Ruthenium(II)-bipyrimidine complexes. Spectroscopic and electrochemical properties of a novel series of compounds

Diastereoisomers as probes for solvent reorganizational effects on IVCT in dinuclear ruthenium complexes

“…4 and 5, respectively. The spectral features for the diastereoisomeric forms of the complexes are consistent with previous literature reports for [{Ru(bpy) 2 } 2 (l-bpm)] 4+ [30,[71][72][73][74]88] (as a diastereoisomeric mixture) and [{Ru(bpy) 2 } 2 (l-dbneil)] 4+ [68,69].…”

“…The complexes [{Ru(bpy) 2 } 2 (l-bpm)] 4+ and [{Ru-(Me 2 bpy) 2 } 2 (l-bpm)] 4+ have been synthesized previously [30,48,49,[70][71][72][73][74][75][76][77], either by a thermal method involving the reaction of the cis-[Ru(bpy) 2 Cl 2 ] AE 2H 2 O precursor with bpm in ethylene glycol under reflux, or a microwaveassisted synthetic procedure. In the present case, the latter method was used for the complexes [{Ru(pp) 2 } 2 (l-bpm)] 4+ {pp = bpy, Me 2 bpy, 5,5 0 -Me 2 bpy, Me 4 bpy}, which resulted in comparable yields to those obtained from the thermal methods but with a significant reduction in the reaction times (typically $10 min rather than 2 h for the thermal procedure).…”

“…The electrochemical and spectroelectrochemical characteristics of [{Ru(bpy) 2 } 2 (l-bpm)] 4+ (as a diastereoisomeric mixture) Table 1 Electrochemical data (in mV relative to the Fc + /Fc 0 couple) for the dinuclear complexes [{Ru(pp) 2 have been detailed in a number of previous studies [30,[71][72][73][74][78][79][80][81][82][83].…”

“…In the cathodic region, the first two one-electron reduction processes are localized on the the bridging ligand (i.e., bpm 0/À and bpm À/2À ), due to the stronger p-acceptor nature of bpm relative to the terminal pp ligands [30,[71][72][73][74][78][79][80][81][82][83]. The subsequent reduction processes are localized on the terminal pp ligands.…”

Visible Light Photoredox Catalysis with Transition Metal Complexes: Applications in Organic Synthesis

“…159 Critical to the success of this reaction was the use of the photocatalyst ruthenium(II) tris(bipyrimidine), or Ru(bpm) 3 2+ (Scheme 66). 160 In initial experiments, Ru(bpy) 3 2+ was found incapable of promoting the dimerization of trans -anethole in the absence of an oxidative quenching cycle, while the strongly oxidizing tris(bipyrazyl) analogue Ru(bpz) 3 2+ (see section 3.4) was found to give moderate yields of the adduct 307 . Unfortunately, Ru(bpz) 3 2+ ( E 1/2 *II/I = +1.45 V vs SCE) was also found to oxidize the product 307 ( E 1/2 red = +1.27 V vs SCE), leading to cycloreversion and preventing the isolation of 307 in high yields.…”