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  • Template synthesis  (5)
  • Helical molecules  (4)
  • Mechanical bond  (4)
  • 1
    Electronic Resource
    Electronic Resource
    Templat-Synthese makrobicyclischer Großhohlräume vom Tris(bipyridin)-Typ (1989)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 122 (1989), S. 1725-1727 
    Details
    ISSN: 0009-2940
    Keywords: Cryptands ; Macrobicyclic ligands ; Template synthesis ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Template Synthesis of Macrobicyclic Large Cavities of the Tris-(bipyridine)-TypeThe synthesis of the ligands 2 and 3 has been performed in a one-step procedure starting with the triamines 11 and 12 and 5,5′-bis(bromomethyl)-2,2′-bipyridine (6). The new macrobicyclic compounds were isolated and characterized as their sodium complexes. Dynamic 1H-NMR investigations reveal the conformational flexibility of the complex 2 · Na⊕.
    Notes: Die Liganden 2 und 3 wurden in einer Eintopf-Synthese ausgehend von den Triaminen 11 und 12 sowie 5,5′-Bis(brommethyl-2,2′-bipyridin (6) erhalten und als Natrium-Komplexe isoliert und charakterisiert. Die dynamische 1H-NMR-Spektroskopie des Komplexes 2 · Na⊕ belegt seine konformative Beweglichkeit.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19891220920
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  • 2
    Electronic Resource
    Electronic Resource
    Helicale und planarchirale Pyridinophane - Neue Synthesemethodik und Struktur-Chiroptik-Beziehungen (1989)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 122 (1989), S. 347-355 
    Details
    ISSN: 0009-2940
    Keywords: Circular dichroism ; Helical molecules ; [2.2]Metacyclophanes ; Oxa[2.2]metacyclophane ; [2.2]Pyridinophanes ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Helical and Planar-chiral Pyridinophanes - A New Synthesis and Structure/Chiroptic RelationshipsA new two-step synthesis for the strained helical oxa[2.2]phanes 1-5 and for a systematic series of novel structural isomeric (2,4)-pyridinophanes (6-10) is presented. The energy barriers for ring inversion of some intermediate [3.2]phanes and the kinetics of racemization of the [2.2]phanes are determined. Separation and enrichment of enantiomers is achieved by HPLC on cellulose tris(3,5-dimethylphenyl)carbamate and poly(triphenylmethylmethacrylate), resp. The circular dichroism curves of the isomers are compared with those of the corresponding protonated pyridinium compounds. The influence of the chromophor orientation on the circular dichroism is discussed.
    Notes: Eine neue Zweistufensynthese zu den stark ringgespannten, helicalen Oxa[2.2]phanen 1-5 und eine systematische Reihe neuer strukturisomerer (2,4)-Pyridinophane (6-10) werden vorgestellt. Die Energiebarrieren für die Ringinversion der intermediären [3.2]Phane und die Racemisierungskinetik der [2.2]Phane werden gemessen. Racematspaltungen bzw. -anreicherungen gelingen durch HPLC and Cellulose-tris(3,5-dimethylphenyl)carbamat und Poly(triphenylmethyl-methacrylat). Die Circulardichroismen der strukturisomeren Zehnringe und der protonierten Pyridinium-Verbindungen werden gemessen. Die Auswirkung der Chromophor-Orientierung auf den Circulardichroismus wird vergleichend erörtert.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19891220224
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  • 3
    Electronic Resource
    Electronic Resource
    Das erste helicale Naphthalinophan - Synthese, Enantiomerentrennung, Circulardichroismus und Racemisierungsbarriere (1989)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 122 (1989), S. 1113-1117 
    Details
    ISSN: 0009-2940
    Keywords: 1-Oxa-[2.2](2,7)naphthalenophane ; Helical molecules ; Ring strain ; Circular dichroism ; Thiaphanes ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: The First Helical Naphthalenophane - Synthesis, Separation off Enantiomers, Circular Dichroism, and Barrier of RacemisationPreparation and properties of the title compound (2; 1-Oxa-[2.2](2,7)naphthalenophane) are described. The enantiomers of 2 were separated or enriched by HPLC on cellulose-tris(3,5-dimethylphenyl)carbamate. Circular dichroism and kinetics of racemisation were elucidated. The energy barrier of ring inversion for the intermediate thia[3.2]phane 9 was determined. Spectroscopic and chiroptical properties are compared to the metacyclophane 1a and the [2.1]naphthalenophane 3.
