Ruthenium carbonyl porphyrins

A number of unusual structural features have been noted. The ruthenium porphyrin formed by reaction of triruthenium dodecacarbonyl with an N, AT-vinyl-bridged tetraphenylporphyrin involves disruption of a pyrrole C-N bond to give a product in which the ruthenium is bound to two pyrrole N atoms, the C and N atoms of the ruptured pyrrole ring, and two mutually cis carbonyl ligands. The remaining pyrrole N is uncoordinated.613 Mutually cis configurations have also been found for the dicarbonyl complex of molybdenum tetraphenylporphyrin and for some dinitrosyl porphyrins. 

Recently, ruthenium porphyrins have been used as catalysts for tandem carbonyl yhde formation/cycloaddition transformation [200,201]. The dia-stereoselectivity of the reaction with a variety of alkyl- and aryl-substituted a-diazo ketones was found to be highly substrate-dependant. Finally, highly selective intra- and intermolecular couphng reactions of diazocompounds to form cis-alkenes, including organic macrocychc compounds were developed by Che et al. [202]. 

Fig. 3.10. Calculated and experimental (FD-MS, cf. Chap. 8.5.4) isotopic pattern of a ruthenium carbonyl porphyrin complex. The isotopic pattern supports the presumed molecular composition. The label is attached to the peak corresponding to the ° Ru-contaming ion. Adapted fromRef. [17] with permission. IM Publications, 1997.

Frauenkron, M. Berkessel, A. Gross, J.H. Analysis of Ruthenium Carbonyl-Porphyrin Complexes a Comparison of Matrix-Assisted Laser Desorp-tion/Ionization Time-of-Flight, Fast-Atom Bombardment and Field Desorption Mass Spectrometry. Eur. Mass Spectrom. 1997, 5,427-438. 

Example The FD spectrum of a ruthenium-carbonyl-porphyrin complex shows an isotopic pattern very close to the theoretical distribution (Chap. 3.2.8). The loss of the carbonyl ligand chiefly results from thermal decomposition. A spectmm accumulated close to BAT (scans 19-25, EHC = 25-30 mA) is nearly free from CO loss while a spectrum accumulated of scans 30-36 (35 0 mA)... 

The iridium complex contained a tightly bound carbonyl group, unlike the rhodium complex, in accord with the stronger bonding of CO groups to 5d than to transition metals (216). Related iron and ruthenium carbonyl porphyrins have also been described 14, 217, 461). 

A very prominent class of metalloporphyrins are the tetra(aryl)porphyrin ruthenium carbonyl complexes [(Aryl)4Por)Ru(CO)(L)] (L = solvent) that, in... 

After initial characterization of the p-GaInP2 electrode material, seven different porphyrin treatments were evaluated for their ability to modify the surface of the p-GaInP2 electrode. All of the porphyrins show a statistically significant shift in flat band potential, with the ruthenated porphyrins showing the greatest shift. The bandedges shifted into overlap conditions about 20% of the time with ruthenium octaethyl porphyrin carbonyl RuOEP CO. The variability observed in the flat band potential was attributed to the porphyrin application method and/or the age of the electrode, both of which affect the amount of porphyrin on the p-GaInP2 surface. 

A two-electron oxidation of Ru(II)(TPFPP) (CO) would produce oxoRu(IV) porphyrin and eventually dioxoRufVT). What is the alternative pathway for Ru (TPFPP)(CO) activation It is known that ruthenium(II) ir-cation radicals are formed from the corresponding carbonyl compounds by chemical or electrochemical one-electron oxidation . Such species have been... 

Double bonded ruthenium and osmium homodimers have been synthesized by Coil-man . These two metals are inserted into the porphyrin free base by using the corresponding metal chlorocarbonyl dimer [MCl2(CO)3]2- Irradiation of the resulting carbonyl metal(II) porphyrin irradiated in pyridine solutions yields the bis(pyridine) metal(II) porphyrin and leads to the expected dimers by heating under vacuum. This is shown in Scheme 16. 

Recently, a novel porphyrin-based polymer, namely a poly(CO-Ru(n)-64) (with CO-Ru(n)-64 = ruthenium carbonyl spirobifluorenylporphyrin), was prepared electrochemically and used for the transfer of carbene to olefins and sulphides in a solid-state reaction. In another original study, a bimetallic porphyrin film using 65 was studied as electrode modifier with catalytic activity for molecular oxygen reduction and hydrogen peroxide reduction " . 

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