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  • 1985-1989  (32)
  • 1960-1964  (8)
  • 1920-1924
  • 1915-1919
  • 1820-1829
  • Alkaloids
  • Catalysis
  • 1
    Electronic Resource
    Electronic Resource
    Synthese der Hydroxypiperidinalkaloide (±)-Cassin, (±)-Spectalin, (±)-Spicigerin-methylester, der (±)-Azimsäure und (±)-Carpamsäure (1989)
    Weinheim : Wiley-Blackwell
    Liebigs Annalen 1989 (1989), S. 255-261 
    Details
    ISSN: 0170-2041
    Keywords: Alkaloids ; Piperidine alkaloids ; 3-Pyridinols; 2,6-dlialkylated ; Bromine-lithium exchange and alkylation, regiospecific ; Hydrogenation of 3-pyridinols ; Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Syntheses of the Piperidine Alkaloids (±)-Cassine, (±)-Spectaline, (±)-Spicigerine Methyl Ester and of (±)-Azimic Acid and (±)-Carpamic AcidThe piperidine alkaloids (±)-cassine (1), (±)-spectaline (2), (±)-spicigerine methyl ester (3), (±)-azimic acid (4), and (±)-carpamic acid (5) have been synthesized stereoselectively in the following way: In the SEM ether 7 of 2,6-dibromo-3-pyridinol (6) the bromine atom in position 2 can be regiospecifically exchanged with nBuLi to give 8. Reaction of 8 with methyl iodide gave the key compound 9 exclusively. In the presence of Kumada′s NidpppCl2 catalyst in ether solution 9 reacts with the Grignard reagents from the bromides 14-18 to give the products 19-23. Methanolysis of the products gave the substituted 3-pyridinol derivatives 24-28. Subsequent acetalisation led to 29, 30 and hydrolysis to 31, 32. Hydrogenation of 28-32 with Rh on alumina catalyst and 90 bar pressure gave exclusively the (±) products 33, 34, 3, 4, and 5 with (2r,3c,6c) configuration. Hydrolysis of the ethylene acetal group in 33 and 34 gave (±)-1 and (±)-2.
    Notes: Die Piperidinalkaloide (±)-Cassin (1), (±)-Spectalin (2), (±)-Spicigerin-methylester (3) sowie (±)-Azimsäure (4) und (±)-Carpamsäure (5) werden stereoselektiv synthetisiert: Im SEM-Ether 7 des 2,6-Dibromo-3-pyridinols (6) erfolgt bei der Reaktion mit nBuLi ein regiospezifischer Austausch des Bromatoms in Position 2. Die entstandene Li-Verbindung 8 läßt sich mit Methyliodid zur Schlüsselverbindung 9 methylieren. Diese reagiert in Gegenwart von Kumadas NidpppCl2-Katalysator in Ether mit den Grignard-Reagenzien aus den Bromiden 14-18 zu den 6-substituierten Pyridinen 19-23. Methanolyse und Hydrolyse liefern die 3-Pyridinol-Derivate 24-28 und durch nachfolgende Acetalisierung 29, 30 sowie durch Hydrolyse 31, 32. Die Hydrierung von 28-32 mit Rh auf Alox-Katalysator unter 90 bar Druck ergibt ausschließlich die (±)-Produkte 33, 34, 3, 4 und 5 mit (2r,3c,6c)-Konfiguration. Hydrolyse der Ethylenacetalgruppe in 33 und 34 ergibt (±)-1 und (±)-2.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jlac.198919890148
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  • 2
    Electronic Resource
    Electronic Resource
    Heteroyohimban-Analoga aus 3-Acetyl-7,12-dihydro-2-methyl-6H-indolo-[2,3-a]chinolozinium-chlorid (1989)
    Weinheim : Wiley-Blackwell
    Liebigs Annalen 1989 (1989), S. 443-447 
    Details
    ISSN: 0170-2041
    Keywords: Alkaloids ; Heteroyohimbane analogues ; Indolo[2,3-a]quinolizines ; Stilbazoles ; Aldol condensation ; Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Heteroyohimbane Analogues from 3-Acetyl-7,12-dihydro-2-methyl-6H-indolo[2,3-a]quinolizinium Chloride1)The methyl side chain of 3-Acetyl-7,12-dihydro-2-methyl-6H-indolo[2,3-a] quinolizinium chloride (1a) and its acetal 1b, prepared from tryptamine hydrochloride and acetoacetaldehyde dimethylacetal, are treated with carbonyl compounds. Starting from 1b, benzaldehyde and furfural yield the stilbazoles 4a-d, after hydrogenation of ring C the tetrahydropyridines 5a-c. With hydrate-forming carbonyl compounds like chloral, diethyl mesoxalate, and ninhydrin, water is not eliminated (6-8, 10, 12) and, starting from 1a, the acetyl side chain participates in forming the heteroyohimbane-like ring E (9, 11, 13).
    Notes: In dem aus Tryptamin-hydrochlorid und Acetylacetaldehyd-dimethylacetal gebildeten 3-Acetyl-7,12-dihydro-2-methyl-6H-indolo[2,3-a]chinolizinium-chlorid (1a) und seinem Acetal 1b wird die Methyl-Seitenkette durch Umsetzung mit Carbonyl-Verbindungen kondensiert. Benzaldehyd und Furfural führen ausgehend von 1b zu den Stilbazolen 4a-d, nach Hydrierung von Ring C zu den Tetrahydropyridinen 5a-c. Mit Hydrat-bildenden Carbonyl-Verbindungen wie Chloral, Mesoxalsäure-diethylester und Ninhydrin bleibt die Wasser-Abspaltung aus (6-8, 10, 12), und es kommt ausgehend von 1a unter Beteiligung der Acetyl-Seitenkette zur Schließung des Heteroyohimban-ähnlichen Ringes E (9, 11, 13).
