Formation of μ-peroxo-platinum complexes via attack of metallic and related electrophiles at η 2-dioxygen-platinum complexes

Abstract

Reactions of PtO 2(PPh 3) 2 with metallic chlorides or related chlorides L n MCl in CD 2Cl 2 at −40 °C gave good yields of the corresponding μ-peroxo complexes Pt(OOML n )(Cl)(PPh 3) 2 ( 2) (L n M  Me 3Si, Ph 3Si, Ph 3Ge, Ph 2P(O), (PhO) 2P(O), PhS(O) 2) which were confirmed by 31P NMR measurements. In 31p NMR data of 2, the J(Pt-P) values for PPh 3 trans to OOML n increased as the electron-withdrawing ability of L n M increased, whereas the J(Pt-P) values for PPh 3 cis to OOML n showed somewhat unusual inverse linear dependency on this ability. Treatment of PtO 2(PR 3) 2 with [Pt 2(μ-OH) 2(PR′ 3) 4] 2+ afforded μ-peroxo-diplatinum complexes [(PR 3) 2Pt(μ-OO)(μ-OH)Pt(PR′ 3) 2] + (R  R′  Ph, p-tolyl; PR 3  PPh 3; PR′ 3PMe 2Ph, 1 2 Ph 2PCH 2CH 2PPh 2). Complexes 2 containing electron-withdrawing peroxo ligands (L n MPh 2P(O), (PhO) 2P(O), PhS(O) 2) oxidized norbornene and cyclohexene to the corresponding epoxides.