The Synthesis and Structure of (1‐(Diphenylphosphino)‐1 ‐ (Phenylthio)Ferrocene)Tricarbonyliron(O) (ptppf)Fe(CO) 3

The complex (ptppf)Fe(CO) 3 has been prepared in high yield by the reaction of ptppf, l‐(diphenyl‐phosphino)‐l'‐(phenylthio)ferrocene, with ( cis ‐cyclooctene) 2 ‐Fe(CO) 3 in THF at −60°C. The complex has been characterized by IR, 31 P NMR, mass spectrometry and single‐crystal X‐ray diffraction. This compound is the first example of a ferrocenyl ligand having both sulfur and phosphorus donor atoms bound to a Fe(CO) 3 moiety. X‐ray crystallography shows that the two cyclopentadienyl rings are approximately eclipsed, a rotation of 13° from exactly eclipsed conformation. The tricarbonyl iron center has a trigonal bipyramidal geometry with sulfur occupying the equatorial site and phosphorus the axial site. Crystals of (ptppf)Fe(CO) 3 are monoclinic, with a = 11.645(2), b = 14.304(1), c = 17.075(2) Å,β = 109.23(3)°, Z = 4, and space group P 2 1 /n. The structure was solved according to the heavy‐atom method and refined by full‐matrix least‐squares procedures to R = 0.037 for 2098 reflections with I ≥ 2.5σ(I).