    Notes: Erstmalige Darstellung und Eigenschaften der chiralen Titelverbindung (2; 1-Oxa[2.2](2,7)naphthalinophan) werden beschrieben. Deren Enantiomere wurden durch HPLC an Cellulose-tris-(3,5-dimethyphenyl)carbamat getrennt bzw. angereichert. Circulardichroismus und Racemisierungskinetik von 2 wurden ermittelt. Außerdem wurde die Energiebarriere für Ringinversion des intermediären Thia[3.2]phans 9 bestimmt. Spektroskopische und chiroptische Eigenschaften von 2 werden anhand des Metacyclophans 1a und des [2.1]Naphthalinophans 3 erörtert.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19891220617
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  • 4
    Electronic Resource
    Electronic Resource
    Intra- und extraannular funktionalisierte helical-chirale [2.2]Metacyclophane: Synthese, Circulardichroismus und Struktur-Chiroptik-Beziehungen (1990)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 123 (1990), S. 1859-1868 
    Details
    ISSN: 0009-2940
    Keywords: Circular dichroism ; [2.2]Metacyclophanes ; Helical molecules ; Absolute configuration ; Structure-chiroptic relationships ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Intra- und Extraannularly Functionalized Chiral [2.2]Metacyclophanes: Synthesis, Circular Dichroism, and Structure - Chiroptic RelationshipsA simple one-step cyclization reaction for the synthesis of the title compounds 1-5 is presented; separation (enrichment) of enantiomers is achieved by HPLC mainly on (+)-PTrMA. The kinetics of interconversion (racemization) of the new dihetera[2.2]metacyclophanes are determined: No racemization of the internally substituted phanes is found on heating until decomposition, whereas the extraannularly substituted compounds exhibit barriers of interconversion of about 130 kJ/mol, similar to that of the unfunctionalized skeleton 1a. For the pyridinophane 2 the barrier (110 kJ/mol) is lower corresponding to the decreased spatial requirement of the nitrogen lone pair compared to a C-H bond. The circular dichroism curves of the intraannularly functionalized phanes are compared with those of the extraannularly functionalized reference compounds: A bathochromic shift of the Cotton effect at short wavelengths is found, which is increasing with the bulkiness of the internal functional group.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19901230918
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  • 5
    Electronic Resource
    Electronic Resource
    Nitro- und Allyloxy-substituierte helicale [2.2]Metacyclophane: Synthese, Circulardichroismus und Röntgen-Kristallstrukturanalysen (1991)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 124 (1991), S. 1585-1590 
    Details
    ISSN: 0009-2940
    Keywords: Charge transfer ; Circular dichroism ; Helical molecules ; [2.2]Metacyclophanes ; Structure-chiroptic relationships ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Nitro- and Allyloxy-Substituted Helical [2.2]Metacyclophanes: Synthesis, Circular Dichroism and Crystal StructuresThe preparations of the title compound 3a, intraannularly nitro-functionalized, of the extraannularly substituted reference compound 3b, and of the sulfone 4 are described. Enantiomeric resolution of these helical phanes was accomplished on (+)-PTrMA and cellulose tris(3,5-dimethylphenyl)carbamate by HPLC. Racemization of the enantiomers of 3b is faster than that of the previously reported extraannularly substituted phanes. The crystal structure of 3a as well as that of the allyl ether 3d show severe distortions of the benzene rings; the CD spectrum of 3a is pointing at an intramolecular charge-transfer complex, an effect that cannot be evaluated from the CD spectrum of 3b.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19911240719
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  • 6
    Electronic Resource
    Electronic Resource
    Template synthesis of the first amide-based rotaxanes (1995)
    Weinheim : Wiley-Blackwell
    Liebigs Annalen 1995 (1995), S. 739-743 
    Details
    ISSN: 0947-3440
    Keywords: Interlocked rings ; Macrocycles ; Mechanical bond ; Rotaxanes ; Template effect ; Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The first rotaxanes 6a, 6b and 11 with an amide structure are described. Their (supramolecular template) syntheses are strikingly simple. The central part of the „axle“ is added to the „wheel“ and subsequently capped. The macromonocycle („wheel“) provides the receptor cavity for the „axle“ and the triphenylmethane stoppers confirm the mechanical bond between „wheel“ and „axle“.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jlac.1995199505109
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  • 7
