摘要:

AbstractRobert B. Woodward, a supreme patterner of chaos, was one of my teachers. I dedicate this lecture to him, for it is our collaboration on orbital symmetry conservation, the electronic factors which govern the course of chemical reactions, which is recognized by half of the 1981 Nobel Prize in Chemistry. From Woodward I learned much: the significance of the experimental stimulus to theory, the craft of constructing explanations, and the importance of asethetics in science. I will try to show you how these characteristics of chemical theory may be applied to the construction of conceptual bridges between inorganic and organic chemistry.

ISSN:0570-0833    

DOI:10.1002/anie.198207113

出版商:Hüthig&Wepf Verlag    

年代:1982

数据来源: WILEY

摘要:

AbstractIn contrast to the thoroughly studied plarity properties of pure liquids, only little is known about the polarity of mixtures of liquids, although the majority of machanistic and preparative work is not carried out in pure phases. Using a widely applicable two‐parameter equation, polar behavior of binary liquid mixtues can be described quantitatively as a function of their composition. Based on this equation, satisfactory explanations are found for deviations observed for binary solvent mixtures from the linear correaltion of polarity scales, as well as for the unusual activation parameters estimated byWinsteinfor solvolysis oftert‐butyl chloride. Applications of the equation range from a rapid test for determining water contents of solvents, the study of reaction mechanisms, to polymer chemis

ISSN:0570-0833    

DOI:10.1002/anie.198207241

出版商:Hüthig&Wepf Verlag    

年代:1982

数据来源: WILEY

摘要:

AbstractIn this progress report an attempt is made to rationalize, from a mechanistic point of view, the different ways in which oxygen is transferred from inorganic and organic peroxides to nucleophilic substrates, particularly olefins. Oxygen transfer from transition‐metal peroxides, which is relevant to catalytic oxidations using O2, H2O2or ROOH, occursviaa cyclic or “pseudocyclic” peroxymetalation in which a dioxametallacycle is formed. Owing to the wide discrepancy between peroxymetalation and the conventional oxidation mechanism,i.e.nucleophilic attack of the substrate at the electrophilic “active oxygen”, we propose an alternative mechanism involving dioxiranes as the reactive species. The generation of dioxiranes appears to be a common denominator in the reactions of most organic peroxidese.g.peroxy acids, the reaction of electrophilic ketones with H2O2, or ozonizations. Oxygen transfer from dioxirane reagents probably involves the formation of a charge‐transfer π‐complex between the substrate and the carbon atom of the dioxirane, and the subsequent formation of a cyclic peroxidi

ISSN:0570-0833    

DOI:10.1002/anie.198207341

出版商:Hüthig&Wepf Verlag    

年代:1982

数据来源: WILEY

摘要:

AbstractThe prostanoids continue to attract a great deal of attention, particularly in the pharmacological sector. Many of the numerous biological studies on prostaglandins deal with their cardiovascular effects. The pronounced antihypertensive and platelet aggregation‐inhibiting properties of prostacyclin (PGI2) resulted in world‐wide efforts to synthesize acid‐stable analogues of the natural product. Whereas refined analytical procedures disproved the hypothesis that PGI2is a circulating hormone, exploratory human trials with PGI2confirmed the pharmacological findings obtained from animal experiments. Clinical studies of PGI2analogues have been started.In vitrostudies on isolated vessels revealed that potent cardiovascular drugs stimulate prostacyclin synthesis; however, it has not as yet been possible to demonstrate whether these effects are also of therapeutic significance. A survey of the PGI2analogues synthesized so far is presented, and, with the aid of a few examples, the problems encountered during their synthesis are outlined; structure‐activity relationships are also di

ISSN:0570-0833    

DOI:10.1002/anie.198207511

出版商:Hüthig&Wepf Verlag    

年代:1982

数据来源: WILEY

ISSN:0570-0833    

DOI:10.1002/anie.198207641

出版商:Hüthig&Wepf Verlag    

年代:1982

数据来源: WILEY

摘要:

AbstractThe complete manuscript of this communication appears in:Angew. Chem. Suppl. 1982, 1670. DOI:10.1002/anie.198216700

ISSN:0570-0833    

DOI:10.1002/anie.198207651

出版商:Hüthig&Wepf Verlag    

年代:1982

数据来源: WILEY

ISSN:0570-0833    

DOI:10.1002/anie.198207661

出版商:Hüthig&Wepf Verlag    

年代:1982

数据来源: WILEY

ISSN:0570-0833    

DOI:10.1002/anie.198207671

出版商:Hüthig&Wepf Verlag    

年代:1982

数据来源: WILEY

ISSN:0570-0833    

DOI:10.1002/anie.198207681

出版商:Hüthig&Wepf Verlag    

年代:1982

数据来源: WILEY

ISSN:0570-0833    

DOI:10.1002/anie.198207752

出版商:Hüthig&Wepf Verlag    

年代:1982

数据来源: WILEY