Visible-light ruthenium photoredox

Polypyridine ruthenium (II) chelate complex [Ru (Bpy) ] is known to participate in a photoredox reaction on excitation with visible light, coupled with the... 

Photoredox Organocatalysis. Photoredox catalysis is emerging as an extremely powerful tool in organic synthesis [103]. Photoredox catalysis relies on the ability of some compounds, such as ruthenium(II) tris(bipyridyl) complex (Ru(bipy)3 ), to absorb visible light affording a relatively kinetically stable excited species (usually in the triplet state) with enhanced redox properties (Scheme 2.22). 

Ruthenium (II) polypyridyl complexes promote the photoredox reactions such as Diels-Alder reaction (see formulae 29 31) and azomethine ylide formation followed by [3 + 2] cycloaddition (32-34) by use of visible light. Yoon found 2,2 -bipyrazine ligand is better than 2,2 -bipyridine. Bach reported enantioselective intramolecular [2 + 2] and intermolecular [3 + 2] photocycloaddition by use of chiral hydrogen bond templates (37) and (41). ... 

This topic is detailed in the chapter Visible-light-induced Redox Reactions by Ruthenium Photoredox Catalyst by Akita and Koike. 

Visible-Light-Induced Redox Reactions by Ruthenium Photoredox Catalyst... 

Abstract Photoredox catalysis by well-known nithenium(II) polypyridine complexes is a versatile tool for redox reactions in synthetic organic chemistry, because they can effectively catalyze single-electron-transfer (SET) processes by irradiation with visible light. These favorable properties of the catalysts provide a new strategy for efficient and selective radical reactions. Salts of tris(2,2 -bipyridine)mthenium (II), [Ru(bpy)3], were first reported in 1936. Since then, anumber of works related to artificial photosynthesis and photofunctional materials have been reported, but only limited efforts had been devoted to synthetic organic chemistry. Remarkably, since 2008, this photocatalytic system has gained importance in redox reactions. In this chapter, we will present a concise review of seminal works on ruthenium photoredox catalysis around 2008, which will be followed by our recent research topics on trifluoromethylation of alkenes by photoredox catalysis. 

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