Synthesis and redox properties of a meso-tris(4-nitrophenyl) corrolato Mn(III) complex
2005 (English)In: Journal of Porphyrins and Phthalocyanines, ISSN 1088-4246, E-ISSN 1099-1409, Vol. 9, no 6, 379-386 p.Article in journal (Refereed) Published
The Mn complexated corrole [T(4-NO2P)Corr]Mn(py) (3) has been prepared (py = pyridine) where [T(4-NO2P)Corr] is the trianion of the electron-poor 5,10,15-tris(4-nitrophenyl)-corrole (1). The preparation of 3 includes a new synthetic method to form the corrole ligand 1 in a two-step synthesis. The Mn(III) complex gives a parallel mode EPR signal centered around g = 8.2 with six distinct hyperfine lines (A(parallel to) = 139 x 10(-4) cm(-1)). Electrochemically 3 undergoes one reversible oxidation (E-1/2 = 0.12 V vs Fc) and two reversible reductions (E-1/2 = -1.45, -1.61 V). The oxidation is metal-centered and the product has been characterized by EPR spectroscopy as an S = 3/2 Mn(IV) species with no indication for oxidation of the macrocycle. The reductions of complex 3 are ligand based, and at the potential of the second reduction step a stable nitrogen centered radical with g = 2.0055 is generated. Chemical oxidation of 3 by iodosobenzene yields a Mn(IV) complex and epoxidation of cis-stilbene is not catalyzed by the Mn complex.
Place, publisher, year, edition, pages
2005. Vol. 9, no 6, 379-386 p.
manganese, corrole, valence tautomerization, electrochemistry, EPR spectroscopy, transition-metal centers, high-spin manganese(iii), dual-mode epr, high-frequency, iron corroles, structural-characterization, noninnocent ligands, porphyrin complexes, oxidation-states, spectroscopy
IdentifiersURN: urn:nbn:se:kth:diva-14970ISI: 000231126000001ScopusID: 2-s2.0-23644445640OAI: oai:DiVA.org:kth-14970DiVA: diva2:333011
QC 201005252010-08-052010-08-05Bibliographically approved