A monomeric copper-phosphoramide complex: Synthesis, structure, and electronic properties

Article abstract of DOI:10.1016/j.poly.2016.07.042

We report on a novel phosphoramide complex with formula Cu(NO₃)₂([C₅H₁₀N]₃PO)₂. This complex is the first example of a copper monomeric phosphoric triamide having an octahedral Cu[O]₆coordination environment. Cu(NO₃)₂([C₅H₁₀N]₃PO)₂crystallizes in the monoclinic space group P2₁/n with the Cu atom located at an inversion center, as determined by single-crystal X-ray diffraction. Magnetic measurements along the principal crystallographic directions of the single crystal indicate that the complex is a paramagnet with very low magnetic anisotropy. Electron paramagnetic resonance spectra reveal the presence of two Cu²⁺sites and make it possible to extract the hyperfine coupling.

Full text of DOI:10.1016/j.poly.2016.07.042

Accepted Manuscript
A monomeric copper-phosphoramide complex: synthesis, structure, and elec-
tronic properties
Margarida S. Henriques, Denis I. Gorbunov, Alexey N. Ponomaryov, Anahid
Saneei, Mehrdad Pourayoubi, Michal Dušek, Sergey Zvyagin, Marc Uhlarz,
Joachim Wosnitza
PII:
S0277-5387(16)30339-4
DOI:
http://dx.doi.org/10.1016/j.poly.2016.07.042
POLY 12136
Reference:
Polyhedron
To appear in:
Received Date:
Revised Date:
Accepted Date:
31 May 2016
26 July 2016
28 July 2016
Please cite this article as: M.S. Henriques, D.I. Gorbunov, A.N. Ponomaryov, A. Saneei, M. Pourayoubi, M.
Dušek, S. Zvyagin, M. Uhlarz, J. Wosnitza, A monomeric copper-phosphoramide complex: synthesis, structure,
and electronic properties, Polyhedron (2016), doi: http://dx.doi.org/10.1016/j.poly.2016.07.042
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A monomeric copper-phosphoramide complex: synthesis, structure, and electronic properties
Margarida S. Henriques1*, Denis I. Gorbunov2*, Alexey N. Ponomaryov2, Anahid Saneei3,
Mehrdad Pourayoubi3, Michal Dušek1, Sergey Zvyagin2, Marc Uhlarz2, Joachim Wosnitza2
1Institute of Physics, Academy of Sciences of the Czech Republic, Na Slovance 2, 182 21
Prague, Czech Republic
2Dresden High Magnetic Field Laboratory (HLD-EMFL), Helmholtz-Zentrum Dresden-
Rossendorf, D-01314 Dresden, Germany
3Department of Chemistry, Faculty of Sciences, Ferdowsi University of Mashhad, Vakil Abad
Blvd., Azadi Square, Mashhad, P. O. Box 9177948974, Iran
KEYWORDS. Phosphoramide, Magnetization, EPR
ABSTRACT. We report on a novel phosphoramide complex with formula
Cu(NO3)2([C5H10N]3PO)2. This complex is the first example of a copper monomeric phosphoric
triamide. Cu(NO3)2([C5H10N]3PO)2 crystallizes in the monoclinic space group P21/n with the Cu
atom located at an inversion center and having an octahedral Cu[O]6 coordination environment,
1

as determined by single-crystal X-ray diffraction. Magnetic measurements along the principal
crystallographic directions of the single crystal indicate that the complex is a paramagnet with
very low magnetic anisotropy. Electron paramagnetic resonance spectra reveal the presence of
two Cu2+ sites and make it possible to extract the hyperfine coupling.
1. INTRODUCTION
Phosphoramide-based compounds (scheme 1a) have been thoroughly reported as potent
inhibitors of the enzymes urease [1-3], acetylcholinesterase [4-7], and butyrylcholinesterase [8].
Effective inhibition is found not only in simple compounds like phosphoramide and
diamidophosphate but extends to substituted molecules as phenyl phosphorodiamides or n-acyl
phosphoric triamides [1]. The enzymatic inhibition has important impact on potential
applications for this type of compounds. In clinical sciences and pharmaceutics, phosphoramides
(PA) can be used in therapies and drug design against bacterial ureases, which are implicated in
the pathogenesis of many clinical conditions [2-4], or as retardants and/or modulators of vital
pathological responsive processes of the cholinesterases to cholinergic toxins, xenobiotics or
aging of the central nervous system [4-8]. Series of PA derivatives were synthesized and studied
as potential chemotherapeutic agents against cancer and parasitic diseases [9]. In agriculture, the
incorporation of urease inhibitors is recommended as preferable practice for the efficient use of
urea fertilizers, reduction of soil nitrate loss and release of greenhouse gases by controlling the
pH and hydrolysis of urea in the soil [1]. In addition, PA are also known by their biocidal activity
2

