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  • 1
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 130 (1997), S. 801-806 
    ISSN: 0009-2940
    Keywords: Unsymmetrical phthalocyanines ; Hemiporphyrazines ; Macrocyclic bisdienes and bisdienophiles ; Diels-Alder reactions ; Ladder polymers ; Cycloaddition ; Macrocycles ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The specific synthesis of a metal-free bisdienophilic phthalocyanine 193, suitable for repetitive Diels-Alder reactions, is reported. This was achieved by condensation of 191,3,3-trichloro-6/7-nitroioindolenine (191) and 4,9-dibutoxy-2,3,5,8-tetrahydro-1,3-diimino-1H-5,8-epoxybenz[f]isoindoline (2). The ability of 3 to undergo Diels-Alder reactions was tested by reaction with an excess of 1,2,3,4-tetraphenylcyclopentadienone (5). Experimental data of the hemiporphyrazines 9, 10, and 11, which can be used as precursors for the synthesis of ladder polymers, are also given in the Experimental Section.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
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  • 2
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 130 (1997), S. 1375-1378 
    ISSN: 0009-2940
    Keywords: Phthalocyanines ; Hemiporphyrazines ; Fullerenes ; Diels-Alder reactions ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The synthesis of a new Diels-Alder adduct 7 of [60]fullerene and a phthalocyaninenickel compound containing a longer spacer than the originally reported Diels-Alder adduct 1 is described. The bisenophilic hemiporphyrazinenickel compound 11 reacts with [60]fullerene to form a Diels-Alder adduct 12 containing two fullerene units. Spectroelectrochemical investigations of 7 and 12 reveal multiple reductions, which are attributed to the corresponding subunits of the molecules. In contrast to 1, the election acceptor properties of the [60]fullerene unit in both molecules have no influence on the electronic properties of the phthalocyanine and hemiporphyrazine, respectively.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
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  • 3
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 1999 (1999), S. 693-703 
    ISSN: 1434-1948
    Keywords: (Phthalocyanine)nickel complexes ; Unsymmetrical phthalocyanines ; Isobenzofurans ; Diels-Alder reactions ; Ladder-type molecules ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The octasubstituted (phthalocyanine)nickel complexes 4a,b, soluble in common organic solvents, bearing four dienophilic functionalities were synthesized from the corresponding phthalodinitriles 3a,b and nickel(II) acetate. Reaction of 4a with tetracyclone 5 led to the phthalocyanine-tetracyclone adduct 6 which is a precursor for an intermediate phthalocyanine 7 containing four isobenzofuran moieties. The capability of 7 to react as tetrakis(diene) was demonstrated by its reaction with naphthoquinone. Furthermore, the unsymmetrical phthalocyanines 13 and 16a,b,c containing one dienophilic functionality were synthesized using a statistical approach. Their tetracyclone adducts 17, 18a,b,c can be used for the synthesis of ladder-type phthalocyanine dimers. The dimer 22 was synthesized from 18c and p-benzoquinone via the isobenzofuran intermediate 19 and the benzoquinone adduct 21. For dehydration experiments the naphthoquinone monoadduct 23 was synthesized from 18c. Dehydration of 22 and 23 was carried out successfully with p-toluenesulfonic acid. The Diels-Alder reactions are discussed with respect to the occurring exo/endo ratio.
    Type of Medium: Electronic Resource
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  • 4
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Liebigs Annalen 1999 (1999), S. 1687-1691 
    ISSN: 1434-193X
    Keywords: Nickel phthalocyanines ; Phthalocyanines ; Diels-Alder reactions ; Polymers ; Wittig reactions ; Cycloadditions ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The nickel phthalocyanine 4, which is soluble in common organic solvents, has been synthesized from the corresponding tetracyclone monoadduct 1 and acrolein (3). Reaction of 4 with p-toluenesulfonic acid leads to the modified phthalocyanine monoaldehyde 5. The capability of 5 to undergo a Wittig reaction has been demonstrated with benzyltriphenylphosphonium bromide (6). Furthermore, a dimer 9 has been synthesized by treating 5 with 0.5 equiv. of xylylenebis(triphenylphosphonium bromide) (8). Dimer 9 constitutes a model compound for corresponding PPV polymers containing phthalocyanine subunits.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
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  • 5
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Liebigs Annalen 1989 (1989), S. 833-845 
    ISSN: 0170-2041
    Keywords: Pyrethroids ; Olefins, bis(trifluoromethyl)-substituted ; Caronaldehydic acid ethyl ester, hexafluoro- ; Fenvalerate, hexafluoro- ; Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Synthesis of Bis(trifluoromethyl)-Substituted PyrethroidsA method for the preparation of 1,1-bis(trifluoromethyl)-substituted pyrethroids is described. For this purpose, 1,1-bis(trifluoromethyl)-substituted olefins 9 are prepared by an easy method from the aldehydes 17 with 2,2-dichlorohexafluoropropane (16) and triphenylphosphine and converted into 2,2-bis(trifluoromethyl)cyclopropanecarboxylates 5a, g, h, i by reacting with (ethoxy-carbonylmethylene)dimethylsulfurane (10). Ethyl 3-formyl-2,2-bis(trifluoromethyl)cyclopropanecarboxylate (hexafluorocaronaldehydic acid ethyl ester) (5c) is obtained from 4,4,4-trifluoro-3-(trifluoromethyl)-2-butenal diethyl acetal (9c) and the sulfurane 10. Compound 5c is an important intermediate in the preparation of the bis(trifluoromethyl)-substituted pyrethroid esters 5d-f. The hydrolysis of the esters 5a, h affords the corresponding carboxylic acids 6a, b which are converted into the pyrethroid esters 7a, b via the acyl chlorides 38 by treating with α-cyano-3-phen-oxybenzyl alcohol (39). 1-(4-Chlorophenyl)-3,3,3-trifluoro-2-(trifluoromethyl)-1-propene (9g) reacts with acetone cyanohydrin to the nitrile 47. The acyl chloride 49 obtained from the nitrile 47 via the carboxylic acid 48 is treated with α-cyano-3-phenoxybenzyl alcohol (39) to form hexafluorofenvalerate (8).
