摘要:

AbstractThis article describes the formation of carbon‐metal bonds by reacting carbonylmetalate ions with fluorocarbons. Complex formation depends on the nucleophilic behavior of the anions, and the susceptibility of fluorocarbons to this form of attac

ISSN:0570-0833    

DOI:10.1002/anie.196807471

出版商:Hüthig&Wepf Verlag    

年代:1968

数据来源: WILEY

摘要:

AbstractOlefins are normally preferentially attacked by electrophiles. This trend is strengthened in enol ethers and enamines, and is particularly pronounced in tetramethoxyethylene and in tetraaminoethylenes. These electron‐rich olefins are accordingly also excellent reducing agents. In their reactivity, therefore, they behave as counterparts of tetracyanoethylene. This compound shares with the electron‐rich olefins a strong tendency to undergo cycloadditions, the electron‐rich olefins adding particularly readily to electrop

ISSN:0570-0833    

DOI:10.1002/anie.196807541

出版商:Hüthig&Wepf Verlag    

年代:1968

数据来源: WILEY

摘要:

AbstractDepending on the nature of the electron acceptor and of the tetraaminoethylene (TAE), the electron pairs of the ethylenic double bond (A), of the nitrogen (B), or of the entire electronic system (C) of TAE react with the acceptor. Thus oxidizing agents convert TAE into the mono‐and dications TAE+and TAE2+by path (A); acids add on to the ethylenic carbon (A) or the amine nitrogen (B) (the addition of acid is often followed by cleavage of the CC or CN bond); organic π‐electron acceptors from deeply colored donor‐acceptor complexes wi

ISSN:0570-0833    

DOI:10.1002/anie.196807661

出版商:Hüthig&Wepf Verlag    

年代:1968

数据来源: WILEY

摘要:

AbstractThe stereochemical configuration at the initial site of heterolysis in a carbonium ion process in solution controls the specificity of migration two steps later in many sequential multiple rearrangements. These “memory effects” are attributable to the presence on the potential energy surface of small, hitherto undetectable minima. A variety of structural, stereochemical, and isotopic marking techniques are used to demonstrate that memory effects are a general feature of the ring‐expansion route to bicyclic carbonium ions. The intermediates formed in these reactions, although necessarily symmetrical or quasi‐symmetrical at equilibrium, act unsymmetrically. The memory effect uses the rate of an intramolecular carbonium ion rearrangement as a calibration with which to compare the rate of symmetrization. In this way, the system functions as a sensor of sub

ISSN:0570-0833    

DOI:10.1002/anie.196807791

出版商:Hüthig&Wepf Verlag    

年代:1968

数据来源: WILEY

摘要:

AbstractThe dehydration of alcohols on γ‐aluminum oxide, which yields water, olefins, and/or ethers, was studied with the aid of kinetic methods and IR spectroscopy. The unimolecular olefin formation probably proceeds via a surface compound, in which an alcohol molecule is joined by two angular H‐bonds to an OH group and an oxygen ion on the surface. The ether formation (bimolecular reaction), on the other hand, requires OH groups and oxygen and aluminum ions on the surface. The ether is formed from a surface alkoxide group and molecularly adsorbed alc

ISSN:0570-0833    

DOI:10.1002/anie.196807911

出版商:Hüthig&Wepf Verlag    

年代:1968

数据来源: WILEY

ISSN:0570-0833    

DOI:10.1002/anie.196808051

出版商:Hüthig&Wepf Verlag    

年代:1968

数据来源: WILEY

ISSN:0570-0833    

DOI:10.1002/anie.196808062

出版商:Hüthig&Wepf Verlag    

年代:1968

数据来源: WILEY

ISSN:0570-0833    

DOI:10.1002/anie.196808081

出版商:Hüthig&Wepf Verlag    

年代:1968

数据来源: WILEY

ISSN:0570-0833    

DOI:10.1002/anie.196808092

出版商:Hüthig&Wepf Verlag    

年代:1968

数据来源: WILEY

ISSN:0570-0833    

DOI:10.1002/anie.196808112

出版商:Hüthig&Wepf Verlag    

年代:1968

数据来源: WILEY