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A rhodium(I) dicarbonyl on HY zeolite prepared from [Rh(CH 3 COCHCOCH 3 )(CO) 2 ] were charaterised by Attenuated Total Reflectance Fourier Transformed Infrared (ATR FTIR) and X-ray Photoelectron Spectroscopy (XPS). The ATR FTIR spectra of the anchored rhodium complex showed that [Rh(CH 3 COCHCOCH 3 )(CO) 2 ] reacted with the HY zeolite by loosing the [CH 3 COCHCOCH 3 ] − ligand to form Rh(CO) 2 /HY zeolite and [CH 3 COCHCOCH 3 ]/HY zeolite. The sharpness of the v (CO) bands measured by the ATR FTIR showed that the rhodium(I) dicarbonyl complex are distributed fairly uniform over the zeolite support. This heterogeneous catalyst was monitored for the oxidative addition of methyl iodide in the liquid phase, followed by reductive elimination of acetyl iodide upon treatment with CO gas. These reactions were monitored by following the carbonyl stretching frequencies from ATR FTIR measurements and the change in binding energy of the Rh 3d 5/2 photoelectron line as measured by XPS, observed rate constants determined were mutually consistent with each other. [ABSTRACT FROM AUTHOR]

Abstract: Chalcones of the type Mc-CO–CH-CO–CH Mc-CO–CHh Mc=Fc=ferrocenyl or Rc=ruthenocenyl, and Ph=phenyl were synthesized. Synthesis was achieved by base catalyzed Claisen–Schmidt condensation of the appropriated acetyl and aldehyde in ethanol. Cyclic voltammetry in CH3CN in the presence of 0.1moldm−3 [N(Bu)4][PF6] revealed chemical and electrochemical reversible behaviour for the Fc/Fc+ couple and irreversible electrochemistry for the two electron Rc/Rc2+ couple. The potential ranges for the Fc/Fc+ couple varied in the range 138⩽ E°′⩽302mV while E pa for Rc/Rc2+ couple was between 358 and 510mV vs. FcH/FcH+, the internal standard. Chalcones with the carbonyl group adjacent to the metallocene, are more difficult to oxidize. [Copyright &y& Elsevier]

Abstract: The synthesis of a variety of tetrahedral β-diketonato titanium(IV) complexes of the type with R=CF3, OCH3, C6H5, CH3 and Fc is described. The TiIII/TiIV couples and the Fc/Fc+ couple exhibited chemically and electrochemically reversible cyclic voltammetric behaviour. The formal reduction potential of the TiIII/IV couple increased as the group electronegativity of the R group of the β-diketonato ligand increased. Bulk electrolysis showed that one electron was transferred in the TiIII/IV couple and one electron in the ferrocenyl/ferrocenium redox couple in the ligand. The crystal structure for the R=OCH3 complex showed that this β-keto-ester binds through the carbonyl oxygen of the ester group and not the ether oxygen. [Copyright &y& Elsevier]

Abstract: Enhanced electrochemical resolution of anodic processes is possible in the presence of [N( n Bu)4][B(C6F5)4], 1, as supporting electrolyte over that obtained in the presence of [N( n Bu)4][PF6]. By changing the anion of the supporting electrolyte to a salt having [B(C6F5)4]−, anions, electrochemical processes of especially cationic analytes can benefit. Thus, the redox chemistry of 0.5mmoldm−3 solutions of [Ru2(μ-FcCOO)4·(CH3CH2OH)2][PF6], 2, Fc=ferrocenyl, in CH2Cl2/[N( n Bu)4][B(C6F5)4] were found to involve four well-resolved ferrocenyl-based electrochemical reversible redox processes as well as reduction of RuIII–RuII. At 1.0mmoldm−3 concentrations of 2, or in the presence of [N( n Bu)4][PF6], the four ferrocenyl processes coalesced into only two waves as a result of (Fc+)⋯() ion paring. Seventeen of the possible 18 one-electron transfer processes of the biscadmium trisphthalocyaninato complex [Cd2{Pc(C6H13)8}3], 3, could be observed in THF/[N( n Bu)4][B(C6F5)4], but the electrochemical window of CH2Cl2/[N( n Bu)4][B(C6F5)4] only allowed detection of 15 of these processes. Although reduction processes were unaffected, THF solvation leading to species such as (3 n +)(THF) x with 1⩽ n ⩽4 and x ⩾1 as well as ion pair formation of the type (3 n +)⋯() prevented good resolution of oxidation processes. The CH2Cl2/[N( n Bu)4][B(C6F5)4] system also allowed detection of reversible one-electron transfer ferrocenyl (Fc/Fc+) and ruthenocenyl-based (Rc/Rc+) processes for both enol and keto isomers of the β-diketone FcCOCH2CORc, 4, Rc=ruthenocenyl. In CH3CN/[N( n Bu)4][PF6], the ruthenocenyl moiety was oxidised to a RuIV species. [Copyright &y& Elsevier]

Graphical abstract The electrochemical behavior of the Fc/Fc+ of ferrocenyl-terpyridine coordination metal complexes is related to the charge transfer and binding energy of the Fe 2p photoelectron lines as measured by XPS, giving insight into the electronic properties of the complexes. Highlights • Preparation of coordinated ferrocenyl-terpyridine complexes. • Electrochemical study of the coordinated ferrocenyl-terpyridine complexes. • X-ray photoelectron spectroscopy of ferrocenyl-terpyridine coordination complexes. • The intensity of satellite structures in XPS indicated the amount of charge transferred. • Single crystal structure of [Rh(Fctpy) 2 ][PF 6 ] 3. Abstract A series of 4′-ferrocenyl-2,2′:6′,2′'-terpyridine coordination metal complexes, [M(Fctpy) 2 ][PF 6 ] x with M = Co (2), Fe (3), and Rh (4) and x = 2 (for 2 and 3) or 3 (for 4), was subjected to an electrochemical and X-ray photoelectron spectroscopic study. The formal reduction potential of the Fc/Fc+ couple of the ferrocenyl-moiety (FeII) is related to the Allred Rochow electronegativities of the different coordinated metals, as well as with binding energies of the Fe 2p 3/2 photoelectron lines (as measured by XPS). The binding energy position of the main Fe 2p 3/2 photoelectron line, spin–orbit splitting between the main and satellite structure (charge transfer band) of the Fe 2p 3/2 photoelectron line as well as the intensity ratio between the of the main and satellite structure of the Fe 2p 3/2 photoelectron line (I ratio , this gives the relative amount of charge being transferred) gave insight in the electronic structure of these ferrocenyl-terpyridine coordination metal complexes, 2 – 4. A single crystal X-ray structure determination of 4 highlighted the disorder of the PF 6 counter anions as well as double occupancy of the central metal atom of Rh (in 4) with Fe, the Fe:Rh ratio is 0.14:0.85. [ABSTRACT FROM AUTHOR]