%0 Journal Article %1 Waldhoer.1997b %A Waldhoer, Eberhard %A Kaim, Wolfgang %A Olabe, Jose A. %A Slep, Leonardo D. %A Fiedler, Jan. %D 1997 %J Inorganic Chemistry %K IR analog;near complex complex;EPR complex;IR complex;iron complex;osmium complex;visible cyano electrochem metal methylpyrazinium nitrosyl pentacyano redn spectra spectroscopy;UV spectroscopy;electrochem spectroscopy;methylpyrazinium spectroscopy;ruthenium %N 14 %P 2969--2974 %R 10.1021/IC961426A %T The mpz+/mpz.bul. pair as organic analog of the NO+/NO.bul. ligand redox system (mpz = N-methylpyrazinium). A combined electrochemical and spectroscopic study (UV/Vis/NIR, IR, EPR) of complexes [(mpz)M(CN)5]2-/3- (M = Fe, Ru, Os) %V 36 %X The oxidn. and redn. behavior of [(mpz)M(CN)5]2- between the group 8 pentacyanometalates(II) and the N-methylpyrazinium ion mpz+ was studied using spectroelectrochem. techniques (UV/visible/NIR, IR, EPR) in nonaq. and, in part, aq. media. As a further source of information on the electronic structure, the authors studied the variable solvatochromism of MLCT absorption bands in the precursor ions [(mpz)M(CN)5]2-. The mpz-centered 1-electron redn. showed a tendency for concomitant loss of cyanide (EC process) to yield [(mpz)M(CN)4]2-, the lability increasing in the order M = Os \textless\textless Ru \textless Fe. In contrast to the EPR spectra obtained from redn. with S2O42- in aq. media, which showed no evidence for close mpz.bul./metal assocn., the intra muros electrolysis expts. in DMSO or acetonitrile yielded the following results: The EPR spectrum that was previously assigned to [(mpz)Fe(CN)5]3- is now ascribed to [(mpz)Fe(CN)4]2-. Whereas the dissociatively inert osmium radical complex [(mpz)Os(CN)5]3- is distinguished by a broad EPR signal with a rather large value giso = 2.0157, the EPR spectrum of [(mpz)Ru(CN)4]3- reveals well-resolved sep. coupling with the 99Ru and 101Ru isotopes in natural abundance. Spectroelectrochem. and reactivity patterns of [(mpz)M(CN)5]2- are reminiscent of results for corresponding nitrosyl complexes [(NO)M(CN)5]2-, which suggests that the mpz+/mpz.bul. ligand redox pair can function as an org. analog of the NO+/NO.bul. redox system. [on SciFinder(R)]

@article{Waldhoer.1997b, abstract = {The oxidn. and redn. behavior of [(mpz)M(CN)5]2- between the group 8 pentacyanometalates(II) and the N-methylpyrazinium ion mpz+ was studied using spectroelectrochem. techniques (UV/visible/NIR, IR, EPR) in nonaq. and, in part, aq. media. As a further source of information on the electronic structure, the authors studied the variable solvatochromism of MLCT absorption bands in the precursor ions [(mpz)M(CN)5]2-. The mpz-centered 1-electron redn. showed a tendency for concomitant loss of cyanide (EC process) to yield [(mpz)M(CN)4]2-, the lability increasing in the order M = Os {\textless}{\textless} Ru {\textless} Fe. In contrast to the EPR spectra obtained from redn. with S2O42- in aq. media, which showed no evidence for close mpz.bul./metal assocn., the intra muros electrolysis expts. in DMSO or acetonitrile yielded the following results: The EPR spectrum that was previously assigned to [(mpz)Fe(CN)5]3- is now ascribed to [(mpz)Fe(CN)4]2-. Whereas the dissociatively inert osmium radical complex [(mpz)Os(CN)5]3- is distinguished by a broad EPR signal with a rather large value giso = 2.0157, the EPR spectrum of [(mpz)Ru(CN)4]3- reveals well-resolved sep. coupling with the 99Ru and 101Ru isotopes in natural abundance. Spectroelectrochem. and reactivity patterns of [(mpz)M(CN)5]2- are reminiscent of results for corresponding nitrosyl complexes [(NO)M(CN)5]2-, which suggests that the mpz+/mpz.bul. ligand redox pair can function as an org. analog of the NO+/NO.bul. redox system. [on SciFinder(R)]}, added-at = {2019-07-15T13:41:23.000+0200}, author = {Waldhoer, Eberhard and Kaim, Wolfgang and Olabe, Jose A. and Slep, Leonardo D. and Fiedler, Jan.}, biburl = {https://puma.ub.uni-stuttgart.de/bibtex/2a83ace2d15ec7d1724d2428b9ea180ba/b_schwederski}, doi = {10.1021/IC961426A}, interhash = {f80277317110f749ff6a1ec2a77933fb}, intrahash = {a83ace2d15ec7d1724d2428b9ea180ba}, issn = {0020-1669}, journal = {Inorganic Chemistry}, keywords = {IR analog;near complex complex;EPR complex;IR complex;iron complex;osmium complex;visible cyano electrochem metal methylpyrazinium nitrosyl pentacyano redn spectra spectroscopy;UV spectroscopy;electrochem spectroscopy;methylpyrazinium spectroscopy;ruthenium}, number = 14, pages = {2969--2974}, timestamp = {2019-07-15T11:42:10.000+0200}, title = {The mpz+/mpz.bul. pair as organic analog of the NO+/NO.bul. ligand redox system (mpz = N-methylpyrazinium). A combined electrochemical and spectroscopic study (UV/Vis/NIR, IR, EPR) of complexes [(mpz)M(CN)5]2-/3- (M = Fe, Ru, Os)}, volume = 36, year = 1997 }