Bioinspired Oxidative Cleavage of Aliphatic C–C Bonds Utilizing Aerial Oxygen by Nickel Acireductone Dioxygenase Mimics

Article abstract of DOI:10.1002/ejic.201801471

Bioinspired oxidative cleavage of aliphatic C–C bonds of the acireductone model substrate 2-hydroxy-3-oxo-1,3-diphenylprop-1-en-1-olate, bound to two paramagnetic nickel(II) complexes that are mimics for the nickel containing acireductone dioxygenase, has been achieved utilizing aerial oxygen under ambient conditions.

Full text of DOI:10.1002/ejic.201801471

A Journal of
Accepted Article
Title: Bioinspired Oxidative Cleavage of Aliphatic C-C Bond Utilizing
Aerial Oxygen by Nickel Acireductone Dioxygenase Mimics
Authors: Sakthi Raje, Kalaikodikumaran Mani, Parameswaran
Kandasamy, Ray J Butcher, and Raja Angamuthu
This manuscript has been accepted after peer review and appears as an
Accepted Article online prior to editing, proofing, and formal publication
of the final Version of Record (VoR). This work is currently citable by
using the Digital Object Identifier (DOI) given below. The VoR will be
published online in Early View as soon as possible and may be different
to this Accepted Article as a result of editing. Readers should obtain
the VoR from the journal website shown below when it is published
to ensure accuracy of information. The authors are responsible for the
content of this Accepted Article.
To be cited as: Eur. J. Inorg. Chem. 10.1002/ejic.201801471
Link to VoR: http://dx.doi.org/10.1002/ejic.201801471

10.1002/ejic.201801471
European Journal of Inorganic Chemistry
Communication
Communication
N
N
N
distorted octahedral geometry around Ni(II) ion (Fig. 4); the
distortion is enforced by the tetradentate N4 ligand that folded to
coordinate two basal and two apical coordination sites leaving two
adjacent positions for labile ligands.
N
N
N
N
N
N
N
N
N
N
Bioinspired Oxidative Cleavage of Aliphatic C-C Bond Utilizing
Aerial Oxygen by Nickel Acireductone Dioxygenase Mimics
Sakthi Raje,[a][‡] Kalaikodikumaran Mani,[a][‡] Parameswaran Kandasamy,[a] Ray J. Butcher,[b]
Raja Angamuthu*[a]
Ph
Ph
Ph
6-Ph2TPA
6-PhTPA
BBP
The green suspensions of [Ni(L1)Cl2] or [Ni(L2)Cl2] in
acetonitrile was mixed and stirred with 2.2 equivalents of NaBPh4
Figure 2. The ligands used by Berreau (6-Ph2TPA, 6-PhTPA)[35-44] and
Mayilmurugan (BBP)[45] to mimic the active site of Ni-ARD.
to
obtain
purple
color
[Ni(L1)(CH3CN)2](BPh4)2
or
[Ni(L2)(CH3CN)2](BPh4)2; the ESI-MS envelopes observed at m/z
239.0821 and 205.0904 that correspond to [Ni(L1)]2+ (calcd. m/z
= 239.0833) and [Ni(L2)]2+ (calcd. m/z = 205.0990) confirmed the
anion exchange (Fig. S7-S10). The solid-state structure of the
purple crystals of the later exhibited the molecular composition as
[Ni(L2)(CH3CN)2](BPh4)2×CH3CN, which was used in further
studies.
The first report of Berreau described the aliphatic carbon-
carbon bond cleavage reactivity of
a Ni(II) cis-b-keto-enolate
complex, [(6-Ph2TPA)Ni(A2)]ClO4 (Fig. 2, 3) in the presence of
two equivalents of base and oxygen; [(6-Ph2TPA)Ni(A2)]+ reacted
with O2 to produce [(6-Ph2TPA)Ni(OOCPh)2(H2O)] and CO.[35]
Though the model substrate A2 that is closely relevant to aci-
reductone underwent C-C cleavage, substrates such as A1, A3
and A4 were unreactive towards dioxygen; the complexes [(6-
Ph2TPA)Ni(A3)]ClO4 and [(6-Ph2TPA)Ni(A1)]ClO4 were found to
be unreactive towards dioxygen (Fig. 2, 3).[36] In contradiction,
[Ni(BBP)(A3)(H2O)Cl2] is shown to be reactive towards
dioxygen;[45] BBP is a linear tridentate ligand while all the models
reported by Berreau possessed tris-picolylamine based tripodal
tetradentate ligands such as 6-Ph2TPA[35-43] and 6-PhTPA[44] (Fig.
