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  • Articles: DFG German National Licenses  (20)
  • 1985-1989  (9)
  • 1960-1964  (11)
  • 1920-1924
  • Dyes/Pigments
  • Heterocycles
  • 1
    Electronic Resource
    Electronic Resource
    The Search for Highly Colored Organic Compounds (1989)
    Weinheim : Wiley-Blackwell
    Angewandte Chemie International Edition in English 28 (1989), S. 677-694 
    Details
    ISSN: 0570-0833
    Keywords: Color ; Conjugation ; Dyes/Pigments ; Chromophores ; Theoretical chemistry ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Until now the study of organic compounds in which the π-electron system is excited by absorbed light has been mainly concentrated on the ultraviolet and visible regions of the electromagnetic spectrum. Various new applications, such as the use of conjugated organic compounds as dye lasers or as materitals for storing information with the help of diode lasers, led to the synthesis of new compounds which absorb light in the near in infrared (NIR). It is possible to use structure-color relationships to predict the properties of such new compounds when they belong to dyestuff classes which have already been studied in detail; in this case the approach involves decreasing the energy difference between the ground state and the first excited state. A less conventional starting point is provided by molecular structures in which from the outset there is only a very small energy difference between the lowest-energy electronic states; such diradicaloid molecules occupy a special position among the various types of organic compounds. It is possible by means of suitable structural modification to stabilize such molecules in a singlet from which absorbs light at very long wavelengths (i.e. at small wave numbers).
    Additional Material: 10 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/anie.198906773
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  • 2
    Electronic Resource
    Electronic Resource
    Perspectives in Photochromism: A Novel System Based on the 1,5-Electrocyclization of Heteroanalogous Pentadienyl AnionsDedicated to Professor Emanuel Vogel and Professor Klaus Hafner on the occasion of their 60th birthdays (1989)
    Weinheim : Wiley-Blackwell
    Angewandte Chemie International Edition in English 28 (1989), S. 413-431 
    Details
    ISSN: 0570-0833
    Keywords: Photochromism ; Electrocyclic reactions ; Cyclization ; Pentadienyl anions ; Heterocycles ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The molecular process whereby light induces color changes in certain substances, namely photochromism, is currently a topic of active research. Many reactions - mainly monomolecular - have been reexamined in greater detail from the standpoint of photochromism. Those found to be especially suitable for such studies include cis-trans isomerizations, pericyclic reactions, tautomerizations and dissociations. The most important in this group are undoubtedly the electrocyclization reactions. In this paper we present spiro[fluorene-9,1′-[1,8a]-dihydroindolizine] and its bis- and tris-aza analogues as examples of a promising new system with a wide range of variability. Not only the classical uses, but also those in new fields such as frequency doubling of laser radiation, holography or molecular microcircuit chips can now be considered.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/anie.198904131
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  • 3
    Electronic Resource
    Electronic Resource
    Über enantiomerenreines (R)-2-Methyl-3-oxo-perhydro-1,4-oxazin (1988)
    Springer
    Monatshefte für Chemie 119 (1988), S. 839-844 
    Details
    ISSN: 1434-4475
    Keywords: Alpha haloesters ; Enantioselective synthesis ; Heterocycles ; Morpholinones ; Racemization
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract The synthesis of enantiomerically pure (R)-2-methyl-3-oxo-perhydro-1,4-oxazine is described for the first time. Stereochemical proofs are given and the formation of byproducts is discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00809695
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  • 4
    Electronic Resource
    Electronic Resource
    Flexibility and Rigidity of Proteins and Protein-Pigment ComplexesThe preceding page shows Figure 8c of this article. (1988)
    Weinheim : Wiley-Blackwell
    Angewandte Chemie International Edition in English 27 (1988), S. 79-88 
    Details
    ISSN: 0570-0833
