A promotion effect of alkaline-earth chloride on N-hydroxyphthalimide-catalyzed aerobic oxidation of hydrocarbons

Alkaline-earth chloride was used as an effective promoter for the aerobic oxidation of hydrocarbons catalyzed by N-hydroxyphthalimide (NHPI). Various hydrocarbons including benzylic compounds, cycloalkene, and cycloalkane can be easily oxygenated with molecular oxygen catalyzed by the alkaline-earth chloride/NHPI system. Ultraviolet–visible (UV–vis) spectroscopy and Fourier transform infrared (FT-IR) spectroscopy were employed to investigate the essential of the promotion effect of alkaline-earth chloride. The results revealed that alkaline-earth chloride facilitated the generation of the active species phthalimide-N-oxyl (PINO) radical which further catalyzed the oxidation of hydrocarbons.