A molybdenum complex bearing a tetraphosphine ligand as a precursor for heterobimetallic complexes.

The reactions of [CpMoH(κ(3)-P4)] (2; P4 = meso-o-C6H4(PPhCH2CH2PPh2)2) with protic acids gave [CpMo(κ(4)-P4)](+) (4(+)) via the intermediary formation of [CpMoH2(κ(3)-P4)](+). Treatment of 2 with iodine provided the cationic complex [CpMoHI(κ(3)-P4)][I] (5[I]). Early-late heterobimetallic complexes of the type [CpMoH(μ-P4-1κ(3):2κ)MLnCl] (MLn = Ru(Hmb)Cl (6), Ir(η(5)-C5Me5)Cl (7), Rh(cod), Ir(cod), Pd(η(3)-C3H5) (10); Hmb = η(6)-C6Me6, cod = η(4)-1,5-cyclooctadiene) were synthesised by reacting 2 with [MLn(μ-Cl)]2, and their structures were characterised by NMR spectroscopy. The hydride ligand in 6 was replaced by chloride in chlorinated organic solvents to give [CpMoCl(μ-P4-1κ(3):2κ)Ru(Hmb)Cl2] (11). Self-reaction of 10 produced allylbenzene and [CpMo(μ-H){μ-PhP(CH2)2P(Ph)-o-C6H4-P(Ph)(CH2)2PPh2-1κ(3):2κ(2)}PdCl] (12), in which the Mo-Pd edge was bridged by a hydride ligand and the phosphide moiety emerged from the loss of one phenyl group. The molecular structures of 4[Cl], 4[OTf], 5[I], 6, 7, 11, and 12 were established by single-crystal X-ray analysis.