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A Ruthenium(III)–Oxyl Complex Bearing Strong Radical Character
Author(s) -
Shimoyama Yoshihiro,
Ishizuka Tomoya,
Kotani Hiroaki,
Shiota Yoshihito,
Yoshizawa Kazunari,
Mieda Kaoru,
Ogura Takashi,
Okajima Toshihiro,
Nozawa Shunsuke,
Kojima Takahiko
Publication year - 2016
Publication title -
angewandte chemie
Language(s) - English
Resource type - Journals
eISSN - 1521-3757
pISSN - 0044-8249
DOI - 10.1002/ange.201607861
Subject(s) - chemistry , ruthenium , reactivity (psychology) , carbene , benzoic acid , photochemistry , ligand (biochemistry) , benzaldehyde , oxidation state , catalysis , raman spectroscopy , medicinal chemistry , stereochemistry , organic chemistry , medicine , biochemistry , physics , alternative medicine , receptor , pathology , optics
Proton‐coupled electron‐transfer oxidation of a Ru II −OH 2 complex, having an N‐heterocyclic carbene ligand, gives a Ru III −O . species, which has an electronically equivalent structure of the Ru IV =O species, in an acidic aqueous solution. The Ru III −O . complex was characterized by spectroscopic methods and DFT calculations. The oxidation state of the Ru center was shown to be close to +3; the Ru−O bond showed a lower‐energy Raman scattering at 732 cm −1 and the Ru−O bond length was estimated to be 1.77(1) Å. The Ru III −O . complex exhibits high reactivity in substrate oxidation under catalytic conditions; particularly, benzaldehyde and the derivatives are oxidized to the corresponding benzoic acid through C−H abstraction from the formyl group by the Ru III −O . complex bearing a strong radical character as the active species.