Synthesis and characterization of cobalt complexes with pentafluorophenylhydrazine: Nucleophilic attack of phenolic oxygen to pentafluorophenyl ring during condensation of two Schiff base ligands

Article abstract of DOI:10.1016/j.jfluchem.2014.01.013

A new dinuclear complex of Co(III), [Co(L^1′)(μ-N ₃)(N₃)]₂ (1) and a mononuclear complex of Co(II) [Co(L²)₂(N₃)₂] (2) were synthesized and characterized by elemental an

Full text of DOI:10.1016/j.jfluchem.2014.01.013

Journal of Fluorine Chemistry 160 (2014) 34–40
Contents lists available at ScienceDirect
Journal of Fluorine Chemistry
journal homepage: www.elsevier.com/locate/fluor
Synthesis and characterization of cobalt complexes with
pentafluorophenylhydrazine: Nucleophilic attack of phenolic oxygen
to pentafluorophenyl ring during condensation of two Schiff base
ligands
a,b
b
a
Nader Noshiranzadeh a, , Rahman Bikas , Katarzyna Slepokura , Mohammad Shaabani ,
´
*
Tadeusz Lis b
a Department of Chemistry, Faculty of Science, University of Zanjan, 45195-313 Zanjan, Iran
b Faculty of Chemistry, University of Wroclaw, Joliot-Curie 14, Wroclaw 50-383, Poland
A R T I C L E I N F O
A B S T R A C T
0
A new dinuclear complex of Co(III), [Co(L1 )(
m-N3)(N3)]2 (1) and a mononuclear complex of Co(II)
Article history:
[Co(L2)2(N3)2] (2) were synthesized and characterized by elemental analyses, spectroscopic methods and
Received 20 December 2013
Received in revised form 16 January 2014
Accepted 18 January 2014
Available online 28 January 2014
0
X-ray diffraction analyses [L2 is (E)-2-(1-(2-(perfluorophenyl)hydrazono)ethyl)pyridine and HL1 is a
ligand which formed by condensation of two molecules of the other Schiff base ligand HL1 = (E)-2-((2-
0
(perfluorophenyl)hydrazono)methyl)phenol]. In complex 1 the final ligand HL1 was formed via
nucleophilic attack of the NH group in one hydrazone to the azomethine moiety in another hydrazone
and the subsequent SNAr reaction of the phenolic oxygen to pentafluorophenyl nucleus giving rise to Ph–
O–Ph structure.
Keywords:
Fluorine remove
Pentafluorophenylhydrazine
Dinuclear complex
Crystal structure
Azide
ß 2014 Elsevier B.V. All rights reserved.
1. Introduction
which may be attributed to the application of fluorine based
materials in crystal engineering [7], biology [8] and material
The chemistry of hydrazine and hydrazone based ligands and
their transition metal complexes is involving a broad research field
such as coordination chemistry, analytical chemistry, biochemistry
and catalysis [1]. These ligands create various environments
similar to biological systems by coordinating through oxygen and
nitrogen atoms. Therefore, they are target molecules for mimicking
the behaviors of several biological systems [2]. It is well known
that the –NH2 group of hydrazines, R–NH–NH2, has a high
reactivity in the condensation reaction with carbonyl group [3].
Moreover, after formation of Schiff base, the intact –NH– moiety
may be involved in the nucleophilic reactions [4]. For example, this
part of hydrazone ligands is able to attack C55O and C55N groups [5]
or may be involved in further Schiff base condensation [6].
On the other hand, the synthesis of new compounds containing
fluorine atom has become an important part of organic chemistry,
science [9]. Pentafluorobenzene derivatives, C6F5X, are highly
reactive compounds toward nucleophilic attack. Various nucleo-
philic reagents (like ROH [10], RSH [11], and RNH2 [12]) replace
fluorine atom(s) in polyfluoroaromatic compounds.
Pentafluorophenylhydrazine (PFPH) is a ditopic compound: (i)
it can act as a precursor for preparing hydrazine based ligands; (ii)
due to the presence of pentafluorophenyl group, it is highly
expected to be a suitable compound for study on reactions
involving carbon-fluorine bond as the reaction site. PFPH has been
successfully employed as reagent for determining low concentra-
tion of carbonyl compounds in the atmosphere [13] and drinking
water [14]. Also, its derivatives have been used for the analysis of
nabumetone and testosterone in human plasma [15]. Neverthe-
less, there is scarce study on coordination capability of PFPH
derivatives and to the best of our knowledge, including search in
the Cambridge Structural Database (CSD) [16], only three metal
complexes with PFPH based ligands have been reported [17]. In
this study, we report synthesis, characterization and crystal
structures of two cobalt complexes of Schiff base ligands derived
from PFPH (Scheme 1).
