Pentakis(methoxycarbonyl)cyclopentadiene Chemistry. Some Ruthenium, Osmium and Rhenium Complexes

Abstract

The reaction between Ru(O₂CMe)₂(PPh₃)₂ and HC₅(CO₂Me)₅ affrded orange Ru(O₂CMe)-{ C₅(CO₂Me)₅}(PPh₃)₂, which on standing in methanolic solution in air lost PPh₃ and was converted into purple {Ru(µO₂CMe)[C₅(CO₂Me)₅](PPh₃)}₂O. The C₅(CO₂Me)₅ ligands chelate the ruthenium atoms via two ester carbonyl oxygens. The reaction of RuCl(O₂CMe)(CO)(PPh₃)₂ with Tl[C₅(CO₂Me)₅] in MeCN gave cream [Ru(O₂CMe)(CO)(NCMe)(PPh₃)₂] [C₅(CO₂Me)₅]. The syntheses of [C₅(CO₂Me)₅]¯ salts of the [Ru(C=CHPh)(PPh₃)₂Cp]⁺, [Ru₃H(CO)₁₂]⁺, [Os(NCMe)(PPh₃)₂Cp]⁺, [OsH₂(PPh₃)₂Cp]+ and [Re(CO)₃(NCMe)₃]⁺ cations are also reported.