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  • Macrocycles  (9)
  • [2.2]Metacyclophanes  (3)
  • Decarbonylation  (2)
  • 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. 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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  • 3
    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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  • 4
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 126 (1993), S. 97-101 
    ISSN: 0009-2940
    Keywords: Cyclophanes ; Decarbonylation ; Paracyclophanes ; Pyrolysis ; Ketone pyrolysis, selective ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Selective Ketone Pyrolysis: New ExamplesThe known ketone 4, the new paracyclophane ketones 6, 7, and 9-12 and the known hydrocarbons 5, 8, and 13 are obtained by successive thermal extrusion of carbon monoxide from the [3n]paracyclophane(ones)n 1, 2, and 3 (n = 2,3,4). The X-ray structure analyses of the 20-membered 6 and the 26-membered ring 10 are reported.
    Additional Material: 2 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. 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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  • 6
    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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  • 7
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 127 (1994), S. 2089-2096 
    ISSN: 0009-2940
    Keywords: Aza-phanes ; Cyclophanes ; Molecular belts ; Macrocycles ; CH-π interaction ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A New Deltaphane and Ribbon-Shaped CyclophanesThe reaction of the fourfold functionalized [3.3][3.3]metacyclophane 8 with tosylamide monosodium salt leads to a new deltaphane in quantitative yield. An X-ray analysis confirms the belt-shaped structure of 3. Moreover, a series 10-15 of well-soluble belt-shaped macrocycles with up to 21 interconnected benzene rings were detected. The intermediate [3.3][3.3]metacyclophane 4 shows remarkably short distances to enclosed toluene, one toluene molecule acting twice as a π acceptor and once as a π donor. Competition experiments with benzene demonstrate the dependence of conformational behaviour on the solvent.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
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  • 8
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 124 (1991), S. 897-902 
    ISSN: 0009-2940
    Keywords: Biphenylophane ; Kharasch coupling reaction ; Macrocycles ; TCNQ ; TTF ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Molecules of the TTF and TCNQ Type with Macrocyclic SkeletonsThe electron-rich and electron-poor macrocycles 1 - 3 have been synthesized. Their [1.1](3,3′)biphenylophane framework is formed by Kharasch reaction. Whereas in the well-known donors and acceptors I-III the functionalities are conjugated, in their macrocyclic “analogues” 1-3 the conjugation is prevented by the meta-connection of the phenylene rings. The redox properties  - studied by cyclovoltammetry  -  are discussed. The X-ray analysis of 3 shows considerable deviations from a planar structure.
    Additional Material: 5 Ill.
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  • 9
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 124 (1991), S. 1415-1423 
    ISSN: 0009-2940
    Keywords: [2.2]Metacyclophanes ; Chromium tricarbonyl complexes ; Chirality, helical, planar ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Regioselective Substitution of [2.2]Metacyclophanes via Chromium Tricarbonyl ComplexesThe [2.2]metacyclophanes 6, 8, and 9 are regioselectively complexed with triammintricarbonylchromium. The complexes are lithiated with nBuLi/TMEDA at -78°C, and the resulting aryllithium complexes are trapped with electrophiles to give new phanes exhibiting substitution patterns, which are not or more difficult available by other routes. Complex 6a gives 5-substitution almost exclusively, while the chiral complex 8a is substituted in positions 5 and 4 in a ratio of 3:1. Steric effects, caused by the large dithiane group, seem to play a role in both complexation and derivatisation of these substrates. An X-ray crystal structure analysis of the chromium tricarbonyl phane complex 11 is performed.
    Additional Material: 3 Ill.
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  • 10
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 127 (1994), S. 767-777 
    ISSN: 0009-2940
    Keywords: Azaphanes ; Cyclophanes ; Macrocycles ; Molecular belts ; Multistep strategy ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Belt-Shaped Molecules by a Repetitive Synthetic StrategyBelt-shaped molecules of the general type 2 containing up to five benzene ring units (cf. 37) have been synthesized by macrocyclisation reactions of ribbon-shaped precursors. An intermolecular cyclization step generates the macroheterocycles 38 and 40. The fourfold-bridged cyclophane 36 are prepared by intra-and intermolecular cyclization reactions. The X-ray structure analyses of 14, 16, 22, 23, 28, and 36 show S-shaped conformations of the molecules.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
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