Bimetallic sandwiches based upon phosphole ligands

Article abstract of DOI:10.1021/ic50223a022

The reaction of a phosphole (L) with a σ,π complex L'Fe₂(CO)_n (L′ = another phosphole; n = 6 or 7) gives the metallic sandwich L[Fe₂(CO)₄]L′. A heterobimetallic sandwich is also obtained when L′FeMo(CO)₈ is the starting compound. The X-ray crystal structure of the complex with L = L′ = 1-phenyl-3,4-dimethylphosphole has been determined. Crystal data: monoclinic, C2/c, with a = 14.334 (1) A?, b = 12.375 (1) A?, c = 16.470 (1) A?, β = 112.62 (1)°. The two phosphole rings adopt a head to tail disposition and are strongly folded. Very large ³¹P-³¹P NMR coupling suggests a direct through-space interaction between the nonbonded phosphorus and iron atoms.