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jlac.198919890178
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  • 3
    Electronic Resource
    Electronic Resource
    Intramolecular, Stoichiometric (Li, Mg, Zn) and Catalytic (Ni, Pd, Pt) Metallo-Ene Reactions in Organic Synthesis [New Synthetic Methods (75)]Dedicated to Professor Elias J. Corey on the occasion of his 60th birthday (1989)
    Weinheim : Wiley-Blackwell
    Angewandte Chemie International Edition in English 28 (1989), S. 38-52 
    Details
    ISSN: 0570-0833
    Keywords: Metallo-ene reaction ; Ene reaction ; Synthetic methods ; Catalysis ; Natural products ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Metallo-ene reactions, hardly recognized until very recently, have experienced a breathtaking development when applied in an intramolecular sense. Efficient regio- and stereoselective magnesium-ene cyclizations have served as a cornerstone for numerous syntheses of structurally diverse natural products (e.g., sesquiterpenes of marine or plant origin, alkaloids, fragrances, insect defense compounds, and a fungitoxin). A brilliant example is the synthesis of the elusive odorant (+)-khusimone which outshines 20 years of work in the field of tricyclovetivane synthesis. Palladium-, platinum-, and nickel-catalyzed versions of the metallo-ene reaction are in a comparatively early stage of exploration, but, nevertheless, reveal intriguing potential. Hence an almost 100% stereospecific C—O→C—;Pd-→ C—C chirality transfer permits simple and selective, cis- or trans-annelation processes. The mild cyclization conditions are compatible with various functional groups, such as nitrogen moieties, which offer interesting perspectives for the preparation of heterocycles (e.g., alkaloids) difficult to obtain by other methods. Carbon monoxide insertion reactions of the cyclized σ-metal intermediates were shown to afford annelated cyclopentanones and cyclopentenones with concomitant stereocontrolled formation of four carbon-carbon bonds. These and other observations, highlighted in this article, provide a platform for further extensions and applications of this powerful method in organic synthesis.
    Additional Material: 11 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/anie.198900381
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  • 4
    Electronic Resource
    Electronic Resource
    Reaction Mechanisms in Heterogeneous Catalysis; C—H Activation as a Case Study (1989)
    Weinheim : Wiley-Blackwell
    Angewandte Chemie International Edition in English 28 (1989), S. 135-145 
    Details
    ISSN: 0570-0833
    Keywords: Reaction mechanisms ; Heterogeneous catalysis ; C-H activation ; Catalysis ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Heterogeneous catalysis is changing from an empirical art to an exact science. The various methods for the analysis of solids and surfaces, constantly refined by materials science and surface science, seem to be almost unlimited. The increasing availability of atomic resolution microscopy as well as synchrotron radiation allows the characterization of catalyst particles, surface structures, surface processes and surface intermediates. We have learned to determine the surface structure sensitivity of catalytic reactions. Thermodynamic and kinetic data of catalytic reactions are now determined routinely. Isotopic exchange and labeling experiments provide information about reactant-catalyst interactions. How much have we learned through these techniques about the nature or mechanism of heterogeneously catalyzed reactions? The following article attempts to summarize the progress and the problems encountered in mechanistic studies of C—H bond formation and activation in a hydrogen atmosphere as an example for the present state of the understanding of reaction mechanisms in heterogeneous catalysis.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/anie.198901353
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  • 5
    Electronic Resource
    Electronic Resource
    Solid Ion Conductors in Heterogeneous Catalysis (1989)
    Weinheim : Wiley-Blackwell
    Angewandte Chemie International Edition in English 28 (1989), S. 708-715 
    Details
    ISSN: 0570-0833
    Keywords: Solid ion conductors ; Ion conductors ; Heterogeneous catalysis ; Conducting materials ; Catalysis ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The electrochemical measurement of oxygen activity using ion-conducting solid electrolytes (λ-sensors) has become widely known, at least since the application of three-way catalysts in the postcombustion of exhaust gases from spark-ignition engines. However, the use of solid ion conductors is not limited to control devices. There are various other potential applications and numerous problems which can be studied: the formation of oxides in the course of catalytic reactions on metal surfaces, the improvement of selectivity and yield of catalytic reactions, such as the epoxidation of ethylene on silver catalysts and, finally, the cogeneration of electrical energy during oxidation reactions, such as the partial oxidation of methanol to formaldehyde.
    Additional Material: 9 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/anie.198907081
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  • 6
    Electronic Resource
    Electronic Resource
    Cyclizations via Palladium-Catalyzed Allylic Alkylations [New Synthetic Methods (79)] (1989)
    Weinheim : Wiley-Blackwell
    Angewandte Chemie International Edition in English 28 (1989), S. 1173-1192 
    Details
    ISSN: 0570-0833
    Keywords: Cyclization ; Allylic alkylation ; Alkylation ; Synthetic methods ; Palladium ; Catalysis ; C-C coupling ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The history of ring systems in organic chemistry parallels their synthetic accessibility. Transition-metal-catalyzed cyclizations offer a new opportunity to create carbo- and heterocyclic compounds with great facility. Among these methods, allylic alkylations catalyzed by palladium have proven unusually productive because of the extraordinary chemo-, regio-, and diastereoselectivity and the continuing possibility for the development of enantioselectivity. The rules for ring closure differ from those for non-transition-metal-catalyzed reactions. A major benefit is the ability to generate medium (eight-, nine-, ten-, and eleven-membered) and large rings in preference to normal (five-, six- and seven-membered) rings. With the appropriate substrate, efficient macrocyclizations are possible under conditions of normal concentrations. A second major benefit derives from the complementary stereochemistry of the metalcatalyzed substitution (net retention of configuration) compared to non-metal-catalyzed reactions (inversion of configuration). Further, the requirement for the substrate to conform to the transition-metal template may impose a stereochemical preference in the intermediate that ultimately translates into the thermodynamically less stable organic product regardless of the stereochemistry of the starting material. While more work has focused on carbocyclic synthesis, the possibilities for heterocyclic synthesis are just beginning to be tapped. In addition to forming heterocycles by C—C bond formation, use of a heteroatom as a nucleophile has already proven effective for oxygen and nitrogen, with other nucleophiles awaiting investigation. New dimensions for cyclization via allylic alkylation arise by generating the requisite π-allylpalladium intermediates by methods other than palladium(0)-initiated allylic ionizations. In addition, metals other than palladium will clearly expand the possibilities, but as yet remain untapped.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/anie.198911731
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  • 7
    Electronic Resource
    Electronic Resource
    Natural product chemistry. Part 116. Synthesis of daurine and folidine: Two 2(1H)-quinolinone alkaloids fromHaplophyllum species (1988)
    Springer
    Monatshefte für Chemie 119 (1988), S. 1169-1178 
    Details
    ISSN: 1434-4475
    Keywords: Alkaloids ; Daurine ; Folidine ; Haplophyllum ; 2(1H)-Quinolinones ; Rutaceae ; Total synthesis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Die Strukturen der kürzlich aufgefundenen 2(1H)-Chinolinon-Alkaloide Daurin und Folidin konnten durch Totalsynthese bestätigt werden.
