The
A mononuclear nonheme manganese(IV)–oxo complex binding the Ce4+ion, [(dpaq)MnIV(O)]+–Ce4+(
- Award ID(s):
- 1900476
- NSF-PAR ID:
- 10118060
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Angewandte Chemie International Edition
- Volume:
- 58
- Issue:
- 45
- ISSN:
- 1433-7851
- Page Range / eLocation ID:
- p. 16124-16129
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract syn andanti isomers of [FeIV(O)(TMC)]2+(TMC=tetramethylcyclam) represent the first isolated pair of synthetic non‐heme oxoiron(IV) complexes with identical ligand topology, differing only in the position of the oxo unit bound to the iron center. Both isomers have previously been characterized. Reported here is that thesyn isomer [FeIV(Osyn )(TMC)(NCMe)]2+(2 ) converts into itsanti form [FeIV(Oanti )(TMC)(NCMe)]2+(1 ) in MeCN, an isomerization facilitated by water and monitored most readily by1H NMR and Raman spectroscopy. Indeed, when H218O is introduced to2 , the nascent1 becomes18O‐labeled. These results provide compelling evidence for a mechanism involving direct binding of a water moleculetrans to the oxo atom in2 with subsequent oxo–hydroxo tautomerism for its incorporation as the oxo atom of1 . The nonplanar nature of the TMC supporting ligand makes this isomerization an irreversible transformation, unlike for their planar heme counterparts. -
Abstract The
syn andanti isomers of [FeIV(O)(TMC)]2+(TMC=tetramethylcyclam) represent the first isolated pair of synthetic non‐heme oxoiron(IV) complexes with identical ligand topology, differing only in the position of the oxo unit bound to the iron center. Both isomers have previously been characterized. Reported here is that thesyn isomer [FeIV(Osyn )(TMC)(NCMe)]2+(2 ) converts into itsanti form [FeIV(Oanti )(TMC)(NCMe)]2+(1 ) in MeCN, an isomerization facilitated by water and monitored most readily by1H NMR and Raman spectroscopy. Indeed, when H218O is introduced to2 , the nascent1 becomes18O‐labeled. These results provide compelling evidence for a mechanism involving direct binding of a water moleculetrans to the oxo atom in2 with subsequent oxo–hydroxo tautomerism for its incorporation as the oxo atom of1 . The nonplanar nature of the TMC supporting ligand makes this isomerization an irreversible transformation, unlike for their planar heme counterparts. -
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Abstract We report the single crystal XRD and MicroED structure, magnetic susceptibility, and EPR data of a series of CaMn3IVO4and YMn3IVO4complexes as structural and spectroscopic models of the cuboidal subunit of the oxygen‐evolving complex (OEC). The effect of changes in heterometal identity, cluster geometry, and bridging oxo protonation on the spin‐state structure was investigated. In contrast to previous computational models, we show that the spin ground state of CaMn3IVO4complexes and variants with protonated oxo moieties need not be
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