71964-17-5Relevant academic research and scientific papers
Thermal and photochemical properties of some trans-disubstituted tetraammineruthenium(II) complexes of aromatic nitrogen heterocycles, trans-Ru(NH3)4LL′n+
Tfouni, Elia,Ford, Peter C.
, p. 72 - 76 (2008/10/08)
Reported are the syntheses and other solution properties of several disubstituted ruthenium(II) amine complexes trans-Ru(NH3)4LL′n+ (L = pyridine (py), L′ = pyrazine (pz), pyrazinium (pzH+), or 4-acetylpyridine (4-ac-py); L = L′ = pz, pzH+). The visible range spectra of these species each display two metal-to-ligand charge-transfer absorptions, the lower energy transition being the much more intense. However, the higher energy charge-transfer band is especially prominent when L ≠ L′. The aqueous solution basicities of the coordinated pz in these complexes have been determined, and when earlier data are included, the basicity order Ru(NH3)5pz2+ > trans-Ru(NH3)4(py)pz2+ > trans-Ru(NH3)4pz22+ > free pyrazine > trans-Ru(NH3)4(pzH)pz3+ > Ru(NH3)5pz3+ is obtained. Visible range photolyses of the trans-Ru(NH3)4LL′n+ ions in aqueous solution lead predominantly to the photoaquation of coordinated ammonia. The relative quantum yields of these photoreactions show patterns consistent with the excited-state tuning model proposed to explain photochemical properties of the pentaammine analogues Ru(NH3)5L2+.