    Notes: Abstract Structures of the recently isolated 2(1H)-quinolinone alkaloids, daurine and folidine have been confirmed by total synthesis.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00809269
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  • 8
    Electronic Resource
    Electronic Resource
    Activation of alkynes by the dinitrogen complex [CoH(N2)(PPh 3)3] towards catalytic oligomerization and cyclization reactions (1988)
    Springer
    Monatshefte für Chemie 119 (1988), S. 583-589 
    Details
    ISSN: 1434-4475
    Keywords: Alkynes ; Catalysis ; Dinitrogen complex ; Nitriles ; Pyrimidine
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Der Komplex [CoH(N2)(PPh 3)3] katalysiert Oligomerisations- und Cyclisierungsreaktionen von Alkinen unter milden Bedingungen. Die Cyclotrimerisierung von Propinsäureethylester ergibt die drei möglichen Isomeren von Tricarbethoxybenzol; Phenylacetylen reagiert hauptsächlich zu linearen Dimeren (vor allemtrans-PhC≡CCH=CHPh) und Trimeren; lineare Dimere herrschen auch bei 3-Hexin vor, während 1-Octin (mit langer Alkylkette) vorwiegend zu 2-Octin isomerisiert wird. In allen Fällen werden ebenfalls höhere Oligomere gebildet. Außer bei Propinsäureethylester entstehen ebenfalls in geringer Menge hydrierte Dimere (z. B.trans,trans-PhCH=CHCH=CHPh aus Phenylacetylen). Eine neue Art von Cocyclisierungsreaktion mit einem Nitril (NCMe) scheint bei der Bildung (in geringer Ausbeute) von 4,6-Dimethyl-5-phenyl-pyrimidin aus Phenylacetylen vorzuliegen. Alkinole reagieren unter den Versuchsbedingungen nicht.
    Notes: Abstract The complex [CoH(N2)(PPh 3)3] catalyses oligomerization and cyclization reactions of alkynes under mild conditions. Hence, alkyne cocyclotrimerization to benzene derivatives was mainly observed for ethyl propiolate, affording the three possible isomers of tricarbethoxybenzene; phenylacetylene undergoes mainly linear dimerization totrans-PhC≡CCH=CHPh and trimerization; linear dimers are also the predominant products from 3-hexyne, but 1-octyne (with a long chain) undergoes mainly isomerization to 2-octyne; higher oligomers are also usually formed. Except for ethyl propiolate, hydrogenated dimers are detected in low yields (e.g.trans,trans-PhCH=CHCH=CHPh from phenylacetylene), whereas 3-hexene is formed in considerable yield from 3-hexyne. A novel type of cocyclization reaction with a nitrile (NCMe) appears to occur with phenylacetylene to give (although in low yield) 4,6-dimethyl-5-phenyl-pyrimidine. Alkynols are unreactive under the chosen conditions.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00809210
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  • 9
    Electronic Resource
    Electronic Resource
    Dehydrogenative condensation of monohydrosilanes yielding disilanes in the presence of platinum complex catalysts (1988)
    New York, NY [u.a.] : Wiley-Blackwell
    Applied Organometallic Chemistry 2 (1988), S. 91-92 
    Details
    ISSN: 0268-2605
    Keywords: Catalysis ; dehydrogenation ; hydrosilane ; disilane ; platinum complex ; Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Dimethylphenylsilane was catalytically dehydrogenated and condensed in the presence of platinum complexes to give 1,1,2,2-tetramethyl-1,2-diphenyl-disilane.
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/aoc.590020114
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  • 10
    Electronic Resource
    Electronic Resource
    Electron-Transfer Chain Catalysis in Organotransition Metal ChemistryDedicated to Professor Jean Tirouflet (1988)
    Weinheim : Wiley-Blackwell
    Angewandte Chemie International Edition in English 27 (1988), S. 643-660 
    Details
    ISSN: 0570-0833
    Keywords: Catalysis ; Electrocatalysis ; Chain catalysis ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Parallel to organic electrocatalysis, the field of organotransition metal electrocatalysis has developed explosively since 1980. The theoretical and experimental foundations established by Feldberg in 1971 (ECE mechanism) have been applied, using fast electrochemical techniques, to various organometallic reactions such as isomerization, ligand exchange, chelation, decomplexation, and CO insertion and extrusion. Most of the work performed to date concerns ligand exchange reactions of N-donors and P-donors in mononuclear compounds, initiated by oxidants (or anodes) and of carbonyls and P-donors in clusters, initiated by reducing agents (or cathodes). The preparative aspects of electrocatalysis have already been impressively developed in cluster chemistry and indicate that the technique is extremely useful. This review first delineates the principles and characteristics of electrocatalysis applied in organotransition metal chemistry, and then, after outlining the choice of efficient initiating reagents, goes on to describe the systems up to August 1986.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/anie.198806431
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  • 11
    Electronic Resource
    Electronic Resource
    Carbon Dioxide as an Alternative C1 Synthetic Unit: Activation by Transition-Metal Complexes (1988)
    Weinheim : Wiley-Blackwell
    Angewandte Chemie International Edition in English 27 (1988), S. 661-678 
    Details
    ISSN: 0570-0833
    Keywords: Carbon dioxide ; C1 synthetic unit ; Transition metals ; C-C coupling ; Homogeneous catalysis ; Catalysis ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The carbon dioxide molecule has been of limited importance as a synthetic unit in organic chemistry. When it is coordinated to transition metals, however, completely new possibilities arise; CO2 can bond to metal complexes in a variety of ways and can enter into insertion and coupling reactions, or become catalytically attached to other substrates. The formation of C—C bonds between carbon dioxide and unsaturated hydrocarbons under conditions of homogeneous catalysis makes available new synthetic routes to industrially interesting organic compounds.
    Additional Material: 11 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/anie.198806611
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  • 12
    Electronic Resource
    Electronic Resource
    Molecular Organometallic Chemistry on Surfaces: Reactivity of Metal Carbonyls on Metal Oxides (1988)
    Weinheim : Wiley-Blackwell
    Angewandte Chemie International Edition in English 27 (1988), S. 1127-1144 
    Details
    ISSN: 0570-0833
    Keywords: Organometallic compounds ; Surface chemistry ; Carbonyl ligands ; Metal oxides ; Catalysis ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Metal carbonyls react on metal oxide surfaces to give a wide range of structures analogous to those of known compounds. The reactions leading to formation of surface-bound metal carbonyls are explained by known molecular organometallic chemistry and the functional group chemistry of the surfaces. The reaction classes include formation of acid-base adducts as the oxygen of a carbonyl group donates an electron pair to a Lewis acidic center; nucleophilic attack at CO ligands by basic surface hydroxyl groups or O2⊖ ions; ion-pair formation by deprotonation of hydrido carbonyls to give carbonylate ions; interaction of bifunctional complexes with surface acid-base pair sites such as [Mg2⊕O2⊖]; and oxidative addition of surface hydroxyl groups to metal clusters. The reactions of surface-bound organometallic species include redox condensation and cluster formation on basic surfaces (paralleling the reactions in basic solution) as well as oxidation of mononuclear metal complexes and oxidative fragmentation of metal clusters by reaction with surface hydroxyl groups. Most supported metal carbonyls are unstable at high temperatures, but some, including osmium carbonyl cluster anions on the basic MgO surface, are strongly stabilized in the presence of CO and are precursors of catalysts for CO hydrogenation at 550 K.
