Ruthenium electronic structure

It is assumed that the mechanism proceeds via activation of the imine by the ruthenium catalyst (structure 169), followed by reaction with ethyl diazoacetate to generate a metal-bound ylide intermediate. Intramolecular ruthenium- assisted attack of the carbanion 170 onto the iminium ion provides the corresponding aziridine with moderate to high // selectivity. Imines bearing electron-donating groups (R2) showed significant rate enhancement. 

Contzen J, Kostka S, Kraft R, Jung C. Intermolecular electron transfer in cytochrome P450cam covalently bound with tris(2,2 -bipyridyl)ruthenium(II) structural changes detected by FTIR spectroscopy. J Inorg Biochem 2002 91 607-17. 

First, we will briefly discuss the electronic structure of the copper(I) complex in the excited state, because the electronic structure is less well known than that of the ruthenium(II) complex. In the usual transition-metal complexes, the d-d excited state exists in a lower energy than the MLCT excited state, as shown in Scheme 20A. This feature is not favorable for the electron transfer reaction, as was discussed in Sec. II.B. However, the d-d excited state does not exist in the copper(I) complexes, because the copper(I) atom takes ad10 electron configuration. 

Ruthenium(III), d5 Ru111 is often associated with classical-type ligands, e.g. ammine, water, halides. They are octahedral low spin t2/ species with one unpaired electron and generally sub-stitutionally inert. The electronic structure of polynuclear carboxylates and mixed valence Ru" 1" complexes of the type [Ru(NH3)5]2L5+ has been the subject of much interest particularly with respect to the degree of unpaired electron delocalization within these molecules. 

Monat J. E., Rodriguez J. H. and McCusker J. K. (2002), Ground- and excited-state electronic structures of the solar cell sensitizer bis(4,4 -dicarboxylato-2,2 -bipyridine)bis(isothiocyanato)ruthenium(II), J. Phys. Chem. A 106, 7399-7406. 

Referring to the short Ru-Ru distance, Gibb et al. considered the problem of the electronic structure from a molecular orbital viewpoint [58]. Such a treatment is a poor approximation in this case since it cannot explain the low temperature magnetic behavior, which mainly results from spin-orbit coupling effects. These ones prevail here as seen in other ruthenium(IV) compounds [57]. 

Carbonyl Complexes of the Transition Metals Electronic Structure of Organometallic Compounds Flydride Complexes of the Transition Metals Ligand Field Theory Spectra Manganese Organometallic Chemistry Photochemistry of Transition Metal Complexes Rhenium Organometallic Chemistry Ruthenium Organometallic Chemistry. 

Thiazyl monomer can be stabilized by coordination to a metal, and many thionitrosyl complexes with Cr, Mo, Re, Ru, Os, Co, Rh, Ir, and Ft are known.Comparison of the spectroscopic properties and the electronic structures of M-NS and M-NO complexes indicates that NS is a better a-donor and r-acceptor ligand than NO. Oxygen transfer from an NO2 to an NS ligand on the same metal center occurs in ruthenium porphyrin complexes. ... 

Alkyl ligands are strong a -donors, and coordination of such ligands to metal centers such as rhenium(I) and ruthenium(II) would perturb the electronic structures of the metal centers and give complexes with remarkable photochemical properties. Irradiation of the complexes [Re(CO)3(R)(4,4 -Me2-bpy)j (R = Et, Pr, Bz) into their visible MLCT absorption bands (ca. 400-500 nm) resulted in extremely efficient homolytic cleavage of the Re-R bonds with the formation of the radicals [Re(CO)3(4,4 -Me2-bpy)]- and methyl... 

The d oxidative addition may seem unfamiliar because there are many more examples 47) of d d and d d processes. However, ruthenocene, which is sl (P ruthenium (II) complex with a delocalized electronic structure, undergoes two-electron oxidative addition by I2 and Br2 to give the Ru(IV) complexes Ru(cp)2r and Ru(cp)2Br (48). X-ray studies of Ru(cp)2r show that it is eflFectively a seven-co-ordinate complex (48). 

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