Inorganic Chemistry
Article
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[(pL5 )Fe(OTf)](OTf) 3b. In a glovebox, a solution of Fe-
ASSOCIATED CONTENT
* Supporting Information
Detailed synthetic procedures. Details of X-ray structural
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(OTf)2·2MeCN (0.27 mmol, 0.12 g) in acetonitrile/ethanol (1/1 mL)
was added to a stirred solution of pL5 (0.27 mmol, 0.1 g) in ethanol
S
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(5 mL). The addition of diethyl ether and acetonitrile resulted in a
color change of the solution from brown to yellow. Cooling down the
mixture at 4 °C gave a precipitate. The solid was filtered off, washed
with diethyl ether (5 mL), and dried under vacuum to afford a brown
powder in 49% yield (0.10 g).
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analysis for complexes 1a (mpL4 )FeCl2, 3a [(pL5 )FeCl]-
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3
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(PF6), 4b [(tL5 )Fe](PF6)2, 5a [(pL5 )FeCl](PF6), 5b [(pL5 )-
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Fe(OTf)](OTf), and 6b [(tL5 )Fe](PF6)2, additional UV−
visible, electrochemical, EPR, electrochemical and ESI-MS data.
This material is available free of charge via the Internet at
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[(pL5 )Fe(OTf)](OTf) 5b. In a glovebox, a solution of Fe-
(OTf)2·2MeCN (0.26 mmol, 0.11 g) in ethanol (5 mL) was added to
a stirred solution of pL5 (0.26 mmol, 0.1 g) in ethanol (5 mL). The
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mixture was cooled down to −12 °C to yield yellow crystals suitable
AUTHOR INFORMATION
Corresponding Author
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for X-ray crystallography (0.081 g, 42% yield).
Catalytic Assays. Conditions were FeII/H2O2 or PhIO/substrate:
1/20 or 2/800 (cyclohexane and cyclooctene) or 3000 (anisole) in
freshly distilled acetonitrile solvent,. The total concentration in Fe was
1 mM. PhIO was added prior the substrate to ensure the formation of
the FeIV(O) complex. Note that the oxidant was previously dissolved
in the minimum amount of methanol, which did not impact the
concentration in the reactants.
Notes
The authors declare no competing financial interest.
REFERENCES
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X-ray Crystallography. X-ray diffraction data for 1a (mpL4 )-
(1) (a) Girerd, J. J.; Banse, F.; Simaan, A. J. Struct. Bonding (Berlin)
2000, 97, 145. (b) Korendovych, I. V.; Kryatov, S. V.; Rybak-Akimova,
E. V. Acc. Chem. Res. 2007, 40, 510. (c) Prat, I.; Mathieson, J. S.; Guell,
M.; Ribas, X.; Luis, J. M.; Cronin, L.; Costas, M. Nat. Chem. 2011, 3,
788. (d) Que, L., Jr. Acc. Chem. Res. 2007, 40, 493. (e) Seo, M. S.; Kim,
N. H.; Cho, K. B.; So, J. E.; Park, S. K.; Clemancey, M.; Garcia-Serres,
R.; Latour, J. M.; Shaik, S.; Nam, W. Chem. Sci. 2011, 2, 1039.
(2) (a) Martinho, M.; Banse, F.; Bartoli, J.-F.; Mattioli, T. A.;
Battioni, P.; Horner, O.; Bourcier, S.; Girerd, J.-J. Inorg. Chem. 2005,
44, 9592. (b) Thibon, A.; Bartoli, J.-F.; Bourcier, S.; Banse, F. Dalton
Trans. 2009, 9587.
(3) Collins, T. J. Acc. Chem. Res. 2002, 35, 782.
(4) Jollet, V. Ph.D. Thesis, n° d’ordre 10491, University Paris Sud,
Orsay, France, 2011.
(5) Rostovtsev, V. V.; Green, L. G.; Fokin, V. V.; Sharpless, K. B.
Angew. Chem., Int. Ed. 2002, 41, 2596.
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FeCl2, 3a [(pL5 )FeCl](PF6), 5a [(pL5 )FeCl](PF6), 4b [(tL5 )Fe]-
3
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(PF6)2, 6b [(tL5 )Fe](PF6)2, and 5b [(pL5 )Fe(OTf)](OTf) were
collected by using a Kappa X8 APPEX II Bruker diffractometer with
graphite-monochromated MoKα radiation (λ = 0.71073 Å). Crystals
were mounted on a CryoLoop (Hampton Research) with Paratone-N
(Hampton Research) as cryoprotectant and then flashfrozen in a
nitrogen-gas stream at 100 K. The temperature of the crystal was
maintained at the selected value (100 K) by means of a 700 series
Cryostream cooling device to within an accuracy of 1 K. The data
were corrected for Lorentz polarization, and absorption effects. The
structures were solved by direct methods using SHELXS-9737 and
refined against F2 by full-matrix least-squares techniques using
SHELXL-9738 with anisotropic displacement parameters for all non-
hydrogen atoms. Hydrogen atoms were located on a difference Fourier
map and introduced into the calculations as a riding model with
isotropic thermal parameters. All calculations were performed by using
the Crystal Structure crystallographic software package WINGX.39
The absolute configuration was determined by refining the Flack40
parameter using a large number of Friedel’s pairs.