    Additional Material: 18 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/anie.198811271
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  • 13
    Electronic Resource
    Electronic Resource
    High Oxidation State Organometallic Chemistry, A Challenge - the Example of RheniumSecond Essay on Organometallic Chemistry. First Essay: W. A. Herrmann, Comments Inorg. Chem. 7 (1988) 73.Dedicated to Professor Hans Bock on the occasion of his 60th birthday (1988)
    Weinheim : Wiley-Blackwell
    Angewandte Chemie International Edition in English 27 (1988), S. 1297-1313 
    Details
    ISSN: 0570-0833
    Keywords: Rhenium ; Catalysis ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Homogeneous catalysis as the major industrial outlet of organometallic basic research has been enjoying great benefit from organotransition metal species that promote bond forming between hydrocarbon fragments. Most of the commercially important processes that serve to produce large-volume organic feedstock chemicals such as linear α-olefins (Shell Higher Olefins Process), linear aldehydes (hydroformylation), acetaldehyde (Wacker-Hoechst), acetic acid (Monsanto), adiponitrile (DuPont hydrocyanation of butadiene) operate at low-valent metal centers. It is thus hardly surprising that by far the most part of organometallic research during the past few decades has been directed towards an understanding and the improvement of these catalytic reactions as well as towards the related stoichiometric chemistry. As a matter of consequence, our present knowledge on high-valent organotransition metal compound is comparatively shallow, nor do we know much about the chemical relationship and interconvertability of high and low oxidation states within a given class of compounds. In this article I want to point out some ostensibly challenging perspectives of future organometallic research by describing a novel class of high oxidation state organorhenium compounds as well as by speculating on possible generalizations for other transition metals.
    Additional Material: 18 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/anie.198812971
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  • 14
    Electronic Resource
    Electronic Resource
    Uniform Heterogeneous Catalysts: The Role of Solid-State Chemistry in their Development and DesignBased, in part, on the Hund-Klemm Lecture given at the Max Planck Institute for Solid State Research, Stuttgart (20 May 1987), and on seminars given at the Institute of Fundamental Chemistry, Kyoto (14 June, 1988), the Fritz Haber Institute of the Max-Planck-Gesellschaft, Berlin (12 March 1987), and the University of California, Berkeley (19 April 1988). (1988)
    Weinheim : Wiley-Blackwell
    Angewandte Chemie International Edition in English 27 (1988), S. 1673-1691 
    Details
    ISSN: 0570-0833
    Keywords: Heterogeneous catalysis ; Solid-state reactions ; Catalysis ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Heterogeneous catalysts are generally assumed to be multiphasic and multicomponent; many of them are, and this is one of the resons why disentangling the factors that govern their mode of action is so difficult. But there is a large class of heterogeneous catalysts where the solid is monophasic and where the activity may be envisaged as being dispersed in a spatially uniform fashion throughout its bulk. This is true both of zeolites and many other microporous catalysts on the one hand, and of certain mixed metal oxides, where the non-stoiohiometry is inextricably mingled with the catalysis, on the other. By recognizing this broad classification numerous operational advantages follow: the performance of existing catalysts and the design of those yet to be prepared can be placed on a rational footing; moreover, the myriad techniques of solid-state chemistry and physics, often regarded as inapplicable to the subtle and special problems of surface chemistry, are seen to be of direct relevance as probes for the structure and properties of proven uniform heterogeneous catalysts as well as for the synthesis and development of new ones. This review, which draws analogies with and lessons from the chemistry of enzyme catalysts, focuses largely on the catalytic conversions of hydrocarbons over zeolites, clays, microporous AlPO4 and a wide range of metal oxides.
    Additional Material: 32 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/anie.198816731
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  • 15
    Electronic Resource
    Electronic Resource
    Zeolites: Catalysts for Organic SynthesesDedicated to Professor Helmut Dörfel on the occasion of his 60th birthday (1988)
    Weinheim : Wiley-Blackwell
    Angewandte Chemie International Edition in English 27 (1988), S. 226-246 
    Details
    ISSN: 0570-0833
    Keywords: Zeolites ; Catalysis ; Synthetic methods ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Zeolites have proved to be valuable technical catalysts in petrochemistry and in oil processing. The characteristic properties of zeolites, such as acidity, shape-selectivity and thermal stability also enable them to be used for highly selective synthesis in the fields of chemical intermediates and fine chemicals. This interesting area of application has grown continuously in recent years. The present article summarizes the various standard types of reaction involved in organic syntheses which can be catalyzed by zeolites; these include, inter alia, electrophilic and nucleophilic substitution reactions, isomerization of double bonds and carbon skeletons, as well as addition, elimination and hydrogenation reactions.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/anie.198802261
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  • 16
    Electronic Resource
    Electronic Resource
    Contributions to Organo-Nickel ChemistryIncluding unpublished results by A. Aradi, O. Behrens, H. Kuhn, T. Leven, J. Neuffer, J. Monkiewicz, K. R. Pörschke, L. Stehling, and K. H. Walter and unpublished crystal structure determinations by C. Krüger, E. Raabe, and Y.-H. Tsay, and model calculations by K. Angermund. The preceding page shows Figure 19 of this article. (1988)
    Weinheim : Wiley-Blackwell
    Angewandte Chemie International Edition in English 27 (1988), S. 185-206 
    Details
    ISSN: 0570-0833
    Keywords: Organonickel compounds ; Polymerization ; Hydrogenation ; Homogeneous catalysis ; Catalysis ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: One hundred years of organonickel chemistry have generated a wealth of new knowledge and a history of examples of accidental discoveries which have finally led to industrial applications. The historical development is associated with the names of Mond, Sabatier, Reppe and Ziegler and, with the methods and techniques available today, many of the original discoveries and unsolved problems are attracting renewed attention. For example, 70 years were to go by before a synthesis first conceived by Sabatier could finally be realized. The path leading from nickel-catalyzed hydrogenation to highly enantioselective homogeneous catalysts is one of the contributions to organonickel chemistry which is described here.
