Bimetallic iron–rhodium anionic carbonyl clusters: [Fe2Rh(CO)x]–(x= 10 or 11), [FeRh4(CO)15]2–, [Fe2Rh4(CO)16]2–, and [FeRh5(CO)16]–

Abstract

The synthesis and chemical behaviour of the new iron-rhodium anionic carbonyl clusters [Fe₂Rh(CO)_x]^–(x= 10 or 11), [FeRh₄(CO)₁₅]^2–, [Fe₂Rh₄(CO)₁₆]^2–, and [FeRh₅(CO)₁₆]^– are reported. Low-temperature multinuclear n.m.r. studies (¹³C,¹³C-{¹⁰³Rh}, and ¹⁰³Rh) on the penta- and hexa-nuclear clusters allow their structures in solution to be unambiguously established and their fluxional behaviour has been investigated through variable-temperature measurements. None shows rearrangement of the metal polyhedron.