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  • Macrocycles  (19)
  • Supramolecular chemistry  (12)
  • Chirality  (5)
  • 1
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 123 (1990), S. 1097-1103 
    ISSN: 0009-2940
    Keywords: Bond formation, C-C ; Iron complexes ; Macrocycles ; Molecular tweezers ; Naphthalenophane ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Preorganized Bis-ethynes: Molecular π-Tweezers?1,8-Bis[(arylethynylphenyl)]naphthalenes of type V (e.g. 10, 11) and 1,8-bis[(arylethenylphenyl)]naphthalenes (6, 6a, 7, 7a) were synthesized for the first time. In contrast to the known 1,8-bis(arylethynyl)naphthalenes VI their “stereologs” 10 and 11 are thermally stabile. Yet they react with pentacarbonyliron to yield dinuclear transition metal complexes of the type 12, 13, i.e. a strained cyclophane macrocycle is formed by C-C bond formation. The X-ray analysis of the di-tert-butyl compound 11 shows that the peri substituents diverge, but with increasing distance from the naphthalene skeleton one of the arylethynyl units is bent to the opposite direction (Figure 2). The question whether the new molecular skeleton V can be viewed as molecular tweezers is discussed: as the hydrocarbons react irreversibly with transition metal carbonyls, they may rather be taken as “tweezers for single use”.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
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  • 2
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 125 (1992), S. 1687-1695 
    ISSN: 0009-2940
    Keywords: Host-Guest chemistry ; Inclusion compounds ; Macropolycyclic compounds ; Heterocyclic compounds ; Supramolecular chemistry ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Multiple-Bridged TriphenylmethanesUp to fourfold-bridged macrocyclic compounds bearing triphenylmethane units which form a large molecular cavity were prepared for the first time. The macrobicyclus 4 crystallizes from acetonitrile as 1:1 adduct and from phenylacetonitrile as 1:3 adduct with the respective solvent. The X-ray structures of these complexes are compared with the related 1:5 adduct of 13 with benzene.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
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  • 3
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 125 (1992), S. 2523-2531 
    ISSN: 0009-2940
    Keywords: Carbocycles ; Large rings ; Macrocycles ; [2n]Metacyclophanes ; Müller-Röscheisen reaction ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Many-Membered and Donor-Substituted Hydrocarbon RingsThe preparation of large rings 2 of the [2n]metacyclophane type by the Müller-Röscheisen method is described. Yields of cyclic products, potential ligand or host character and ring size can be controlled by intra- and extraannular OCH3 groups. The 40-membered macrocyclus 24 containing eight substituted benzene rings is the largest ring compound of this series isolated so far in pure form. Large substituents OR in position 2 of the starting bis(bromomethyl) compounds lead to higher ring member numbers. The new macrocyclic compounds, with the exception of the “dimer” 7, are all conformationally flexible according to 1H-NMR spectra. X-ray structural analyses were performed of the macrocycles 10, 13, 17, and 18; the inclusion of solvent molecules is proven.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
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  • 4
    ISSN: 0009-2940
    Keywords: Carbocycles ; Homocalixarenes ; Calixarenes, Homo- ; Large rings ; Macrocycles ; [2n]Metacyclophanes ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: all-Homocalixarenes: Carbocyclic Host Compounds with Intra- and Extraannular Ligand ArmsMethoxy-substituted [2n]metacyclophanes 1-10, obtained by Müller-Röscheisen cyclization, are converted into all-homocalixarenes 11-20 with free phenolic hydroxy functions. The well-soluble cyclic pentamer 11 and octamer 14 with endo-acidic host properties are investigated with regard to guest binding. They exhibit selectivity towards alkaline earth metal ions (Ba2+) in liquid/liquid extraction studies. Some of the macrocyclic oligophenols are transformed into homocalixarenes 21-25 with intra- or extraannular oxapropionate groups. The diester 22 and the tetraester 23 are converted into carbocycles 26 and 27 with two and four free oxapropionic acid groups. Complexation properties of the oligoesters in extraction studies and log K values in water are reported. X-ray structural analyses were performed of the [6]-, [8]- and [4]- homocalixarenes 9 and 21, 14 and 23; the inclusion of solvent molecules is proven.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
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  • 5
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 126 (1993), S. 1161-1169 
    ISSN: 0009-2940