    Additional Material: 19 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/anie.198801851
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    Some adaptations in the method of the ‘Pharmacopoeia Helvetica Editio Sixta’ for the determination of total alkaloids in Strychnos seeds (1987)
    Springer
    Pharmacy world & science 9 (1987), S. 324-325 
    Details
    ISSN: 1573-739X
    Keywords: Alkaloids ; Extraction ; Pharmacopoeias ; Strychnos
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01956513
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  • 18
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    Catalysis of hydrosilylation XIII.Partly presented at the 7th International Symposium on Organosilicon Chemistry, ‘Organosilicon Chemistry Directed to Practical Use’, Sept. 18-20, 1984, Kiryu, Japan. The lecture 202, Part XII, J. Organometal. Chem. is accepted for publication. Gas-phase hydrosilylation of acetylene by trichlorosilane on functionalised silica supported rhodium and ruthenium phosphine complexes (1987)
    New York, NY [u.a.] : Wiley-Blackwell
    Applied Organometallic Chemistry 1 (1987), S. 267-273 
    Details
    ISSN: 0268-2605
    Keywords: Hydrosilylation ; Acetylene ; Trichlorosilane ; Silica ; Rhodium ; Ruthenium ; Catalysis ; Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Gas-phase hydrosilylation of acetylene by tri-chlorosilane catalyzed in a continuous flow apparatus by rhodium and ruthenium phosphine complexes immobilized on the silica via mercapto, phosphine, amine and nitrile ligands has been studied. GLC analysis of the reaction products showed vinyltrichlorosilane to be accompanied by products of double hydrosilylation of acetylene and the redistribution of trichlorosilane followed by the hydrosilylation and hydrogenative hydrosilylation of acetylene with dichlorosilane. A scheme for this complex competitive-consecutive reaction was proposed. The yield and selectivity of vinyltrichlorosilane can be much improved under special reaction conditions, e.g. rate flow of the particular substrates, temperature, given catalyst and others. Kinetic measurements carried out in the range of 115-140°C allowed us to evaluate the activation energy, Ea, for the vinyltrichlorosilane synthesis, which varied between 20.5 and 27.6 kJ mol-1 for the selected rhodium and ruthenium supported complexes.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/aoc.590010309
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  • 19
    Electronic Resource
    Electronic Resource
    Directed Homogeneous Hydrogenation [New Synthetic Methods (65)] (1987)
    Weinheim : Wiley-Blackwell
    Angewandte Chemie International Edition in English 26 (1987), S. 190-203 
    Details
    ISSN: 0570-0833
    Keywords: Homogeneous hydrogenation ; Hydrogenation ; Synthetic methods ; Catalysis ; Stereoselectivity ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Stereochemical control is a major concern in the application of homogeneous catalysis to organic chemistry. In this context, the directed hydrogenation of olefins employing cationic rhodium or iridium catalysts has considerable potential, for very high selectivity can be attained under mild reaction conditions. The only requirement is a polar functional group in proximity to the double-bond which remains bound to the metal during the catalytic cycle and thereby controls the Stereochemical course of hydrogen delivery through the constraints of chelation. The substituent is most frequently a hydroxy group OH but can also be an ester, amide or carbamate group; other groups remain to be scrutinized. In cyclic compounds, directed hydrogenation can lead to face-selectivity, and the polar substituent may be in the β-, γ-, or δ-position to the double-bond. Acyclic stereoselection ensues with β- or γ-substituents in appropriate compounds, and the configuration of reduced product is predictable on the basis of simple rules. The application of optically active rhodium complexes leads to useful kinetic resolution procedures.
    Additional Material: 12 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/anie.198701901
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  • 20
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    Emission of Microparticles from Automotive Sources - X-ray Photoelectron Spectroscopy in Environmental Analysis (1987)
    Weinheim : Wiley-Blackwell
    Angewandte Chemie International Edition in English 26 (1987), S. 309-319 
    Details
    ISSN: 0570-0833
    Keywords: EPR spectroscopy ; Automotive microparticle sources ; X-ray photoelectron spectroscopy ; Environmental chemistry ; Catalysis ; Photoelectron spectroscopy ; Microparticles ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: In the last fifteen years the necessity for efficient environmental protection has become generally accepted. However, before practical measures can be taken, a comprehensive assessment of the present environmental situation should be made, taking into consideration the risks involved in as well as the positive effects of any planned environmental changes - whether natural or man made. This clearly calls for close cooperation between the various scientific disciplines. For example, the treatment of exhaust fumes from motor vehicles has been of primary importance in measures taken to restrict the recent damage caused to woodland areas. The introduction of 3-Way-Catalyst technology has been regarded as a viable countermeasure. The following report is intended to describe a method for examining some side effects of catalyst usage. Accordingly, the chemical composition of microparticles emitted from combustion motors through the use of catalysts will be examined and some possible changes in the environment caused by such particles will be briefly considered. As in the area of research into catalysts for industrial synthesis a knowledge of the surface structure of such particles, i.e. the boundary layer between emission product and environment, is necessary in the investigation into their effects. Consequently, a surface sensitive technique from solid state physics, X-ray photoelectron spectroscopy (XPS or ESCA) has found novel use in the area of environmental analysis. In the following report emphasis will be placed on the description of measurement techniques and the interpretation of the results obtained. After a critical consideration of the experimental methods, examples from two different series of measurements on diesel and Otto motors equipped with soot filters or 3-way-catalysts respectively, will be given. Hopefully, this report will also stimulate establishment of the use of EPS in environmental research techniques.
    Additional Material: 17 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/anie.198703091
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  • 21
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    Metal catalysed Brooke rearrangement of 3-Halo-1-(trimethylsilyl) propan-2-one (Halo = Cl or Br) (1987)
    New York, NY [u.a.] : Wiley-Blackwell
    Applied Organometallic Chemistry 1 (1987), S. 281-284 
    Details
    ISSN: 0268-2605
    Keywords: Catalysis ; Brooke rearrangment ; Iridium ; Palladium ; Platinum ; Complexes ; Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The complexes [IrH(CO)(PPh3)3], trans-[IrCI(CO)- (PPh3)2], [RhH(PPh3)4], [Pd(PPh3)4], [Pt(trans-stilbene)(PPh3)2] and [Pt(η3-CH2-COCH2)-(PPh3)2] catalyse the rearrangement of Me3SiCH2C(O)CH2Cl to CH2=C(OSiMe3)-CH2Cl.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/aoc.590010311
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  • 22
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    Silica anchored bis(trialkylphosphine) platinum oxalate. A photogenerated catalyst for olefin hydrosilation (1986)
    Springer
    Monatshefte für Chemie 117 (1986), S. 617-619 
    Details
    ISSN: 1434-4475
    Keywords: Catalysis ; Photochemistry ; Supported platinum complex
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Die Ultraviolettbetrahlung des siliziumverknüpften Komplexes Pt(C2O4)L 2 [L=(H3CO)3Si(CH2)2PEt 2] ergab eine [SiO2]-L 2Pt-Spezies, die die Hydrosilierung von Olefinen katalysiert oder unter Bildung eines Oberflächen-Dicarbonylkomplexes 2 CO addiert.