    Electronic Resource
    Electronic Resource
    Non-Ionic Template Synthesis of Amide-Linked Rotaxanes: Olefinic and Aliphatic Axle Building Blocks (1997)
    Weinheim : Wiley-Blackwell
    Liebigs Annalen 1997 (1997), S. 2269-2273 
    Details
    ISSN: 0947-3440
    Keywords: Association constant ; Mechanical bonding ; Molecular recognition ; Template synthesis ; Supramolecular chemistry ; Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The first synthesis of amide-linked rotaxanes with non-arene axle building blocks is reported. The threading synthesis of rotaxane 8 with olefinic fumaryl chloride proves that arene moieties are not necessary for non-ionic template syntheses. Mass spectroscopic evidence of a rotaxane bearing an aliphatic axle, derived from succinic acid, revealed that hydrogen bonding, rather than π,π interactions, is the predominant template binding force. 1H-NMR titration studies on the threading synthesis of these mechanically bonded molecules were carried out. The association constants measured suggest that the incorporation of the corresponding monoamide monochloride (cf. 7), rather than the incorporation of the diacid dichloride (cf. 5), plays the key role in these rotaxane syntheses. The X-ray structural analysis of a semi axle (14) reveals hydrogen bonding patterns characteristic of diamides.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jlac.199719971114
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  • 8
    Electronic Resource
    Electronic Resource
    Chiral Amide Rotaxanes with Glucose Stoppers - Synthesis, Chiroptical Properties and Wheel-Axle Interactions (1998)
    Weinheim : Wiley-Blackwell
    Liebigs Annalen 1998 (1998), S. 2003-2007 
    Details
    ISSN: 1434-193X
    Keywords: Supramolecular chemistry ; Rotaxanes ; Mechanical bond ; Molecular recognition ; Chirality ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: In this paper we report on amide rotaxanes with tetrabenzoylglucose stoppers. When acetyl groups are used instead of benzoyl groups, merely a pseudo-rotaxane 5 is obtained. The circular dichroism measurements of the rotaxanes 6a and 6b differ significantly from that one of the free axle 7. Similarly, the Cotton effects of the mixtures of achiral wheels 2a and 2b and chiral axle indicate intermolecular host-guest interactions, likewise. After an addition of a solution of NaOMe the wheel is slipping off immediately and quantitatively by hydrolysis, as the benzoylglucose stoppers decrease in size by hydrolysis.
    Type of Medium: Electronic Resource
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  • 9
    Electronic Resource
    Electronic Resource
    Amide-Based [3]Catenanes and [2]Catenanes with Aliphatic Chains (2000)
    Weinheim : Wiley-Blackwell
    Liebigs Annalen 2000 (2000), S. 499-505 
    Details
    ISSN: 1434-193X
    Keywords: Catenanes ; Molecular recognition ; Template effect ; Mechanical bond ; Key-lock interaction ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: ---[3]Catenanes of the amide type were synthesized preparatively for the first time. Large macrocycles bearing two guest-binding sites were used to synthesize these amide-linked [3]catenanes in yields of 4%, either by formation of rigid macrocyclic boxes, or with macrocycles consisting of flexible long-chained aliphatic diamines. Furthermore, the systematic introduction of 1,ω-alkane diamines as building blocks for catenanes is described. The synthesis of a series of [2]catenanes by varying the ring size of one of the two macrocycles was also achieved in yields of 10%.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
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  • 10
    Electronic Resource
    Electronic Resource
    Azobenzene-Based Photoswitchable Catenanes (1995)
    Weinheim : Wiley-Blackwell
    Liebigs Annalen 1995 (1995), S. 649-656 
    Details
    ISSN: 0947-3440
    Keywords: Catenanes ; Interlocked rings ; Mechanical bond ; Photoswitches ; Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Four catenanes (1-4) and the corresponding tetracationic monocycles 5-8 are synthesized. X-ray structural analyses allow a prediction of the mobility (circumrotation) of the „interlocked“ rings in the catenanes, which is proven by 1H-NMR spectroscopy. An unexpected order in the crystal packing of 6 is demonstrated. (E/Z) isomerization in one ring influences the second ring of 1-4 and inversely. An existing obstacle inside the cavity of the switchable macrocycle can block this isomerization completely.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jlac.199519950491
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