    Keywords: Proteins ; Protein-pigment complexes ; Dyes/Pigments ; Dynamics ; X-ray structure analysis ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Proteins may be rigid or flexible to various degrees as required for optimal function. Flexibility of large parts of a protein, which rearrange or move, is particularly interesting and will be discussed in this article. We differentiate between several categories, although the boundaries between them are diffuse: flexibility of peptide segments, order-disorder transitions of spatially contiguous regions, and domain motions. The domains may be flexibly linked to allow rather unrestricted motions or the motions may be constrained to certain modes. The various categories of large-scale flexibility will be illustrated with the following examples: (1) Small protein proteinase inhibitors are rather rigid molecules which provide binding surfaces complementary to their cognate proteases but show also limited segmental flexibility and adaptation. (2) Large plasma proteinase inhibitors exhibit large conformational changes after interaction with proteases probably for regulatory purposes. (3) Pancreatic serine proteases employ a disorder-order transition of their activation domain as a means to regulate enzymic activity. (4) Immunoglobulins show rather unrestricted and also hinged domain motions in different parts of the molecule probably to allow binding to antigens in different arrangements. (5) Citrate synthase adopts open and closed forms by a hinged domain motion to bind substrates and release products and to perform the catalytic condensation reaction, respectively. (6) Riboflavin synthase, a bifunctional multienzyme complex, catalyzes two consecutive reactions by means of two subunits, α and β. The β-subunits form a shell, in which the α-subunits are enclosed. Diffusional motion of the catalytic intermediates is therefore restricted. In addition, rearrangement of the N-terminal segment occurs during the assembly of the β-subunit. In contrast, rigidity is dominant in the structures of the light-harvesting complexes and the photosynthetic reaction centers involved in photosynthetic light reactions. These are large protein-pigment complexes in which the proteins serve as matrices to hold the pigments in the appropriate conformation and relative arrangement. Since motion would contribute to deactivation of the photoexcited states of the pigments and diminish the efficiency of light-energy and electron transfer, the functional role of rigidity is easy to rationalize for these proteins.
    Additional Material: 10 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/anie.198800791
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  • 5
    Electronic Resource
    Electronic Resource
    Ketenimine Complexes from Carbene Complexes and Isocyanides: Versatile Building Blocks for Carbocycles and N-Heterocycles [New Synthetic Methods (74)]Dedicated to Professor Ernst Otto Fischer on the occasion of his 70th birthday (1988)
    Weinheim : Wiley-Blackwell
    Angewandte Chemie International Edition in English 27 (1988), S. 1456-1467 
    Details
    ISSN: 0570-0833
    Keywords: Ketenimines ; Carbene ligands ; Isocyanides ; Carbocycles ; Heterocycles ; Synthetic methods ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Ketenimine complexes are readily available in great variety by reaction of isocyanides with carbene complexes. They have proven to be useful building blocks in new synthetic approaches to carbocyclic and N-heterocyclic four-, five-, and six-membered rings. The reactions involve new metal-induced bond formation patterns of the ketenimine ligands, which can be influenced across a wide range by varying the following five parameters: the metal, the ligands, and the three substituents on the N=C=C unit.
    Additional Material: 8 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/anie.198814561
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  • 6
    Electronic Resource
    Electronic Resource
    Phosphaalkynes - Syntheses, Reactions, Coordination Behavior [New Synthetic Methods (73)]Phosphorus Compounds with Unusual Coordination, Part 30. Part 29: [119]. (1988)
    Weinheim : Wiley-Blackwell
    Angewandte Chemie International Edition in English 27 (1988), S. 1484-1508 
    Details
    ISSN: 0570-0833
    Keywords: Phosphaalkynes ; Synthetic methods ; Phosphorus-carbon compounds ; Multiple bonds ; Heterocycles ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Organophosphorus compounds have been applied in two ways in chemical synthesis. They can either be used as a reagent in a step of the synthesis (for example, in the Wittig reaction) or they can be incorporated directly into the target molecule. This second application, in particular, has expanded greatly in the last few years with the preparation of low-coordination phosphorus compounds. These include the phosphaalkynes, which are of great interest to organic and inorganic chemists. Phosphaalkynes have been employed in the synthesis of heterocyclic compounds, phosphaarenes and their valence isomers, and polycyclic compounds. Further applications have been the use of phosphaalkynes as new ligand systems in complex chemistry and their cyclooligomerization with organometallic reagents. While the chemical properties of phosphaalkynes have little in common with those of nitriles, they are in many ways very similar to those of the isoelectronic acetylenes.