and have been applied as pesticides and insecticides [6,10,11]. Other important applications
include their use as analytical tool to determine the kinetics and activity of other enzyme
inhibitors [1], as appropriate ligands in coordination chemistry [12-15] or as potent catalysts for
a wide variety of chemical reactions in organic synthesis [16-19]. The very efficient
enantioselectivity of chiral PA in allylation reactions is known to be intimately correlated with
the crystal structure [16]. In fact, the highly asymmetric backbones and chiral centers of PA are
the features pointed as stereo-chemically relevant to the modulation of the asymmetric
environment of the metallic reaction centers and to the promotion of asymmetric induction
during these reactions. Thus, most attention has been concentrated on the synthesis,
spectroscopic, and structural investigation of PA regarding predominantly their chemical
properties.
Less extensive work exploring the physical properties of complexes with PA as ligands can be
found in literature. Rare-earth neutral complexes containing PA ligands have been published
describing their intense luminescence, particularly for the Eu3+, and pointing them as good
candidates to phosphors [20-22]. A centrosymmetric complex of europium with a
hexamethylphosphoramide ligand was reported to exhibit intense triboluminescence promoted
by an effective charge polarization due to the strong donor properties of the PA groups [23].
Heterometallic anionic clusters synthesized with PA ligand in their skeleton form one-
dimensional anionic chains which show interesting nonlinear optical properties [24]. Curie and
Pauli paramagnetic behaviors were found in Co and Ni PA complexes [25]. The analysis of the
mean magnetic susceptibilities and anisotropy of the different complexes was discussed based on
the hypothesis of different electron delocalization in the metal-ligand bonds and distinct charge
distribution in the ligands.
3

The scarcity of works on the crystal chemistry and physical properties of PA and their promising
wide range of applications lead us to the synthesis of the new phosphoric triamide complex
Cu(NO3)2([ (C5H10N)3PO]2 and a study of its crystal structure, magnetism, and electronic
structure. Moreover, the CuII-phosphoramide chemistry may attract attention due to the CuII
“plastic” metal center (with versatile coordination numbers and modes, and possibility of
distortion) [26, 27], and to the potential role of the phosphoramide compounds as ligands in
coordination chemistry. The bis(nitrato-O,O')-bis(tripiperidinophosphineoxide-O)-copper(II)
compound (scheme 1b) crystallizes in the monoclinic space group P21/n and is the first example
of a monomeric copper phosphoric triamide complex with a Cu[O]6 coordination environment.
The compound is a Curie paramagnet with low magnetic anisotropy. Electron paramagnet
resonance spectroscopy shows hyperfine interactions between the unpaired electron and the
nucleus in Cu2+.
Scheme 1 – (a) General structural formula of phosphoramide-based compounds, where –R1 and
R2 refer to organic groups or H, and X and W may be either NRmRm+1, ORn, OH or halogen. If the
N atom belongs to a ring, R' bonds to N instead of NR1R2. We bring the following simple
examples of a general nomenclature: phosphoric triamide, phosphoramidate ester,
phosphoramidic acid, and phosphoramidic chloride for (NH2)3P(O), (NH2)P(O)(OCH3)2,
4

