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of 146
pro vyhledávání: '"Wolfgang R. Roth"'
Autor:
Wolfgang R. Roth
Publikováno v:
Filologia e Linguística Portuguesa, Vol 2, Pp 61-79 (2017)
Filologia e Linguística Portuguesa, Vol 2, Pp 61-79 (1998)
Filologia e Linguística Portuguesa, Vol 2, Pp 61-79 (1998)
A definition of the field of semantics is attempted, approaching its development from the earliest studies, in connection with those of etymology as well as with those of classical grammar. Reasons are given for the prevalence of the lexical approach
Autor:
Volker Paschmann, Wolfgang R. Roth
Publikováno v:
Liebigs Annalen. 1996:1329-1336
On the Energy Well of Diradicals, VIII1 . – Energy Profile of the Degenerate Methylenecyclobutane Rearrangement From the temperature and oxygen dependence of the trapping rates of the diradicals 4 and 6, recombination enthalpies of 4.7 and 1.8 kcal
Publikováno v:
Liebigs Annalen. 1996:409-430
Forbidden Reactions, II. – The Disrotatory Cyclobutene Ringopening The energy profiles for the con- and disrotatory opening of benzocyclobutene, methylenecyclobutene, and cyclobutene derivatives were established by NO and oxygen trapping. The entha
Publikováno v:
Liebigs Annalen. 1996:1323-1328
On the Energy Well of Diradicals, VI1 . – The Energy Profile for the NO2-Addition to Conjugated Double Bonds: A Reaction with Negative Activation Energy From the NO and temperature dependence of the reaction rates of 1,3-butadiene, styrene, and met
Trimethylenemethane Derivatives Stabilized by Conjugation II − Concerted or Nonconcerted Generation?
Publikováno v:
European Journal of Organic Chemistry. 2001:4081-4099
The concerted formation of the orthogonal trimethylene-type diradicals 3, 6, and 12 has been demonstrated for the three homofulvenes 2, 4, and 7 and shown to proceed preferentially in a disrotatory manner. The same type of orthogonal diradicals are f
Autor:
Hans-Jürgen Figge, Wolfgang R. Roth
Publikováno v:
European Journal of Organic Chemistry. 2000:1983-1986
Publikováno v:
European Journal of Organic Chemistry. 1999:813-822
Whereas 1,5-dimethylsemibullvalene (1b) equilibrates with 1,5-dimethylcyclooctatetraene (2b), the semibullvalene-2,6-dicarbonitriles 13 rearrange irreversibly to afford mixtures of the isomeric cyclooctatetraene-1,5-dicarbonitriles 14 and 15. Arrheni
Autor:
Rolf Gleiter, Gerd Fritzsche, U. E. Hackler, Holger Lange, Wolfgang R. Roth, Volker Paschmann
Publikováno v:
European Journal of Organic Chemistry. 1998:961-967
Autor:
Michael Quast, Wolfgang R. Roth
Publikováno v:
European Journal of Organic Chemistry. 1998:763-768
Activation parameters have been determined in the gas phase for the geometrical isomerization of the double bonds in two phenyl-substituted methylenecyclopropanes (2 and 8). Comparison with the analogous values for three sterically non-restricted sty
Publikováno v:
Angewandte Chemie. 101:1092-1094