Crystal structure of μ-carbonyl-1:2κ2C:C-carbonyl-1κC-(1η5-cyclopentadienyl)iodido-2κI-[μ-2-(pyridin-2-yl)ethene-1,1-diyl-1κC1:2κ2N,C1]ironpalladium(Fe—Pd) benzene monosolvate

The reaction of Cp(CO)2FeI with 2-ethynylpyridine under Sonogashira conditions [5% PdCl2(PPh3)2, 10% CuI, THF–NEt3 (2:1)] afforded the title binuclear μ-pyridylvinylidene FePd complex (FePd1) as a benzene solvate, [FePd(C5H5)(C7H5N)I(CO)2]·C6H6, in a very low yield rather than the expected iron o-pyridylethynyl complex Cp(CO)2Fe—C[triple-bond]C-(2-C5H4N). The Fe and Pd atoms in FePd1 are bridged by carbonyl and pyridylvinylidene ligands, the pyridyl N atom being bonded to the palladium atom. The use of equimolar amounts of PdCl2 increases the yield of FePd1 to 12%. The reaction pathway leading to FePd1 is proposed