Ferrocenyl ligands. Part 1. An analysis of the structures of substituted ferrocenylphosphines to aid in the understanding of the ligand bonding. The crystal and molecular structure of diferrocenylphenylphosphine

Abstract

The crystal and molecular structure of diferrocenylphenylphosphine PPh[C₅H₄Fe(C₅H₅)]₂ has been determined. The central phosphorus atom is in a tetrahedral environment with CPC angles less than ideal as expected for the presence of a phosphorus lone pair. The average angle is ≈100°, which is smaller than the corresponding angle in PPh₃ and 1-(1′-dimethylaminoethyl)-2-(diphenylphos-phino)ferrocene. The causes of such bond-angle distortions are discussed with reference to other related structures and also with respect to the effect on ³¹P n.m.r. chemical shifts. The nature of the interaction between the phosphorus atom and the ferrocenyl moiety can be understood by considering Mössbauer spectra in conjunction with structural data for ferrocenylphosphines and their quaternised derivatives.