Triphospha-Ferrocenes as Ligands. Crystal Structures of [Fe(η⁵-C₅Me₅)(η⁵-C₂^TBu₂P₃)M(CO)₅)], (M= Cr, MO, W) and the Novel ruthenium and Nickel Complexes [Fe(η⁵-C₅Me₅) (η⁵-C₂^TBu₂P₃)Ru₃(CO)₉] and [Fe(η⁵-C₅Me₅)(η⁵-C₂^tBu₂P₃)Ni(Co)₂]₂

Abstract

Syntheses and structures of penta- and hexaphosphorus analogues of ferrocene have been described recently¹. Unlike their simple ferrocene analogues, these complexes have further ligating potential towards other transition metal centres by virtue of the availability of the ring phosphorus lone-pair electrons that are not involved in the η⁵-coordination. We now describe the first examples of coordination compounds of the triphospha-ferrocene [Fe(η⁵-C₅Me₅) (η⁵-C₂ ^tBu₂P₃]. In the ruthenium complex [Fe(η⁵-C₅Me₅)(η⁵-C₂ ^tBu₂P₃) Ru₃(CO)₉] ² two adjacent phosphorus atoms of the η⁵-C₂ ^tBu₂P₃ ring are interlinked by a ruthenium carbonyl cluster in which all three ruthenium atoms interact with the phosphorus atoms. The tetrametallic nickel complex [Fe(η⁵-C₅Me₅)(η⁵-C₂ ^tBu₂P₃)Ni(CO)₂]₂ ³ represents the first example of intermolecular interlinkage of two phospha-ferrocene systems by two metal centres.

Key Words:

• Metal complexes
• phospha-ferrocenes
• 31P NMR spectroscopy
• X-ray crystal structure analysis