*
Corresponding author. Tel.: +98 2415152583; fax: +98 2412283202.
E-mail addresses: nadernoshiranzadeh@yahoo.com,
nadernoshiranzadeh@znu.ac.ir (N. Noshiranzadeh).
0022-1139/$ – see front matter ß 2014 Elsevier B.V. All rights reserved.
http://dx.doi.org/10.1016/j.jfluchem.2014.01.013

N. Noshiranzadeh et al. / Journal of Fluorine Chemistry 160 (2014) 34–40
35
Scheme 1. The structures of ligands used in this study.
0
2. Results and discussion
2.2. X-ray structure of [Co(L1 )(
m-N3)(N3)]2 (1)
2.1. Syntheses of complexes and spectroscopy
In order to define the coordination sphere conclusively, a
single-crystal X-ray diffraction study was made. The crystal data
and refinement parameters are presented in Table 1. The structure
of complex 1 with atom numbering scheme is shown in Figs. 1 and
S3 and selected bond lengths and angles are given in Table 2. The
complex is centro-symmetric dimer lying in a special position, on
an inversion center. Single crystal analysis indicates that the
structure of the ligand coordinated to the Co(III) is quite different
from the initially employed ligand. Probably, during the complex-
The reaction of pentafluorophenylhydrazine with salicylal-
dehyde or 2-acethylpyridine in methanol gave the desired Schiff
base ligands (HL1 and L2) with high yield and purity (Scheme 1).
Elemental analyses and NMR spectra of ligands (Figs. S1 and S2)
confirm their proposed structures. In 1H NMR spectrum of HL1 the
singlet peak at
hydrogen. In 1H NMR spectrum of L2 the signal at
is due to CH3 group and the hydrogen of N–H group is located at
9.04 ppm. For HL1, the peaks of N–H and O–H groups are located
at 10.41 and 10.43 ppm, respectively. In both ligands four peaks
between 7 and 8 ppm are due to aromatic hydrogen atoms. In
d
8.34 ppm is due to azomethine (CH55N)
d
2.38 ppm
d
ation, two molecules of Schiff base ligand (HL1) were connected to
0
each other resulting in another ligand (HL1 ). Although this
d
reaction seems to be difficult, similar aggregate of hydrazine
based ligand in the presence of manganese ion has been recently
reported by Tang et al. [21]. Nucleophilic attack of NH group of –
NH–N55C moiety to C55N group and formation of new C55N bond
(through nitrogen atom of –NH–NC and azomethine carbon) has
been earlier reported by Mu¨ller et al., too [22]. In the present study,
during the complexation the N–H moiety of one ligand attacks to
the azomethine carbon atom of the second one, and consequently
one H2 molecule removes to form another C55N group by this
condensation (Scheme 2). During this reaction, the nucleophilic
attack of phenolic oxygen of salicylidine group to the neighbored
fluorine atom on pentafluorobenzene ring excretes fluoride anion
and Ph–O–Ph group together with seven-membered ring form
d
13C NMR spectrum of ligands the signals of carbon atoms of
pentaflouorophenyl ring appear as seven multiplet peaks (due to
C–F coupling). In fact, six multiplet peaks are related to three
types of carbon atoms directly connected to F atoms (see Figs. S1
and S2). The peaks of these three carbon atoms split to doublet
1
peaks by JCF ꢀ 250 Hz. The remaining multiplet peak
(d
121.4 ppm in HL1 and
d
122.1 ppm in L2) is related to carbon
atom of pentaflouorophenyl ring connected to –NH– group
0
3
(splited by JCF). Complexes [Co(L1 )(
m-N3)(N3)]2 (1) and
[Co(L2)2(N3)2] (2) were synthesized by the reaction of ligands,
CoSO4ꢁ7H2O and NaN3 with molar ratios of 1.0:1.0:2.0 in
methanol. It was found that the structure of HL1 is changed
(Fig. 2). The proposed mechanism of this reaction and formation of
0
0
during the complexation and another ligand (L1 ) is formed by
HL1 is shown in Scheme 2.