(NH2)P(O)(OH)2, and (NH2)P(O)Cl2, respectively. The names noted can also be used if the
amino group is substituted, and different OR groups used instead of OCH3 in the
phosphoramidate ester family [28]. (b) Structural scheme of the phosphoramide complex
Cu(NO3)2([C5H10N]3PO)2.
EXPERIMENTAL SECTION
1.1. Synthesis
Tripiperidinophosphine oxide, [C5H10N]3PO. The ligand, [C5H10N]3PO, was previously
reported to form as a by-product in a reaction yielding {[C5H10N]4P}Br [29]. Here, the synthesis
of [C5H10N]3PO was performed by a different method summarized by Eq. 1 and described as
follows: a solution of piperidine (6 mmol) in dry acetonitrile (5 ml) was added dropwise to a
solution of P(O)Cl3 (1 mmol) in the same solvent (30 ml) at 273 K. After stirring for 4 h, the
precipitated amine hydrochloride salt (C5H10NH.HCl) was filtered, and the acetonitrile solution
of the ligand was used in the complex reaction.
dry CH CN, 273 K
ꢀ
POCl3 + 6 C5H10NH ꢁꢂꢂꢂꢂꢂꢂꢂꢂꢂꢂꢂꢃ PO(NC5H10)3 (sol) + 3 C5H10NH. HCl (pre)
Eq. 1
Bis(nitrato-O,O')-bis(tripiperidinophosphine oxide-O)-copper(II),
Cu(NO3)2([C5H10N]3PO)2. A solution of copper(II) nitrate trihydrate (1 mmol) in methanol (5
ml) was added dropwise to a solution of the ligand (2 mmol). The clear solution was stirred
under reflux for 48 h (Eq. 2). Blue crystals were obtained after a few days at room temperature.
CH OH, 48 h, reflux
3
2 PO(NC5H10)3 (sol) + Cu(NO3)2. 3H2O ꢁꢂꢂꢂꢂꢂꢂꢂꢂꢂꢂꢂꢃ Cu(NO3)2([C5H10N]3PO)2
Eq. 2
5

Yield: 72 %. F.p. 146–149 ºC. Elemental analyses (C, H, N) were performed on a Thermo
Finnigan Flash 1112EA elemental analyzer. Melting points were determined using a Thermo
Scientific IA-9300 apparatus. Anal. Calc. for C30H60Cu1N8O8P2 (768.4): C, 45.82; H, 7.69; N,
14.25. Found: C, 44.23; H, 7.14; N, 13.97.
The infrared (IR) spectrum was recorded on a Buck 500 scientific spectrometer with the sample
prepared as KBr pellet. In the IR data resonance lines were found at (cm−1): 2932, 2852, 1740,
1485, 1442, 1384, 1283, 1211, 1167, 1133, 1071, 1024, 957, 864, 726. In the IR data, resonance
lines were found at (cm−1): 2932, 2852, 1740, 1485 (NOstret), 1442, 1384, 1283 (NO2 as, stret),
1211, 1167, 1133, 1071, 1024 (NO2 s, stret), 957, 864 (NO2 s, bend), 726 (NO2 as, bend). The highest
frequency band of the nitrate ligand is indicative of a double nitrogen-oxygen bond, confirming
the coordinated bidentate nitrate anions, similar to what was previously reported for
UO2(NO3)2([C5H10N]3P(O))2 (of 1442 cm–1) [30].
1.1. Characterization methods.
Single-crystal X-ray diffraction. Single crystals of Cu(NO3)2([C5H10N]3PO)2 were mounted on
the top of a glass fiber and attached onto a goniometer head. The crystal was optically aligned on
a four-circle X-ray diffractometer Gemini of Agilent equipped with a Mo-Enhance collimator
and graphite monochromator. The sample temperature was set at 120 K and the diffracted
intensities were collected by use of a CCD detector Atlas using Cu radiation (λ = 1.54056 Å).
The CrysAlis [31] package was used for data acquisition and reduction, whereas the Superflip
[32] program was employed for structure solution and Jana2006 [33] for structure refinement.
Details on the data collection and refinement procedure, lattice parameters, and final refinement
6

