Sandwich d/f Heterometallic Complexes [(Ln(hfac) 3 ) 2 M(acac) 3 ] (Ln = La, Pr, Sm, Dy and M = Co; Ln = La and M = Ru).

Sandwich d/f heterometallic complexes [(Ln(hfac) ₃ ) ₂ M(acac) ₃ ] (Ln = La, Pr, Sm, Dy and M = Co; Ln = La and M = Ru) were prepared in strictly anhydrous conditions reacting the formally unsaturated fragment [Ln(hfac) ₃ ] and [M(acac) ₃ ] in a 2-to-1 molar ratio. These heterometallic complexes are highly sensitive to moisture. Spectroscopic observation revealed that on hydrolysis, these compounds yield dinuclear heterometallic compounds [Ln(hfac) ₃ M(acac) ₃ ], prepared here for comparison purposes only. Quantum mechanical calculations supported, on the one hand, the hypothesis on the geometrical arrangement obtained from ATR-IR and NMR spectra and, on the other hand, helped to rationalize the spontaneous hydrolysis reaction.