coupling of two HL1 ligands. Spectroscopic data confirm that the
In 1, the environment of cobalt atom is a six-coordinated
structure as a CoON5 with oxygen and two nitrogen atoms
provided by the Schiff base ligand, a nitrogen atom from terminal
0
HL1 is not formed by direct reaction of salicylaldehyde and
pentafluorophenylhydrazine. In the IR spectrum of complex 1,
two very strong bands at 2067 and 2007 cmꢂ1 are due to presence
of two different EO-bridged and terminal azide ligands [18]. In
azide ligand and two nitrogen atoms from two
m1,1-azide bridging
groups. The overall geometry around cobalt(III) ion in complex 1 is
best described as a distorted octahedral. Two cobalt(III) cations are
linked by two end-on bridging azide groups giving rise to four-
membered Co2N2 cyclic unit. In 1, the Schiff base ligand forms
equatorial plane together with the nitrogen atom from the
inversion-related azide bridging ligand. The axial positions
are occupied by the nitrogen atoms from two azide ligands: one
terminal and one bridging N3ꢂ. Thus, each bridging azide is the
complex 2 the stretching vibration of the azide group,
n(N3),
appears at 2064 cm–1. The absorption bands at 1605 (1) and
1600 cmꢂ1 (2), can be assigned to the imine C55N stretching
frequency of the coordinated ligands [19]. In both 1 and 2, the
broad peak at about 3400 cmꢂ1 is due to N–H group of
coordinated ligands and indicates they are involved in hydrogen
bonding [20].

36
N. Noshiranzadeh et al. / Journal of Fluorine Chemistry 160 (2014) 34–40
Table 1
Table 2
Crystallographic data of 1 and 2.
Selected bond lengths and bond angles of complexes 1 and 2.
1
2
Complex 1
Complex 2
Formula
C52H20Co2F18N20O4
1448.74
C26H16CoF10N12
745.44
Co1–N1
1.879(3)
1.903(2)
Co1–N1
2.113(2)
2.228(2)
2.074(2)
93.80(12)
96.08(8)
91.42(8)
169.02(12)
167.61(8)
94.25(8)
74.33(8)
97.06(7)
79.47(10)
Mr (g molꢂ1
)
Co1–O1
Co1–N2
Crystal size (mm)
Crystal shape, color
T (K)
0.37 ꢃ 0.07 ꢃ 0.07
Needle, black
100(2)
0.17 ꢃ 0.10 ꢃ 0.07
Block, dark pink
100(2)
Co1–N3
1.919(3)
Co1–N4
Co1–N8
Co1–N5i
1.950(3)
N4–Co1–N4i
N4–Co1–N1i
N4–Co1–N1
N1i–Co1–N1
N4–Co1–N2i
N4–Co1–N2
N1–Co1–N2
N1–Co1–N2i
N2–Co1–N2i
1.976(3)
˚
˚
Radiation
MoK
(
l
= 0.71073 A)
MoK
(l
a
= 0.71073 A)
Co1–N5
2.011(3)
a
Crystal system, space group
Monoclinic, P21/n
10.656(4)
16.671(6)
16.249(7)
108.04(5)
2745(2)
2
Monoclinic, C2/c
14.048(4)
8.806(3)
22.688(7)
91.23(3)
2806.0(15)
4
N1–Co1–O1
N1–Co1–N3
O1–Co1–N3
N1–Co1–N8
O1–Co1–N8
N3–Co1–N8
N1–Co1–N5i
O1–Co1–N5i
N3–Co1–N5i
N8–Co1–N5i
N1–Co1–N5
O1–Co1–N5
N3–Co1–N5
N8–Co1–N5
N5–Co1–N5i
94.08(11)
82.19(12)
176.26(10)
91.06(11)
92.95(11)
87.31(11)
172.22(11)
90.23(10)
93.46(11)
95.20(11)
95.91(10)
88.19(9)
˚
a (A)
˚
b (A)
˚
c (A)
b
(8)
˚
3
V (A )
Z
Calc. density (g cmꢂ3
)
1.753
1.765
F(000)
1440
1492
m
(mmꢂ1
)
0.73
0.72
Absorption correction
Tmin/Tmax
Analytical
0.858/0.964
25,021
Analytical
0.907/0.957
9885
Measured reflections
h, k, l
92.02(10)
172.84(11)
77.72(11)
ꢂ14!14
ꢂ22!20
ꢂ21!19
2.9–28.1
6565
ꢂ18!18
ꢂ11!10
ꢂ30!28
2.9–28.8
3408
Symmetry code (i) for complex 1 = ꢂx + 1, ꢂy + 1, ꢂz + 1, for complex 2 =ꢂx + 1, y,
ꢂz + 3/2.
Q
range
Independent reflections
Observed reflections
Rint
3137
2043
0.116
0.071
[23]. Both terminal and end-on azide ligands show asymmetric N–
N distances (N5–N6/N6–N7) of 1.237(3)/1.155(3) A in bridge azide
and 1.214(4)/1.156(4) A (N8–N9/N9–N10) in terminal azide,
Data/parameters/restraints
6565/437/0
0.054a
0.062a
3408/227/0
0.049a
0.060a
˚
R1(Fobs
)
˚
wR2 (Fa2ll
)
which are in the normal range.