factors are given in Table 1. Further information on data collection and crystal structure
investigation is included in the CIF file deposited as Supporting Information.
Magnetometry. Temperature and field dependences of the magnetization for fields applied
along the [100], [101], and [001] axes were measured on a 0.7 mg single-crystalline sample
using a commercial vibrating-sample magnetometer (Physical Property Measurement System,
Quantum Design) in fields up to 14 T. The curves presented below were corrected for the
contribution of the sample holder.
Electron paramagnetic resonance (EPR) spectroscopy. The EPR experiments on a
Cu(NO3)2([C5H10N]3PO)2 single crystal were performed at the High Magnetic Field Laboratory
(HLD-EMFL) in Dresden, Helmholtz-Zentrum Dresden-Rossendorf. The low-frequency EPR
spectra were recorded by means of an X-band Bruker Elexsys E500 EPR spectrometer operated
at 9.4 GHz. High-frequency high-field EPR spectra were measured using a spectrometer similar
to that described in Ref. 34. The spectrometer was equipped with a transmission-type probe in
the Faraday configuration and a 16 T superconducting magnet (Oxford Instruments). The
microwave sources (Virginia Diodes Inc.) allowed us to measure EPR spectra in the frequency
range 60 – 500 GHz. The measurements were performed between 1.5 and 300 K using a He4
gas-flow cryostat.
2. RESULTS AND DISCUSSION
2.1. Crystal structure description
The crystal structure of Cu(NO3)2([C5H10N]3PO)2 was established by single-crystal X-ray
diffraction. The molecular structure, and unit cell of the complex are shown in Fig. 1. This
7

compound crystallizes in the monoclinic space group P21/n with one half of a molecule in the
asymmetric unit and the Cu atom on a crystallographic inversion center (Fig. 1a and 1b). A view
of the molecular alignment along [101] is shown in Fig. 1c. The Cu center adopts an octahedral
Cu[O]6 environment in which the copper(II) ion is coordinated by two equivalent nitrate anions
as bidentate ligands in the equatorial plane and two equivalent tripiperidinophosphine oxide
ligands in the axial positions. The phosphoryl O atom makes a shorter Cu—O bond than the
nitrate O atoms (Table 2). The P atoms in the phosphoric triamide ligands adopt a distorted
P[O][N]3 tetrahedral environment and the Cu1—O2—P1 moiety is significantly bent with an
angle of 141.12 (6)°. Moreover, the P1═O2 bond length of 1.5010(8) Å is longer than the normal
phosphorus-oxygen double-bond length (1.45 Å) [28].
Table 1. Crystallographic data and experimental parameters for the complex
Cu(NO3)2([C5H10N]3PO)2.
Empirical formula
Formula weight
Crystal system
Space group
a, Å
C30H60Cu1N8O8P2
786.4
Monoclinic
P21/n
8.8830 (2)
17.1358 (3)
12.5983 (2)
90
b, Å
c, Å
α, deg
β, deg
103.1323 (17)
90
γ, deg
V, Å3
1867.53 (6)
2
Z
T, K
119.99(13)
1.54184
1.3984
λ, Å
ρcalcd, Mg/m3
8

µ, mm–1
2.119
F(000)
838
Theta range, deg
4.43 to 67.09
Index ranges
–10 ≤ h ≤ 10, –20 ≤ k ≤ 20, –14 ≤ l ≤ 14
29788
Reflections collected
Independent reflections
Refinement method
Data/restraints/parameters
Goodness-of-fit on F2
Final R indices
3327 [R(int) = 0.0283]
Full-matrix least-squares on F2
3327/0/223
1.82
R1 = 0.0263, wR2 = 0.0880
R1 = 0.0252, wR2 = 0.0868
0.56 and –0.43
R indices (all data)
Largest diff. peak and hole, e.Å–3
9

Figure 1. The structure of the phosphoramide complex Cu(NO3)2([C5H10N]3PO)2 as: (a) plot of
the anisotropic displacement ellipsoids (depicted at a probability level of 50%); (b) ball-and-stick
model of the complex in a projection of the monoclinic unit cell (light blue) along [100]; (c)
linear alignment of the monomeric units projected onto (101). The H atoms have been omitted in
all figures for the sake of clarity. The colors of each atom type represented correspond to the
color key indicated in the bottom part of the figure.
Table 2. Selected bond distances and angles (Å, deg) for Cu(NO3)2([C5H10N]3PO)2. Symmetry
code: (i) –x + 1, –y, −z.
Cu1–O1
Cu1–O1i
Cu1–O2
Cu1–O2i
Cu1–O3
Cu1–O3i
2.0493(10)
2.0493(10)
1.9201(9)
1.9201(9)
1.9802(10)
1.9802(10)
P1–O2
P1–N1
P1–N2
P1–N4
O1–N3
N3–O4
1.5010(8)
1.6426(11)
1.6436(11)
1.6436(12)
1.2456(17)
1.2276(18)
O1–Cu1–O1
O2–Cu1–O2
O2–Cu1–O3
180.0(1)
180.0(5)
90.16(4)
O2–P1–N1
O2–P1–N2
O2–P1–N4
N1–P1–N2
N1–P1–N4
N2–P1–N4
106.46(5)
108.23(5)
118.34(6)
112.75(6)
107.38(5)
103.87(6)
O2–Cu1–O3i 89.84(4)
O2i–Cu1–O3 89.84(4)
O2i–Cu1–O3i 90.16(4)
10

