摘要:

AbstractA general structural principle for organic compounds that have the capacity for two‐stage electron transfer is based on the following reaction sequence:In this scheme one or both of the entities X may be replaced by Y⊖. The radical partners in these systems often have very high thermodynamic stability. The choice of the end groups X and Y, (partial) inclusion of n‐systems in rings, alteration of the number of vinylene groups, and aza‐substitution make many variations possible. By means of this general structural principle numerous known compounds are brought together and new redox systems are simultaneously set up. The aim of the present review is to demonstrate the broad applicability of this principle, to indicate its significance for science and industry, and to describe some re

ISSN:0570-0833    

DOI:10.1002/anie.197808753

出版商:Hüthig&Wepf Verlag    

年代:1978

数据来源: WILEY

摘要:

AbstractElectrons produced in a gaseous, liquid, or solid solvent are called dissolved electrons or excess electrons. These excess electrons can exist as quasi‐free particles of high mobility in a delocalized state, comparable with electrons in a metal; or as bound particles of low mobility they can be localized within narrow limits—in a solvent cavity formed by repulsive forces. Localized electrons can also be solvated like normal ions. Characteristically, such solvated electrons exhibit broad and extensive absorption spectra in the visible to near infrared spectral range. The localized and delocalized states of the excess electrons can be in equilibrium with each other, such that a continuous transition of the properties between the limiting extremes can be observed. The reactions of the excess electrons with suitable acceptors (substrates) are initiated by an attachment‐detachment equilibrium A + e−⇌ A−which is followed by further chemical rearrangements. The rate constants of these reactions vary by more than 15 powers of ten depending on the substrates and the solvents. Most of the properties of excess electrons in solution can be interpreted by means of a model which is easily understandable but quantitatively evaluated only with consider

ISSN:0570-0833    

DOI:10.1002/anie.197808871

出版商:Hüthig&Wepf Verlag    

年代:1978

数据来源: WILEY

摘要:

AbstractA new, fast, and simple method based on size exclusion chromatography permits determination of the volumes of open and closed pores of rigid solids such as silica or porous glasses, together with the specific surface and the pore‐size distribution for pore diameters ranging from 10 to 4000Å. The results are in good agreement with those obtained by classical methods (capillary condensation, mercury porosimetr

ISSN:0570-0833    

DOI:10.1002/anie.197809011

出版商:Hüthig&Wepf Verlag    

年代:1978

数据来源: WILEY

摘要:

AbstractOwing to the ready availability of the starting materials, the functionalization of saturated hydrocarbons for preparing chemical intermediates and products represents an attractive goal. The possibility of converting alkane in a controlled way into alcohols, ketonesetc., i.e.to oxyfunctionalize them, is particularly challenging. After a short account of previous methods used for the oxidation of alkanes, particular emphasis will be given to recently developed reactions of alkanes with oxygenating agents in superacidic media.

ISSN:0570-0833    

DOI:10.1002/anie.197809091

出版商:Hüthig&Wepf Verlag    

年代:1978

数据来源: WILEY

ISSN:0570-0833    

DOI:10.1002/anie.197809321

出版商:Hüthig&Wepf Verlag    

年代:1978

数据来源: WILEY

ISSN:0570-0833    

DOI:10.1002/anie.197809331

出版商:Hüthig&Wepf Verlag    

年代:1978

数据来源: WILEY

ISSN:0570-0833    

DOI:10.1002/anie.197809341

出版商:Hüthig&Wepf Verlag    

年代:1978

数据来源: WILEY

ISSN:0570-0833    

DOI:10.1002/anie.197809351

出版商:Hüthig&Wepf Verlag    

年代:1978

数据来源: WILEY

ISSN:0570-0833    

DOI:10.1002/anie.197809361

出版商:Hüthig&Wepf Verlag    

年代:1978

数据来源: WILEY

ISSN:0570-0833    

DOI:10.1002/anie.197809371

出版商:Hüthig&Wepf Verlag    

年代:1978

数据来源: WILEY