| Abstract
| - The ambidentate character of dimethyl sulfoxide, already known for dirhodium carboxylates, has been remarkablymanifested in new ways. Three novel complexes of dirhodium(II) tetra(trifluoroacetate) with the DMSO ligand,namely, [Rh2(O2CCF3)4]m(DMSO)n with m:n = 7:8 (1), 1:1 (2), and 3:2 (3), have been obtained by depositionfrom the vapor phase, and their crystal structures have been determined by X-ray crystallography. Thecrystallographic parameters are as follows: for 1, monoclinic space group P21/c with a = 28.261(2) Å, b =16.059(4) Å, c = 17.636(2) Å, β = 92.40(4)°, and Z = 2; for 2, triclinic space group P1̄ with a = 8.915(2) Å,b = 10.592(2) Å, c = 11.916(2) Å, α = 84.85(1)°, β = 88.86(1)°, γ = 65.187(8)°, and Z = 2; and for 3, triclinicspace group P1̄ with a = 8.876(2) Å, b = 9.017(2) Å, c = 19.841(3) Å, α = 101.91(2)°, β = 97.144(8)°, γ =100.206(9)°, and Z = 1. In the oligomeric molecule of 1, six DMSO ligands bridge seven dirhodium tetra(trifluoroacetate) units in a bidentate fashion via S and O atoms, and two additional DMSO molecules terminatethe chain. In the structure of the monoadduct Rh2(O2CCF3)4(DMSO) (2), the dirhodium blocks are bridged throughthe O atoms of DMSO ligands, forming a one-dimensional polymeric chain. Compound 3 also has an infinitechain structure with the molecules of dimethyl sulfoxide acting in a bidentate μ-DMSO-S,O mode. Every secondDMSO molecule is missing in 3, so that two of every three Rh2(O2CCF3)4 units are associated through the Oatoms of carboxylate groups to give the overall composition [Rh2(O2CCF3)4]3(DMSO)2.
- Three new complexes of dirhodium(II) tetra(trifluoroacetate) with dimethyl sulfoxide, [Rh2(O2CCF3)4]m(DMSO)n, where m:n = 7:8 (1), 1:1 (2), and 3:2 (3), have been obtained by deposition from the vapor phase. The compound 1 has an oligomeric structure, whereas 2 and 3 are zigzag chain polymers. The DMSO acts as a bridging ligand either in bidentate fashion (I) via S and O centers (1 and 3) or in monodentate coordination (II) through its oxygen atom (2).
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