O3–Cu1–O3i 180.0(5)
Cu1–O2–P1 141.12(6)
O1–N3–O4
123.39(12)
In the crystal structure of Cu(NO3)2([C5H10N]3PO)2, two weak C3—H2C3…O2 and C9—
H2C9…O2 intramolecular interactions exist between the H atoms and the O2 atom, with H…O
distances of 2.42 and 2.41 Å (Table 3), respectively. A search in the Cambridge Structural
Database (CSD) [35] shows that this complex is the first example of a monomeric copper
phosphoric triamide complex with a Cu[O]6 coordination environment. As for the use of the
[C5H10N]3PO ligand, only two complexes have been reported so far in the CSD:
[C5H10N]3PO)3Pr(NCS)3 [22] and ([C5H10N]3PO)2U(NO3)2(O)2 [30].
Table 3. Hydrogen-bond geometries in Cu(NO3)2([C5H10N]3PO)2.
D―H…A
d(D―H)
0.96
d(H…A)
2.42
d(D…A)
∠(DHA)
111.47
113.27
C3—H2C3···O2
C9—H2C9···O2
2.9137(16)
2.9267(17)
0.96
2.41
It is noticeable that the shortest distance between the Cu ions is close to 9 Å. Such a large
distance prevents direct exchange interaction between the ions and suggests as well only weak
indirect exchange interactions. On the other hand, the bond lengths between the oxygen atoms in
the octahedral coordination of the Cu ion are different for equatorial and axial positions.
Nevertheless, the distances only differ by 6%, which points to a negligible Jahn-Teller
11

distortion. In general, the Jahn-Teller effect is most often found in octahedral Cu2+ complexes
with metal-ligand distances that differ in length by more than 20% [36].
2.2. Magnetism
Temperature dependences of the magnetization measured between 2 and 305 K indicate a
paramagnetic behavior without anomalies that would indicate magnetic phase transitions. This is
in line with the mentioned large distance between the Cu2+ ions. For a better presentation, Fig. 2
shows the static inverse susceptibility, 1/χ = µ0H/M, as a function of temperature for a field of 1
T applied along the principal crystallographic directions. The susceptibility follows the Curie law
χ= CT +χ0,
(1)
N
A
where C= 3k µ µ2eff is the Curie constant proportional to the square of the effective magnetic
B
0
moment, µeff. NA is the Avogadro constant, kB is the Boltzmann constant, µꢄ is the permeability
of free space, and ꢅꢄ is an additional temperature-independent term. µeff = 2.0 µB/f.u. was found
to be isotropic. This is a standard value per Cu2+ ion [37], as expected for a monomeric
compound. ꢅꢄ varies between 2.5×10-8 for [101] and 1.5×10-8 m3 mol-1 for [010]. The magnetic
susceptibility corresponds to the sum of the paramagnetic Cu[O]6 and the organic ligand with no
evidence for interaction between them. The Curie-like temperature dependence of the static
susceptibility was also found for Ni diphosphoramide complexes. This behavior is expected for S
= 1/2 systems with weak or no magnetic coupling or isolated magnetic ions [25,37].
The magnetization as a function of magnetic field at 2 K displays Brillouin-like behavior (inset
in Fig. 2). A weak magnetic anisotropy becomes evident with increasing field. In particular, the
12

