Université de Fribourg

Formation and Reactivity of [(tacn)-N-CO-Re(III)Br(CO)(2)](+) in Water : a Theoretical and Experimental Study

Zobi, Fabio ; Blacque, Olivier ; Steyl, Gideon ; Spingler, Bernhard ; Alberto, Roger

In: Inorganic Chemistry, 2009, vol. 48, no. 11, p. 4963-4970

The chemistry of [(tacn)-N-CO-Re(III)(CO)(2)Br]X (X = Cl or Br), obtained in good yield from the reaction of fac-[(tacn)Re(I)(CO)(3)]Br (1, tacn = 1,4,7- triazacyclononane) with X(2) in water, is described. The [(tacn)-N-CO-Re(III)(CO) (2)Br]X complex (2 with X = Br(-); 2a with X = BrCl(2)(-)), which we have previously communicated, is characterized by an unusual three-membered ring acyl amide...

Université de Fribourg

Ligand electronic parameters as a measure of the polarization of the C≡O bond in [M(CO)(x)L(y)]n complexes and of the relative stabilization of [M(CO)(x)L(y)](n/n+1) species

Zobi, Fabio

In: Inorganic Chemistry, 2010, vol. 49, no. 22, p. 10370-10377

The electronic description of octahedral (fac-[M(CO)(3)L(3)](n), with M = Re, Ru, and Mn, and [Cr(CO)(5)L](n)), square-planar (cis-[Pt(CO)(2)L(2)](n)), and tetrahedral ([Ni(CO)(3)L](n)) carbonyl complexes (where L = monodentate ligand) was obtained via density functional theory and natural population analyses in order to understand what effects are probed in these species by vibrational...

Université de Fribourg

Parametrization of the contribution of mono- and bidentate ligands on the symmetric C[triple bond]O stretching frequency of fac-[Re(CO)(3)](+) complexes

Zobi, Fabio

In: Inorganic Chemistry, 2009, vol. 48, no. 22, p. 10845-10855

A ligand parameter, IR(P)(L), is introduced in order to evaluate the effect that different monodentate and bidentate ligands have on the symmetric C[triple bond]O stretching frequency of octahedral d(6) fac-[Re(CO)(3)L(3)] complexes (L = mono- or bidentate ligand). The parameter is empirically derived by assuming that the electronic effect, or contribution, that any given ligand L will add to...

Université de Fribourg

Synthesis and reactivity of the 17 e- complex [Re(II)Br4(CO)2]2 : A convenient entry into rhenium(II) chemistry

Zobi, Fabio ; Kromer, Lukas ; Spingler, Bernhard ; Alberto, Roger

In: Inorganic Chemistry, 2009, vol. 48, no. 18, p. 8965-8970

The reduction of (Et(4)N)[Re(III)Br(4)(CO)(2)] (1) by 0.5 equiv of tetrakis- dimethylaminoethylene in acetonitrile yields directly the air-stable, 17-electron Re(II) synthon (Et(4)N)(2)[Re(II)Br(4)(CO)(2)] (2) in nearly quantitative yield. The versatility of 2 as a synthon for Re(II) chemistry was demonstrated by substitution reactions of [Re(II)Br(4)(CO)(2)](2-) with different mono-, bi-,...

Université de Fribourg

Aerobically stable and substitutionally labile α-diimine rhenium dicarbonyl complexes

Schindler, Kevin ; Crochet, Aurélien ; Zobi, Fabio

In: RSC Advances, 2021, vol. 11, p. 7511-7520

New synthetic routes to aerobically stable and substitutionally labile α-diimine rhenium(I) dicarbonyl complexes are described. The molecules are prepared in high yield from the cis–cis–trans-[Re(CO)2(tBu2bpy)Br2]− anion (2, where tBu2bpy is 4,4′- di-tert-butyl-2,2′-bipyridine), which can be isolated from the one electron reduction of the corresponding 17-electron complex (1)....