    Notes: Abstract Ultraviolet irradiation of the silica attached complex Pt(C2O4)L 2, [L=(H3CO)3Si(CH2)2PEt 2], yields a [SiO2]-L 2Pt species that catalyzes olefin hydrosilation or adds 2 CO to yield a surface dicarbonyl complex.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00817899
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  • 23
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    Study on the reactions of the dinitrogen complexestrans-[M(N2)2(Ph 2PCH2CH2PPh 2)2] (M=Mo or W) with ethyldiazoacetate: Formation of an Azo compound and of a phosphazene species (1986)
    Springer
    Monatshefte für Chemie 117 (1986), S. 429-435 
    Details
    ISSN: 1434-4475
    Keywords: Catalysis ; Dinitrogen complexes ; Ethyldiazoacetate
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Die Komplexetrans-[Mo(N2)2(dppe)2] (dppe=Ph 2PCH2CH2PPh 2) reagieren mit NN=CHCOOEt in benzolischer Lösung zuPh-N=N-CH3 als organischem Hauptprodukt. Andererseits wird bei der Bestrahlung vontrans-[W(N2)2(dppe)2] inTHF-Lösung in der Gegenwart von Ethyldiazoacetat das PhosphazenPh 2P(N2CHCOOEt)(CH2CH2)P(N2CHCOOEt)Ph 2 gebildet; in feuchter Lösung erleidet die Phosphazen-Bindung eine teilweise Hydrolyse und die Phosphonium-Spezies [Ph 2P(NHNCHCOOEt)(CH2CH2)P(NHNCHCOOEt)Ph 2]2+ scheint gebildet zu werden.
    Notes: Abstract Complextrans-[Mo(N2)2(dppe)2] (dppe=Ph 2PCH2CH2PPh 2) reacts with NN=CHCOOEt in benzene solution to afford benzene-azomethane,Ph-N=N-CH3, as the main organic product. However, the phosphazene speciesPh 2P(N2CHCOOEt)(CH2CH2)P(N2CHCOOEt)Ph 2 is formed by irradiating aTHF solution oftrans-[W(N2)2(dppe)2] in the presence of ethyldiazoacetate; in moist solution, the phosphazene bonds undergo a partial hydrolysis, and the phosphonium species [Ph 2P(NHNCHCOOEt)(CH2CH2)P(NHNCHCOOEt)Ph 2]2+ appears to be formed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00810890
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    Lespedeza phenolics andPenstemon alkaloids: Effects on digestion efficiencies and growth of voles (1986)
    Springer
    Journal of chemical ecology 12 (1986), S. 713-728 
    Details
    ISSN: 1573-1561
    Keywords: Alkaloids ; phenolics ; feeding trials ; digestibility ; growth ; Lespedeza cuneata ; Penstemon digitalis ; Microtus pennsylvanicus ; Microtus ochrogaster
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Lespedeza cuneata contains high levels of phenolics and is a common food plant of the meadow vole (Microtus pennsylvanicus);Penstemon digitalis contains substantial quantities of alkaloids and is a common food plant of meadow voles and prairie voles (M. ochrogaster). We investigated the palatability of these plants and the effects of their secondary compounds on the digestion efficiencies and growth of both species of voles. Voles ate very little of either plant when alternative food was present. Phenolics and alkaloids were extracted from the plants, incorporated into separate artificial diets, and fed to weanling voles for three weeks.Lespedeza phenolics reduced the growth of meadow voles but not prairie voles throughout the feeding trial. These compounds disrupted digestion, reducing protein digestibility by more than half.Penstemon alkaloids lowered only the initial growth rates of prairie voles and had no significant effect on meadow voles. Prairie voles tended to increase food consumption rates on bothLespedeza andPenstemon diets. This response offset some of the decrease in digested protein intake in the first case, and offset the increased metabolic cost of processing the diet in the latter case. Our results indicate that althoughLespedeza phenolics andPenstemon alkaloids do influence consumption and digestibility of artificial diets, they do not greatly reduce the performance (i.e., growth or survival) of voles when consumed at levels generally observed for wild voles. However, these compounds probably do place an upper limit on the amount of freshLespedeza andPenstemon that can be consumed and contribute to the generalist feeding strategy of voles.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01012104
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  • 25
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    New constituents of Zanthoxylum tessmannii(Engl.) Ayafor root (1986)
    Weinheim : Wiley-Blackwell
    Journal of High Resolution Chromatography 9 (1986), S. 412-414 
    Details
    ISSN: 0935-6304
    Keywords: Gas chromatography ; Capillary columns ; Zanthoxylum tessmannii (Engl.) Ayafor ; Amides ; Terpene hydrocarbons ; Alkaloids ; Medicinal plant ; Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jhrc.1240090712
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  • 26
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    A Receptor-Mediated Pathway for Cholesterol Homeostasis (Nobel Lecture)Copyright © The Nobel Foundation 1986. - We thank the Nobel Foundation, Stockholm, for permission to print this article. (1986)
    Weinheim : Wiley-Blackwell
    Angewandte Chemie International Edition in English 25 (1986), S. 583-602 
    Details
    ISSN: 0570-0833
    Keywords: Cholesterol homeostasis ; Receptors ; Catalysis ; Nobel lecture ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 16 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/anie.198605833
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  • 27
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    The Palladium-Catalyzed Cross-Coupling Reactions of Organotin Reagents with Organic Electrophiles [New Synthetic Methods (58)] (1986)
    Weinheim : Wiley-Blackwell
    Angewandte Chemie International Edition in English 25 (1986), S. 508-524 
    Details
    ISSN: 0570-0833
    Keywords: Cross-coupling ; Organotin compounds ; Electrophilicity ; Palladium ; Catalysis ; C-C coupling ; Synthetic methods ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The cross-coupling of organotin reagents with a variety of organic electrophiles, catalyzed by palladium, provides a novel method for generating a carbon-carbon bond. Because this mild, versatile reaction is tolerant of a wide variety of functional groups on either coupling partner, is stereospecific and regioselective, and gives high yields of product, it is ideal for use in the synthesis of elaborate organic molecules. When the coupling reaction is carried out in the presence of carbon monoxide, instead of a direct coupling, carbon monoxide insertion takes place, stitching the two coupling partners together and generating a ketone.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/anie.198605081
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  • 28
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    Hydroxide Ion Initiated Reactions Under Phase Transfer Catalysis Conditions: Mechanism and Implications. New Synthetic Methods (62) (1986)
    Weinheim : Wiley-Blackwell
    Angewandte Chemie International Edition in English 25 (1986), S. 960-970 
    Details
    ISSN: 0570-0833
