Construction of a square-planar hydroperoxo-copper(ii) complex inducing a higher catalytic reactivity

Fujii, Tatsuya; Naito, Asako; Yamaguchi, Syuhei; Wada, Akira; Funahashi, Yasuhiro; Jitsukawa, Koichiro; Nagatomo, Shigenori; Kitagawa, Teizo; Masuda, Hideki

doi:10.1039/b308073k

Cited by 76 publications

(86 citation statements)

References 17 publications

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“…The band at λ max = 380 nm (ε 1400 M −1 cm −1 ) is assignable to a − OOH –> Cu II LMCT absorption based on the correspondence with a number of literature examples 27,33-37. An axial Cu II EPR spectrum is also observed for 2 , consistent with a single mononuclear species formulation, but which is distinguishable from 1 (Figure 3b).…”

Section: Resultssupporting

confidence: 58%

Copper−Hydroperoxo-Mediated N-Debenzylation Chemistry Mimicking Aspects of Copper Monooxygenases

Sarjeant

Karlin

2008

Inorg. Chem.

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Substantial oxidative N-debenzylation reaction along with PhCH=O formation occurs from a hydroperoxo copper(II) complex which has a dibenzylamino substrate (-N(CH 2 Ph) 2 appended as a substituent on one pyridyl group of its tripodal tetradentate TMPA {≡ TPA ≡ tris(2-pyridylmethyl) amine)} ligand framework. During the course of the (L N(CH 2 Ph) 2 )Cu II ( − OOH) reactivity, formation of a substrate and − OOH (an oxygen atom) derived alkoxo Cu II ( − OR) complex occurs. The observation that the same Cu II ( − OR) species occurs from Cu I /PhIO chemistry suggests the possibility that a copper-oxo (cupryl) reactive intermediate forms during alkoxo species formation, and new ESI-MS data obtained provides some further support for this high-valent intermediate. Net H-atom abstraction chemistry is proposed, based on kinetic isotope effect studies provided here and that previously published for a closely related Cu II ( − OOH) species incorporating dimethylamine (-N (CH 3 ) 2 ) as the internal substrate (J. Am. Chem. Soc. 2007, 129, 6720-6721); the Cu I /PhIO reactivity, with similar isotope effect results, provides further support. The reactivity of these chemical systems closely resembles proposed oxidative N-dealkylation mechanisms effected by the coppermonooxygenases dopamine β-monooxygenase (DβM) or peptidylglycine-α-hydroxylating monooxygenase (PHM).

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Section: Resultssupporting

confidence: 58%

Copper−Hydroperoxo-Mediated N-Debenzylation Chemistry Mimicking Aspects of Copper Monooxygenases

Sarjeant

Karlin

2008

Inorg. Chem.

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“…The EPR spectrum revealed an anisotropic signal with g k ¼ 2.26, g t ¼ 2.07 and g av ¼ 2.13 computed from the expression g av 2 ¼ (g k 2 þ2g t 2 )/3, was observed. The trend g k > g t > 2.0023 revealed that the unpaired electron most likely localized in d x 2 À y 2 orbital consistent with the square planar geometry [16].…”

Section: Spectroscopymentioning

confidence: 72%

Synthesis and crystal structure determination of copper(II)-complex: In vitro DNA and HSA binding, pBR322 plasmid cleavage, cell imaging and cytotoxic studies

Tabassum

Zaki

Ahmad

et al. 2014

European Journal of Medicinal Chemistry

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“…Building upon previous work focused primarily on the characterization of monocopper-hydroperoxo and -alkylperoxo complexes [299][300][301][302][303][304], more recent research has emphasized reactivity studies. For example, the complexes 87a, b ( Figure 43) decompose to yield mixtures of products resulting from oxidation of substituents R (e.g., N-alkylation, formation of aldehydes or ketones) [299,305].…”

Section: Cuoor Complexesmentioning

confidence: 99%

Transition Metal Complexes and the Activation of Dioxygen

Yee

Tolman

2014

Metal Ions in Life Sciences

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In order to address how diverse metalloprotein active sites, in particular those containing iron and copper, guide O₂binding and activation processes to perform diverse functions, studies of synthetic models of the active sites have been performed. These studies have led to deep, fundamental chemical insights into how O₂coordinates to mono- and multinuclear Fe and Cu centers and is reduced to superoxo, peroxo, hydroperoxo, and, after O-O bond scission, oxo species relevant to proposed intermediates in catalysis. Recent advances in understanding the various factors that influence the course of O₂activation by Fe and Cu complexes are surveyed, with an emphasis on evaluating the structure, bonding, and reactivity of intermediates involved. The discussion is guided by an overarching mechanistic paradigm, with differences in detail due to the involvement of disparate metal ions, nuclearities, geometries, and supporting ligands providing a rich tapestry of reaction pathways by which O₂is activated at Fe and Cu sites.

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Construction of a square-planar hydroperoxo-copper(ii) complex inducing a higher catalytic reactivity

Abstract: A novel hydroperoxo-copper(II) complex with a square-planar geometry has been prepared, which has exhibited a higher selectivity and catalytic reactivity for dimethyl sulfide, in contrast to that with a trigonal-bipyramidal one.

Cited by 76 publications

References 17 publications

Copper−Hydroperoxo-Mediated N-Debenzylation Chemistry Mimicking Aspects of Copper Monooxygenases

Copper−Hydroperoxo-Mediated N-Debenzylation Chemistry Mimicking Aspects of Copper Monooxygenases

Synthesis and crystal structure determination of copper(II)-complex: In vitro DNA and HSA binding, pBR322 plasmid cleavage, cell imaging and cytotoxic studies

Transition Metal Complexes and the Activation of Dioxygen

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