GooF = S
0.97
1.00
Shift/errormax
0.001
0.001
The structure of the complex 1 is additionally stabilized by two
centrosymmetric intramolecular N–Hꢁ ꢁ ꢁO hydrogen bonds in
which the oxygen atoms of phenolate groups act as hydrogen
bond acceptors. The additional stabilization of the crystal lattice is
provided by weak C–Hꢁ ꢁ ꢁF [24] and C–Hꢁ ꢁ ꢁN contacts (Table 3), as
ꢂ3
˚
Drmax/Drmin (e A
)
0.46/ ꢂ 0.45
0.42/ ꢂ 0.52
qffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffi
P
P
P
P
2
2
a
R1 ¼ jjFoj ꢂ jFcjj= jFoj; wR2 ¼
½wðFo2 ꢂ Fc2Þ ꢄ= ½wðFo2Þ ꢄ; detailed in-
formation on the weighting scheme (w) is given in the crystallographic information
files (CIFs).
well as by the Fꢁ ꢁ ꢁ
p
[the shortest Fꢁ ꢁ ꢁcentroid distances are
˚
axial ligand of one Co(III) center and the basal ligand of the another
Co(III). The distances between cobalt atom and the axial nitrogen
3.432(3) and 3.476(3) A] and two Fꢁ ꢁ ꢁF interactions (2.901(3),
˚
2.946(3) A; Fig. S4) [25].
˚
atoms are 2.011(3) (Co1–N5) and 1.950(3) A (Co1–N8). In this
dimeric unit the Coꢁ ꢁ ꢁCo distance within the four-membered
2.3. X-ray structure of [Co(L2)2(N3)2]
˚
Co2N2 cyclic units is 3.104(2) A and the four-membered Co2(m1,1
-
N3)2 cyclic unit is planar, which is characteristic of the double end-
on bridges. Within the Co2N2 cycle the N–Co–N and Co–N–Co bond
angles are respectively 77.72(11)8 and 102.28(11)8. The N–N–N
angle is 177.1(3)8 for bridging and 175.3(3)8 for terminal azides
The crystal structure of complex [Co(L2)2(N3)2], has also been
determined by X-ray crystallography. A plot of the monomeric unit
is shown in Figs. 3 and S5 and selected bond lengths and angles are
listed in Table 2. The structural analysis revealed that the crystal of
Fig. 1. Molecular structure of centrosymmetric complex 1 showing the N–Hꢁ ꢁ ꢁO
hydrogen bonds (dashed lines). The symmetry-related ligand anions are indicated
in different colors: light orange – ligands with x, y, z; black – ligands with ꢂx + 1,
ꢂy + 1, ꢂz + 1 [symmetry code (i)]. (For interpretation of the references to color in
this figure legend, the reader is referred to the web version of the article.)
Fig. 2. The X-ray structure of the ligand anion observed in complex 1, showing its
conformation and atom-numbering scheme.

N. Noshiranzadeh et al. / Journal of Fluorine Chemistry 160 (2014) 34–40
37
0
Scheme 2. Proposed mechanism for the formation of HL1 from HL1 in the presence of CoSO4ꢁ7H2O.
Fig. 3. Molecular structure of complex 2 showing the
p p interactions (dashed lines). The symmetry-related ligand anions are indicated in different colors: light orange –
ꢁ ꢁ ꢁ
ligands with x, y, z; black – ligands with ꢂx + 1, y, ꢂz + 3/2 [symmetry code (i)]. (For interpretation of the references to color in this figure legend, the reader is referred to the
web version of the article.)
2 is built up from neutral mono-nuclear complexes of Co(II) in
Table 3
˚
which cobalt atom lies in a special position, on a two-fold axis, and
is six-coordinated, as a cis-[Co(N2L)2(NAzide)2], with four nitrogen
atoms (N1, N1i, N2 and N2i) provided by two Schiff base ligands,
and two nitrogen atoms (N4 and N4i) from two terminal azide
ligands. The overall geometry around Co(II) ion in complex 2 is best
described as a slightly distorted octahedral. The Co–N distances are
in normal range and are close to other Co(II) complexes reported in
the literature [26]. The azide ligands show asymmetric N–N
Hydrogen-bond geometry (A,8) in complexes 1 and 2.
D–Hꢁ ꢁ ꢁA
D–H
Hꢁ ꢁ ꢁA
Dꢁ ꢁ ꢁA
D–Hꢁ ꢁ ꢁA
Complex 1
N4–H4Nꢁ ꢁ ꢁO1i
C14–H14ꢁ ꢁ ꢁF2ii
C18–H18ꢁ ꢁ ꢁN7iii
C20–H20ꢁ ꢁ ꢁF3iv
Complex 2
0.90(3)
0.95
2.01(3)
2.55
2.849(3)
3.249(4)
3.332(5)
3.326(4)
155(3)
130
0.95
2.58
137
0.95
2.55
139
N3–H3Nꢁ ꢁ ꢁN6i
C9–H9ꢁ ꢁ ꢁN4ii
C10–H10ꢁ ꢁ ꢁF2iii
C13–H13Bꢁ ꢁ ꢁN4ii
0.88(2)
0.95
1.98(2)
2.58
2.853 (3)
3.267 (3)
3.270 (3)
3.535 (3)
172(2)
129
˚
distances (N4–N5/N5–N6) of 1.195(3)/1.168(3) A and the N4–N5–
N6 angle is 178.7(3)8.
