anodic oxidation proceeds either via phosphiniumradicalcations, which then attack the arenes electrophilically, or via arene radicalcations, which add the trialkylphosphite as nucleophile. Aryl phosphonates are also obtained in good yield by chemical oxidation with peroxodisulfate/AgNO3 in acetonitrile/water or glacial acetic acid. The diethylphosphinium radicalcation, formed from diethylphosphite by
Oxidative Phosphonylation of Aromatics with Ammonium Cerium(IV) Nitrate Arylphosphonates 5 and 6 can be prepared in good yields in a one-step synthesis starting from arenes with tri- or diethylphosphites and cerium ammonium nitrate (CAN) as oxidant. The selectivity of the oxidative phosphonylation is relatively low; the reactive species is a phosphite radical cation.