Réactivité du nucléophile azoture vis à vis de cations hétérocycliques aromatiques. VI. Cas des triaryl-2,4,6 oxaziniums-1,3

Nucleophilic attack of sodium azide on 2,4,6-triaryl-1,3-oxazinium species gives high yields of β-tetrazolo-trans-benzalacetophenones from the corresponding 2-azido-1,3-oxazines. The rearrangement of the azido oxazines likely proceeds via tautomerism of the intermediate iminoazides. If the formation of the 2-azido-1,3-oxazines is under kinetic control, these results are a rare example of high regioselectivity in nucleophilic attack at the C2 carbon of 1,3-oxazinium species.The reaction behaviour of the 1,3-oxazinium/N₃⁻ system is discussed, together with results obtained from the 2,4,6-triphenylpyrilium/N₃⁻.