    Additional Material: 4 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/anie.198814841
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  • 7
    Electronic Resource
    Electronic Resource
    A new convenient synthetic method for 3,4-diaryl-2,6-piperidinediones (1987)
    Springer
    Monatshefte für Chemie 118 (1987), S. 987-991 
    Details
    ISSN: 1434-4475
    Keywords: Heterocycles ; Piperidinediones
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Durch saure Hydrolyse der entsprechenden Ethyl-3,4-diaryl-4-cyanobutyrate wurden in einem Schritt (Eintopfreaktion) die 3,4-Diaryl-2,6-piperidindione dargestellt.
    Notes: Abstract A one-pot reaction for the preparation of 3,4-diaryl-2,6-piperidinediones through acid hydrolysis of the corresponding ethyl 3,4-diaryl-4-cyanobutyrates is described.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00815326
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  • 8
    Electronic Resource
    Electronic Resource
    Study of the effect of N-protonation and N-methylation on the 1H and 13C chemical shifts of the six-membered ring in benzazoles and 2-substituted N,N-dimethylamino derivatives (1986)
    Chichester : Wiley-Blackwell
    Organic Magnetic Resonance 24 (1986), S. 415-420 
    Details
    ISSN: 0749-1581
    Keywords: Heterocycles ; Benzazoles ; Amino Derivatives ; Cation formation ; 1H and 13C ; NMR ; Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The 1H and 13C NMR spectral data of benzimidazole, benzoxazole, benzothiazole and N-methylbenzimida-zole and of their 2-N,N-dimethylamino derivatives are reported. The spectra were recorded in acetone-water solution. The chemical shifts of these molecules are compared with those of the corresponding cations obtained by N-protonation and N-methylation of the neutral molecules. The carbon atoms C-4, C-5, C-6 and C-4a show a qualitatively identical behaviour, moving to higher field when the cations are formed from the benzazoles examined, but a different behaviour is found for C-2, C-7 and C-7a, which depends on the heterocyclic ring, on the presence of the substituent in position 2 and on the type of cation formed (N-protonation and N-methylation cause different effects). The conversion of benzazoles into the corresponding cations causes all 1H chemical shifts to move to lower field.
    Additional Material: 8 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/mrc.1260240505
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  • 9
    Electronic Resource
    Electronic Resource
    [3+2] Cycloaddition Approaches to Five-Membered Rings via Trimethylenemethane and Its Equivalents [New Synthetic Methods (55)] (1986)
    Weinheim : Wiley-Blackwell
    Angewandte Chemie International Edition in English 25 (1986), S. 1-20 
    Details
    ISSN: 0570-0833
    Keywords: Cycloaddition ; Trimethylenemethane ; Synthetic methods ; Cyclopentanes ; Heterocycles ; Natural products ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The power of cycloadditions for ring formation derives from the potential for chemo-, regio-, diastereo-, and enantioselectivity. Trimethylenemethane (TMM) and its equivalents offer the possibility of extending such benefits to the synthesis of five-membered rings. Three types of conjunctive reagents appear to be promising candidates: (1) selected 4-alky-lidene-4,5-dihydro-3H-pyrazoles, (2) 2-[(trimethylsilyl)methyl]allyl esters and halides, and (3) alkylidenecyclopropanes. Thermal reactions, especially intramolecular ones, effect the cycloaddition of the pyrazoles to olefins-especially electron-poor olefins. The latter two precursors require a catalyst, notably a palladium complex, to unlock the synthetic potential. With the 2-[(trimethylsilyl)methyl]allyl esters, a general chemo-, regio-, and diastereoselective cycloaddition with typical Diels-Alder dienophiles forms methylenecyclopentanes in both inter- and intramolecular fashion. A tin analogue allows extension of this cycloaddition to aldehydes, and, in a related sequence, to ketones and imines to form 3-methylenete-trahydrofurans and 3-methylenepyrrolidines with excellent diastereoselectivity. The 2-[(tri-methylsilyl)methyl]allyl esters also serve to effect net methylenecyclopentane annulation to cyclic enols. Such adducts can further undergo three-carbon intercalation or combined ring contraction-spiroannulation simply by the use of either a nucleophilic or electrophilic trigger. Alkylidenecyclopropanes undergo cycloadditions to both electron-rich and electron-poor olefins when stimulated by metal catalysts, especially palladium. A complementary regiochemistry to the approach based upon silicon conjunctive reagents is observed. The availability of these cycloadditions provides new strategies for the synthesis of natural products.
