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  • 1
    Electronic Resource
    Electronic Resource
    Influence of structure of alkenes on their retention on different stationary phases (1988)
    Springer
    Chromatographia 25 (1988), S. 655-658 
    Details
    ISSN: 1612-1112
    Keywords: Gas chromatography ; Structure-retention relationships ; Connectivity indices, topological indices ; Alkenes
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Summary Retention indices of different alkenes are correlated with connectivity and topological parameters. The appropriate statistically valid relations hips are derived and discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02327667
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  • 2
    Electronic Resource
    Electronic Resource
    On-line gas chromatographic analysis of light Fischer-Tropsch synthesis products (1986)
    Springer
    Chromatographia 21 (1986), S. 265-268 
    Details
    ISSN: 1612-1112
    Keywords: Capillary gas chromatography ; Alumina PLOT columns ; C1−C7 hydrocarbons ; Alkenes ; Fischer-Tropsch products
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Summary A simple gas chromatographic system has been developed for the rapid on-line analysis of light Fischer-Tropsch products. This involves a single chromatography fitted with two columns, a porous-layer open-tubular column coated with KCl deactivated alumina and a packed Porapak-Q column. The capillary column separates the 16 most common C1−C4 hydrocarbons and permits a reasonable analysis of the hydrocarbons in the C5−C7 range. The packed column is used for the separation of methane, carbon monoxide, carbon dioxide, water and methanol. Retention characteristics for the analysis on the capillary column are presented. The total analysis cycle is 30 minutes.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02311879
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  • 3
    Electronic Resource
    Electronic Resource
    Oxidation of propene and 1-butene byMethylococcus capsulatus andMethylosinus trichosporium (1986)
    Springer
    Journal of industrial microbiology and biotechnology 1 (1986), S. 119-127 
    Details
    ISSN: 1476-5535
    Keywords: Olefins ; Alkenes ; Epoxidation ; Biotransformation ; Methylococcus capsulatus ; Methylosinus trichosporium
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Summary Methane-grown cells ofMethylococcus capsulatus andMethylosinus trichosporium readily oxidized propene and various isomers of butene to their respective epoxides. When examined in a proton NMR spectrum using tris([3-trifluoromethylhydroxymethylene]-d-camphorato), europium III derivative as an optically active chemical shift reagent, the products propylene oxide and 1,2-epoxybutane were found to contain equal amounts of both isomers. Methane-grown cells of both bacteria had considerable levels of reducing equivalents to catalyze the epoxidation of gaseous olefins. Cells depleted of reductants catalyzed the oxidation in the presence of low levels of methanol or formaldehyde with a stoichiometry of about 2:1. The rates of epoxidation of propene and 1-butene in a continuous reactor were 2–3-times that of a batch-wise reaction; the epoxidation activity, however, was lost within 3 h. The inactivation was attributed to the reactivity of the accumulated epoxides in the reactor. Propene and 1-butene oxidation by both bacteria were drastically inhibited by the respective products. Thus, the major problem in the application of microorganisms for production of epoxides from gaseous olefins is the rapid separation of the reactive products.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01569320
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  • 4
    Electronic Resource
    Electronic Resource
    Gas chromatographic retention indices for alkenes on OV-101 and squalane capillary columns (1986)
    Springer
    Chromatographia 21 (1986), S. 149-151 
    Details
    ISSN: 1612-1112
    Keywords: Gas chromatography ; Retention indices ; Comparison of data ; Alkenes
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Summary Gas chromatographic retention indices for 47 C5 to C8 alkenes on OV-101 dimethylsilicone at 50 and 70 °C were determined within a standard deviation of 0.3i.u. Data obtained on OV-101 are compared with those measured on squalane. The comparison of the retention index and dl/dT values from both columns is presented as linear regression equations with correlation coefficients greater than 0.98.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02311743
