Stable NiII Porphyrin meso-Oxy Radical with a Quartet Ground State

Cosima Stähler; Daiki Shimizu; Kota Yoshida; Ko Furukawa; Rainer Herges; Atsuhiro Osuka

doi:10.1002/chem.201701354

Stable Ni^II Porphyrin meso-Oxy Radical with a Quartet Ground State

Chemistry. 2017 May 29;23(30):7217-7220. doi: 10.1002/chem.201701354. Epub 2017 May 2.

Authors

Cosima Stähler¹, Daiki Shimizu², Kota Yoshida², Ko Furukawa³, Rainer Herges¹, Atsuhiro Osuka²

Affiliations

¹ Otto-Diels-Institut für Organische Chemie, Christian-Albrechts-Universität zu Kiel, Otto-Hahn-Platz 4, Kiel, 24098, Germany.
² Department of Chemistry, Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto, 606-8502, Japan.
³ Center for Instrumental Analysis, Institute for Research Promotion, Niigata University, Nishi-ku, Niigata, 950-2181, Japan.

PMID: 28402012
DOI: 10.1002/chem.201701354

Abstract

10,15,20-Tris(pentafluorophenyl)-substituted Ni^II -porphyrin meso-oxy radical bearing two coordinating pyridines was synthesized as a stable radical with a quartet ground state (S=3/2). X-ray structural analysis revealed that the Ni^II porphyrin moiety is fairly planar and the Ni-N bond lengths are considerably longer, indicating the high-spin state of the Ni^II center. The radical exhibited a quartet ground state, indicating the ferromagnetic interaction between the high-spin Ni^II center (S=1) and the porphyrin meso-oxy radical (S=1/2).

Keywords: magnetism; nickel; porphyrins; spin crossover; stable radicals.