Unusually efficient pyridine photodissociation from Ru(II) complexes with sterically bulky bidentate ancillary ligands.

ABSTRACT: The introduction of steric bulk to the bidentate ligand in [Ru(tpy)(bpy)(py)](2+) (1; tpy = 2,2':2',6″-terpyridine; bpy = 2,2'-bipyridine; py = pyridine) to provide [Ru(tpy)(Me2bpy)(py)](2+) (2; Me2bpy = 6,6'-dimethyl-2,2'-bipyridine) and [Ru(tpy)(biq)(py)](2+) (3; biq = 2,2'-biquinoline) facilitates photoinduced dissociation of pyridine with visible light. Upon irradiation of 2 and 3 in CH3CN (λirr = 500 nm), ligand exchange occurs to produce the corresponding [Ru(tpy)(NN)(NCCH3)](2+) (NN = Me2bpy, biq) complex with quantum yields, Φ500, of 0.16(1) and 0.033(1) for 2 and 3, respectively. These values represent an increase in efficiency of the reaction by 2-3 orders of magnitude as compared to that of 1, Φ500 < 0.0001, under similar experimental conditions. The photolysis of 2 and 3 in H2O

SUBMITTER: Knoll JD 

PROVIDER: S-EPMC4234441 | biostudies-literature | 2014 Nov

REPOSITORIES: biostudies-literature