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  • 5
    Electronic Resource
    Electronic Resource
    13C NMR and lanthanide-induced shifts in epoxides of Terpenes and related compounds (1986)
    Chichester : Wiley-Blackwell
    Organic Magnetic Resonance 24 (1986), S. 718-722 
    Details
    ISSN: 0749-1581
    Keywords: Epoxidation induced ; 13C NMR shifts ; Lanthanide induced shifts ; Epoxides ; Alkanes ; Alkenes ; Terpenes ; Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Based on literature data, and new measurements with both simple and complicated skeletons, it is shown that epoxidation-induced shifts (EIS) usually vary by only 〈4ppm if compared with the corresponding olefins, but by 〈9 ppm if compared with the saturated analogues. Shift differences between stereoisomers (E/Z or trans/cis) are consistent and, again, similar in epoxides and olefins. Larger variations are observed only for cyclic systems in which flexibility and conformational coupling can lead to significant conformational differences between the epoxide and olefin. Yb(fod)3-induced LIS values are regular if normalized by setting the LIS for the α-carbon atoms to 100%; these and the EIS values can be used to confirm or correct13C signal assignments.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/mrc.1260240818
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  • 6
    Electronic Resource
    Electronic Resource
    185-nm Photochemistry of Olefins, Strained Hydrocarbons, and Azoalkanes in SolutionDedicated to Professor Dietrich Schulte-Frohlinde on the occasion of his 60th birthday (1986)
    Weinheim : Wiley-Blackwell
    Angewandte Chemie International Edition in English 25 (1986), S. 661-672 
    Details
    ISSN: 0570-0833
    Keywords: Photochemistry ; Azoalkanes ; Strained molecules ; Alkenes ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The possibility to excite directly at 185 nm chromophores that absorb in the vacuum-UV has stimulated increased activity during the last decade in this field of photochemistry. Whereas photochemical reactions at λ〈200 nm have been thoroughly investigated in the gas phase, only recently have intensive studies on the 185-nm photochemistry of organic compounds in solution provided new insights. Despite the high excitation energies, selective photoreactions are promoted in the short-lived singlet excited states (Rydberg photochemistry). In contrast to conventional photochemistry (λ 〉 220 nm), 185-nm irradiation preferentially results in intramolecular rearrangement, fragmentation, and isomerization reactions. Intermolecular radical couplings and abstractions as well as dimerizations (π, π*-excitation) compete minimally. Besides the straightforward denitrogenation of photoresistant (“reluctant”) azoalkanes, important applications of the short-wavelength photolysis are also found in technology (photolithography) and medicine (193-nm laser). Broadening the scope of the synthetic potential of the 185-nm photochemistry, which so far has been limited to direct cis/trans isomerizations, presents a challenge for the chemist.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/anie.198606613
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  • 7
    Electronic Resource
    Electronic Resource
    Polar Addition of Hydrogen Halides onto OlefinsThis work was supported by a grant from the National Science Foundation. (1964)
    Weinheim : Wiley-Blackwell
    Angewandte Chemie International Edition in English 3 (1964), S. 245-249 
    Details
    ISSN: 0570-0833
    Keywords: Addition ; Alkenes ; Electrophilic reactions ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Various structures have been proposed for the intermediates of electrophilic additions onto olefins; these include halonium ions, classical carbonium ions, π-complexes (i.e. nonclassical carbonium ions), and π-complexes with back-coordination. It is shown here that it is impossible to use any one of these entities alone to explain all such electrophilic additions; the electrophile itself determines the nature of the transition state formed. Polar addition of hydrogen halides onto olefins appears to proceed via a classical carbonium ion which does not occur as the free ion but as an undissociated ion pair. Various other mechanisms have been excluded by studies reported here of the stereochemical course of such additions.