    Additional Material: 2 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/anie.198600013
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  • 10
    Electronic Resource
    Electronic Resource
    New Reactive DyesDedicated to Professor H. Bredereck on the occasion of his 60th birthday (1964)
    Weinheim : Wiley-Blackwell
    Angewandte Chemie International Edition in English 3 (1964), S. 408-416 
    Details
    ISSN: 0570-0833
    Keywords: Reactive dyes ; Dyes/Pigments ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Two new groups of reactive dyestuffs have been developed. One group (Levafix® dyes) comprises compounds which contain —SO2NH—CH2—CH2—OSO3H or —CH2—N(alkyl)-CH2—CH2—OSO3H as reactive groups. The dyes of this group react with cellulose fibers to form cellulose ethers, e.g. R—SO2NH—CH2—CH2—O—cellulose. The substances in the second group (Levafix-E® dyes) consist of the amides formed from 2,3-dichloroquinoxaline-6-carboxylic acid and dyestuffs containing primary or secondary amino groups.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/anie.196404081
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  • 11
    Electronic Resource
    Electronic Resource
    Three-Membered Rings Containing Two Hetero-Atoms (1964)
    Weinheim : Wiley-Blackwell
    Angewandte Chemie International Edition in English 3 (1964), S. 333-341 
    Details
    ISSN: 0570-0833
    Keywords: Strained molecules ; Heterocycles ; Diaziridines ; Diazirines ; Oxaziranes ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Since their discovery five years ago, the diaziridines have become an extensive and easily accessible class of compounds. Hydrolysis of these compounds effects a simple synthesis of hydrazine, alkylhydrazines, and N,N′-dialkylhydrazines. They are also powerful oxidizing agents. The rigidity of the three-membered ring gives rise to a few stereoelectronic peculiarities. Investigations on the mechanism of formation of the three-membered rings led to a new synthesis of oxaziranes and to discovery of the isomeric oximes with a three-membered ring structure. The latter decompose readily to form diimide. Diazirines are cyclic isomers of the aliphatic diazo compounds and are surprisingly easy to obtain by dehydrogenation of suitable diaziridines; they are chemically much more stable than the linear isomers. Grignard reagents add onto the N=N double bond without destruction of the three-membered ring. Thermal decomposition yields carbenes.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/anie.196403331
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  • 12
    Electronic Resource
    Electronic Resource
    Kinetics and Mechanism of 1,3-Dipolr CycloadditionsExtended version of a lecture given at the Annual Meeting of the Dechema in Frankfurt/Main on June 14th, 1962, and of the Max Tishler Lecture at Harvard University on December 10th, 1962. (1963)
    Weinheim : Wiley-Blackwell
    Angewandte Chemie International Edition in English 2 (1963), S. 633-645 
    Details
    ISSN: 0570-0833
    Keywords: Kinetics ; Dipolar cycloaddition ; Cycloaddition ; Heterocycles ; Reaction mechanisms ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Criteria for the mechanism of 1,3-dipolar cycloadditions which lead to 5-membered rings are provided by the stereoselectivity observed with cis-trans isomeric dipolarophiles, by the effect of solvent and substituents on the rate constants, by the activation parameters, and by orientation phenomena. A concerted addition, which can also be described in terms of molecular orbitals and in which the two new σ-bonds are formed simultaneously, although not necessarily at equal rates, offers the best explanation of the experimental facts.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/anie.196306331
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  • 13
    Electronic Resource
    Electronic Resource
    Reactive Dyes Containing Vinylsulfonyl GroupsPublished on the occasion of the 100th anniversary of the founding of Farbwerke Hoechst AG. on January 11th, 1963 (1963)
