THE PHOTOOXYGENATION OF MAGNESIUM‐OCTAETHYLPORPHIN*

Abstract

Abstract— Octaethylporphinato‐magnesium (MgOEP) has been photooxygenated in quantitative yield to a brown compound with its main absorption peaks at 825 and 408 nm. The product has been isolated and evidence suggests that it is 4‐formyl‐5‐oxa‐octaethylporphinato‐magnesium II. II is very labile to hydrolysis, the main isolated decomposition product being 1, γ‐dioxo‐8‘‐formyl‐octaethyl violin III. The absorption, i.r., PMR and mass spectra of II and III are reported and possible paths to their formation are discussed.