Bimetallic clusters of iron with palladium and platinum.: Synthesis and structures of Fe2(CO)9[M(PBut3)]2 (M = Pd or Pt) and Fe2(CO)8[Pt(PBut3)]2(μ-H)2

The reaction of Fe-2(CO)(9) with Pd(PBu3t)(2) and Pt(PBu3t)(2) yielded the Fe-Pd and Fe-Pt cluster complexes Fe-2(CO)(9)-[M(PBu3t)](2), M = Pd (8) or Pt (9). The structures of 8 and 9 are analogous and consist of nearly planar butterfly clusters of two palladium/platinum atoms in the wing-tip positions and two mutually bonded iron atoms, Fe-Fe = 2.9582(11) angstrom in 8 and 2.9100 (9) angstrom in 9. Compound 8 decomposes to form the mononuclear iron compound Fe(CO)(4)(PBu3t) (11) when heated at 68 degrees C. The reaction of Pt(PBu3t)(2) with Fe-2(CO)(9) in the presence of hydrogen at 127 degrees C yielded the dihydrido complex Fe-2(CO)(8)[Pt(PBu3t)](2)(mu-H)(2) (10). Compound 10 contains a closed Fe2Pt2 tetrahedral cluster with hydrido ligands bridging two of the Fe-Pt bonds. Compounds 8, 9, and 10 were structurally characterized crystallographically.