1,2-Dinitrosobenzene in argon matrices at 14 K

Photolysis of benzofurazan 1-oxide 3 and 2-nitrophenyl azide 7 in Ar matrices at 14 K yielded 1,2-dinitrosobenzene 4, which had not previously been characterized; the IR and UV absorptions of matrix-isolated 4 have been recorded, and its, thermal and photochemical reversion to 3 has also been observed, 15N labelling experiments lend strong support to the assignment.