NEW DIMERIC PRODUCTS FROM THE THERMAL AND PHOTOCHEMICAL DECOMPOSITIONOF 2-AZIDOPHENAZINE

Re-examination of the thermal and photochemical decomposition of 2-azi dophenazine reveals new pathways. Thus, besides reduction to the amine , the triplet nitrene yields the azo derivative and phenazino[1',2':5, 6]pyridazino[4,3-a]phenazine while the singlet nitrene rearranges to t he dehydroazepine and adds a further molecule of azide to yield an ope n-chain imine. The factors leading to the predominance of ''dimeric'' products from this type of heterocyclic azides are discussed.