Reaction of Oxygen Atoms with Ethylene

Abstract

Reaction of O‐atoms, produced by mercury photosensitized decomposition of nitrous oxide, with ethylene has been studied at room temperature and 123°C. The primary step of the process appears to be a direct addition of the atom to the double bond to form an energy‐rich intermediate which undergoes further reactions. The following products are formed: aldehydes (CH₃CHO, C₂H₅CHO, and C₃H₇CHO), CO, CH₄, C₂H₆, C₃H₈, C₄H₁₀, H₂, very small amounts of some other substances and traces of HCHO. At 24°C O‐atoms react with ethylene 22±5 times as readily as with n‐butane. Assuming comparable pre‐exponential factors for the two processes ΔE= — 1.9 kcal/mole, so that the activation energy of addition of oxygen atoms to the double bond in ethylene is estimated at close to 3 kcal/mole. In the presence of molecular oxygen the character of the reaction is profoundly changed.