An Unusual Conversion of Paramagnetic [3-Cl-3,3,8-{Ph2P(CH2)nPPh-µ-(C6H4-ortho)}-1,2-(CH3)2-closo-3,1,2-RuIIIC2B9H8] (n = 3 and 4) to Form the First 18-Electron P-Phenylene ortho-Cycloboronated closo-Ruthenacarboranes with a Dioxygen Ligand

Abstract

Treatment of [3-Cl-3,3,8-[Ph2P(CH2)nPPh-µ-(C6H4-ortho)]-1,2-Me2-closo-3,1,2-RuIIIC2B9H8] (1, n = 3; 2, n = 4) with an excess of KOH in a 1:1 benzene/methanol mixture at room temperature in air affords new dioxygen closo-ruthenacarborane complexes [3-(η2-O2)-3,3,8-[Ph2P(CH2)nPPh-µ-(C6H4-ortho)]-1,2-Me2-closo-3,1,2-RuIIIC2B9H8] (3, n = 3) and (4, n = 4) in 42.5% and 45.8% yield respectively. The structures of dioxygen complexes 3 and 4 were established by single-crystal X-ray diffraction. The IR and multinuclear NMR data [1H, 13C{1H}, 31P{1H} and 11B{1H}] along with 2D HSQC correlation spectra for the new dioxygen closo-ruthenacarboranes are discussed.

Keywords

• ruthenacarboranes
• oxygen-type ligands
• NMR-spectra
• X-ray diffraction