Université de Fribourg

Insights into the mechanism of photosynthetic H 2 evolution catalyzed by a heptacoordinate cobalt complex

Lucarini, Fiorella ; Fize, Jennifer ; Morozan, Adina ; Marazzi, Marco ; Natali, Mirco ; Pastore, Mariachiara ; Artero, Vincent ; Ruggi, Albert

In: Sustainable Energy & Fuels, 2020, vol. 4, no. 2, p. 589–599

H2 evolution catalyzed by a heptacoordinate complex under both electro- (1) and photo-chemical (2) conditions is analyzed in detail in order to gain insights into the mechanism of the processes. The complex shows high catalytic activity for hydrogen production in acetonitrile, in the presence of trifluoroacetic acid and triethylammonium tetrafluoroborate as proton sources. Foot-of-the-wave...

Université de Fribourg

Design, synthesis and in vivo evaluation of 3-arylcoumarin derivatives of rhenium(I) tricarbonyl complexes as potent antibacterial agents against methicillin-resistant Staphylococcus aureus (MRSA)

Sovari, Sara Nasiri ; Vojnovic, Sandra ; Bogojevic, Sanja Skaro ; Crochet, Aurélien ; Pavic, Aleksandar ; Nikodinovic-Runic, Jasmina ; Zobi, Fabio

In: European Journal of Medicinal Chemistry, 2020, vol. 205, p. 112533

We have prepared a series of ten 3-arylcoumarin molecules, their respective fac- [Re(CO)3(bpy)L]+ and fac-[Re(CO)3(L⁀L)Br] complexes and tested all compounds for their antimicrobial efficacy. Whereas the 3-arylcoumarin ligands are virtually inactive against the human-associated pathogens with minimum inhibitory concentrations (MICs) > 150 μM, when coordinated to the fac-[Re(CO)3]+ core,...

Université de Fribourg

Cytotoxicity of Mn-based photoCORMs of ethynyl-α-diimine ligands against different cancer cell lines: The key role of CO-depleted metal fragments

Rossier, Jeremie ; Delasoie, Joachim ; Haeni, Laetitia ; Hauser, Daniel ; Rothen-Rutishauser, Barbara ; Zobi, Fabio

In: Journal of Inorganic Biochemistry, 2020, vol. 209, p. 111122

A series of tricarbonyl manganese complexes bearing 4-ethynyl-2,2′-bipyridine and 5- ethynyl-1,10-phenanthroline α-diimine ligands were synthetized, characterized and conjugated to vitamin B12, previously used as a vector for drug delivery, to take advantage of its water solubility and specificity toward cancer cells. The compounds act as photoactivatable carbon monoxide-releasing molecules...

Université de Fribourg

Tautomerism and self-association in the solution of new pinene-bipyridine and pinene-phenanthroline derivatives

Solea, Atena B. ; Cornu, Ivan ; Deneva, Vera ; Crochet, Aurélien ; Fromm, Katharina M. ; Antonov, Liudmil ; Allemann, Christophe ; Mamula, Olimpia

In: Molecules, 2020, vol. 25, no. 2, p. 298

Two novel pinene-type ligands have been synthesized and their tautomeric and self- associating behavior studied in solution and in the solid state. The first ligand, an acetylated derivative of 5,6-pinene-bipyridine, displays keto-enol tautomerism in solution. This tautomeric equilibrium was studied by NMR and UV-Vis spectroscopy in various solvents, and the results were compared with the ones...

Université de Fribourg

Correlation of MLCTs of Group 7 fac-[M(CO)3]+ complexes (M = Mn, Re) with bipyridine, pyridinylpyrazine, azopyridine, and pyridin-2-ylmethanimine type ligands for rational photoCORM design

Kottelat, Emmanuel ; Lucarini, Fiorella ; Crochet, Aurélien ; Ruggi, Albert ; Zobi, Fabio

In: European Journal of Inorganic Chemistry, 2019, vol. 2019, no. 33, p. 3758–3768

A mathematical correlation of the MLCT absorption maxima of structurally related fac‐ [M(CO)3L2Br] complexes (M = Mn, Re; L2 = bidentate ligand) is obtained by the comparison of a total of 50 species bearing bipyridine, pyridinylpyrazine, azopyridine and pyridin‐2‐ylmethanimine L2 type ligands. The empirical relationship is first derived by the initial comparison of the MLCT absorption...