magnetization for field applied along the [010] axis exhibits higher values than that for field
along the [101] and [001] axes. For the latter two directions, the magnetization behaves
identically. The highest magnetization values slightly exceed 1 µB/f.u. expected for a free Cu2+
ion. The additional small contribution may come from the ligand.
160
1.2
0.8
120
T = 2 K
[101]
[001]
[010]
0.4
80
40
0
0.0
0
2
4
6
8
10
12
14
µ0H (T)
µ0H = 1 T
Cu(NO3)2([C5H10N]3PO)2
0
50
100
150 200
T (K)
Figure 2. Temperature dependence of the inverse magnetic susceptibility for a field of 1 T
applied along the principal crystallographic directions. The inset shows the field-dependent
magnetization measured at 2 K for fields applied along the same directions.
2.3. Electron Paramagnetic Resonance
According to the crystal structure, the unit cell of Cu(NO3)2([C5H10N]3PO)2 contains a single
position for the Cu ions, which is an inversion center. Nevertheless, two magnetically
13

nonequivalent sites with coordination (0, 0, 0) and (½, ½, ½), might arise (best seen in Fig. 1b).
The molecule positioned in the center of the unit cell is identical to those in the corners;
however, its orientation with respect to the frame of reference of the unit cell is different. As
seen in Fig. 1b, this molecule is rotated counterclockwise by about 120° with respect to those in
the corners. Thus, despite the identical local g-tensors of the Cu2+ ions with gx, gy, and gz, where
x, y, and z are the axes of the molecule frame of reference, the values of ga, gb, and gc, with a, b,
and c being the unit-cell axes, will be different.
By taking the above mentioned into account, one may expect to observe at least two
resonance lines in the EPR spectra. However, the spectra measured for 9.4 GHz at 300 K display
a set of unresolved absorptions in the range between 0.26 and 0.34 T, indicating hyperfine
interactions between the unpaired electrons and the nucleus. Nevertheless, due to a possible
overlap of the hyperfine structures of the two magnetic sites, it was impossible to assign them.
However, as mentioned, these sites must have different g-factors, and thus, applying higher
microwave frequency and measuring spectra at higher magnetic fields, we were able to resolve
two sets of hyperfine structures.
Figure 3 shows the EPR spectrum measured at a microwave frequency of 90 GHz at 6 K,
with the magnetic field applied along the a axis. Here, two separated sets of absorption lines
appear, which belong to different magnetic centers in the unit cell. Each set consists of four lines.
With the electron spin S = 1/2 of the Cu2+ ions, and the Cu nuclear spin, I = 3/2, the four lines in
each set are the result of the hyperfine interaction between the electron and the nucleus. The inset
in Fig. 3 schematically shows the allowed transitions between the corresponding energy levels.
The Hamiltonian of the system is then
14

H = gµBHŜ + AÎŜ,
(2)
where g is the g-factor, Ŝ and Î are the electron and nuclear spins, respectively, and A is the
hyperfine interaction parameter [38]. This parameter can be estimated from the distance between
neighboring resonances in each set of lines. For the spectrum presented (Fig. 3) we determine A
equal to 0.375 GHz and 0.318 GHz for the left and the right sets, respectively, implying some
anisotropy.
Figure 3. EPR spectrum of a Cu(NO3)2([C5H10N]3PO)2 single crystal measured at 6 K and 90
GHz. The magnetic field was applied along the a axis. The inset shows the allowed transitions
between corresponding energy levels.
15

Experiments at higher frequencies up to 480 GHz allowed us to achieve a better
separation of the corresponding sets of lines. By taking into account the central position of each
set of lines, we were able to extract the corresponding g-factors. However, more studies are
needed to unequivocally assign the sets to the magnetic centers and, thus, here we give the values
without exact assignment. For the set L the values are: ga = 2.24(1), gb = 2.25(1), gc = 2.15(1);
for the set R the values are: ga = 2.19(1), gb = 2.17(1), gc = 2.11(1).
3. CONCLUSIONS
A monomeric phosphoramide complex, Cu(NO3)2([C5H10N]3PO)2, was prepared and
characterized. Single-crystal X-ray diffraction data shows that the Cu2+ central ion has six
oxygen atoms in octahedral coordination with very close axial and equatorial bond lengths. Due
to the large distances between the Cu(II) centers in the monoclinic lattice, the compound is a
paramagnet, with low magnetic anisotropy and magnetic moment in agreement with its
monomeric character, as confirmed by magnetic measurements and EPR studies. Moreover, EPR
spectra give no evidence, at the nanoscale of the probe, for any distortion of the octahedral
geometry around the Cu center.
16