    Keywords: Phase-transfer catalysis ; Catalysis ; Synthetic methods ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The development of Phase Transfer Catalysis (PTC) represents a major step forward in the employment of many organic reactions and renders them very convenient and useful processes. These reactions involve the application of nucleophiles in general, anions and bases in particular, in reactions carried out in a water-organic solvent system. They can be performed both in the laboratory and on an industrial scale. The ease of application of PTC processes is the main reason for their increasing utilization in industry. An outstanding achievement of this technique is the employment of aqueous bases in reactions which traditionally would otherwise require a strong base in a nonaqueous medium. The classical procedures that require severe anhydrous conditions, expensive solvents and dangerous bases such as metal hydrides and organometallic reagents are now replaced by aqueous solutions of, e.g., sodium or potassium hydroxides (PTC/OH processes). In contrast to the extensive synthetic applications of PTC/OH systems, the detailed mechanisms of these processes have been the subject of a great deal of controversy and various mechanisms have been suggested. However, it would seem that our knowledge concerning the mechanistic aspects of such reactions has now reached the stage where it can be used to advantage in synthesis planning. A better understanding of the various factors which influence the reaction would undoubtedly help to optimize PTC/OH processes such as to enable higher yields in shorter reaction times at lower temperatures. The importance of, inter alia, the catalyst will be pointed out and it is highly recommended that such catalysts be always available in the laboratory, for the range of organic reactions that they can efficiently, conveniently and safely catalyze is vast indeed.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/anie.198609601
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  • 29
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    Steroidal glycoalkaloid content of potato, tomato and their somatic hybrids (1985)
    Springer
    Theoretical and applied genetics 70 (1985), S. 655-660 
    Details
    ISSN: 1432-2242
    Keywords: Solarium tuberosum ; Lycopersicon esculentum ; Protoplast fusion ; Pomato ; Topato ; Alkaloids
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Analyses of leaves and ‘tubers’ from somatic hybrids of potato and tomato (‘pomato’ with plastids of potato, ‘topato’ with plastids of tomato) produced by fusion of protoplasts from liquid cultures of dihaploid potato and mesophyll of tomato revealed the presence of the two major potato glycoalkaloids (α-solanine and α-chaconine) as well as the tomato glycoalkaloid (αtomatine). The total alkaloid content of leaves was greater than that of ‘tubers’ and similar to levels in the foliage of parent plants. However, glycoalkaloids were more abundant in hybrid ‘tubers’ than in normal potato tubers by a factor of 5–15. In hybrid foliage, approximately 98% of the alkaloid present was of potato origin whereas in ‘tubers’ the reverse was the case, with tomatine comprising 60–70% of the total alkaloid. The similarities in alkaloid content and ratios between the pomato and the topato lines indicate that plastomes do not influence the biosynthesis and distribution of these alkaloids. The results indicate that major secondary metabolites may prove useful for assessing the hybrid nature of such plants.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00252292
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    Organocobalt Compounds in the Synthesis of Pyridines-An Example of Structure-Effectivity Relationships in Homogeneous CatalýsisBased on the work of Helmut Bönnemann, Werner Brijoux, Rainer Brinkmann, Willi Meurers, Michael Radermacher, and Stephan Wendel. The author thanks his co-workers for their important contributions to this work.Dedicated to Professor Günther Wilke on the occasion of his 60th bithday (1985)
    Weinheim : Wiley-Blackwell
    Angewandte Chemie International Edition in English 24 (1985), S. 248-262 
    Details
    ISSN: 0570-0833
    Keywords: Organocobalt compounds ; Pyridines ; Catalysis ; Homogeneous catalysis ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The cocyclization of alkynes with cyano compounds using organocobalt catalysts of the type [YCoL] has evolved into a versatile and technically useful method for synthesizing pyridine and its derivatives. An important advance came with the realization that the organo group Y remains attached to the cobalt throughout the catalytic cycle. This opened up the possibility of optimizing the catalyst by varying the controlling ligand Y.
    Additional Material: 11 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/anie.198502481
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    Catalytic Synthesis of Organolithium and Organomagnesium Compounds and of Lithium and Magnesium Hydrides - Applications in Organic Synthesis and Hydrogen StorageBased on work carried out by Ekkehard Bartmann, Borislav Bogdanović, Alexis Cordi, Gudrun Koppetsch, Oleg Kuzmin, Shih-tsien Liao, Paolo Locatelli, Meenakshi Maruthamuthu, Klaus Schlichte, Manfred Schwickardi, Peter Sikorsky, Bernd Spliethoff, Halszka Stepowska, Bernd Wermeckes, Uwe Westeppe, and Ursula Wilczok. The author thanks these co-workers for their dedicated and enthusiastic assistance.Dedicated to Professor Günther Wilke on the occasion of his 60th bithday (1985)
    Weinheim : Wiley-Blackwell
    Angewandte Chemie International Edition in English 24 (1985), S. 262-273 
    Details
    ISSN: 0570-0833
    Keywords: Organomagnesium compounds ; Magnesium hydrides ; Hydrides ; Hydrogen storage ; Catalysis ; Organolithium compounds ; Lithium hydrides ; Energy storage ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A recent development in homogeneous catalysis is the discovery of catalysts that are active for the lithiation of 1-alkenes to alkenyllithium compounds and lithium hydride as well as for the hydrogenation of lithium and magnesium under mild conditions. The catalytically prepared magnesium hydride is highly reactive and adds to 1-alkenes to give diorganomagnesium compounds and can also be used in the preparation of, for example, silane and “active” magnesium. The use of metal hydrides in hydrogen storage is discussed: hydrogenation/dehydrogenation experiments show that the catalytically prepared magnesium hydride (which can be doped with a second metal) can be used as a high-temperature hydrogen storage material.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/anie.198502621
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    η3-Allylpalladium CompoundsBased on work carried out by B. Henc, P. W. Jolly, T. Joswig, B. Raspel, G. Schenker, K. P. Schick, and H. Trinh.Dedicated to Professor Günther Wilke on the occasion of his 60th bithday (1985)
    Weinheim : Wiley-Blackwell
    Angewandte Chemie International Edition in English 24 (1985), S. 283-295 
    Details
    ISSN: 0570-0833
    Keywords: Allylpalladium compounds ; Palladium ; Catalysis ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The use of transition-metal complexes as homogeneous catalysts for the production of organic chemicals is of considerable industrial significance. Although palladium complexes have not attained the same importance as, for example, those of rhodium or cobalt, palladium is nonetheless one of the most versatile metals for synthetic organic purposes. An understanding of the role played by the metal in these reactions is essential for their optimal utilization. This necessarily entails a detailed study of the chemistry of the palladium-carbon bond. In this article we concentrate on η3-allylpalladium complexes, which are frequently involved as intermediates in the Pd-catalyzed transformations of dienes. The study of their behavior gives a deeper insight into the individual steps of a catalytic cycle.
