%0 Journal Article %1 Ladwig.1991 %A Ladwig, Monika %A Kaim, Wolfgang. %D 1991 %J Journal of Organometallic Chemistry %K MO bidiazine bidiazinerhodium;rhodium catalyst electrochem extn hydrogen isomer redox water %N 1-2 %P 233--243 %R 10.1016/0022-328X(91)86178-S %T Spectroscopic and electrochemical properties of the isomeric bidiazine complexes (C5Me5)ClRh(bdz)+ and (C5Me5)Rh(bdz) and their relevance to the catalysis of the 2 H+ $\rightarrow$ H2 reaction by 2,2'-bipyridine analogs %V 419 %X Electronic structures and ligand effects were studied for the isomeric Rh(III/I) complexes (C5Me5)ClRh(bdz)(X) (X- = Cl-, PF6-; bdz = 3,3'-bipyridazine, 2,2'-bipyrazine, 2,2'- and 4,4'-bipyrimidine) and (C5Me5)Rh(bdz). Comparative NMR and UV-visible spectroscopic and cyclic-voltammetry measurements in aprotic solvents allowed definition of a frontier-MO situation that was correlated with the reactivity of the (C5Me5)ClRh(bpy)+ system as a catalyst for H evolution from H2O. Thus, while the potential for the 2-electron redn. of the Rh(III) halide precursor depends on the ligand basicity, the MO description shows that there is extremely strong p-back donation and orbital mixing between the d orbitals of the H+-accepting (C5Me5)Rh(I) fragment and the acceptor level of the heterocyclic ligand. on SciFinder(R)

@article{Ladwig.1991, abstract = {Electronic structures and ligand effects were studied for the isomeric Rh(III/I) complexes [(C5Me5)ClRh(bdz)](X) (X- = Cl-, PF6-; bdz = 3,3'-bipyridazine, 2,2'-bipyrazine, 2,2'- and 4,4'-bipyrimidine) and (C5Me5)Rh(bdz). Comparative NMR and UV-visible spectroscopic and cyclic-voltammetry measurements in aprotic solvents allowed definition of a frontier-MO situation that was correlated with the reactivity of the [(C5Me5)ClRh(bpy)]+ system as a catalyst for H evolution from H2O. Thus, while the potential for the 2-electron redn. of the Rh(III) halide precursor depends on the ligand basicity, the MO description shows that there is extremely strong \textgreek{p}-back donation and orbital mixing between the d orbitals of the H+-accepting (C5Me5)Rh(I) fragment and the acceptor level of the heterocyclic ligand. [on SciFinder(R)]}, added-at = {2022-06-15T11:26:56.000+0200}, author = {Ladwig, Monika and Kaim, Wolfgang.}, biburl = {https://puma.ub.uni-stuttgart.de/bibtex/2e7360ef339fe90b319c5d6d3e26505a7/huebleriac}, doi = {10.1016/0022-328X(91)86178-S}, interhash = {081b27b5376b1c39cf14460e67cbeed1}, intrahash = {e7360ef339fe90b319c5d6d3e26505a7}, journal = {Journal of Organometallic Chemistry}, keywords = {MO bidiazine bidiazinerhodium;rhodium catalyst electrochem extn hydrogen isomer redox water}, number = {1-2}, pages = {233--243}, timestamp = {2022-06-15T09:26:56.000+0200}, title = {Spectroscopic and electrochemical properties of the isomeric bidiazine complexes [(C5Me5)ClRh(bdz)]+ and (C5Me5)Rh(bdz) and their relevance to the catalysis of the 2 H+ $\rightarrow$ H2 reaction by 2,2'-bipyridine analogs}, volume = 419, year = 1991 }