Appendix A. Supplementary data
CCDC 1482823 contains the supplementary crystallographic data for Cu(NO3)2([C5H10N]3PO)2.
These data can be obtained free of charge via http://www.ccdc.cam.ac.uk/conts/retrieving.html,
or from the Cambridge Crystallographic Data Centre, 12 Union Road, Cambridge CB2 1EZ, UK;
fax: (+44) 1223-336-033; or e-mail: deposit@ccdc.cam.ac.uk.
Acknowledgments
The crystallographic part was supported by the Project No. 14-03276S of the Czech Science
Foundation using instruments of the ASTRA laboratory established within the Operation
Program Prague Competitiveness, Project No. CZ.2.16/3.1.00/24510.
We acknowledge the support of HLD at HZDR, member of the European Magnetic Field
Laboratory (EMFL). AS and MP acknowledge the partial support of this work by the Ferdowsi
University of Mashhad
REFERENCES
[1] Upadhyay, L.S.B.; Indian J. Biotech. 2012, 11, 381–388.
[2] Mobley, H.L.T.; Island, M.D.; Hausinger, R.P.; Microbiol. Rev. 1995, 112, 451–480.
17

[3] Akgür, S.A.; Öztürk, P.; Solak, I.; Moral, A.R.; Ege, B.; Forensic Sci. Int. 2003, 133,
136–140.
[4] Pang, Y.-P.; Kollmeyer, T.M.; Hong F.; Lee, J.-C.; Hammond, P.I.; Haugabouk, S.P.;
Brimijoin, S.; Biochem. Biol. 2003, 10, 491–502.
[5] Gholivand, K.; Shariatinia, Z.; Ghadimi, S.; Mojahed, F.; Madani Alizadegan, A.; Khajeh,
K.; Naderimanesh, H.; J. Enzyme Inhib. Med. Chem. 2004, 19,403–407.
[6] Gholivand, K.; Shariatinia, Z.; Oroujzadeh, N.; Heteroatom Chem. 2013, 24, 404–412.
[7] Gholivand, K.; Shariatinia, Z.; Khajeh, K.; Naderimanesh, H.; J. Enzyme Inhib. Med.
Chem. 2006, 21, 31–35.
[8] Gholivand, K.; Abdollahi, M.; Mojahed, F.; MadaniAlizadehgan, A.; Dhghan, G.; J.
Enzyme Inhib. Med. Chem. 2009, 24, 566–576.
[9] Hu, L.; Wu, X.; Han, J.; Chen, L.; Vass, S.O.; Browne, P.; Hall, B.S.; Bot, C.;
Gobalakrishnapillai, V.; Searle, P.F.; Knox, R.J.; Wilkinson, S.R.; Bioorg. Med Chem Lett.
2011, 21, 3986–3991.
[10]Wing, K.D.; Glickman, A.H.; Casida, J.E.; Pestic. Biochem. Physiol. 1984, 21, 22–30.
[11]Miyamoto, T.; Kasagami, T.; Asai, M.; Yamamoto, I.; Pestic. Biochem. Physiol. 1999,
63, 151–162.
[12]Moroz, O.V.; Trush, V.A.; Konovalova, I.S.; Shishkin, O.V.; Moroz, Y.S.; Demeshko,
S.; Amirkhanov, V.M.; Polyhedron 2009, 28, 1331–1335.
18