    Notes: Es wird über eine Methode zur Darstellung von 1,1-bis(trifluor-methyl)substituierten Pyrethroiden berichtet. Dazu werden 1,1-bis(trifluormethyl)substituierte Olefine 9 auf einfache Weise durch Reaktion der Aldehyde 17 mit 2,2-Dichlorhexafluorpropan (16) und Triphenylphosphan dargestellt und mit (Ethoxycarbonylmethylen)dimethylsulfuran (10) in die 2,2-Bis(trifluormethyl)cyclo-propancarbonsäureester (5a, g, h, i) übergeführt. Ausgehend von 4,4,4-Trifluor-3-(trifluormethyl)-2-butenal-diethylacetal (9c) wird durch Umsetzung mit dem Sulfuran 10 der 3-Formyl-2,2-bis(trifluormethyl)cyclopropancarbonsäure-ethylester (Hexafluorcaronaldehydsäure-ethylester) (5c) erhalten. 5c stellt eine wichtige Zwischenstufe zur Darstellung der bis(trifluormethyl)substituierten Pyrethroidester 5d-f dar. Die Hydrolyse der Esterfunktion in den Pyrethroidestern 5a, h liefert die Carbonsäuren 6a, b, die über die Säurechloride 38 und Umsetzung mit α-Cyan-3-phenoxy-benzylalkohol (39) in die entsprechenden Pyrethroidester 7a, b übergeführt werden. 1-(4-Chlorphenyl)-3,3,3-trifluor-2-(trifluor-methyl)-1-propen (9g) reagiert mit Aceton-cyanhydrin zum Nitril 47. Nach Überführung in die Carbonsäure 48 und das Säurechlorid 49 wird dieses mit α-Cyan-3-phenoxybenzylalkohol (39) zum Hexafluorfenvalerat (8) umgesetzt.
    Type of Medium: Electronic Resource
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  • 6
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Liebigs Annalen 1991 (1991), S. 1013-1020 
    ISSN: 0170-2041
    Keywords: Pyrethroids ; Olefins, bis(trifluoromethyl)-substituted ; Caronaldehydic acid methyl ester, hexafluoro- ; Chrysanthemic acid, hexafluoro- ; Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Synthesis of cis-Configurated Bis(trifluoromethyl)pyrethroidstrans-2,2-Bis(trifluoromethyl)cyclopropanecarboxylates 2a, b are converted into the cis-diastereomers by base-catalyzed epimerization via the bicyclic lactones 3a, b. Dehydration of cis-2a and cleavage of the ester function leads to the fluorinated chrysanthemic acid 4b, which is converted into the pyrethroids 4d, e. cis-2b is oxidized by pyridinium chlorochromate to give methyl cis-3-formyl-2-2-bis(trifluoromethyl)-cyclopropanecarboxylate (hexafluorocaronaldehydic acid methyl ester) (5). This compound, which is very sensitive to isomerization, is converted into the pyrethroid esters 6a, b predominately retaining the cis configuration; however, by introducing the 2,2-dichlorovinyl side chain the trans diastereomer is obtained. The starting materials trans-2a, b are prepared by the reaction of aldehydes 9a, b with 2,2-dichlorohexafluoropropane and triphenylphosphine followed by cyclopropanization of the resulting 1,1-bis(trifluoromethyl)olefins 10a, b with (ethoxycarbonylmethylene)dimethylsulfurane (14).
    Type of Medium: Electronic Resource
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