0.95
2.46
143
The structure of complex 2 is supported by the
p p stacking
ꢁ ꢁ ꢁ
0.98
2.59
161
˚
interactions [27] with centroid separation of 3.647(2) A, as shown
in Fig. 3. The intermolecular N–Hꢁ ꢁ ꢁN hydrogen bonds, involving
the azide nitrogen atom as an acceptor, link the molecules into a
Symmetry codes for complex 1: (i) ꢂx + 1, ꢂy + 1, ꢂz + 1; (ii) ꢂx + 3/2, y + 1/2, ꢂz + 3/
2; (iii) x + 1, y, z; (iv) x + 1/2, ꢂy +1/2, z + 1/2. Symmetry codes for complex 2: (i) x,
y ꢂ 1, z; (ii) ꢂx + 1/2, y ꢂ 1/2, ꢂz + 3/2; (iii) x ꢂ 1/2, ꢂy + 3/2, z + 1/2.

38
N. Noshiranzadeh et al. / Journal of Fluorine Chemistry 160 (2014) 34–40
Fig. 4. Chains of complex molecules in 2 running along the b-axis, resulting from N–Hꢁ ꢁ ꢁN hydrogen bonds (dashed lines). Viewed down the a-axis. Symmetry code is given in
Table 3.
one-dimensional polymeric chains running down the b-axis
(Fig. 4). The inter-chain contacts and additional stabilization of
the crystal lattice are provided by weak C–Hꢁ ꢁ ꢁN and C–Hꢁ ꢁ ꢁF
bath to 5 mL and cooled to room temperature. Resulting light
yellow precipitate was separated and filtered off, washed with
5 mL of methanol and recrystallized from ethanol. Yield: 0.530 g
(88%). M.p. 213–214.5 8C. Anal. Calc. for C13H7F5N2O
(MW = 302.20): C, 51.67; H, 2.33; N, 9.27%. Found: C, 51.68; H,
2.31; N, 9.30%. Selected FT–IR (KBr, cmꢂ1): 3440 (m, br), 3304 (vs),
1659 (m), 1621 (s), 1601 (s), 1570 (m), 1545 (s), 1531 (vs), 1502
(vs), 1459 (m), 1307 (m), 1264 (vs), 1218 (m), 1202 (m), 1169 (s),
1130 (vs), 1104 (s), 1023 (vs), 972 (vs), 950 (s), 801 (s), 786 (vs),
760 (vs), 671 (s), 575 (s). 1H NMR (500 MHz, DMSO-d6, TMS):
(Table 3) [24], as well as by the C–Hꢁ ꢁ ꢁ
p
[28] (with the Hꢁ ꢁ ꢁcentroid
˚
distance amounting to 2.70 A), and Fꢁ ꢁ ꢁ
p interactions (the shortest
˚
Fꢁ ꢁ ꢁcentroid distance of 3.361(2) A) [29].
3. Conclusion
Two new complexes of cobalt with Schiff base ligands based on
pentafluorophenylhydrazine and azide ligands were synthesized
and characterized by elemental analyses, spectroscopic methods
and X-ray diffraction analyses. The final ligand observed in
complex 1 results from the condensation of two Schiff base
molecules. Our proposed mechanism of this reaction involves the
necleophilic attack of NH group of one ligand to azomethine
moiety of the other, and the subsequent nucleophilic attack of
phenolic oxygen of the latter to pentafluorophenyl ring of the
former, giving rise to formation of Ph–O–Ph group and seven
membered C/O/C/C/N/C/C ring.
3
4
d
= 6.89 (m, 2H), 7.22 (dt, 1H, JHH = 7.67 Hz, JHH = 1.62 Hz), 7.44
(d, 1H, 3JHH = 7.75 Hz), 8.37 (s, 1H, CH55N), 10.41 (s, 1H, NH), 10.44
(s, 1H, OH). 13C NMR (126 MHz, DMSO-d6):
= 116.6, 119.8, 119.9,
d
128.8, 130.7, 143.7, 156.8 (7 atom of salcylidine part), 121.4 (m,
Ca), 133.1 and 135.0 (dm, 1JCF = 243.6 Hz, Cd), 136.5 and 138.3 (dm,
1JCF = 235.3 Hz, Cc), 137.3 and 139.3 (dm, 1JCF = 245.4 Hz, Cb) ppm.
