Research output: Contribution to journal › Article › peer-review
Highly Efficient Aromatic C-H Oxidation with H2O2 in the Presence of Iron Complexes of the PDP Family. / Tkachenko, Nikolay V.; Ottenbacher, Roman V.; Lyakin, Oleg Y. et al.
In: ChemCatChem, Vol. 10, No. 18, 20.09.2018, p. 4052-4057.Research output: Contribution to journal › Article › peer-review
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TY - JOUR
T1 - Highly Efficient Aromatic C-H Oxidation with H2O2 in the Presence of Iron Complexes of the PDP Family
AU - Tkachenko, Nikolay V.
AU - Ottenbacher, Roman V.
AU - Lyakin, Oleg Y.
AU - Zima, Alexandra M.
AU - Samsonenko, Denis G.
AU - Talsi, Evgenii P.
AU - Bryliakov, Konstantin P.
PY - 2018/9/20
Y1 - 2018/9/20
N2 - The catalytic activity of a series of iron complexes of the PDP family (PDP=N,N'-bis(2-pyridylmethyl)-2,2'-bipyrrolidine) in the oxidation of aromatic substrates with H2O2 has been studied. In the presence of acetic acid, these complexes efficiently catalyze the oxidation of benzene and alkylbenzenes with high selectivity for oxygen incorporation into the aromatic ring (up to 93%), performing up to 84 catalytic turnovers. The parent complex, [(PDP)(OTf)2], has demonstrated the highest catalytic efficiency and aromatic oxidation selectivity. The yield of products of oxidation of different substrates increases in line with increasing number of electron-donating alkyl groups of the substrates: halogenbenzenesH/kD (0.90-0.92), agrees with the SEAr oxidation mechanism. Low-temperature EPR studies have witnessed the presence of low-spin (g1=2.071, g2=2.008, g3=1.960) perferryl intermediates, demonstrating direct reactivity toward benzene. The oxidation of m-xylene in the presence of H2 18O has shown the same probability of 18O incorporation into the aromatic ring and the aliphatic moieties, which is indicative that both the aromatic and aliphatic oxidations are conducted by the same active species.
AB - The catalytic activity of a series of iron complexes of the PDP family (PDP=N,N'-bis(2-pyridylmethyl)-2,2'-bipyrrolidine) in the oxidation of aromatic substrates with H2O2 has been studied. In the presence of acetic acid, these complexes efficiently catalyze the oxidation of benzene and alkylbenzenes with high selectivity for oxygen incorporation into the aromatic ring (up to 93%), performing up to 84 catalytic turnovers. The parent complex, [(PDP)(OTf)2], has demonstrated the highest catalytic efficiency and aromatic oxidation selectivity. The yield of products of oxidation of different substrates increases in line with increasing number of electron-donating alkyl groups of the substrates: halogenbenzenesH/kD (0.90-0.92), agrees with the SEAr oxidation mechanism. Low-temperature EPR studies have witnessed the presence of low-spin (g1=2.071, g2=2.008, g3=1.960) perferryl intermediates, demonstrating direct reactivity toward benzene. The oxidation of m-xylene in the presence of H2 18O has shown the same probability of 18O incorporation into the aromatic ring and the aliphatic moieties, which is indicative that both the aromatic and aliphatic oxidations are conducted by the same active species.
KW - Aromatic substitution
KW - Hydrogen peroxide
KW - Intermediates
KW - Iron
KW - Oxidation
KW - NONHEME IRON
KW - CATALYZED HYDROCARBON OXIDATIONS
KW - ACTIVATION
KW - BENZENE
KW - MECHANISM
KW - hydrogen peroxide
KW - oxidation
KW - REACTIVITY
KW - TOLUENE
KW - intermediates
KW - MODELS
KW - iron
KW - HYDROGEN-PEROXIDE
KW - DIRECT HYDROXYLATION
UR - http://www.scopus.com/inward/record.url?scp=85049933145&partnerID=8YFLogxK
UR - https://www.mendeley.com/catalogue/18d674f7-ee38-3e68-a68a-8478cdd6e1a4/
U2 - 10.1002/cctc.201800832
DO - 10.1002/cctc.201800832
M3 - Article
AN - SCOPUS:85049933145
VL - 10
SP - 4052
EP - 4057
JO - ChemCatChem
JF - ChemCatChem
SN - 1867-3880
IS - 18
ER -
ID: 15962212