Proton magnetic resonance studies of compounds with bridgehead nitrogen atoms. Part XXV. The stereochemistry and H nuclear magnetic resonance spectra of some perhydro-oxazolo[3,4-c]oxazines and perhydro[1,3]oxazino[3,4-c][1,3]oxazines

Abstract

The configurations and preferred conformations of a number of perhydro-oxazolo[3,4-c]oxazines and perhydro[1,3]oxazino[3,4-c][1,3]oxazines have been assigned on the basis of their n.m.r. spectra. The conformational preferences of these compounds have been interpreted in terms of the minimisation of dipolar type interactions arising from the 1,3 arrangements of the heteroatoms.