2).
In our view, Mayilmurugan’s model is closer to the resting
state of Ni-ARD as it possesses N3O3 donor set while all the
successful functional mimics of Berreau have N4O2 donor sets.
Hence one might wonder if subtle changes in the N4 ligand
system would still yield working models or not. To test this, we
have chosen the macrocyclic N4 tetradentate ligands L1 and L2
(Fig. 3).
Abstract: Bioinspired oxidative cleavage of aliphatic C-C bonds of
acireductone model substrate, 2-hydroxy-3-oxo-1,3-diphenylprop-1-
en-1-olate, bound to two paramagnetic nickel(II) complexes that are
mimics for the nickel containing acireductone dioxygenase has been
achieved utilizing aerial oxygen under ambient conditions.
The ARD is known since 1993 as part of the study of the
methionine salvage pathway in Klebsiella pneumoniae;[31] it was
found to cleave the key intermediate of this pathway, aci-
reductone and its analogues.[32,33] Investigations using K.
pneumoniae revealed that acireductone is oxidized to two
different sets of products. A dioxygenase activity produces the a-
ketoacid precursor of methionine and formic acid in the productive
case;[29,32] in a second, non-productive case, the aci-reductone is
Introduction
converted
into
formate,
carbon
monoxide,
and
methylthiopropionic acid. Curiously, both activities stem from the
same protein (ARD), but result from the differences in metal
content. Further investigations using recombinant protein
confirmed that iron-containing ARD (Fe-ARD) is responsible for
the productive activity and the non-productive activity is from the
Ni– or Co–containing ARD (Ni-ARD or Co-ARD).[32] The overall
structure of ARD was elucidated employing high-resolution NMR
spectroscopy,[28,30] while the active site structure was studied
using X-ray crystallography in recent years.[34] The active site
found in mammalian ARD appears to possess an octahedral
geometry with three oxygen donors provided by Glu94 and two
water molecules in addition to three nitrogen donors provided by
His88, His90 and His133 (Fig. 1); each histidine is trans located
to an oxygen donor at the paramagnetic nickel(II) ion.[34]
Nickel-containing enzymes assist the catalysis of many important
biological processes. Most of them are significant in the context
of industry and environment, such as (1) hydrolysis of urea to
ammonia (urease),[1-4] (2) interconversion of carbon monoxide
and carbon dioxide (carbon monoxide dehydrogenase), (3) acetyl
group metabolism into separate one-carbon units or acetate
synthesis using one-carbon precursors (acetyl-coenzyme
A
synthase),[5-13] (4) isomerization of hemithioacetal in order to
detoxify the cytotoxic methylglyoxal (glyoxalase I),[14-16] (5)
reversible interconversion of dihydrogen into protons and
electrons (NiFe hydrogenase),[17-21] (6) degradation of
methylenediurea, a slow release fertilizer (methylenediurease),[22]
(7) methane generation (methyl-coenzyme M reductase),[23] (8)
dismutation of toxic and cell damaging superoxide radical anions
tBu
Bn
N
N
R''
N
N
N
N
A1:
R' A2:
A3:
R' = Me; R'' = H
R' = Ph; R" = OH
R' = Ph; R'' = H
R' = Ph; R'' = Cl
R'
Figure
4.
Solid-state
structures
of
[Ni(L1)Cl2]×H2O
(left)
and
[Ni(L2)(CH3CN)2](BPh4)2×CH3CN (right). Solvents, counter anions and
hydrogens are omitted for sake of clarity. Selected bond distances [Å] of
[Ni(L1)Cl2]: Ni-N(2), 2.013(3); Ni-N(4), 2.023(3); Ni-N(1), 2.219(3); Ni-N(3),
2.228(3); Ni-Cl(1), 2.3908(10); Ni-Cl(2), 2.4584(9). Selected bond distances [Å]
of [Ni(L2)(CH3CN)2](BPh4)2: Ni-N(3), 1.972(5); Ni-N(1), 1.982(5); Ni-N(6),
2.055(6); Ni-N(5), 2.076(6); Ni-N(2), 2.268(5); Ni-N(4), 2.280(5). More details
are provided as supporting information (Figures S1, S2; Tables S1, S2).
