PHOTOCHEMICAL DECOMPOSITION AND ISOMERIZATION OF ALIPHATIC AZO COMPOUNDS

Abstract — Incorporation of the azo group into the bicyclo{2.2.2]octane skeleton leads to "reluctant " azoalkanes which undergo photochemical loss of nitrogen with low quantum efficiency. The barrier to singlet decom-position which these compounds possess can be surmounted by raising the temperature or can be lowered by making the azoalkane more labile ther-mally. The only products detected thus far from bridgehead vinyl substi-tuted 2,3—diazabicyclo[2.2.2}oct—2—enes are those of ring opening. Some of the properties of cis l—azobicyclo{2.2.l]heptane, an extraordinarily stable acyclic cis azoalkane, are described