Collect. Czech. Chem. Commun. 1983, 48, 2604-2608

Oxidation of ethylenediphosphinetetraacetate anions

Jana Podlahov√° and Jaroslav Podlaha

Department of Inorganic Chemistry, Charles University, 128 40 Prague 2


The oxidation of the ethylenediphosphinetetraacetate anion and its protonated forms by iodine, periodate, hydrogen peroxide, and oxygen has been studied in aqueous solution. The oxidation by the first three reagents is fast and yields a single product, bis(phosphine oxide), which has been isolated and characterized as ethylenebis(phosphinyl)tetraacetic acid. The oxidation by molecular oxygen proceeds considerably more slowly; in weakly acid solutions its rate is determined by the properties of the oxygen rather than by the electronic structure of the various protonated substrate species. The inhibiting effect of the phosphonium structures takes place only in strongly acid solutions.