A4:
O
O
N
N
tBu
Bn
A1-A4
L1
L2
into
dismutase)[24,25] and on top of all, (9) oxidation of 1,2-dihydroxy-3-
keto-5-methylthiopentene (aci-reductone) into methylthio
harmless
molecular
oxygen
(nickel
superoxide
Figure 3. Pyridinophane macrocyclic ligands (L1 and L2) and aci-reductone
model substrates (A1-A4) chosen for the present study.
R''
propionic acid, formic acid and carbon monoxide (acireductone
dioxygenase, ARD; Scheme 1).[26-30]
Here we report two new Ni(II) complexes of macrocyclic N4
tetradentate ligands, their adducts with substrates A1-A4 and the
reactivity of the adducts towards aerial oxygen (Fig. 3). The
complexes and adducts are characterized using NMR
spectroscopy, ESI-Mass spectrometry and X-ray crystallographic
techniques appropriately.
R'
R'
2+
+
tBu
tBu
O
O
N
N
O
OH
Fe
Ni/Co
N
N
N
N
R'
COOH
NCCH3
+
OH
O2
S
O
S
COOH
S
Me4NOH
R''
+
OH
+
Ni
Ni
O
+
HCOOH CO
HCOOH
Aci-reductone
R'
NCCH3
N
N
tBu
tBu
Scheme 1. Metal dependent reactions catalyzed by ARD.
Scheme 2. Synthesis of mimics of enzyme-substrate adducts.
Results and Discussion
Figure 1. Solid-state structure of the active site of ARD found in Mus musculus
(Ni-MmARD) with Ni(II) ion (extracted from pdb 5I91).[34]
Equimolar mixtures of [Ni(L1)(CH3CN)2](BPh4)2 or
[Ni(L2)(CH3CN)2](BPh4)2, protonated precursors of adducts (HA1-
HA4) and tetramethylammonium hydroxide yielded the mimics of
enzyme-substrate adducts [Ni(L1)(A1-A4)](BPh4) or [Ni(L2)(A1-
A4)](BPh4) in good yields. The ESI-MS envelopes indicated the
formation of the adducts (Fig. S11-S16); the SCXRD analyses of
[Ni(L2)(A1)](BPh4), [Ni(L2)(A3)](BPh4) and [Ni(L2)(A4)](BPh4)
exhibited the molecular structure of the adducts (Fig. 5). In all the
The straight forward reactions of NiCl2×6H2O and L1 or L2
yielded [Ni(L1)Cl2] and [Ni(L2)Cl2] in good yields. Preliminary
analysis using high resolution electrospray ionization mass
spectrometry (ESI-MS) confirmed the formation of [Ni(L1)Cl2]
(calcd. m/z for [Ni(L1)Cl]+ is 513.1356 and observed m/z is
513.1355; Fig. S3, S4) and [Ni(L2)Cl2] (calcd. m/z for [Ni(L2)Cl]+
is 445.1669 and observed m/z is 445.1642; Fig. S5, S6).
[a]
S. Raje, K. Mani, P. Kandasamy, Prof. R. Angamuthu,
A limited number of structural and functional models have
been reported since 2004 in an effort to understand the catalytic
mechanism of ARD by Berreau[35-44] and Mayilmurugan.[45]
Berreau employed the paramagnetic Ni(II) complexes of 6-
Ph2TPA[35-43] and 6-PhTPA[44] as mimics of Ni-ARD while
Mayilmurugan used [Ni(BBP)(H2O)Cl2][45] as the starting point.
Laboratory of Inorganic Synthesis and Bioinspired Catalysis
(LISBIC)
Department of Chemistry
Indian Institute of Technology Kanpur
Kanpur 208016, India
E-mail: raja@iitk.ac.in
Homepage: http://www.lisbic.com
Prof. Ray J. Butcher
Department of Chemistry
Howard University
Washington, D.C. 20059, United States
Both authors contributed equally
[b]
[‡]
Furthermore, solid-state structure of [Ni(L1)Cl2] exhibited
a
This article is protected by copyright. All rights reserved.

10.1002/ejic.201801471
European Journal of Inorganic Chemistry
Communication
Communication
[22] T. Jahns, R. Schepp, C. Siersdorfer, H. Kaltwasser, Acta Biol.
Hung. 1998, 49, 449-454.
[23] U. Ermler, W. Grabarse, S. Shima, M. Goubeaud, R. K. Thauer,
Science 1997, 278, 1457-1462.
[24] H. D. Youn, E. J. Kim, J. H. Roe, Y. C. Hah, S. O. Kang,
Biochem. J. 1996, 318, 889-896.
