STEREOCHEMICAL STUDIES-75 SATURATED HETEROCYCLES-62. CONNECTION BETWEEN THE DIASTEREOSELECTIVITY AND THE DOMINANT CONFORMATION IN THE FORMATION OF CONDENSED-SKELETON 1,3-OXAZINES, FIRST X-RAY DIFFRACTION EVIDENCE OF N-OUTSIDE CONFORMATION

Article abstract of DOI:10.1016/S0040-4020(01)91511-X

The rapid, spontaneous epimerization occuring at the C(2) chirality centre of a new diastereomeric (r-4,c-2,c-5)-2-(p-nitrophenyl)-3-methyl-4,5-tetramethylenetetrahydro-1,3-oxazine led to the conclusion that the configuration at C(2) of the bicyclic 1,3-o