Photolysis of azocyclohexane alone and in an oxygen atmosphere

Abstract

The photolysis of azocyclohexane involves excited molecules which can be deactivated by collision or decompose into cyclohexyl radicals and nitrogen. Arrhenius parameters for reaction (11) have been estimated, cyclo-C₆H₁₁·+(cyclo-C₆H₁₁)N₂ [graphic omitted] cyclo-C₆ H₁₂+ cyclo-C₆H₁₁N₂-cyclo-C₆H₁₀˙k₁₁= 10^5.6±0.1 exp(–6600 ± 1000 cal mol^–1/RT) dm³ mol^–1 s^–1 and a disproportionation/combination rate constant ratio of 0.99 ± 0.10 for cyclohexyl radicals has been determined.

The photolysis of azocyclohexane in an oxygen atmosphere and in the presence of cyclohexane yields cyclohexyl hydroperoxide and cyclohexanone as principal products. The results show that these are formed through a radical/radical reaction and no chain process is involved. Evidence is presented to show that the minor products, cyclohexene and water, are formed via a cyclohexyl-trioxyl radical cyclo-C₆H₁₁O₃˙.