[25] J. Wuerges, J. W. Lee, Y. I. Yim, H. S. Yim, S. O. Kang, K. D.
Carugo, Proc. Natl. Acad. Sci. U. S. A. 2004, 101, 8569-8574.
[26] G. D. Straganz, B. Nidetzky, ChemBioChem 2006, 7, 1536-
1548.
[27] F. Al-Mjeni, T. Ju, T. C. Pochapsky, M. J. Maroney,
Biochemistry 2002, 41, 6761-6769.
[28] T. C. Pochapsky, S. S. Pochapsky, T. T. Ju, H. P. Mo, F. Al-
Mjeni, M. J. Maroney, Nat. Struct. Biol. 2002, 9, 966-972.
[29] Y. Dai, P. C. Wensink, R. H. Abeles, J. Biol. Chem. 1999, 274,
1193-1195.
[30] H. P. Mo, Y. Dai, S. S. Pochapsky, T. C. Pochapsky, J. Biomol.
NMR 1999, 14, 287-288.
[31] R. W. Myers, J. W. Wray, S. Fish, R. H. Abeles, J. Biol. Chem.
1993, 268, 24785-24791.
three isolated mimic-substrate adducts the anionic substrate is
bound to the nickel center as bidentate chelate as hypothesized
earlier.[35]
[Ni(L2)(OOCPh)]+ (observed m/z is 531.2289; calcd. m/z is
531.2270; Fig. S25, S26) were present in the ESI-MS (Scheme
3). In addition, the 1H NMR of isolated organic components upon
protonation confirms the presence of benzoic acid (Fig. S27).
To the best of our knowledge, the enzyme-substrate models
reported to date reactive towards dioxygen only when the
substrate is 2-hydroxy-3-oxo-1,3-diphenylprop-1-en-1-olate (A2)
that is closer to the natural substrate, acireductone. Only in one
case where the oxidative cleavage is initiated photochemically,
The authors declare no conflict of interest.
Keywords: Acireductone dioxygenase • Enzyme-substrate
mimic • Nickel complexes • Aerial oxidation • Aliphatic C-C
cleavage
[1] J. B. Sumner, J. Biol. Chem. 1926, 69, 435-441.
[2] N. E. Dixon, C. Gazzola, R. L. Blakeley, B. Zerner, J. Am.
Chem. Soc. 1975, 97, 4131-4133.
[3] P. A. Karplus, M. A. Pearson, R. P. Hausinger, Acc. Chem.
Res. 1997, 30, 330-337.
[4] E. Jabrie, M. B. Carr, R. P. Hausinger, P. A. Karplus, Science
1995, 268, 998-1004.
[5] T. I. Doukov, L. C. Blasiak, J. Seravalli, S. W. Ragsdale, C. L.
Drennan, Biochemistry 2008, 47, 3474-3483.
[6] T. I. Doukov, H. Hemmi, C. L. Drennan, S. W. Ragsdale, J.
Biol. Chem. 2007, 282, 6609-6618.
[7] C. L. Drennan, T. I. Doukov, S. W. Ragsdale, J. Biol. Inorg.
Chem. 2004, 9, 511-515.
[8] T. I. Doukov, T. M. Iverson, J. Seravalli, S. W. Ragsdale, C. L.
Drennan, Science 2002, 298, 567-572.
[9] C. L. Drennan, J. Y. Heo, M. D. Sintchak, E. Schreiter, P. W.
Ludden, Proc. Natl. Acad. Sci. U. S. A. 2001, 98, 11973-11978.
[10] H. Dobbek, V. Svetlitchnyi, L. Gremer, R. Huber, O. Meyer,
Science 2001, 293, 1281-1285.
[11] J. Seravalli, W. W. Gu, A. Tam, E. Strauss, T. P. Begley, S. P.
Cramer, S. W. Ragsdale, Proc. Natl. Acad. Sci. U. S. A. 2003,
100, 3689-3694.
[12] P. A. Lindahl, Biochemistry 2002, 41, 2097-2105.
[13] E. L. Maynard, P. A. Lindahl, J. Am. Chem. Soc. 1999, 121,
9221-9222.
[14] M. M. He, S. L. Clugston, J. F. Honek, B. W. Matthews,
Biochemistry 2000, 39, 8719-8727.
[15] Z. D. Su, N. Sukdeo, J. F. Honek, Biochemistry 2008, 47,
13232-13241.