    Weinheim : Wiley-Blackwell
    Angewandte Chemie International Edition in English 2 (1963), S. 20-23 
    Details
    ISSN: 0570-0833
    Keywords: Reactive dyes ; Dyes/Pigments ; Reactive dyes ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Compounds and dyes containing vinylsulfonyl groups or groupings which readily yield vinylsulfonyl groups possess a marked ability to add onto many compounds containing active hydrogen under alkaline conditions. They also react with natural substances of high molecular weight, e.g. wool and cellulose, which contain amino- or hydroxyl groups. These reactions lead to the formation of strong covalent bonds between the reactants. As a result of this finding, reactive dyes for nitrogenous and cellulose fibers have been developed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/anie.196300201
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  • 14
    Electronic Resource
    Electronic Resource
    Polycondensation Dyes. A New Principle for the Preparation of Wash-Fast Cotton DyeingsPublished on the occasion of the 100th anniversary of the foundation of Farbwerke Hoechst on January 11th, 1963 (1963)
    Weinheim : Wiley-Blackwell
    Angewandte Chemie International Edition in English 2 (1963), S. 30-31 
    Details
    ISSN: 0570-0833
    Keywords: Polycondensation ; Dyes/Pigments ; Bunte salts ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Dyes which contain only thiosulfate residues as water-solubilizing groups are readily polycondensed on cellulose under mild conditions in the presence of condensing agents such as sodium sulfide to give insoluble, high molecular-weight dyes. This type of fixation leads to wash-fast dyeings and, in contrast to reactive dyes, involves no reaction with the fiber. The preparation and application of the dyes are described.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/anie.196300301
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  • 15
    Electronic Resource
    Electronic Resource
    Syntheses of Heterocyclic Compounds from Aminoguanidine (1963)
    Weinheim : Wiley-Blackwell
    Angewandte Chemie International Edition in English 2 (1963), S. 459-476 
    Details
    ISSN: 0570-0833
    Keywords: Aminoguanidine ; Heterocycles ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Due to its unique structure, aminoguanidine is capable of reacting as a derivative of hydrazine, guanidine or formamidine. Addition and condensation reactions yield products which can be cyclized to heterocyclic compounds. Frequently, heterocyclics are directly accessible from aminoguanidine in one stage.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/anie.196304591
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  • 16
    Electronic Resource
    Electronic Resource
    1,3-Dipolar Cycloadditions. Past and FutureExtended version of lectures given at the Chemists' Meeting in Vienna (Austria) October 1961, and at the Gordon Research Conference, New Hampton (U.S.A.), 1961. (1963)
    Weinheim : Wiley-Blackwell
    Angewandte Chemie International Edition in English 2 (1963), S. 565-598 
    Details
    ISSN: 0570-0833
    Keywords: Dipolar cycloaddition ; Cycloaddition ; Heterocycles ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: In contrast to the very large number of special methods applicable to syntheses in the heterocyclic series, relatively few general methods are available. The 1,3-dipolar addition offers a remarkably wide range of utility in the synthesis of five-membered heterocycles. Here the “1,3-dipole”, which can only be represented by zwitterionic octet resonance structures, combines in a cycloaddition with a multiple bond system - the “dipolarophile” - to form an uncharged five-membered ring. Although numerous individual examples of this reaction were known, some even back in the nineteenth century, fruitful development of this synthetic principle has been achieved only in recent years.