[13]Shariatinia, Z.; Asadi, E.; Yousefi, M.; Sohrabi, M.; J. Organomet. Chem. 2012, 715, 82–
92.
[14]Gubina, K.E.; Maslov, O.A.; Trush, E.A.; Trush, V.A.; Ovchynnikov, V.A.; Shishkina,
S.V.; Amirkhanov, V. M.; Polyhedron 2009, 28, 2661–2666.
[15]Crawford, M.-J.; Mayer, P.; Noth, H.; Suter, M.; Inorg. Chem.(Comm.) 2004, 43, 6860–
6862.
[16]Denmark, S.E.; Fu, J.; J. Am. Chem. Soc. 2003, 125, 2208–2216.
[17]Cabrera, A.; Salmón, M.; Rosas, N.; Pérez-Flores, J.; Velasco, L.; Espinosa-Pérez, G.;
Arias, J.L.; Polyhedron 1998, 17, 193–197.
[18]Ai, T.; Li, G.; Bioorg. Med. Chem. Lett. 2009, 19, 3967– 3969.
[19]Chen, Z.-X.; Ai, T.; Kaur, P.; Li, G.; Tetrahedron Lett. 2009, 50, 1079–1081.
[20]de Melo, C.V.P.; Vicentini, G.; Castellano, E.E.; Zukerman-Schpector, J.; J. Alloys
Compd. 1995, 225, 350–353.
[21]de Matos, A.P.; Freitas, M.A.; Marshall, A.G.; Marques, N.; Carvalho, A.; Isolani, P.C.;
Vicentini, G.; J. Alloys Compd. 2001, 323-324, 147–149.
[22]da Silva, M.F.P.; Zukerman-Schpector, J.; Vicentini, G.; Isolani, P.C.; Inorg. Chim. Acta
2005, 358, 796–800.
[23]Bukvetskii, B.V.; Mirochnik, A.G.; Zhikhareva, P.A.; Karasev, V.E.; J. Struct. Chem.
2010, 51, 1164–1169.
19

[24]Zhang, J.; Meng, S.; Song, Y.; Yang, J.; Wei, H.; Huang, W.; Cifuentes, M.P.;
Humphrey, M.G.; Zhang, C.; New J. Chem. 2011, 35, 328–338.
[25]Benabicha, F.;Courtois, A.; Delpuech, J.J.; Elka, E.; Hursch, J.; Rodehuser, L.; Rubini,
P.; Polyhedron 1986, 5, 2005–2011.
[26]Gazo, J.; Bersuker, I.B.; Garaj, J.; Kabesowa, M.; Kahout, J.; Langfelderova, H.; Melnik,
M.; Serator, M.; Valach, F.; Coord. Chem. Rev. 1976, 19, 253–297.
[27]Melnik, M.; Coord. Chem. Rev. 1982, 42, 259–293
[28]Corbridge, D.E.C.; Phosphorus an Outline of its Chemistry, Biochemistry and
Technology, 5th ed., Elsevier, Amsterdam, 1995.
[29]Schiemenz, B.; Wessel, T.; Pfirmann, R.; Beck, A.; Europäisches Patent, EP 1 070 724
A1 (2001).
[30]de Aquino, A.R.; Bombieri, G.; Isolani, P.C.; Vicentini, G.; Zukerman-Schpector, J.;
Inorg. Chim. Acta 2000, 306, 102–106.
[31]CrysAlis PRO, Agilent Technologies, Version 1.171.37.31 (2015).
[32]Palatinus, L.; Chapuis, G. ; J. Appl. Cryst. 2007, 40, 786–790.
[33]Petříček, V.; Dušek, M.; Palatinus, L.; Z. Kristallogr. 2014, 229, 345–352.
[34]Zvyagin, S.; Krzystek, J.; van Loosdrecht, P.; Dhalenne, G.; Revcolevschi, A.; Physica
B: Cond. Mat. 2004, 1, 346–347.
[35]Groom, C.R.; Allen, F.H.; Angew. Chem. Int. Ed. 2014, 53, 662–671.
20

[36]Hall, N.; Orio, M.; Gennari, M.; Wills, C.; Molton, F.; Philouze, C.; Jameson, G.B.;
Halcrow, M.A.; Blackman, A.G.; Duboc C.; Inorg. Chem. 2016, 55, 1497–1504.
[37]Buschow, K.H.J.; de Boer, F.R.; Physics of Magnetism and Magnetic Materials, Kluwer
Academic Publishers, 2004.
[38]Abragam, A.; Bleaney, B.; Electron paramagnetic resonance of transition ions, Oxford,
England: Oxford University Press, 1970.
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Synopsis
A copper monomeric phosphoramide complex Cu(NO3)2([C5H10N]3PO)2 was prepared. The Cu2+
are located at an inversion center of the monoclinic lattice and have non-distorted octahedral
coordination. The compound is a paramagnet with very low anisotropy.
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