On triazoles XVI. The reaction of 5-amino-1,2,4-triazoles with β- and γ-oxo esters. A novel N-carbonylation reaction

5-Amino-1,2,4-triazoles reacted with alifatic β-oxo-esters to yield besides the unexpected 1,2,4-triazolo-[1,5-a]-1,3,5-benzotriazepin-5-one derivative 7 either the corresponding esters 5 and 6 or a 1:2 condensation product 8. To the contrary alicyclic and heterocyclic β-oxo-esters formed in the above reaction only derivatives 7. The proposed mechanism of the formation of 7 involving a novel N-carbonylation reaction was proved by the isolation of the by-products and the intermediate of the reaction. Repeating the above reaction with a γ-oxo-ester, namely the ethyl levulinate, derivatives 17 and 18 , respectively, representing two new ring systems were obtained.     

Collision processes of Hydride species in Hydrogen plasmas: III. The Silane family

Cross sections are provided for most important collision processes of the Silicon‐Hydrides from the “Silanefamily”: SiH_y (y = 1 ? 4) molecules and their ions SiH⁺_y, with (plasma) electrons and protons. The processes include: electron impact ionization and dissociation of SiH_y, dissociative excitation, ionization and recombination of SiH⁺_y ions with electrons, and charge ‐ and atom ‐ exchange in proton collisions with SiH_y. All important channels of dissociative processes are considered. Information is also provided on the energetics (reactants/products energy loss / gain) of each individual reaction channel. Total and partial cross sections are presented in compact analytic forms. The critical assessment of data, derivation of new data and presentation of results follow closely the concepts of the recently published related databases for Carbon‐Hydrides, namely for the Methane family [1, 2], and for the Ethane‐ and the Propane families [3], respectively. (© 2003 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

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Are changes in morphology clear indicators for the glass transition in thin polymer films? Tentative ideas

I present some tentative ideas on the possibility of plastic deformation which might be relevant in ultra-thin polymer films at temperatures close but below the glass transition temperature. Several possible sources for sufficiently strong forces are discussed. The relevance of such forces in experiments aiming at determining thin-film properties like the glass transition temperature, thermal expansion or surface morphology is discussed. Received 19 September 2001 and Received in final form 5 December 2001     

Zwei Anwendungen der Bruhatschen Funktion

Ohne ZusammenfassungHerrnG. Köthe zum 60. Geburtstag am 25. 12. 1965 gewidmet     

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