Four-legged piano stool molybdenum(II) compounds without carbonyl ligands - 3? cyclopentadienyl and indenyl complexes containing the tridentate ligand Ph2PCH2CH2P(Ph)CH2CH 2PPh2(triphos) via reduction of molybdenum(III) precursors

Article abstract of DOI:10.1016/0277-5387(95)00517-X

The carbonyl-free, half-sandwich molybdenum(II) complexes CpMoCl(triphos) (1) and IndMoX(triphos) [X = Cl (2); I (3); triphos = Ph₂PCH₂CH₂P(Ph)CH₂CH ₂PPh₂; Ind = η⁵-C₇H₉ or indenyl] have been synthesized by either reduction of CpMoCl₂ in the presence of triphos or by reduction and transmetallation of MoX₃(triphos) (X = Cl, I) with CpNa or IndNa. The spectroscopic properties indicate a saturated, 18-electron structure in each case. All compounds are susceptible to oxidation in chlorinated hydrocarbons and the oxidation of 1 has been studied in detail both chemically and electrochemically. Compound [1]⁺PF^-₆ has been obtained by oxidation of 1 with AgPF₆, whereas the corresponding AlCl^-₄ salt has been prepared in a one-pot reaction from CpMoCl₂, triphos and AlCl₃. The structure of 1 has been confirmed by X-ray crystallography as a four-legged piano stool with an η⁵-cyclopentadienyl ring and a tridentate triphos ligand. Copyright