Electronic properties of new homobimetallic anthracene-bridged η5-cyclopentadienyl derivatives of iridium(I) and of the corresponding cation radicals [L2Ir(C5H4CH2(9,10-anthrylene)CH2C5H4)IrL2]+

摘要: Abstract The bimetallic complexes [L 2 Ir{C 5 H 4 CH (9,10-anthrylene)CH C }IrL ] ( 3 ) (L = η -C and (L = CO) were obtained by reacting the thallium(I) derivative of 9,10-bis(cyclopentadienylmethyl)-anthracene 1 ), i.e. [Tl{C }Tl] with [IrCl(η [IrCl(C N)(CO) ], respectively, characterized elemental analysis, MS, NMR, UV–Vis (290–490 nm) spectroscopy, FT-IR. When excited at wavelengths ranging from 333 to 383 nm, results be fluorescent, while show almost complete quenching anthrylene fluorescence. electrochemical behaviour has been studied compared that monometallic complexes, (η -9-anthrylmethylcyclopentadienyl)-bis(η -ethylene)iridium(I) whose preparation X-ray structure are reported here, already described -9-anthrylmethylcyclopentadienyl)dicarbonyliridium(I) 6 ). study allows interpretation electrode processes gives information about location redox sites along thermodynamic characterization processes. On this basis, intramolecular charge-transfer process between photo-excited anthrylenic moiety one cyclopentadienylIrL unit is suggested a possible route for oxidation [bis(trifluoroacetoxy)iodo]benzene (PIFA) thallium(III) trifluoroacetate (TTFA), produces radical cations + , which, on base their EPR spectra, as average-valence [Ir +1.5 Ir species. DFT calculations spin density distribution confirm allow further insight into such radicals. Differences analogies lying electronic conformational bimetallic, monometallic, cation radicals discussed comparing spectra maps.