4.3. Synthesis of (E)-2-(1-(2-
(perfluorophenyl)hydrazono)ethyl)pyridine (L2)
A methanol (10 mL) solution of 2-acetylpyridine (0.242 g,
2 mmol) was drop-wise added to a methanol solution (10 mL)
of pentafluorophenylhydrazine (0.396 g, 2 mmol) and the mixture
was refluxed for 4 h. Then, the solution was evaporated on a steam
bath to 5 mL and cooled to room temperature. Resulting white
precipitate was separated and filtered off, washed with 5 mL of
methanol and recrystallized from ethanol. Yield: 0.548 g (91%).
M.p. 107.5–109 8C. Anal. Calc. for C13H8F5N3 (MW = 301.21): C,
51.84; H, 2.68; N, 13.95%. Found: C, 51.79; H, 2.66; N, 13.99%.
Selected FT–IR (KBr, cmꢂ1): 3313 (s, br), 1660 (s), 1607 (m), 1541
(vs), 1529 (vs), 1491 (s), 1471 (s), 1456 (m), 1435 (s), 1293 (s), 1177
(vs), 1156 (s), 1137 (s), 1105 (s), 1081 (vs), 1030 (vs), 991 (s), 952
(s), 785 (vs), 695 (m), 562 (m). 1H NMR (500 MHz, DMSO-d6, TMS):
4. Experimental
4.1. Materials and instrumentations
Cobalt(II) sulfate heptahydrate, pentafluorophenylhydrazine, 2-
acethylpyridine, salicylaldehyde and sodium azide were purchased
from Merck and used as received. Solvents of the highest grade
commercially available (Merck) were used without further purifi-
cation. FT–IR spectra were recorded as KBr disks with a Bruker FT–IR
spectrophotometer. 1H and 13C NMR spectra of ligands in DMSO-d6
solution were recorded on a Bruker 500 MHz spectrometer and
chemical shifts are indicated in ppm relative to tetramethylsilane.
The elemental analyses (carbon, hydrogen and nitrogen) of the
compounds were obtained from a Carlo ERBA Model EA 1108
analyzer. The cobalt content of the complexes was measured by
atomic absorption on a Varian AAS-110 spectrometer.
d
= 2.38 (s, 3H, CH3), 7.32 (1H, dt, 3JHH = 6.3 Hz, 4JHH = 1.25 Hz), 7.77
(1H, dt, 3JHH = 8.37 Hz, 4JHH = 1.05 Hz), 7.93 (1H, d, 3JHH = 8.05 Hz),
3
8.56 (1H, d, JHH = 4.8 Hz), 9.04 (s, 1H, NH). 13C NMR (126 MHz,
DMSO-d6):
d = 11.6 (CH3), 119.8, 123.6, 136.8, 148.2, 148.9, 155.7,
122.1 (m, Ca), 134.7 and 136.7 (dm, JCF ꢀ 254 Hz, Cd), 137.1 and
139.1 (dm, 1JCF = 249.1 Hz, Cc), 138.6 and 140.5 (dm,
1JCF = 246.2 Hz, Cb) ppm.
1
4.2. Synthesis of (E)-2-((2-
(perfluorophenyl)hydrazono)methyl)phenol (HL1)
0
A
methanol (10 mL) solution of salicylaldehyde (0.244 g,
4.4. Synthesis of [Co(L1 )(
m
-N3)(N3)]2 (1)
2 mmol) was dropwise added to a methanol solution (10 mL) of
pentafluorophenylhydrazine (0.396 g, 2 mmol) and the mixture
was refluxed for 4 h. Then, the solution was evaporated on a steam
This complex was synthesized by the reaction of Schiff base
ligand, HL1, (0.302 g, 1.0 mmol), CoSO4ꢁ7H2O (0.281 g, 1.0 mmol)

N. Noshiranzadeh et al. / Journal of Fluorine Chemistry 160 (2014) 34–40
39
and sodium azide (0.13 g, 2.0 mmol) using the thermal gradient
Appendix A. Supplementary data
method in a branched tube and methanol used as solvent. For this
propose, mentioned amount of materials were placed in the main
arm of a branched tube. Methanol was carefully added to fill the
arms, the tube was sealed and the reagents containing arm
immersed in an oil bath at 60 8C while the other arm was kept at
ambient temperature. After a week, black crystals were deposited
in the cooler arm, which were filtered off and air dried. Caution!
Although we have not experienced any problem with the reported
compound in this work, azide complexes of metal ions are potentially
explosive. Only a small amount of a product should be prepared, and it
should be handled with care. Yield: 0.21 g (58% based on HL1). Anal.
