0000000000603029
AUTHOR
Maurice L'her
Dihydrogen complexes of metalloporphyrins: characterization and catalytic hydrogen oxidation activity
A series of monometallic dihydrogen complexes of the type M(OEP)(L)(H{sub 2}) (M = Ru, Os; L = THF, *Im) was synthesized and characterized by {sup 1}H NMR. The H-H bond length was found to increase when Os was replaced by Ru or when *Im was replaced by THF. The bond distances (as determined by T{sub 1}) range from 0.92 to 1.18 {angstrom}. The first example of a bimetallic bridging dihydrogen complex, Ru{sub 2}(DPB)(*IM){sub 2}(H{sub 2}), was also prepared. The H{sub 2} ligand is simultaneously bound to both Ru-metal centers. High-field {sup 1}H NMR experiments (620 MHz) revealed a -7.37 Hz dipolar splitting of the H{sub 2} ligand for this complex. Analysis of this splitting suggests that th…
Electrocatalytic reduction of dioxygen to water by tren-capped porphyrins, functional models of cytochrome c oxidase
International audience; Two different tren-capped porphyrins—in which the two metals, iron and copper, are more or less off-centered—are shown to be efficient catalysts for the reduction of O2 to H2O; surprisingly, their iron-only complexes are shown to be even more effective 4e- catalysts when adsorbed on a graphiteelectrode.