Bridging and Terminal Arrangement of Alkylperoxo Groups in Organoindium Peroxides

Treatment of bis(tert-butyl)-2,2,6,6-tetramethyl-3,5-heptanedionatoindium, [(Me(3)C)(2)]In{Me(3)C-C(O)C(H)C(O)-CMe(3))] (1), with oxygen afforded the dinuclear alkylindium peroxide [(Me(3)C-O-O)(Me(3)}C)ln(p-OCMe3)(2)]n[Me(3)C-C(O)C(H)C(O)CMe(3))(2)] (3) in moderate yield. Compound 3 has an oxidizing peroxo group in close proximity to an ln-C bond and decomposes slowly at room temperature by quenching of these conflicting functionalities. The reaction of oxygen with the corresponding dibenzoyhnethane derivative, [(Me(3)C)(2)]InH(5)C(6)-C(O)C(H)C(O)-C(6)H(5)}] (2), gave by ligand exchange the diperoxide In(2)(mu-O-O-CMe(3))(2)(H(5)C(6)-C(O)C(H)C(O)-C(6)H(5))(4)] (4) in which the indium atoms are terminally coordinated by chelating ligands and bridged by two peroxo groups. Diperoxide 4 does not contain ln-C bonds, is thermally quite stable, and can be handled at room temperature in THF solution over several hours without decomposition. ((C) Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)