Electrochemistry of phosphaferrocenes. 1. Comparison of the redox properties of ferrocene, diphosphaferrocene, 3,4-dimethyl-1-phosphaferrocene and 3,3',4,4'-tetramethyl-1,1'-diphosphaferrocene

The synthesis, structures, and electrochemistry of 1′-heteroaryl-2,5-dimethylazaferrocenes

“…Research into heteroatom substituted ferrocenes has consequently addressed issues such as the influence of heteroatom substitution of CH groups on the redox potentials and on the chemical stabilities of the associated radical cations. In the group 15 series of ferrocene derivatives there is a general consensus that incremental CH substitution by P or N increases E 1/2 and renders the associated cations more susceptible to nucleophilic attack or deprotonation [34][35][36][37]. Quantum mechanical studies on aza-and phosphaferrocenes disclosed that sequential heteroatom incorporation induces some charge shift from the iron and the remaining cyclopentadienyl ring to the p-coordinated heterocycle and thus increases the potential of the still iron based oxidation [38].…”

Phospha‐Organic Chemistry: Panorama and Perspectives

“…Electrochemical studies of phosphaferrocenes show that the switching a CH group for a phosphorus atom in ferrocenes favors reduction and disfavors oxidation. [280] The first structurally characterized phosphaferricinium salt has only recently been described. [281] The replacement of a Cp unit by a phospholyl ligand in any h 5 complex confers electronic stabilization upon the reduced species.…”

Lithiation and alkylation reactions of the tri-phosphaferrocenes, [Fe(η5-P3C2tBu2)(η5-C5R5)], (R=H and Me): Crystal and molecular structures of the LiFe(η4-P2C2tBu2PnBu)(η5-C5Me5)2 dimer, [Fe(η4-P2C2tBu2PnBuMe)(η5-C5Me5)] and cis-[PtCl2(PMe3)Fe(η4-P2C2tBu2PnBuMe)(η5-C5H5)]

“…The nature of the bonding in phosphaferrocenes and related phosphametallocenes containing the g 5 -ligated 3,5-ditertiarybutyl-1,2,4-triphospholyl ring system, has been explored by electrochemical measurements in solution and gas-phase photoelectron spectroscopic techniques, coupled with supportive DFT calculations [12,21,22]. These studies have established that replacement of CR fragments by P in the corresponding parent metallocene reduces the overall electron density at the metal centre.…”