    Keywords: Azobenzene units ; Dendrimer ; Divergent synthesis ; Solvent inclusion ; Supramolecular chemistry ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Dendrimers with bulky repeating units containing up to 43 benzene rings (in 9) have been obtained by using a repetitive divergent synthetic strategy (three generations). The new functional dendrimer 13 containing six azobenzene units at the periphery was synthesized allowing a reversible switching of the shape and size of the molecule upon irradiation. An X-ray structure analysis of the dendritic molecule 3a shows the inclusion of acetonitrile.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
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  • 6
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 124 (1991), S. 671-672 
    ISSN: 0009-2940
    Keywords: Azines ; Bis(azines) ; Macrocycles ; Tetraazapolyenes ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The new macrocyclic bis(azine) 2 forming yellow microcrystals has been prepared in 72% yield by treating the diketone 1 with hydrazine hydrate under high-dilution conditions. In contrast to the UV/Vis spectrum of the “open-chain” azine 4, that of 2 shows characteristic features of a polyene chromophore containing (Z)-configurated double bonds.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
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  • 7
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 125 (1992), S. 1873-1880 
    ISSN: 0009-2940
    Keywords: Complex formation ; Endoreceptors ; Macrobicyclic ligands ; Phenanthroline derivatives ; Supramolecular chemistry ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Macrobicyclic Endoreceptors: Synthesis, Crystal Structure, and Inclusion of Organic GuestsThe macrobicyclic ligand 2 is synthesized in a one-step cyclization procedure. According to an X-ray structure analysis three dichloromethane guest molecules are included inside the cavity, whereas water and methanol are found outside the cavity. The rigid endo preorganization of the nitrogen donors allows the complexation of three 2,9-disubstituted 1,10-phenanthrolines inside the cavity.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
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  • 8
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 126 (1993), S. 1003-1009 
    ISSN: 0009-2940
    Keywords: Diamine ; Host-guest chemistry ; Macrocycle ; Supramolecular chemistry ; Receptor molecule, synthetic ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Tailor-Made Host for Piperazine and Related AminesThe 38-membered bis-catechol 4b is obtained by cyclisation of the diacyl dichloride 3c with the diamine 2b in 45% yield, whereas a 68-membered octalactam 7 is formed under similar conditions from 5 and 1b. Bis-catechol 4b is a selective host compound for piperazine (8) and the structurally related diamine 9. Association constants for the 1:1 complexes have been measured by 1H-NMR titration experiments. A nucleobase guest (pterine, 24) was extracted into a hydrochloric acid phase by complex formation with the host 4b. The results are compared with solubility and transport experiments obtained by use of analogous macrobicyclic tris-catechol hosts.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
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  • 9
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 126 (1993), S. 1713-1721 
    ISSN: 0009-2940
    Keywords: Concave molecules ; Cyclophanes ; High-dilution principle ; Macrocycles ; Spheriphanes ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Concave MacroheterocyclesMacrocyclic compounds of the general type 2 having a spherical shape and a molecular cavity have been synthesized. A „fold and paste“-type cyclization step generates the macroheterocycles 4, 10, 11, 14, and 21. Since this approach is difficult to apply for O-substituted derivatives, the „spheriphane“ 24 was synthesized by intermolecular cyclizaiton. The X-ray structure analysis of 11 shows intermolecular interactions („dimer formation“) in the crystal.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
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  • 10
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 126 (1993), S. 1723-1732 
    ISSN: 0009-2940
    Keywords: Cyclohexanes ; Cyclohexanones ; Cyclophanes ; Macrocycles ; Paracyclophanes ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: On the Way to Macrocyclic para-PhenylenesStrategies are presented to synthesize the hitherto unknown [On]Paracyclophanes 1. Open chain belt-type molecules based on 1,4-connected carbocyclic six-membered rings were prepared. Functionalization of the outer rings in 4-position is the prerequisite for cyclization or lengthening of the molecular belts. In order to obtain the macrocyclic target molecules 1, well preorganized cis-isomers of 1,4-disubstituted cyclohexanes were prepared. X-ray structural analyses reveal the static stereochemistry of the intermediates 8, 9, 17, 18, and 24. The macrocyclic hydrocarbon 29 containing five cyclohexylidene units was detected.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
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