Calc. for C52H20Co2F18N20O4 (MW = 1448.74): C, 43.11; H, 1.39; N,
19.34; Co, 8.14%. Found: C, 43.07; H, 1.37; N, 19.39; Co, 8.16%. FT–
IR (KBr, cmꢂ1): 3450 (m, br), 2067 (vs, N3ꢂ), 2007 (vs, N3ꢂ), 1605
(s), 1587 (s), 1512 (vs), 1384 (m), 1361 (s), 1263 (m), 1204 (m),
1088 (vs), 1026 (s), 1003 (m), 980 (m), 961 (s), 889 (m), 772 (m),
755 (s), 743 (m), 598 (m), 570 (m).
Supplementary material related to this article can be found,
in the online version, at http://dx.doi.org/10.1016/j.jfluchem.
2014.01.013.
References
[1] (a) S.I. Orysyk, V.V. Bon, O.O. Zholob, V.I. Pekhnyo, V.V. Orysyk, Y.L. Zborovskii,
M.V. Vovk, Polyhedron 51 (2013) 211–221;
(b) H. Hosseini Monfared, R. Bikas, P. Mayer, Inorg. Chim. Acta 363 (2010) 2574–
2583;
´ ˜
(c) S. Distinto, M. Yanez, S. Alcaro, M.C. Cardia, M. Gaspari, M.L. Sanna, R. Meleddu,
F. Ortuso, J. Kirchmair, P. Markt, A. Bolasco, G. Wolber, D. Secci, E. Maccioni, Eur. J.
Med. Chem. 48 (2012) 284–295;
(d) M. Ghorbanloo, H. Hosseini-Monfared, C. Janiak, J. Mol. Catal. A: Chem. 345
(2011) 12–20;
(e) R. Bikas, H. Hosseini-Monfared, G. Zoppellaro, R. Herchel, J. Tucek, A.M.
Owczarzak, M. Kubicki, R. Zboril, Dalton Trans. 42 (2013) 2803–2812;
(f) H. Hosseini Monfared, Z. Kalantari, M.-A. Kamyabi, C. Janiak, Z. Anorg. Allg.
Chem. 633 (2007) 1945–1948;
(g) H. Hosseini-Monfared, N. Asghari-Lalami, A. Pazio, K. Wozniak, C. Janiak,
Inorg. Chim. Acta 406 (2013) 241–250;
4.5. Synthesis of [Co(L2)2(N3)2] (2)
(h) H. Hosseini-Monfared, M. Vahedpour, M. Mahdavi Yeganeh, M. Ghorbanloo, P.
Mayer, C. Janiak, Dalton Trans. 40 (2011) 1286–1294.
[2] (a) P. Krishnamoorthy, P. Sathyadevi, P.T. Muthiah, N. Dharmaraj, RSC Adv. 2
(2012) 12190–12203;
(b) M. Alagesan, N.S.P. Bhuvanesh, N. Dharmaraj, Dalton Trans. 42 (2013) 7210–
7223.
[3] M.E. Belowich, J.F. Stoddart, Chem. Soc. Rev. 41 (2012) 2003–2024.
[4] I.M. Muller, S. Spillmann, H. Franck, R. Pietschnig, Chem. Eur. J. 10 (2004) 2207–
2213.
[5] X. Li, A.S. Hay, Macromolecules 39 (2006) 3714–3716.
[6] (a) L.-P. Song, S.-Z. Zhu, J. Fluorine Chem. 111 (2001) 201–205;
(b) F.A. Bagrov, D.F. Bagrov, Zh. Org. Khim. 29 (1993) 3–2260.
[7] D. Chopra, T.N.G. Row, CrystEngComm 13 (2011) 2175–2186.
[8] (a) F. Menaa, B. Menaa, O. Sharts, Faraday Discuss. 149 (2011) 269–278;
(b) H. Chen, S. Viel, F. Ziarelli, L. Peng, Chem. Soc. Rev. 42 (2013) 7971–7982.
[9] (a) R. Berger, G. Resnati, P. Metrangolo, E. Weber, J. Hulliger, Chem. Soc. Rev. 40
(2011) 3496–3508;
Single crystals of complex 2 were obtained following the same
procedure as for complex 1, using CoSO4.7H2O (0.281 g, 1.0 mmol),
NaN3 (0.13 g, 2.0 mmol) and hydrazine ligand, L2, (0.301 g,
1.0 mmol) in a branched tube and methanol was used as solvent.
