Nitrones. Part VII. The photochemistry and cycloaddition of a monocyclic α-dinitrone

Abstract

The photochemical isomerisation of the α-dinitrone, hexamethyl-2,3-dihydropyrazine 1,4-dioxide into a nitrone-oxaziridine 2,2,3,3,5,6-hexamethyl-1,4-diaza-7-oxabicyclo[4,1,0]hept-4-ene 4-oxide and a mixture of dioxaziridines is described. Cycloaddition of the nitrone-oxaziridine with acrylonitrile, and the structure of the adducts, are discussed. The i.r. spectra are used in the structural assignments. This cycloaddition indicates that the inactivity of the original monocyclic α-dinitrone to cycloadditions is not due to the pyrazine ring but more likely to the conjugation of the nitrone functions.