[16] N. Sukdeo, E. Daub, J. F. Honek, in Nickel and Its Surprising
Impact in Nature (Eds.: A. Sigel, H. Sigel, R. K. O. Sigel), John
Wiley & Sons, New York, 2007, pp. 445-471.
[17] A. Volbeda, M. H. Charon, C. Piras, E. C. Hatchikian, M. Frey,
J. C. Fontecilla-Camps, Nature 1995, 373, 580-587.
[18] Y. Higuchi, T. Yagi, N. Yasuoka, Structure 1997, 5, 1671-1680.
[19] Y. Montet, P. Amara, A. Volbeda, X. Vernede, E. C. Hatchikian,
M. J. Field, M. Frey, J. C. FontecillaCamps, Nat. Struct. Biol.
1997, 4, 523-526.
[20] E. Garcin, X. Vernede, E. C. Hatchikian, A. Volbeda, M. Frey, J.
C. Fontecilla-Camps, Structure 1999, 7, 557-566.
[21] P. M. Matias, C. M. Soares, L. M. Saraiva, R. Coelho, J.
Morais, J. Le Gall, M. A. Carrondo, J. Biol. Inorg. Chem. 2001,
6, 63-81.
the
substrate
A4
is
cleaved.[41]
Even
though,
[Ni(BBP)(A3)(H2O)Cl2] undergoes C-C cleavage in the presence
of dioxygen, the mechanism proposed involves binding of oxygen
on Ni whereas the wild-type enzyme-substrate mimic does not go
through such intermediate;[45] owing to the labile aqua ligand
bound to the [Ni(BBP)(A3)(H2O)Cl2], the proposed [Ni-O-O-C-
substrate]‡ intermediate might be possible.[45]
[32] Y. Dai, T. C. Pochapsky, R. H. Abeles, Biochemistry 2001, 40,
6379-6387.
[33] J. W. Wray, R. H. Abeles, J. Biol. Chem. 1995, 270, 3147-3153.
[34] A. R. Deshpande, K. Wagenpfeil, T. C. Pochapsky, G. A.
Petsko, D. Ringe, Biochemistry 2016, 55, 1398-1407.
[35] E. Szajna, A. M. Arif, L. M. Berreau, J. Am. Chem. Soc. 2005,
127, 17186-17187.
[36] E. Szajna-Fuller, K. Rudzka, A. M. Arif, L. M. Berreau, Inorg.
Chem. 2007, 46, 5499-5507.
[37] K. Rudzka, A. M. Arif, L. M. Berreau, Inorg. Chem. 2008, 47,
10832-10840.
Conclusions
In summary, we have shown that two paramagnetic
nickel(II) complexes of macrocyclic N4 ligands are able to perform
as enzyme-substrate mimic for nickel containing acireductone
dioxygenase enzyme. For the first time, aerial oxygen was utilised
in the oxidative cleavage of aliphatic C-C bonds of acireductone
model substrate. Our future works are dedicated towards design
and synthesis of N3O ligands and their Ni(II) complexes with an
anionic O donor as such type of models would be closer to the
natural ligand environment of acireductone dioxygenase active
site.
[38] K. Rudzka, K. Grubel, A. M. Arif, L. M. Berreau, Inorg. Chem.
2010, 49, 7623-7625.
Figure 5. Solid-state structures of [Ni(L2)(A1)](BPh4) (left), [Ni(L2)(A3)](BPh4)
(right) and [Ni(L2)(A4)](BPh4) (bottom). Solvents, counter anions and hydrogens
are omitted for sake of clarity. Selected bond distances [Å] of [Ni(L2)(A1)](BPh4):
Ni-N(4), 1.9877(18); Ni-O(1), 1.9986(15); Ni-N(1), 2.0000(19); Ni-O(2),
2.0023(15); Ni-N(3), 2.3201(19); Ni-N(2), 2.3252(19). Selected bond distances
[Å] of [Ni(L2)(A3)](BPh4): Ni-O(1), 1.978(4); Ni-N(1), 1.980(5); Ni-N(3), 1.983(5);
Ni-O(2), 1.994(4); Ni-N(2), 2.291(4); Ni-N(4), 2.320(4). Selected bond distances
[Å] of [Ni(L2)(A4)](BPh4): Ni-N(1), 1.971(5); Ni-O(2), 1.979(4); Ni-N(3), 1.979(4);
Ni-O(1), 1.995(3); Ni-N(2), 2.290(4); Ni-N(4), 2.293(4). More details are
provided as supporting information (Figures S17-S19; Table S3-S5).
