NMR/NOE elucidation of the stereostructure of cycloadducts of acetonitrile oxide with norbornane/ene-fused dihydro-oxazines
作者:Pál Sohár、Géza Stájer、Angela E. Szabó、Gábor Bernáth
DOI:10.1002/mrc.1260290713
日期:1991.7
Norbornane‐di‐endo‐ and ‐di‐exo‐fused dihydro‐1,3‐oxazines underwent cycloaddition with in situ prepared acetonitrile oxide to yield tetracyclic 1,2,4‐oxadiazolines. Either the CC bond of the double dipolarophiles with the norborneneskeleton was saturated to give isoxazoline regioisomers, or a second molecule of the dipole added to the CN bond, resulting in the formation of a bis‐adduct. The structures
Configuration and NMR study of tricyclic oxazines fused to a norbornene or norbornane skeleton
作者:P. Sohár、G. Stájer、G. Bernáth
DOI:10.1002/omr.1270210812
日期:1983.8
AbstractTricyclic oxazines fused with norbornane or norbornane were synthesized for pharmacological and stereochemical purposes. Analogous oxazin‐2‐ones and ‐2‐thiones were also obtained. The diendo or diexo anellation of the hetero ring to the norbornene or norbornane skeleton was confirmed by 1H and 13C spectral data. The assignment of the proton signals was proved and the proton‐proton coupling values were determined by double resonance experiments. With mono‐ and dichloroacetyl chloride, the oxazines fused to norbornene gave azetidinones which are mixtures of two isomers. The mixtures were separated into homogeneous substances, the configuration and conformation of which were determined via differential NOE experiments.