Synthesis and characterization of polypiridine-based rhenium(I) complexes with pyrazino[2,3-f][1,10]phenanthroline

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Díaz Harris, Ramiro
Francois Cifuentes, María Angélica
Leiva, A.M.
Loeb, B.
Norambuena, E.
Yañez, M.
Datos de publicación:
Helvetica Chimica Acta, Vol.89, N°6, 1220-1230, 2006
Síntesis química - Química
A series of tricarbonyl rhenium(I) complexes of the type fac-[Re 1(CO)3(Ppl)(L)]0/+, where ppl is pyrazino[2,3-f][1,10]phenanthroline, and where L is Cl-, TIO -, 4-(tert-butyl)pyridine (tBu-py), 4-methoxypyridine (MeO-py), 4,4′-bipyridyl (bpy), or 10-(picolin-4-yl)phenothiazine (pptz), were synthesized and fully characterized. In all complexes, an increment in the electron-acceptor properties of ppl compared to the free ligand was observed. This effect was more significant for pyridine-type ligands, especially for pptz, compared to Cl- or TfO-. The properties of fac-[Re(CO)3(ppl)(pptz)]PF6 were compared with those of the analogous compound fac-[Re(CO)3(dppz)(pptz)]PF6, where dppz is dipyrido(3,2-a: 2′,3′-c)phenazine, the goal being to generate long-lived excited charge-transfer (CT) states. In this respect, fac-[Re(CO)3(ppl)(pptz)]PF6 seems to be a promising candidate.