    Additional Material: 2 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/anie.196402451
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  • 8
    Electronic Resource
    Electronic Resource
    Type and Extent of Isomerization of Straight-Chain Mono-olefins during the Koch Carboxylic Acid SynthesisReported in part at the meeting of the Gesellschaft Deutscher Chemiker, Aachen 1961; Angew. Chem. 73, 767 (1961). (1963)
    Weinheim : Wiley-Blackwell
    Angewandte Chemie International Edition in English 2 (1963), S. 719-722 
    Details
    ISSN: 0570-0833
    Keywords: Koch carboxylic acid synthesis ; Carboxylic acids ; Alkenes ; Isomerization ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: When straight-chain mono-olefins, from pentene to decene, are subjected to the Koch carboxylic acid synthesis by the addition of CO and H2O or CH3OH in the presence of strongly acidic catalysts, not only the expected secondary acids, but also mixtures of a specific type of tertiary acids or their methyl esters are formed. When the catalysts contain boron trifluoride, the secondary acids are formed in ratios of isomers which are, within the scope of this investigation, independent of the experimental conditions and which agree well with the values calculated from the isomer equilibria of the corresponding n-olefins. Using concentrated sulfuric acid as catalyst, a larger proportion of tertiary acids is obtained than with BF3-catalysis, and amongst the secondary acids, those isomers predominate in which the COOH group is situated near the centre of the molecule.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/anie.196307191
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  • 9
    Electronic Resource
    Electronic Resource
    Emulsion Polymerization of Vinyl Monomers under the Influence of Ionizing Radiation (1963)
    Weinheim : Wiley-Blackwell
    Angewandte Chemie International Edition in English 2 (1963), S. 295-308 
    Details
    ISSN: 0570-0833
    Keywords: Emulsion polymerization ; Polymerization ; Polymerization ; Alkenes ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Ionizing radiation induces the polymerization of some vinyl monomers in aqueous emulsion with high radiation yields. With identical emulsion compositions, the kinetics of this reaction and the kinetics of emulsion polymerization induced by water-soluble initiators are very similar. The rate of reaction in emulsion polymerization is about one hundred times greater than in bulk polymerization. The initiation of emulsion polymerization by means of ionizing radiation permits uniform “illumination” of the reacting volume, as well as almost any desired variation in the frequency of initiation during the reaction. The sharp decrease in the overall rate of reaction when initiation is interrupted during emulsion polymerization of styrene induced by γ-rays contradicts the earlier concept of sharply separated reaction zones.
    Additional Material: 11 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/anie.196302951
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  • 10
    Electronic Resource
    Electronic Resource
    Reactions of Olefins with the Titanium-Carbon BondDedicated to Prof. Dr. Karl Ziegler on the occasion of his 65th birthday (1963)
    Weinheim : Wiley-Blackwell
    Angewandte Chemie International Edition in English 2 (1963), S. 704-714 
    Details
    ISSN: 0570-0833
    Keywords: Titanium ; Alkenes ; Polymerization ; Titanium ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: At low temperatures, ethylene and α-olefins (Δ1-olefins or 1-alkenes) are rapidly converted into oligomrs by the two-component organometallic catalyst CH3TiCl3·CH3AlCl2. To achieve smooth oligomerizations, aromatic or chlorinated hydrocarbons must be used as solvents. Although the activity of the titanium-carbon bond is enhanced by the aluminum component of the catalyst, the aluminum and its methyl group do not participate in the reaction proper; the latter proceeds exclusively at the titanium-carbon bond. The reaction will olefins can be used as an analytical method for the quantitative determination of the titanium-carbon bond in admixture with the organoaluminum component. It is thus possible to follow the reaction leading to formation of the catalyst from titanium tertrachloride, as well as the processes occurring at the titanium-carbon bond during the oligomerization of olefins. All the observations indicate that the catalyst possesses an ionic structure which is determined by the solvent. It is shown that the initial reaction step probably involves formation of a complex between the olefin and the alkyltitanium cation. The reaction scheme proposed is based on organometallic reactions which are characterized by carbanion and hydride transfers within the olefin-cation complex. This mechanism, which is unusual for Ziegler catalysts, is due to the predominance of hydride transfers.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/anie.196307041
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  • 11
    Electronic Resource
    Electronic Resource
    The Oxidation of Olefins with Palladium Chloride Catalysts (1962)
    Weinheim : Wiley-Blackwell
    Angewandte Chemie International Edition in English 1 (1962), S. 80-88 
    Details
    ISSN: 0570-0833
    Keywords: Oxidation ; Palladium ; Catalysis ; Alkenes ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The oxidation of olefins to carbonyl compounds with palladium compounds, especially the oxidation of ethylene to acetaldehyde, is at present carried out on a technical scale. The reaction takes place via a palladium-olefin complex, the formation of which is inhibited by halide ions. Hydrolysis to the carbonyl compound is inhibited by hydrogen ions. The knowledge gained by studying the reaction of olefins with pure solutions of palladium salts allows important conclusions to be drawn concerning the action of technical catalyst solutions containing copper and palladium chloride.
    Additional Material: 9 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/anie.196200801
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