Zobrazeno 1 - 10
of 30
pro vyhledávání: '"Hans Fritz"'
Autor:
Hans Fritz
Publikováno v:
Bulletin des Sociétés Chimiques Belges. 93:559-569
Publikováno v:
Helvetica Chimica Acta. 75:1052-1060
Catalytic double osmylation is described for a series of cyclohexadienes in acetone/H2O in the presence of the co-oxidant N-methylmorpholine N-oxide (NMO). The formation of polyols occurred stereospecifically with cyclohexadienes 3,7, and 11a, leadin
Publikováno v:
Chemische Berichte. 124:1777-1794
3-Aza- and syn-3,7-Diazaoctabisvalene. - Syntheses, X-ray Structural Analyses, Novel Heterocycles Preparatively useful routes for 3-aza- and syn-3,7-diazaoctabisvalenes have been designed based on well available materials. Thus, 7-cyano-3-azaoctabisv
Publikováno v:
Magnetic Resonance in Chemistry. 28:331-336
Trifluoroacethydrazide is unstable even in the solid state with respect to hydrazonium N,N′-ditrifluoroacetyl hydrazinate, as shown by 15N and 13C NMR spectroscopy. The 1H, 13C and 15N NMR data and rotamer distributions of formyl-, acet- and triflu
Publikováno v:
Tetrahedron. 43:3747-3763
Zusammenfassung In a new concept for the synthesis of 20'-deethyl-20'-deoxyvin-blastine, Nb-seco-cleavamine derivatives 1a , 2a are possible precursors. For the synthesis of these compounds the indolizino(5,4-b]indoles 8I , II were treated with benzy
Publikováno v:
Helvetica Chimica Acta. 71:404-418
Intramolecular Cycloaddition Reactions with Azomethine Ylides: Synthesis and NMR Investigations of Some Macrolide-Type Paracyclophanes Several aziridine derivatives bearing a para-substituted phenyl group have been prepared as precursors of azomethin
Autor:
Vunnam Ranga Rao, Dieter Müller, Kuppuswamy Nagarajan, S. J. Shenoy, R. K. Shah, Wilhelm J. Richter, Hans Fritz
Publikováno v:
Helvetica Chimica Acta. 71:77-92
Homophthalic acid (1) undergoes reaction with 1,2-, 1,3-, and 1,4-diamines to give condensed 1(2H)-isoquinolinones like 2, 4, 13, and 25, which exhibit marked enamine character. These are attacked by electrophiles at the N or C terminus. Some notable
Publikováno v:
Tetrahedron Letters. 27:3135-3138
Reaction of [E,E]-hexa-2,4-dienal 2 with nitrosobenzene led regiospecifically to the Diels-Alder cycloadduct 4b which is unstable at room temperature. Its enol form 5b underwent a hetero-Cope rearrangement, giving ultimately the pyrroloindole 7b . Si
Publikováno v:
Tetrahedron Letters. 27:4003-4006
On thermal treatment of the aziridines 5a - f intramolecular cycloaddition reactions of the intermediate azomethine ylides 6 result in the formation of the metacyclophanes 7 - 9 . For 7a and 7b the conformational barriers areestimated to be approxima
Autor:
Hans Fritz, Christoph Rücker
Publikováno v:
Rücker, C & Fritz, H 1988, ' Unusual two-bond 13 C, 13 C coupling constants in sulphones ', Magnetic Resonance in Chemistry, vol. 26, no. 12, pp. 1103-1108 . https://doi.org/10.1002/mrc.1260261213
A measurable coupling between carbon atoms through the SO 2 group is observed in a series of structurally diverse sulphones. In open‐chain (single coupling path) sulphones this 2J coupling ranges from 5.5 to 27.2 Hz, while in cyclic (multiple coupl