%0 Journal Article %1 Heilmann.1999 %A Heilmann, Oliver %A Hornung, Fridmann M. %A Fiedler, Jan %A Kaim, Wolfgang. %D 1999 %J Journal of Organometallic Chemistry %K alloxazine complex complex;ESR complex;electrochem complex;iridium crystal cyclopentadienyl dimethylalloxazine electrochem iridium pivaloylpterin prepn redn redn;rhenium rhenium structure %N 1 %P 2--10 %R 10.1016/S0022-328X(99)00294-6 %T Organometallic iridium(III) and rhenium(I) complexes with lumazine, alloxazine and pterin derivatives %V 589 %X Two organometallic complex fragments with 5d6 configurated metal centers of different character, electrophilic IrIIICp*Cl+ and p-donating ReI(CO)3Cl, were used as probes in compds. contg. 1,3-dimethyllumazine (DML), 1,3-dimethylalloxazine (DMA), 2-pivaloylpterin (PP) and 6-methyl-2-pivaloylpterin (MPP) as biochem. relevant ligands. Evidence from spectroscopy (NMR, IR, UV-visible) in aprotic solvents points in most cases to the O4 and N5 atoms as chelate donors for metal binding. For (DMA)IrIIICp*Cl(PF6) this was substantiated by a crystal structure anal. With PP, however, an Ir(III) compd. with pivaloyl-coordinated metal was obtained. Whereas both the IrIII and Re1 complexes of the good p acceptor ligand DMA can be reduced reversibly and thus studied by (spectro)electrochem. (IR, UV-visible, EPR: ligand-centered 1-electron redn.), the DML system exhibits such behavior only for the IrIII species. The complexes of the 2-pivaloylpterins showed only irreversible redn. on SciFinder(R)

@article{Heilmann.1999, abstract = {Two organometallic complex fragments with 5d6 configurated metal centers of different character, electrophilic [IrIIICp*Cl]+ and \textgreek{p}-donating [ReI(CO)3Cl], were used as probes in compds. contg. 1,3-dimethyllumazine (DML), 1,3-dimethylalloxazine (DMA), 2-pivaloylpterin (PP) and 6-methyl-2-pivaloylpterin (MPP) as biochem. relevant ligands. Evidence from spectroscopy (NMR, IR, UV-visible) in aprotic solvents points in most cases to the O4 and N5 atoms as chelate donors for metal binding. For [(DMA)IrIIICp*Cl](PF6) this was substantiated by a crystal structure anal. With PP, however, an Ir(III) compd. with pivaloyl-coordinated metal was obtained. Whereas both the IrIII and Re1 complexes of the good \textgreek{p} acceptor ligand DMA can be reduced reversibly and thus studied by (spectro)electrochem. (IR, UV-visible, EPR: ligand-centered 1-electron redn.), the DML system exhibits such behavior only for the IrIII species. The complexes of the 2-pivaloylpterins showed only irreversible redn. [on SciFinder(R)]}, added-at = {2022-06-15T11:26:56.000+0200}, author = {Heilmann, Oliver and Hornung, Fridmann M. and Fiedler, Jan and Kaim, Wolfgang.}, biburl = {https://puma.ub.uni-stuttgart.de/bibtex/26807a392619458788a19f14c521e2e35/huebleriac}, doi = {10.1016/S0022-328X(99)00294-6}, interhash = {65d2f2f928547de68a075e47fbc512dc}, intrahash = {6807a392619458788a19f14c521e2e35}, journal = {Journal of Organometallic Chemistry}, keywords = {alloxazine complex complex;ESR complex;electrochem complex;iridium crystal cyclopentadienyl dimethylalloxazine electrochem iridium pivaloylpterin prepn redn redn;rhenium rhenium structure}, number = 1, pages = {2--10}, timestamp = {2022-06-15T09:26:56.000+0200}, title = {Organometallic iridium(III) and rhenium(I) complexes with lumazine, alloxazine and pterin derivatives}, volume = 589, year = 1999 }