Ruthenium 6 2+ photochemistry

Campagna S, Puntoriero F, Nastasi F, Bergamini G, Balzani V (2007) Photochemistry and Photophysics of Coordination Compounds Ruthenium. 280 117-214 Campagna S, see Balzani V (2007) 280 1-36... 

Increasing attention is being given to the reactivity of ruthenium species which show unusual behavior compared with their Co analogs. Aspects of current interest are mixed valence states, ruthenated proteins to probe electron transfer in them (Chap. 5) and the photochemistry and photophysics of Ru(II) polypyridine eomplexes. 

The photochemical studies of transition metal hydride complexes that have appeared in the chemical literature are reviewed, with primary emphasis on studies of iridium and ruthenium that were conducted by our research group. The photochemistry of the molybdenum hydride complexes Mo(tj5-C5H5)2M2] and [MoH4(dppe)2] (dppe = Ph2PCH2CH2PPh2), which eliminate H2 upon photolysis, is discussed in detail. The photoinduced elimination of molecular hydrogen from di-and polyhydride complexes of the transition elements is proposed to be a general reaction pathway. 

Mo(r75-C5H5)2H2] and [MoH dppe ]. Our studies of the di- and trihydride complexes of ruthenium and iridium, described above and published previously (27,35), and those of other workers (discussed at the beginning of this chapter), indicate that photoinduced elimination of molecular hydrogen is a common reaction pathway for di- and polyhydride complexes. To demonstrate the photoreaction s generality and its utility for generating otherwise unattainable, extremely reactive metal complexes, we have begun to study the photochemistry of polyhydride complexes of the early transition metals. We focused initially... 

Most photosensitizers, however, are reasonably photostable compounds, and their optical properties have been studied in depth. In particular, there has been much interest in ruthenium-based photosensitizers such as [Ru(bpy)3]2+ and [Ru(phen)3]2+, due to their stability and absorption of visible light. Detailed information on their optical properties, including ground and excited state information in relation to photosensitization, has been reviewed by Creutz et al. [16]. Similarly, the photochemistry and photophysics of rhenium complexes, as discussed here, have been reviewed in detail by Kirgan et al. [7]. 

In the most congested case, (Ru(terpy )(dmp)(CH3SCH3)2+), the photosubstitution quantum yield was shown to be

room temperature in pyridine, which is an extremely high value in ruthenium(II) photochemistry. The control of the bulkiness of the spectator chelates, leading to the control of the congestion of the complex and, hence, to the efficiency of ligand photoexpulsion, is a specific feature of the Ru(terpy)(phen)(L)2+ core. This... 

Szacilowski K, Macyk W, Stochel G, Stasicka Z, Sostero S, Traverso O. Ligand and medium controlled photochemistry of iron and ruthenium mixed-ligand complexes prospecting for versatile systems. Coord Chem Rev 2000 208 277-97. 

Photochemical methods offer a convenient tool to study intra- and interprotein ET because of their time resolution and selectivity. Various mechanistic and design approaches based on photochemistry of metal complexes have been undertaken. Most of the studies on protein electron transfer processes have been done for hae-moproteins using among others ruthenium complex as a photosensitizer, modified haemoproteins in which haem iron is substituted by another metal (mainly Zn), and CO-bonded haem proteins [6,7],... 

Photochemistry of Ru(CO)3(PMe3)2 and the ruthenium(II) compound Ru(CO)2(PMe3)2H2 in low-temperature matrices affords [Ru(CO)2(PMe3)2—S] (S = Ar, Xe, CH4) [61bj. These monomers all have 18-electron tbp structures. 

Smface modification with ruthenium complexes has proven valuable in studies of both interprotein and intraprotein electron transfer in systems that are difflcult to stndy by traditional kinetic tools. The choice of ruthenium complexes in these investigations stems from an extensive photochemistry as well as exceptional thermal stability. The photochemistry provides a means of examining reactions over a time range of nanoseconds to seconds by laser-flash photolysis and the thermal stability allows researchers to covalently bind a wide variety of complexes to proteins with... 

A rich chemistry has flourished in the search for new luminescent systems see Luminescence and Luminescence Behavior Photochemistry of Organotransition Metal Compounds). A great variety of inorganic architectures have been obtained, including helicates and large multicomponent arrays. As an example, rack-type polynuclear ruthenium... 

Asymmetric Synthesis by Homogeneous Catalysis Coordination Chemistry History Coordination Organometallic Chemistry Principles Dihydrogen Complexes Related Sigma Complexes Electron Transfer in Coordination Compounds Electron Transfer Reactions Theory Heterogeneous Catalysis by Metals Hydride Complexes of the Transition Metals Euminescence Luminescence Behavior Photochemistry of Organotransition Metal Compounds Photochemistry of Transition Metal Complexes Ruthenium Organometallic Chemistry. 

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