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The electronic structure of several mono(1,1′-diamidoferrocene) uranium complexes (NNR)UX2 (NNR = fc(NR) 2, fc = 1,1′-ferrocenediyl, R = SiMe3, Si tBuMe2, SiMe2Ph, X = I, CH2Ph), (NNTBS)UI(OAr) (OAr = 2,6-di-tert-butylphenoxide), and (NN TBS)U(CH2Ph)(OAr) was investigated by electrochemistry, electronic absorption and vibrational spectroscopy, and DFT calculations. Similar metrical parameters were observed for (NNTBS)U(CH 2Ph)2 and (NNDMP)U(CH2Ph) 2 (and also for the previously reported (NNTMS)UI 2(THF), (NNTBS)UI2(THF), and (NN TBS)U(CH2Ph)(OAr)) that translate in similar DFT parameters (bond orders, metal charges) despite some small differences observed by electrochemistry and IR or electronic absorption spectroscopy. © 2013 American Chemical Society.

The reaction of [Pd(dtbpf)Cl2] (dtbpf = 1,1′-bis(di-tert-butylphosphino)ferrocene)with a chemical oxidant ledunexpectedly to the formation of [Pd(dtbpf)Cl]+. Furtherstudy found that a variety of reagents could be used to abstract achloride ligand from [Pd(dtbpf)Cl2] to yield [Pd(dtbpf)Cl]+. The solid-state structure suggests the formation of an Fe–Pdinteraction. The presence of the bulky tert-butylgroups is essential, as similar reactions with [Pd(PP)Cl2] (PP = other 1,1′-bis(phosphino)ferrocene ligands) resultsin the formation of [Pd(PP)(μ-Cl)]22+.The analogous platinum compounds have also been investigated and appearto behave in a similar manner. Similar compounds of the type [M′(PP)(PR3)]2+(M′ = Pd, Pt, R = Ph, Me) have beenprepared, and a metal–metal interaction has also been observed.Steric and electronic effects dictate the formation of these compounds.X-ray crystal structures were obtained for eight of these compoundsand were used as the basis for a computational analysis of the metal–metalinteraction. DFT analysis indicates the presence of a weak, noncovalentinteraction between the two metal centers. The electrochemical propertiesof these compounds were examined by cyclic voltammetry and typicallyshow one oxidative wave and either one two-electron or two one-electronreductive waves. [ABSTRACT FROM AUTHOR]