92897-88-6Relevant academic research and scientific papers
Isoxazolinyldioxepins. Part 1. Structure-Reactivity Studies of the Hydrolysis of Oxazolinyldioxepin Derivatives
Camilleri, Patrick,Munro, David,Weaver, Karen,Williams, David J.,Rzepa, Henry S.,Slawin, Alexandra M. Z.
, p. 1265 - 1270 (2007/10/02)
The preparation and acid catalysed hydrolysis of a number of isoxazolinyldioxepins is reported.Individual diastereoisomer pairs were isolated by column chromatography and shown to differ significantly in their hydrolytic stability at acidic pH.The crystal structures of one diastereoisomer pair reveal that conformational differences induce a selective stereoelectronic effect at the acetal centre of the more hydrolytically labile isomer, while the less labile isomer shows no such selectivity.
Isoxazolinyldioxepins. Part 1. Structure-Reactivity Studies of the Hydrolysis of Oxazolinyldioxepin Derivatives
Camilleri, Patrick,Munro, David,Weaver, Karen,Williams, David J.,Rzepa, Henry S.,Slawin, Alexandra M. Z.
, p. 1929 - 1934 (2007/10/02)
The preparation and acid catalyzed hydrolysis of a number of isoxazolinyldioxepins is reported.Individual diastereoisomer pairs were isolated by column chromatography and shown to differ significantly in their hydrolytic stability at acidic pH.The crystal structures of one diastereoisomer pair reveal that conformational differences induce a selective stereoelectronic effect at the acetal centre of the more hydrolytically labile isomer, while the less labile isomer shows no such selectivity.
PHOTO-INDUCED REARRANGEMENT OF ISOXAZOLINES - A PATHWAY TO 2,4,5,8-TETRAHYDRO-1,3-DIOXA-5-AZOCINE DERIVATIVES
Fisera, Lubor,Oremus, Vladimir,Stibranyi, Ladislav,Timpe, Hans-Joachim,Matusova, Alena
, p. 1982 - 1993 (2007/10/02)
4-R-Substituted-8-X-phenyl-3,5,10-trioxa-9-azabicyclodec-8-enes (X = H, 4-CH3, 4-OCH3, 4-Cl, 4-Br, 4-F, 3-NO2, 3-Cl, 3-Br) have been prepared by cycloaddition of substituted benzenenitriloxides with 2-R-substituted 1,3-dioxep-5-enes (R = H, CH3, C6H5).A mixture of the endo and exo adducts is formed, if R is CH3 or C6H5.Their irradiation produces high yields of the title compounds as the single products.High selectivity of the photo-rearrangement is due to resonance stabilization of the biradical with p electrons of the oxygen atom.The quantum yields of the photoreaction vary from 0.02 to 0.04 depending on the substituent X.An unexpected dependence has been found between the quantum yield of the photo-rearrangement and stereochemical arrangement of the 4-R-substituent: exo derivatives exhibit higher values than the endo derivatives.Also different are UV spectra of the endo and exo derivatives.A new synthesis principle is described enabling preparation of (n+1)-membered heterocycles from n-membered heterocycles.
PHOTOINDUZIERTE UMLAGERUNG VON ISOXAZOLINEN: SYNTHESEWEG ZU 2,4,5,8-TETRAHYDRO-1,3-DICX-5-AZOCINEN
Fisera, L.,Stibranyi, L.,Matusova, A.,Cremus, V.,Timpe, H.-J.
, p. 2731 - 2734 (2007/10/02)
A high yield 2,4,5,8-tetrahydro-1,3-diox-5-azocine synthesis, which employs a sequence of cycloaddition and photoinduced rearrangement has been developed.
