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Copyright of Angewandte Chemie is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Angewandte Chemie is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Angewandte Chemie is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Organocatalysts promote a range of C−N bond forming reactions of amines with CO2. Herein, we review these reactions and attempt to identify the unifying features of the catalysts that allows them to promote a multitude of seemingly unrelated reactions. Analysis of the literature shows that these reactions predominantly proceed by carbamate salt formation in the form [BaseH][RR′NCOO]. The anion of the carbamate salt acts as a nucleophile in hydrosilane reductions of CO2, internal cyclization reactions or after dehydration as an electrophile in the synthesis of urea derivatives. The reactions are enhanced by polar aprotic solvents and can be either promoted or hindered by H‐bonding interactions. The predominant role of all types of organic and salt catalysts (including ionic liquids, ILs) is the stabilization of the carbamate salt, mostly by acting as a base. Catalytic enhancement depends on the combination of the amine, the base strength, the solvent, steric factors, ion pairing and H‐bonding. A linear relationship between the base strength and the reaction yield has been demonstrated with IL catalysts in the synthesis of formamides and quinazoline‐2,4‐diones. The role of organocatalysts in the reactions indicates that all bases of sufficient strength should be able to catalyze the reactions. However, a physical limit to the extent of a purely base catalyzed reaction mechanism should exist, which needs to be identified, understood and overcome by synergistic or alternative methods. [ABSTRACT FROM AUTHOR]

Ein Fest der Wissenschaft inmitten der Natur: Die 54. Das macht die Bürgerstock-Konferenz besonders attraktiv für Chemiker mit breitem wissenschaftlichen Interesse, die die Grenzen der Molekularwissenschaften außerhalb der "Komfortzone" ihrer jeweiligen Fachgebiete erkunden wollen. Prof. Chen erläuterte die verschiedenen Möglichkeiten der Manipulation der Proteinfunktion, darunter die Erweiterung des genetischen Codes zur Einführung molekularer "Griffe"[6] und bioorthogonaler "Klick"-Reaktionen für deren Derivatisierung.[7] Chen erläuterte weiter wie diese, um einzelne Proteine in einer Zelle zu untersuchen, einzeln aktiviert werden müssen.[8] Zu diesem Zwecke hat die Chen-Gruppe bioorthogonale Spaltprotokolle (Deprotektion) zur "Rettung" oder "Befreiung" ruhender Enzyme entwickelt. Costas erläuterte die Strategien zur Abstimmung der elektronischen Eigenschaften in seinen Eisenkatalysatoren sowie die Rolle von Carbonsäuren und Peptiden als Additive für die Modulation der zweiten Koordinationssphäre der Eisenkomplexe.[84] Er stellte auch einige neuere Anwendungen dieser Systeme für die ##C-H-Bindungsoxidation vor, zusammen mit Ansätzen zur Anpassung der Positionsselektivität des Katalysators. [Extracted from the article]

Copyright of Angewandte Chemie is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract: Analysis of the chemical‐organic knowledge represented as a giant network reveals that it contains millions of reaction sequences closing into cycles. Without realizing it, independent chemists working at different times have jointly created examples of cyclic sequences that allow for the recovery of useful reagents and for the autoamplification of synthetically important molecules, those that mimic biological cycles, and those that can be operated one‐pot. [ABSTRACT FROM AUTHOR]

To mark the 100th birthday of R. B. Woodward (April 10, 1917-July 8, 1979), a discussion and analysis of Woodward's persona is given. The fundamental theme is that 'Woodward experienced his own exceptionality,' as described by Albert Eschenmoser, Woodward's partner in the vitamin B12 project. Woodward's rock star personality is explored and discussed as one of his legacies in addition to his scientific achievements. Woodward presented himself to his students, colleagues, and fellow chemists with an aura of nobility and romanticism. [ABSTRACT FROM AUTHOR]

Copyright of Angewandte Chemie is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Octulene, the higher homologue of kekulene and septulene, was synthesized using the fold-in method. This new hydrocarbon macrocycle contains a large 24-membered inner circuit, which is peripherally fused to 24 benzene rings. Such an arrangement produces considerable hyperbolic distortion of the π-conjugated surface. The consequences of distortion in octulene were explored using photophysical methods, which revealed a reduced electronic band gap and greater flexibility of the π system. Octulene contains a functional cavity with a diameter larger than 5.5 Å that is capable of efficiently binding the chloride anion in a nonpolar solvent ( Ka= 2.2(4)×104 m−1, 1 % dichloromethane (DCM) in benzene). The octulene-chloride interaction is stabilized by eight weak C(sp2)H⋅⋅⋅Cl bonds, providing the first example of a hydrocarbon-based anion receptor. [ABSTRACT FROM AUTHOR]

