Search for Singlet Oxygen in the Decomposition of Hydrogen Peroxide by Mineral Compounds in Aqueous Solutions

Article abstract of DOI:10.1021/ja00307a002

The possibility of singlet oxygen (¹O2) occurrence in the decomposition of H2O2 by mineral compounds in aqueous basic solutions was examined.Tetrapotassium rubrene-2,3,8,9-tetrcarboxylate was used as a trap, giving an endoperoxide detected by HPLC.We found that four families of mineral compounds lead to the formation of the endoperoxide: the oxides of the alkaline earths Ca, Sr, and Ba; the derivatives of elements of groups 3A, 4A, 5A, and 6A in d⁰ configuration (expect niobium); the oxides of actinides and lanthanides; and finally the oxidizers ClO^-, BrO^-, Au³⁺, IO3^-, and IO4^-.One compound in each family was selected for further investigation in order to strengthen the ¹O2 hypothesis.Thus, the yield of the endoperoxide of potassium 9,10-diphenylanthracene-2,3,6,7-tetracarboxylate was enhanced when the parent compound was introduced in a mixture of H2O2 + (ClO^-, Nd2O3, MoO4^2-, Ca(OH)2 + deuterated water instead of light water.