(6) (a) Collman, J. P.; Devaraj, N. K.; Decreau, R. A.; Yang, Y.; Yan,
Y. L.; Ebina, W.; Eberspacher, T. A.; Chidsey, C. E. D. Science 2007,
315, 1565. (b) Decreau, R. A.; Collman, J. P.; Yang, Y.; Yan, Y.;
́
Devaraj, N. K. J. Org. Chem. 2007, 72, 2794. (c) Devaraj, N. K.;
Dinolfo, P. H.; Chidsey, C. E. D.; Collman, J. P. J. Am. Chem. Soc.
2006, 128, 1794. (d) Gomila, A.; Le Poul, N.; Cosquer, N.; Kerbaol, J.
M.; Noel, J. M.; Reddy, M. T.; Jabin, I.; Reinaud, O.; Conan, F.; Le
Mest, Y. Dalton Trans. 2010, 39, 11516. (e) Schweinfurth, D.;
Demeshko, S.; Khusniyarov, M. M.; Dechert, S.; Gurram, V.;
Buchmeiser, M. R.; Meyer, F.; Sarkar, B. Inorg. Chem. 2012, 51, 7592.
(7) (a) Hao, E. R.; Wang, Z. Y.; Jiao, L. J.; Wang, S. W. Dalton Trans.
2010, 39, 2660. (b) Ostermeier, M.; Berlin, M. A.; Meudtner, R. M.;
Demeshko, S.; Meyer, F.; Limberg, C.; Hecht, S. Chem.Eur. J. 2010,
16, 10202. (c) Li, Y. J.; Huffman, J. C.; Flood, A. H. Chem. Commun.
2007, 2692.
The crystal data collection and refinement parameters are given in
Supporting Information.
CCDC 890269−890274 contains the supplementary crystallo-
graphic data for this paper. These data can be obtained free of charge
from the Cambridge Crystallographic Data Centre via www.ccdc.cam.
UV−visible. Electronic absorption spectra were recorded with a
Varian Cary 50 spectrophotometer equipped with a Hellma immersion
probe (1 cm optical path length) and fiber-optic cable. For low
temperature experiments, a Thermo Haake CT90L cryostat was used.
Gas chromatography was performed on a Varian 430-GC equipped
with a PDMS VF-1 ms column (15 m × 0.25 mm).
ESI-MS experiments were carried out with a Bruker Daltonics
MicrOTOFq mass spectrometer in positive mode acquisition. Sample
solutions prepared in acetonitrile or MeOH at a concentration of
about 1 mM were infused at a flow rate of 10 μL min−1 with a CIL
Cluzeau (Courbevoie, France) syringe. Solutions of FeIV(O)
intermediates were frozen in liquid nitrogen and thawed just before
injection.
EPR spectra were recorded at 9 GHz with a Bruker ELEXSYS 500
spectrometer equipped with a continuous flow Oxford E900 cryostat.
Electrochemical measurements were performed with an Autolab
electrochemical workstation. The solvents were distilled under argon
in the presence of CaH2 and the solution (2 mmol L−1 for complexes
and 0.1 mol·L−1 of TBAPF6) introduced within an argon-purged heart-
shaped cell. Cyclic voltammetry was performed using a glassy carbon
electrode (3 mm in diameter) as the working electrode and a saturated
calomel electrode as the reference (Eref = 0.24 V/NHE). The low
temperature was conducted using a Julabo FP 50 cryostat.
(8) Abbreviations used. TAML: tetraamido macrocyclic ligands;
TPEN: (N,N,N′,N′-tetrakis(2-pyridylmethyl)ethane-1,2-diamine);
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L6 4E: N,N,N′,N′-tetrakis(5-ethyl-2-pyridylmethyl)ethane-1,2-dia-
2
mine; m2L4 : N,N′-dimethyl-N,N′-bis(2-pyridylmethyl)-1,2-diamino-
2
ethane; mL5 : N-methyl-N,N′,N′-tris(2-pyridylmethyl)-1,2-diamino-
2
ethane; mpL4 : N-Methyl-N′-(prop-2-ynyl)-N,N′-bis-(pyridin-2-yl-
2
methyl)-ethane-1,2-diamine; mtL4 : N-Methyl-N′-(1-(4-Methoxy-
phenyl)-1H-[1,2,3]triazol-4-ylmethyl)-N,N′-bis-(pyridin-2-ylmethyl)-
2
ethane-1,2-diamine; pL5 : N-(Prop-2-ynyl)-N,N′,N′-tris-(pyridin-2-
2
ylmethyl)-ethane-1,2-diamine; tL5 : N-(1-(4-Methoxy-phenyl)-1H-
[1,2,3]triazol-4-ylmethyl)-N,N′,N′-tris-(pyridin-2-ylmethyl)-ethane-
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1,2-diamine; pL5 : N-(Prop-2-ynyl)-N,N′,N′-tris-(pyridin-2-ylmethyl)-
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propane-1,3-diamine; tL5 : N-(1-(4-Methoxy-phenyl)-1H-[1,2,3]tria-
zol-4-ylmethyl)-N,N′,N′-tris-(pyridin-2-ylmethyl)-propane-1,3-dia-
mine; TPA: tris(2-pyridylmethyl)amine; N4Py: N,N-bis(2-pyridyl-
methyl)-bis(2-pyridyl)methylamine.
(9) (a) Balland, V.; Banse, F.; Anxolabehere Mallart, E.; Nierlich, M.;
Girerd, J. J. Eur. J. Inorg. Chem. 2003, 2529. (b) Mialane, P.;
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dx.doi.org/10.1021/ic301834x | Inorg. Chem. XXXX, XXX, XXX−XXX