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A variety of mono- and bisphosphine sulfides and selenides were synthesized and structurally characterized by NMR spectroscopy. In addition, the X-ray crystal structures were determined for eleven of these compounds. The percent buried volume was determined from the X-ray structures and the use of this measurement in estimating the steric bulk in phosphine sulfides and selenides was further developed. The oxidation of the mono- and bisphosphine chalcogenides was examined using cyclic voltammetry in methylene chloride and acetonitrile. The solvent had little effect on the observed trends in the potentials at which oxidation occurred. Both the mono- and bisphosphine chalcogenides display an irreversible oxidative wave. Many of the phosphine selenides also display a follow-up, irreversible reductive wave indicative of the formation of a Se–Se bond upon oxidation. However, the products for the oxidation of the phosphine selenides could not be isolated by chemical oxidation. The potential at which oxidation of the phosphine sulfides occurs is more positive than the analogous phosphine selenides.

New compounds containing the 1,1′-bis(dialkylaminophosphino)ferrocene ligands 1,1′-bis(dimethylaminophosphino)ferrocene (dmapf) and 1,1′-bis(diethylaminophosphino)ferrocene (deapf) were prepared and characterized by NMR. The oxidative electrochemistries of these compounds were examined in methylene chloride. The transition metal compounds M n Cl 2 (P–P) (M = Pd or Pt, n = 1, P–P = dmapf or deapf; M = Au, n = 2, P–P = dmapf) displayed one-electron, Nernstian waves. The corresponding selenides were prepared and the oxidative electrochemistries, along with those of the previously prepared 1,1′-bis(alkylaminophosphine sulfide)ferrocene, were examined. The sulfides displayed one-electron, Nernstian oxidations. The selenides displayed electrochemically irreversible two-electron waves. The X-ray structures of the sulfides and selenides as well as that of the transition metal compounds [(AuCl) 2 (dmapf)] and [PtCl 2 (dmapf)] were determined.

The oxidative electrochemistry of chiral, bidentate ferrocenylphosphines, five Taniaphos and seven Walphos ligands, was studied in methylene chloride. In general, two waves of varying reversibility were observed. Complexes of the general type [(phosphine)MCl2] (phosphine = Taniaphos or Walphos; M = Pd or Pt) were prepared and characterized by NMR. Upon coordination, the oxidative electrochemistry of the ligands was greatly simplified. The X-ray structures of a Taniaphos platinum complex as well as a palladium and a platinum complex with a Walphos ligand were determined.

The preparation of 1,1′-bis(β-hydroxyethyl)ferrocene (1) by oxidation of 1,1′-divinylferrocene is described. Compound 1 has been characterized by 1H and 13C{1H} NMR, and cyclic voltammetry. The electrochemical data are compared to ferrocene and the closely related 2-ferrocenylethanol, 2.