[39] K. Grubel, A. L. Fuller, B. M. Chambers, A. M. Arif, L. M.
Berreau, Inorg. Chem. 2010, 49, 1071-1081.
[40] L. M. Berreau, T. Borowski, K. Grubel, C. J. Allpress, J. P.
Wikstrom, M. E. Germain, E. V. Rybak-Akimova, D. L. Tierney,
Inorg. Chem. 2011, 50, 1047-1057.
[41] C. J. Allpress, A. M. Arif, D. T. Houghton, L. M. Berreau,
Chem.-Eur. J. 2011, 17, 14962-14973.
[42] C. J. Allpress, L. M. Berreau, Coord. Chem. Rev. 2013, 257,
3005-3029.
[43] C. J. Allpress, L. M. Berreau, Eur. J. Inorg. Chem. 2014, 4642-
4649.
[44] K. Grubel, G. K. Ingle, A. L. Fuller, A. M. Arif, L. M. Berreau,
Dalton Trans. 2011, 40, 10609-10620.
[45] R. Ramasubramanian, K. Anandababu, M. Kumar, R.
Mayilmurugan, Dalton Trans. 2018, 47, 4049-4053.
Supporting Information Summary
+
+
R
The experimental details, 1H NMR and ESI-mass spectra,
ORTEPs, crystallographic details are available in the Supporting
R
Ph
Triethylamine
Acetonitrile
Aerial O2
N
N
N
N
N
N
Ph
O
Ph
O
O
Information.
CCDC
1881017
([Ni(L1)Cl2]),
1881018
OH
OH
Ph
Ni
Ni
O
([Ni(L2)(CH3CN)2](BPh4)2×CH3CN), 1881019 ([Ni(L2)(A1)](BPh4)),
1881020 ([Ni(L2)(A3)](BPh4)) and 1881021 ([Ni(L2)(A4)](BPh4))
contain the supplementary crystallographic data for this paper.
These data can be obtained free of charge from The Cambridge
Crystallographic Data Centre.
O
CO
N
N
R
R
Scheme 3. Aliphatic C-C bond cleavage of A2 in the presence of triethylamine
and aerial oxygen at room temperature (R = Bn or tBu).
The oxidative cleavage of model acireductone substrates
(A1-A4) have been carried out using
a
mixture of
Acknowledgments
[Ni(L1)(CH3CN)2](BPh4)2 or [Ni(L2)(CH3CN)2](BPh4)2 and the
substrate precursors HA1-HA4 in addition to 4 equivalents of
triethylamine in acetonitrile under ambient conditions in open air
(Scheme 3). The resulting solutions were analyzed preliminarily
employing ESI-MS and it was observed that the substrates A1,
A3 and A4 did not undergo C-C bond cleavage instead stable
substrate-adduct species were observed (Fig. S20-S22); this is in
line with the observations of Berreau.[36] As expected, the
substrate A2, that is closer to the acireductone (RC(=O)C(-
OH)=CHOH), underwent oxidative C-C bond cleavage utilizing
aerial oxygen, as the envelopes for [Ni(L1)(OOCPh)]+ (observed
m/z is 599.1993; calcd. m/z is 599.1957; Fig. S23, S24) and
Science and Engineering Research Board, Department of
Science and Technology, India (EMR/2015/001350) and Indian
Institute of Technology Kanpur sponsored this research. S.R.
acknowledges the Council of Scientific & Industrial Research
(CSIR, India) for his Senior Research Fellowships. KM thanks
Indian Institute of Technology Kanpur (IITK) for the stipend. PK
acknowledges DST, India for a grant through Fast Track Scheme
for Young Scientists (SB/FT/CS-153/2014).
Conflict of Interest
This article is protected by copyright. All rights reserved.

10.1002/ejic.201801471
European Journal of Inorganic Chemistry
Communication
Entry for the Table of Contents
+
+
R
R
Ph
Triethylamine
Acetonitrile
Aerial O2
N
N
N
N
N
N
Ph
O
Ph
O
O
OH
OH
Ph
Ni
Ni
O
O
CO
N
N
R
R
Nickel Aci-reductone Dioxygenase Mimic: Bioinspired oxidative cleavage of aliphatic C-C bonds of acireductone model substrate,
2-hydroxy-3-oxo-1,3-diphenylprop-1-en-1-olate, bound to two paramagnetic nickel(II) complexes that are mimics for the nickel
containing acireductone dioxygenase has been achieved utilizing aerial oxygen under ambient conditions.
This article is protected by copyright. All rights reserved.