrophotometry UltravioletChloroformCrystallizationmedicine.drugOrganic & Biomolecular Chemistry
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A macrocyclic diurea derived from diphenylether

2010

Abstract A new 16-membered cyclic diurea was synthesized and tested as potential receptor for fluoride. 1 H and 19 F NMR spectroscopy revealed an unexpected deprotonation of both urea groups after initial 1:1 binding. A single crystal X-ray structure shows bifurcated hydrogen bonds to two DMSO molecules.

chemistry.chemical_compoundCrystallographyDeprotonationchemistryHydrogen bondOrganic ChemistryDrug DiscoveryUreaMoleculeNuclear magnetic resonance spectroscopyBiochemistrySingle crystalFluorideTetrahedron Letters
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Supramolecular structures formed by calix[8]arene derivatives.

2003

Octamethoxy calix[8]arenes substituted in the para position by amide, urea, and imide functions were synthesized from the octamethyl ether of tert-butylcalix[8]arene by ipso nitration, reduction, and acylation. Scanning force microscopy of spin coated samples on graphite suggests that these derivatives self-organize into tubular nanorods via hydrogen bonds between p-amide functions. A single-crystal X-ray structure reveals a centrosymmetric conformation for the octanitro derivative. [structure: see text]

ChemistryStereochemistryHydrogen bondOrganic ChemistrySupramolecular chemistryEtherBiochemistryAcylationchemistry.chemical_compoundNitrationAmidePolymer chemistryNanorodPhysical and Theoretical ChemistryImideOrganic letters
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CCDC 1922191: Experimental Crystal Structure Determination

2019

Related Article: Julian Radtke, Kai Schickedanz, Marcel Bamberg, Luigi Menduti, Dieter Schollmeyer, Michael Bolte, Hans-Wolfram Lerner, Matthias Wagner|2019|Chemical Science|10|9017|doi:10.1039/C9SC03115D

naphtho[1'8':234][1]benzoborinino[18-cd]naphtho[1'8':456]borinino[321-jk][213]benzoxadiborepineSpace GroupCrystallographyCrystal SystemCrystal StructureCell ParametersExperimental 3D Coordinates
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CCDC 1448360: Experimental Crystal Structure Determination

2016

Related Article: Antonia Morherr, Sebastian Witt, Alisa Chernenkaya, Jan-Peter Bäcker, Gerd Schönhense, Michael Bolte, Cornelius Krellner|2016|Physica B: Condensed Matter(Amsterdam)|496|98|doi:10.1016/j.physb.2016.05.023

Space GroupCrystallographyCrystal SystemCrystal StructureCell ParametersExperimental 3D Coordinates22'-(25-difluorocyclohexa-25-diene-14-diylidene)dimalononitrile phenanthrene
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CCDC 1448362: Experimental Crystal Structure Determination

2016

Related Article: Antonia Morherr, Sebastian Witt, Alisa Chernenkaya, Jan-Peter Bäcker, Gerd Schönhense, Michael Bolte, Cornelius Krellner|2016|Physica B: Condensed Matter(Amsterdam)|496|98|doi:10.1016/j.physb.2016.05.023

Space GroupCrystallographyCrystal SystemCrystal StructureCell Parameters22'-cyclohexa-25-diene-14-diylidenedimalononitrile piceneExperimental 3D Coordinates
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CCDC 1448363: Experimental Crystal Structure Determination

2016

Related Article: Antonia Morherr, Sebastian Witt, Alisa Chernenkaya, Jan-Peter Bäcker, Gerd Schönhense, Michael Bolte, Cornelius Krellner|2016|Physica B: Condensed Matter(Amsterdam)|496|98|doi:10.1016/j.physb.2016.05.023

Space GroupCrystallography22'-(25-difluorocyclohexa-25-diene-14-diylidene)dimalononitrile piceneCrystal SystemCrystal StructureCell ParametersExperimental 3D Coordinates
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CCDC 1922189: Experimental Crystal Structure Determination

2019

Related Article: Julian Radtke, Kai Schickedanz, Marcel Bamberg, Luigi Menduti, Dieter Schollmeyer, Michael Bolte, Hans-Wolfram Lerner, Matthias Wagner|2019|Chemical Science|10|9017|doi:10.1039/C9SC03115D

Space GroupCrystallographyCrystal SystemCrystal Structure16-dibromo-510-bis(8-iodonaphthalen-1-yl)-510-dihydroboranthreneCell ParametersExperimental 3D Coordinates
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CCDC 1922192: Experimental Crystal Structure Determination

2019

Related Article: Julian Radtke, Kai Schickedanz, Marcel Bamberg, Luigi Menduti, Dieter Schollmeyer, Michael Bolte, Hans-Wolfram Lerner, Matthias Wagner|2019|Chemical Science|10|9017|doi:10.1039/C9SC03115D

Space GroupCrystallographyCrystal SystemCrystal StructureCell Parameters(8-[3-(naphthalen-1-yl)phenyl]-7H-benzo[e]naphtho[18-bc]borinin-7-olato)-(phthalazin-2-ium)-boron benzene solvateExperimental 3D Coordinates
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CCDC 1922190: Experimental Crystal Structure Determination

2019

Related Article: Julian Radtke, Kai Schickedanz, Marcel Bamberg, Luigi Menduti, Dieter Schollmeyer, Michael Bolte, Hans-Wolfram Lerner, Matthias Wagner|2019|Chemical Science|10|9017|doi:10.1039/C9SC03115D

Space GroupCrystallographyCrystal SystemCrystal StructureCell Parametersbisnaphtho[1'8':456]borinino[321-de:3'2'1'-kl]boranthreneExperimental 3D Coordinates
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CCDC 1448361: Experimental Crystal Structure Determination

2016

Related Article: Antonia Morherr, Sebastian Witt, Alisa Chernenkaya, Jan-Peter Bäcker, Gerd Schönhense, Michael Bolte, Cornelius Krellner|2016|Physica B: Condensed Matter(Amsterdam)|496|98|doi:10.1016/j.physb.2016.05.023

Space GroupCrystallographyCrystal SystemCrystal StructureCell Parameters22'-(2356-tetrafluorocyclohexa-25-diene-14-diylidene)dimalononitrile phenanthreneExperimental 3D Coordinates
researchProduct

CCDC 1922188: Experimental Crystal Structure Determination

2019

Related Article: Julian Radtke, Kai Schickedanz, Marcel Bamberg, Luigi Menduti, Dieter Schollmeyer, Michael Bolte, Hans-Wolfram Lerner, Matthias Wagner|2019|Chemical Science|10|9017|doi:10.1039/C9SC03115D

Space GroupCrystallographyCrystal SystemCrystal StructureCell Parameters510-bis(8-bromonaphthalen-1-yl)-510-dihydroboranthrene benzene solvateExperimental 3D Coordinates
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