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  • 1
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Chemistry - A European Journal 2 (1996), S. 624-633 
    ISSN: 0947-6539
    Keywords: catenanes ; macrocycles ; rotaxanes ; self-assembly ; tetrathiafulvalenes ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A general stepwise approach is described for the preparation of tetrathiafulvalene (TTF)-based linear and monoand dimacrocyclic compounds incorporating one or two 1,4-dioxyphenylene, 9,10-dioxyanthrylene, or 1,5- or 2,6-dioxynaphthylene units from readily available starting materials. By utilizing the π-π stacking interactions of the TTF unit with the dipyridinium dication of 1,1′-[1,4-phenylenebis (methylene)] bis-4,4′-bipyridinium bis(hexafluorophosphate), a rotaxane and two [2]catenanes were synthesized starting from the linear and monomacrocyclic compounds, respectively. From the dioxyphenylene-based dimacrocycle, three [3]pseudocatenanes (trans, cis, and a mixture of cis/trans isomers) were obtained with the trans compound as the major product. From the dioxyanthrylene dimacrocycle, only the trans-[3]pseudocatenane was obtained. Catenane products were formed quantitatively from the 1,5-dioxynaphthylene dimacrocycle in a template-directed reaction, affording a trans-[3]pseudo-catenane together with a [4]pseudocatenane (mixture of cis/trans isomers). From the 2,6-dioxynaphthylene dimacrocycle, a cis-[3]pseudocatenane was obtained as the major product and a trans-[3]pseudocatenane as the minor one. For the [3]pseudocatenanes (i.e., both the cis and trans catenanes), in which the TTF units were clamped by the tetracationic macrocycle, isomerizations were completely prevented even in the presence of trifluoroacetic acid. All new rotaxanes and catenanes were characterized by electrospray mass spectrometry, and the cis- and trans- [3]pseudocatenanes were additionally investigated by 1H NMR spectroscopy. The electrochemical and spectral properties of the rotaxane and the catenanes are reported. Catenane formation increases the redox potentials of the TTF unit. The results demonstrate the versatility of TTF as a building block in the construction of supramolecular structures.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
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  • 2
    ISSN: 1434-193X
    Keywords: Cyclophanes ; Electrochemistry ; Tetrathiafulvalenes ; Macrocycles ; Crystal structure ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A series of new macrobicyclic tetrathiafulvalenophanes of type 1 and 2 with three tetrathiafulvalene bridges has been prepared under high-dilution conditions using a stepwise selective protection-deprotection of tetrathiafulvalenethiolates. All the macrobicyclic tetrathiafulvalenes, along with the intermediate compounds 5 and 6 and the unexpected tetrathiafulvalene pentamers 17, were studied by cyclic voltammetry. An electrochemical investigation using the Bard-Anson equation and thin-layer cyclic voltammetry has been carried out, allowing an estimate of the number of electrons involved in each redox process of these multi-redox compounds. The X-ray crystal structure showing the unusual crystal packing of 2a is also presented.
    Type of Medium: Electronic Resource
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  • 3
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Liebigs Annalen 1999 (1999), S. 3335-3341 
    ISSN: 1434-193X
    Keywords: Catenanes ; Donor-acceptor interactions ; Self-assembly ; Supramolecular chemistry ; Tetrathiafulvalenes ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The synthesis of three novel macrocycles 3-5based on the two electron donors bis(2,5-dimethylpyrrolo)[3,4-d]tetrathiafulvalene (1) and 1,4-hydroquinone is presented. Their abilities to include the electron acceptor paraquat (6) have been investigated by UV/Vis and 1H NMR spectroscopy and an X-ray crystallographic analysis. Also, the complex formation between the cyclic acceptor cyclobis(paraquat-p-phenylene) (7) and different tetrathiafulvalene derivatives has been studied. A strong association between 1 and 7 facilitates the self-assembly of catenanes from the macrocycles 3-5. However, the preferred position of the cyclic acceptor 7in the catenanes around either the pyrrolo-annelated TTF or around the hydroquinone donor relies on a fine balance between all the individual noncovalent forces acting in cooperation.
    Additional Material: 5 Ill.
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  • 4
    ISSN: 0570-0833
    Keywords: catenanes ; crown ethers ; self-assembly ; tetrathiafulvalenes ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
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