TY - JOUR
T1 - Multi-Electron Oxidation of Anthracene Derivatives by Nonheme Manganese(IV)-Oxo Complexes
AU - Sharma, Namita
AU - Jung, Jieun
AU - Lee, Yong Min
AU - Seo, Mi Sook
AU - Nam, Wonwoo
AU - Fukuzumi, Shunichi
N1 - Funding Information:
This work was supported by a SENTAN project from Japan Science and Technology Agency (JST) to S.F. and JSPS KAKENHI (No. 16HO2268 to S.F.) from MEXT Japan, and NRF of Korea through the CRI (NRF-2012R1A3A2048842) and GRL (NRF-2010-00353) program to W.N.
Publisher Copyright:
© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
PY - 2017/5/23
Y1 - 2017/5/23
N2 - Six-electron oxidation of anthracene to anthraquinone by a nonheme MnIV-oxo complex, [(Bn-TPEN)MnIV(O)]2+, proceeds through a rate-determining electron transfer from anthracene to [(Bn-TPEN)MnIV(O)]2+, followed by subsequent fast oxidation reactions to give anthraquinone. The reduced MnII complex ([(Bn-TPEN)MnII]2+) is oxidized by [(Bn-TPEN)MnIV(O)]2+ rapidly to produce the μ-oxo dimer ([(Bn-TPEN)MnIII-O-MnIII(Bn-TPEN)]4+). The oxygen atoms of the anthraquinone product were found to derive from the manganese-oxo species by the 18O-labelling experiments. In the presence of Sc3+ ion, formation of an anthracene radical cation was directly detected in the electron transfer from anthracene to a Sc3+ ion-bound MnIV(O) complex, [(Bn-TPEN)MnIV(O)-(Sc(OTf)3)2]2+, followed by subsequent further oxidation to yield anthraquinone. When anthracene was replaced by 9,10-dimethylanthracene, electron transfer from 9,10-dimethylanthracene to [(Bn-TPEN)MnIV(O)-(Sc(OTf)3)2]2+ occurred rapidly to produce stable 9,10-dimethylanthracene radical cation. The driving force dependence of the rate constants of electron transfer from the anthracene derivatives to [(Bn-TPEN)MnIV(O)]2+ and [(Bn-TPEN)MnIV(O)-(Sc(OTf)3)2]2+ was well-evaluated in light of the Marcus theory of electron transfer.
AB - Six-electron oxidation of anthracene to anthraquinone by a nonheme MnIV-oxo complex, [(Bn-TPEN)MnIV(O)]2+, proceeds through a rate-determining electron transfer from anthracene to [(Bn-TPEN)MnIV(O)]2+, followed by subsequent fast oxidation reactions to give anthraquinone. The reduced MnII complex ([(Bn-TPEN)MnII]2+) is oxidized by [(Bn-TPEN)MnIV(O)]2+ rapidly to produce the μ-oxo dimer ([(Bn-TPEN)MnIII-O-MnIII(Bn-TPEN)]4+). The oxygen atoms of the anthraquinone product were found to derive from the manganese-oxo species by the 18O-labelling experiments. In the presence of Sc3+ ion, formation of an anthracene radical cation was directly detected in the electron transfer from anthracene to a Sc3+ ion-bound MnIV(O) complex, [(Bn-TPEN)MnIV(O)-(Sc(OTf)3)2]2+, followed by subsequent further oxidation to yield anthraquinone. When anthracene was replaced by 9,10-dimethylanthracene, electron transfer from 9,10-dimethylanthracene to [(Bn-TPEN)MnIV(O)-(Sc(OTf)3)2]2+ occurred rapidly to produce stable 9,10-dimethylanthracene radical cation. The driving force dependence of the rate constants of electron transfer from the anthracene derivatives to [(Bn-TPEN)MnIV(O)]2+ and [(Bn-TPEN)MnIV(O)-(Sc(OTf)3)2]2+ was well-evaluated in light of the Marcus theory of electron transfer.
KW - anthracene
KW - bioinorganic chemistry
KW - electron transfer
KW - hydrogen-atom transfer
KW - manganese
UR - http://www.scopus.com/inward/record.url?scp=85018959807&partnerID=8YFLogxK
U2 - 10.1002/chem.201700666
DO - 10.1002/chem.201700666
M3 - Article
C2 - 28345242
AN - SCOPUS:85018959807
SN - 0947-6539
VL - 23
SP - 7125
EP - 7131
JO - Chemistry - A European Journal
JF - Chemistry - A European Journal
IS - 29
ER -