Cationic ruthenium systems. Part 4. Bridge-splitting reactions of the triply bridged dimers bis(η-cyclo-octa-1,5-diene)(NN-dimethylhydrazine)dihalogenodihydridodiruthenium with a series of neutral donor ligands

Abstract

The triply bridged complexes [{RuX(H)(cod)}₂(NH₂NMe₂)](2; X = Cl or Br; cod = cyclo-octa-1,5-diene), containing H, X, and NH₂NMe₂ as bridging ligands, have been prepared from [RuH(cod)(NH₂NMe₂)₃]A (1; A = PF₆ or BPh₄) and LiX in moderate yields from acetone–methanol mixtures. The mother liquors of these reactions produced [Ru₃(CO)₁₂] and [RuX(H)(PPh₃)₃] with CO and PPh₃ respectively. Complexes (2) undergo bridge-splitting reactions with a series of neutral donor ligands to produce [RuX(H)(cod)L₂][3; L = PMePh₂, SbPh₃, AsPh₃, or pyridine (py)], [RuCl(H)(PPh₃)₃], [RuH{PPh(OMe)₂}₅][PF₆], [RuH(cod)L₃]⁺(L = 4Me-py or NCMe), and [RuCl₂(4Me-py)₄]. Infrared and ¹H n.m.r. data for the complexes are discussed.