Copyright of Angewandte Chemie is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Angewandte Chemie is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Angewandte Chemie is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Angewandte Chemie is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Angewandte Chemie is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Angewandte Chemie is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The current state of affairs in the drug discovery and development process is briefly summarized and then ways to take advantage of the ever-increasing fundamental knowledge and technical knowhow in chemistry and biology and related disciplines are discussed. The primary motivation of this Essay is to celebrate the great achievements of chemistry, biology, and medicine and to inform and inspire students and academics to enter the field of drug discovery and development while, at the same time, continue to advance the fundamentals of their disciplines. It is also meant to encourage and catalyze multidisciplinary partnerships between academia and industry as scientists attempt to merge their often complementary interests and expertise to achieve new improvements and breakthroughs in their respective fields, and the common goal of applying them to the discovery and invention of new and better medicines, especially in areas of unmet needs. [ABSTRACT FROM AUTHOR]

Copyright of Angewandte Chemie is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Angewandte Chemie is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Angewandte Chemie is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Hybridstrukturen zwischen den bekannten Phthalocyanin ‐ und Porphyringerüsten waren bisher außerordentlich schwer synthetisierbar. Eine einfache, effiziente Synthese von meso ‐ derivatisierten Tetrabenzotriazaporphyrinen (siehe Schema) wird beschrieben, die einen bequemen Zugang zu dieser unterentwickelten Materialklasse eröffnen. [ABSTRACT FROM AUTHOR]

Selektives Erhitzen oder Überhitzen? Die Verstärkungseffekte, die Dudley und Mitarbeiter in der mikrowellenunterstützten Friedel ‐ Crafts ‐ Alkylierung sehen (siehe Bild), sind auf ein Überhitzen des gesamten Reaktionsgemischs zurückzuführen, nicht etwa auf ein selektives Erhitzen des Reaktanten. Dieses Argument bildet die Grundlage dieser Korrespondenz. [ABSTRACT FROM AUTHOR]

Sie sind echt: Mikrowelleneffekte in der organischen Synthese bleiben umstritten, dennoch kann es keinen Zweifel mehr an ihrer Existenz geben. Im Fokus dieser Korrespondenz steht die Frage, ob Synthesechemiker versuchen sollten, Mikrowelleneffekte strategisch zu nutzen. [ABSTRACT FROM AUTHOR]

Copyright of Chemie Ingenieur Technik (CIT) is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Es ist keine Magie! Die Effekte, die bei Mikrowellen ‐ bestrahlten chemischen Umwandlungen erzielt werden können, lassen sich in den meisten Fällen durch rein thermische Phänomene, die mit dem schnellen Aufheizen auf hohe Reaktionstemperaturen zusammenhängen, vernünftig erklären. Wie in diesem Essay erläutert, ist die Existenz der so genannten nichtthermischen oder spezifischen Mikrowelleneffekte höchst zweifelhaft. [ABSTRACT FROM AUTHOR]

Copyright of Angewandte Chemie is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Der erste Teil ist weiter nach funktionellen Oxidantien untergliedert und enthält Kapitel über photokatalytische Oxidationen mit molekularem Wasserstoff und Wasser als "grünes" Oxidationsmittel, aber auch über den Einsatz hypervalenter Iodverbindungen, die nicht unbedingt umweltschonend sind, sicher aber zu den vielseitigsten Oxidationsreagentien zählen. Ein eigenes Kapitel für die Wacker-Reaktion, das angesichts ihrer Bedeutung gerechtfertigt ist, sowie ausführliche Diskussionen goldkatalysierter oxidativer Alkin-Funktionalisierungen und jüngste Entwicklungen auf dem Gebiet von (enantioselektiven) Alkohol- und Phenoloxidationen runden das Buch ab. Das gut geschriebene Kapitel über dirigierende Sulfinyl- und Sulfonylgruppen, das in dem ansonsten gut zusammengestellten Buch doch enthalten ist, ist daher leider fehl am Platze. [Extracted from the article]

Abschnitt 6 diskutiert (Transfer)Hydrierungen zur katalytischen Desoxygenierung von Phenolen, Alkoholen und Diolen, und in Abschnitt 7 wird die Hydrogenolyse von Aryl- und gesättigten Ethern sowie von Furanen behandelt. Abschnitt 10 dreht sich um die heterogenkatalysierte Hydrierungen von O-O-Bindungen in Peroxoderivaten, in Abschnitt 11 werden Sulfoxide, Sulfone und Disulfide reduziert, und Abschnitt 12 stellt Hydrodehalogenierungen vor, die im Zuge von metallkatalysierten oder lichtinduzierten (Transfer)Hydrierungen ausgelöst werden. Die Reduktion von Nitroverbindungen und I N i -Oxiden folgt in Abschnitt 7, Abschnitt 8 beschreibt die katalytische (Transfer)Hydrierung von Aziden, und Abschnitt 9 schließt mit der katalytischen Reduktion von Nitrilen zu Alkylaminen oder Ammoniumsalzen, meist durch Hydrierung. [Extracted from the article]

Wiley‐VCH, Weinheim, 2014. 528 S., geb., 162.00 €.—ISBN 978‐3527335183 [ABSTRACT FROM AUTHOR]

Wiley ‐ VCH, Weinheim, 2014. 528 S., geb., 162.00 €.—ISBN 978 ‐ 3527335183 [ABSTRACT FROM AUTHOR]