    Additional Material: 12 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/anie.198502831
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    Oxidative Condensation of Quaternary Phenolic BasesBased on lectures delivered at the International Symposium on Organic Chemistry held by the Societé Chimique de Belgique in Brussels, June 15th, 1962, the XIXth IUPAC Congress in London, July 11th, 1963, a Gordon Research Conference in New Hampton, August 2nd, 1963, and at several American universities and research institutes.Dedicated to Prof Dr. H. Brockmann on the occasion of his 60th birthday (1964)
    Weinheim : Wiley-Blackwell
    Angewandte Chemie International Edition in English 3 (1964), S. 192-200 
    Details
    ISSN: 0570-0833
    Keywords: Phenolic bases ; Alkaloids ; Condensation ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Provided they contain quaternary nitrogen, simple phenolic bases can undergo oxidative condensation under conditions similar to those of biogenesis to form alkaloids of the isoquinoline series with good yields. By means of such oxidative condensations, more than sixty alkaloids of various structural types have become more easily obtainable. Of the numerous possible condensations of the intermediate mesomeric radicals only those which lead to naturally occurring alkaloids give good yields and few by-products. The results suggest that oxidative condensations of quaternary bases are also involved in the biosynthesis of alkaloids in the plant cell.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/anie.196401921
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    Proton Transfer, Acid-Base Catalysis, and Enzymatic Hydrolysis. Part I: ELEMENTARY PROCESSESPart II (Catalytic Mechanisms) will appear shortly in this journal.Dedicated to Dr. W. Foerst on the occasion of his 65th birthday (1964)
    Weinheim : Wiley-Blackwell
    Angewandte Chemie International Edition in English 3 (1964), S. 1-19 
    Details
    ISSN: 0570-0833
    Keywords: Proton transfer ; Catalysis ; Enzyme catalysis ; Hydrolysis ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The proton occupies a special position as a promoter and mediator in chemical reactions occurring in solution. Many reactions in organic chemistry are catalysed by acids or bases; likewise, most enzymes contain active groups which promote acid-base catalysis. To understand the reaction mechanisms involved, it is necessary to identify the elementary steps as well as their course in time. Systematic investigation of these elementary steps as well as their course in time. Systematic investigation of these elementary steps has become possible only with the development of new methods for studying very fast reactions. The present paper reviews the information obtained in this type of investigation. The result is a relatively complete picture of the elementary proton transfer mechanisms and a comprehensive description of the modes and laws of acid-base and enzymatic catalysis.
    Additional Material: 12 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/anie.196400011
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    The Mechanism of the Action of Organometallic CatalystsDedicated to Prof. Dr. Karl Winnacker on the occasion of his 60th birthday. (1964)
    Weinheim : Wiley-Blackwell
    Angewandte Chemie International Edition in English 3 (1964), S. 93-101 
    Details
    ISSN: 0570-0833
    Keywords: Organometallic catalysts ; Catalysis ; Reaction mechanisms ; Lithium ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Kinetic investigations of the polyreaction of isoprene with organolithium compounds as initiators in n-heptane as solvent indicate the following sequence of reactions: 1. formation of an adduct between a monomeric form of the organolithium compound and the isoprene and 2. reaction of this adduct with an associated form of the organolithium compound with insertion of the isoprene. The adduct formation is considered to be due to chemisorption, and proof of such chemisorption of a monomer (ethylene) is also demonstrated for a homogeneous Ziegler-type catalyst. All the reactions can be formulated in the form of cyclic structures with electron-deficient character. Postulation of such ring structures explains the surprising values obtained for the frequency factors and equilibrium constants.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/anie.196400931
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    Coordination Chemistry and Catalysis. Investigations on the Synthesis of Cyclooctatetraene by the Method of W. Reppe (1964)
    Weinheim : Wiley-Blackwell
    Angewandte Chemie International Edition in English 3 (1964), S. 185-191 
    Details
    ISSN: 0570-0833
    Keywords: Coordination modes ; Catalysis ; Cyclooctatetraenes ; Reppe chemistry ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The relationship between the structure and the catalytic activity of nickel(II) complexes in the synthesis of cyclooctatetraene by the method of W. Reppe is discussed. The cyclotetramerization of acetylene takes place within labile Ni(II)-acetylene π-complexes. Inhibition tests have made it probable that four molecules of acetylene are grouped around the nickel ion in the transition state, in a configuration which favors the formation of the eight-membered ring.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/anie.196401851
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    The Biosynthesis of Alkaloids IIPart I of this review appeared in Angew. Chem. Internet. Edit. 2, 341 (1963). (1963)
    Weinheim : Wiley-Blackwell
    Angewandte Chemie International Edition in English 2 (1963), S. 441-458 
    Details
    ISSN: 0570-0833
    Keywords: Biosynthesis ; Alkaloids ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/anie.196304411
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    The Biogenesis of Ergot AlkaloidsDedicated to Professor Hans von Euler on the occasion of his 90th birthday (1963)
    Weinheim : Wiley-Blackwell
    Angewandte Chemie International Edition in English 2 (1963), S. 243-247 
    Details
    ISSN: 0570-0833
    Keywords: Ergot alkaloids ; Alkaloids ; Biosynthesis ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: In this article the biogenesis of the ergoline ring in lysergic acid derivatives and the clavines is discussed. T·yptophan and mevalonic acid are the precursors. The N-methyl group is supplied by formate or methionine. Concepts and results dealing with the manner in which the compounds are formed are discussed. Finally, the known biogenetic relationships among the ergot alkaloids are discussed in connection with their biogenesis.
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/anie.196302431
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  • 39
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    The Biosynthesis of Alkaloids IPart II of this review will appear in a subsequent issue of this journal.Dedicated to Professor Dr. Adolf Butenandt on the occasion of his 60th birthday (1963)
    Weinheim : Wiley-Blackwell
    Angewandte Chemie International Edition in English 2 (1963), S. 341-357 
    Details
    ISSN: 0570-0833
    Keywords: Biosynthesis ; Alkaloids ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/anie.196303411
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    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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