    Additional Material: 4 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/anie.196305651
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  • 17
    Electronic Resource
    Electronic Resource
    Mixed-Phase Pigments with Rutile Structures (1962)
    Weinheim : Wiley-Blackwell
    Angewandte Chemie International Edition in English 1 (1962), S. 41-45 
    Details
    ISSN: 0570-0833
    Keywords: Dyes/Pigments ; Rutile structure ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Until the present time, new color pigments have been developed by isotypic and homotypic mixed-phase formation. This paper deals primarily with heterotypic mixed-phase formation for the preparation of new colored and white pigments with the rutile structure. Dioxides and difluorides crystallizing in the rutile lattice-form were chosen as host-lattices for the mixed-phase formation. Hosts of the general formula AB2 can accommodate, as guests, in the form of solid solutions, oxides and/or fluorides with different structures. Characteristically, the mean statistical cation-radius lies between 0.55 and 0.98 Å, with single radii between 0.46 and 0.98 Å. Relative quantities are so chosen that the cation to anion ratio of 1:2 prescribed by the host lattice, as well as electroneutrality, is maintained.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/anie.196200411
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  • 18
    Electronic Resource
    Electronic Resource
    Heterocyclic Azo Dyes by Oxidative CouplingXXIII. Communication in this series. XII. Communication, S. Hünig and F. Müller, Liebigs Ann. Chem. 651, 89 (1962).Dedicated to Prof. Dr. O. Bayer on the occasion of his 60th birthday. (1962)
    Weinheim : Wiley-Blackwell
    Angewandte Chemie International Edition in English 1 (1962), S. 640-646 
    Details
    ISSN: 0570-0833
    Keywords: Azo dyes ; Dyes/Pigments ; Oxidative coupling ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: New findings in the field of oxidative coupling reactions are reported. These involve: extension of this type of reaction to amidrazone system displaying (vinylogous) tautomerism and to unsymmetrical diarylhydrazines; elucidation of the coupling mechanism for these arylhydrazines and for the amidrazone systems previously described; the properties of some dyes, complexed with heavy metals, and the synthesis of tetraazapentamethine and penta-azapentamethine dyes.
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/anie.196206401
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  • 19
    Electronic Resource
    Electronic Resource
    Dyeing of Poly(acrylonitrile) Fibers with Azatrimethinecyanines (1962)
    Weinheim : Wiley-Blackwell
    Angewandte Chemie International Edition in English 1 (1962), S. 532-537 
    Details
    ISSN: 0570-0833
    Keywords: Polyacrylonitrile ; Fibers ; Azatrimethinecyanines ; Dyes/Pigments ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Like all basic dyes, azatrimethinecyanines possess a good dyeing affinity for acrylic fibers. Compounds with isolated nitrogen atoms in the trimethine chain show insufficient light fastness, whereas good to excellent fastness to light is displayed by compounds having neighboring nitrogen atoms in the chain. Thus, a working hypothesis stating that the light fastness of trimethinecyanines on acrylic fibers is improved by progressive replacement of methine groups by nitrogen atoms has been partially confirmed.
    Additional Material: 3 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/anie.196205321
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  • 20
    Electronic Resource
    Electronic Resource
    Reactivity of Dichloro- and Trichloropyrimidyl Dyes and the Sensitivity of their Dyeings to Hydrolysis (1962)
    Weinheim : Wiley-Blackwell
    Angewandte Chemie International Edition in English 1 (1962), S. 568-572 
    Details
    ISSN: 0570-0833
    Keywords: Trichloropyrimidyl dyes ; Dyes/Pigments ; Dichloropyrimidyl dyes ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Several examples are used to show that the reactivity of dichloro- and trichloropyrimidyl dyes and the sensitivity of their dyeings to hydrolysis are determined by the nature of the bridge unit between the chromophore and the reactive system. The tendency of the dyeings to hydrolyze in acid and, more particularly, in alkaline media increases with increasing reactivity of the dyes. In alkaline media, dyeings made with dyes containing oxygen bridges are cleaved mainly between the reactive system and the chromophore, while in dyeings made with dyes containing imino or methylimino bridges, the linkage between the reactive system and the cellulose is hydrolyzed.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/anie.196205681
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