Bismuth complexes containing Mn(CO)5 and Re(CO)5 fragments. Synthetic studies and structural characterisation by solid- and solution-state extended X-ray absorption fine structure spectroscopy

Abstract

The reaction between BiCl₃ and 3 equivalents of Na[Re(CO)₅] affords the complex [Bi{Re(CO)₅}₃]2, which is compared with the known [Bi{Mn(CO)₅}₃]1. The dimetal complexes [BiCl{M(CO)₅}₂](M = Mn, 3 or Re, 4) were prepared from reactions between BiCl₃ and 2 equivalents of the corresponding metal carbonylate anion. The reaction between compound 1 or 2 and 0.5 equivalent of BiCl₃ affords 3 and 4 respectively whilst the reaction between either 3 and 1 equivalent of BiCl₃ or between BiCl₃ and 1 equivalent of Na[Mn(CO)₅] affords a compound formulated as [BiCl₂{Mn(CO)₅}]5. The syntheses of the bromide and iodide complexes [Bix{Mn(CO)₅}₂](X = Br, 6 or I, 7) are also described. In addition, solution infrared studies are reported on the time- and concentration-dependent decomposition of 3 in tetrahydrofuran (thf) together with details of a number of reactivity studies involing 3. Analysis of Bi-L_III edge and Mn-K edge extended X-ray absorption fine structure spectra for compounds 3 and 4 in solid and solution phases show evidence for oligo- or polymerisation through Bi ⋯ Cl interactions in the solids. In a thf solution of 3 these interactions are disrupted, and the monomeric species formed shows co-ordination of solvent to bismuth.