Bipyridyl photochemistry

There is a brief but eomprehensively referenced section on iron in a review of homoleptie 2,2-bipyridyl eomplexes " iron-terpy (3 pages) and iron-quaterpy (1/2 page) complexes have also been briefly reviewed." Absorption spectra and photochemistry of apprcmriate iron diimine complexes are ineluded in a text on polypyridyl and porphyrin complexes." A review of the applieation of ehiral 2,2 -bipyridines, 1,10-phenanthrolines, and 2,2 6, 2"-terpyridines in homogeneous eatalysis eontains a little material on iron complexes of such ligands." ... 

Keywords Bipyridyl Energy transfer Osmium complexes Osmium photochemistry Osmium photophysics Photosubstitution Terpyridyl... 

Photophysical properties have been recorded for the low-lying emissive MLCT excited state of cis-[Ru(bipy)2L2f [where L = pyridine, pyrazidine, (l,10-phenanthroline) 2, (2,2 -bipyridyl),2, N-methylimidazole, or 2-(2-aminoethyl)pyridine]. The roles of different decay pathways in determining excited-state lifetimes have been examined, and the absence of room-temperature emission and/or the appearance of ligand-loss photochemistry in cases where L = PPh, AsPhj, or Co can all be accounted for in terms of the role which the ligands L play in stabilizing the MLCT state relative to the dd... 

Kalyanasundaram, K. Photophysics, photochemistry and solar energy conversion with tris (bipyridyl)ruthenium(II) and its analogues. Coord. Chem. Rev. 1982, 46, 159-244. 

A different example of complementarity is explored in this chapter. We report studies of a bifunctional redox protein maquette based on the triple-helix bundle design of Ghadiri, Sasaki, and co-workers (4-S). Attempts to monitor electron transfer from an N-terminal ruthenium tris-bipyridyl excited state were fruitless, since electron transfer could not compete with the excited state decay of the Ru(IP) tris-bpy. However, as described below, replacement of photoactive ruthenium by a radiolytically accessible Co couple has allowed initial exploration of electron transfer in this synthetic protein couple. In turn, photochemistry initiated at the viologen chromophore helped confirm and extend the radiolytic results. 

Chromium, tris(bipyridyl)-ligand field photochemistry, 398 photochemistry excited states, 398... 

Bipyridine, phenanthroline, and related ligands are classics of redox- and photochemistry and are found in many applications. A very useful compilation of references, synthesis, UV-absorption spectroscopy, and electrochemical data of ruthenium tris-bipyridyl complexes and derivatives has been published [72]. Also compiled in this account is a... 

Ruthenium is another of the rarer metals whose chemistry continues to flourish. A possibly important method of storing solar energy comes from recent studies of the photochemistry of tris-(bipyridyl)ruthenium(n) complexes ... 

Kalyanasundaram, K. Photophysics, Photochemistry and Solar Energy Conversion with Tris(Bipyridyl)ruthenium(ll) and its Analogues, Coord. Chem. Revs. 1982,46,159-244. 

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