Quantum yield of formation of the lowest excited state of Ru(bpy)2+3 and Ru(phen)2+3

Temperature response of luminescent tris(bipyridine)ruthenium(II)-doped silica nanoparticles

“…The noted difference is in line with the fact that DLS measures hydrodynamic diameters, but it may also reflect swelling of the dispersed Stöber's spheres [20]. MLCT triplet that decays via radiative and non-radiative pathways [21,22]. The steady-state emission spectrum of Ru(bpy) 3 @SiO 2 NPs dispersed in water is shown in Fig.…”

Dual Hypervalent Iodine(III) Reagents and Photoredox Catalysis Enable Decarboxylative Ynonylation under Mild Conditions

“…When benzoylformic acid (1)w as injected into the reaction condition in the absence of BI-alkyne 50,the formation of the decarboxylative diketone adduct through dimerization further confirmed the acyl radical intermediate (see Scheme S3 in the Supporting Information). [18] We next tested another effective oxidative quencher of photoexcited Ru II *species to study the role of BI-OAc.Interestingly,with 1.0 equivalent of potassium persulfates, [19] ynone 3 was obtained only in 38 %y ield with side products after an extended 24 hr eaction time (Scheme 2b). In contrast, BIOAcgreatly accelerated the reaction, and acatalytic amount (0.1-0.6 equivalent) of BI-OAc was sufficient to yield ynone 3 in 59-79 %y ield in 1h with clean conversions.W hen the reaction time was extended to 8h,0 .1 equivalent of BI-OAc was sufficient to yield ynone 3 in 81 %y ield, which implied the catalytic role of BI-OAc (Scheme 2b).…”

“…Heterocyclic thiophenes,f urans,a nd indoles reacted smoothly to give ynones [17][18][19].N otably,a lkyl-substituted ketoacids decarboxylated to give coupling adducts:P rimary and secondary alkyl ketoacids gave ynones without decarbonylation in 66 %a nd 82 % yields,r espectively (20,21), while the tertiary alkyl ketoacid gave the dual decarboxylative-decarbonylative alkyne coupling adduct 22 in 73 %y ield. [15] In addition to aryl-and alkyl-substituted a-ketoacids,c arbamoyl ketoacids readily reacted to give ynamides:P rimary carbamoyl ketoacids reacted to give,inyields of 61-69 %, primary ynamide products, which could not be obtained by transition-metalcatalyzed aminocarbonylation because of the catalytic inhibition of primary amines by transition metals (23)(24)(25)(26)(27)(28).…”

CeIV‐ and Light‐Driven Water Oxidation by [Ru(terpy)(pic)3]2+ Analogues: Catalytic and Mechanistic Studies

“…The involvement of seven-coordinate ruthenium intermediates in water oxidation is of interest, and was first predicted by density functional theory (DFT) calculations by Meyer, Thummel, and co-workers, [14,15] and then experimentally demonstrated by the isolation of a seven-coordinate Ru IV intermediate based on the complex RuL(pic) 2 (H 2 L = 2,2'-bipyridine-6,6'-dicarboxylic acid, pic = 4-picoline) in our group. [16] Owing to the stabilization of high-valent ruthenium states by the negatively charged ligand, 2,2'-bipyridine-6,6'-dicarboxylate, light-driven water oxidation was achieved by using a three-component system comprising a rutheniumbased photosensitizer ([Ru(bpy) 3 ] 2 + (E 1/2 = 1.26 V; bpy = 2,2'-bipyridine) and/or even [Ru(dmbpy) 3 ] 2 + (E 1/2 = 1.10 V; dmbpy = 4,4'-dimethyl-2,2'-bipyridine)), a sacrificial electron acceptor (e.g., S 2 O 8 2À ; E 0 (S 2 O 8 2À /SO 4 2À +SO 4 À ) 0.6 V), [17] and the WOC RuL(pic) 2 . [18] In 2008, Thummel and co-workers reported a readily obtainable mononuclear ruthenium complex, [Ru(terpy)(pic) 3 ](PF 6 ) 2 (1; terpy = 2,2';6',2"-terpyridine) capable of catalyzing Ce IV -driven water oxidation.…”