After four days, the obtained dark pink crystals were filtered off
and air dried. Yield: 75% (0.56 g). Anal. Calc. for C26H16CoF10N12
(MW = 745.44): C, 41.89; H, 2.16; N, 22.55; Co, 7.91%. Found: C,
41.85; H, 2.15; N, 22.61; Co, 7.97%. FT–IR (KBr, cmꢂ1): 3430 (s, br),
3187 (m), 2924 (m), 2853 (m), 2064 (vs, N3ꢂ), 1634 (m), 1600 (m),
1521 (vs), 1475 (m), 1438 (w), 1385 (s), 1165 (m), 1084 (m), 1011
(m), 996 (m), 965 (m), 810 (w), 789 (m), 758 (m), 693 (w), 566 (m),
480 (m), 444 (m), 419 (m).
(b) E.A. Meyer, R.K. Castellano, F. Diederich, Angew. Chem. Int. Ed. 42 (2003)
1210–1250.
[10] (a) B. Doherty, M. Nieuwenhuyzen, G.C. Saunders, M.S. Sloan, J. Fluorine Chem.
119 (2003) 15–19;
4.6. X-ray crystallography
(b) N.Y. Adonin, V.V. Bardin, J. Fluorine Chem. 153 (2013) 165–167;
(c) C.L. Allaway, M. Daly, M. Nieuwenhuyzen, G.C. Saunders, J. Fluorine Chem. 115
(2002) 91–99.
X-ray diffraction data for 1 and 2 were collected at 100 K by the
-scan technique on Kuma KM4 CCD diffractometers with a
v
[11] C. Yu, G. Hu, C. Zhang, R. Wu, H. Ye, G. Yang, X. Shi, J. Fluorine Chem. 153 (2013)
33–38.
[12] R.D. Chambers, P.A. Martin, G. Sandford, D.L.H. Williams, J. Fluorine Chem. 129
(2008) 998–1002.
Sapphire 2 CCD detector using graphite-monochromatized MoK
˚
a
radiation (
l
= 0.71073 A). Data were corrected for Lorentz and
polarization effects. Data collection, cell refinement, and data
reduction and analysis were carried out with CrysAlisCCD and
CrysAlisRED, respectively [30]. Analytical absorption correction
was applied to the data with the use of CrysAlisRED [30]. The
structures were solved by direct methods using SHELXS-97 [31],
and refined by a full-matrix least squares technique on F2 with
SHELXL-2013 with anisotropic thermal parameters for all non-H
atoms [31]. All H atoms were found in difference Fourier maps, and
in the final refinement cycles the C-bonded H atoms were
repositioned in their calculated positions and refined using a
[13] (a) X. Pang, A.C. Lewis, J.F. Hamilton, Talanta 85 (2011) 406–414;
(b) Y. Feng, C. Mu, J. Zhai, J. Li, T. Zou, J. Hazard. Mater. 183 (2010) 574–582;
(c) C. Xie, P. Xie, J. Li, L. Yan, Adv. Mater. Res. 610–613 (2013) 36–39.
[14] N.R. Neng, J.M.F. Nogueira, Anal. Bioanal. Chem. 398 (2010) 3155–3163.
[15] J.F. Sheen, G.R. Her, Anal. Bioanal. Chem. 380 (2004) 891–897.
[16] F.H. Allen, Acta Cryt. B58 (2002) 380–388.
[17] (a) Z. Ding, S. Xia, X. Ji, H. Yang, F. Tao, Q. Wang, Synthesis (2002) 349–354;
(b) B.-W. Sun, M.-S. Zhang, G.-Y. Yang, S.G. Ang, H.G. Ang, Acta Cryst. E61 (2005)
m2419–m2420;
(c) X. Liu, Q. Wang, Y. Liu, Y. Fan, Z. Ding, Synthesis (2000) 435–441.
[18] (a) H. Hosseini-Monfared, R. Bikas, J. Sanchiz, T. Lis, M. Siczek, J. Tucek, R. Zboril, P.
Mayer, Polyhedron 61 (2013) 45–55;
(b) H. Hosseini-Monfared, R. Bikas, M. Siczek, T. Lis, R. Szymczak, P. Aleshkevych,
Inorg. Chem. Commun. 35 (2013) 172–175.
˚
riding model, with C–H = 0.95–0.98 A, and with Uiso(H) = 1.2Ueq(C)
for CH or 1.5Ueq(C) for CH3. The structure plots for complexes 1 and
2 were prepared with DIAMOND [32].
[19] (a) G. Kolawole, K.S. Patel, J. Chem. Soc. Dalton Trans. (1981) 1241–1245;
(b) H. Hosseini-Monfared, R. Bikas, P. Mahboubi-Anarjan, A.J. Blake, V. Lippolis,
N.B. Arslan, C. Kazak, Polyhedron 69 (2014) 90–102;
Crystallographic data (excluding structure factors) for the
structural analyses have been deposited with the Cambridge
Crystallographic Data Centre, No. 971391 and 971392 for 1 and 2,
respectively. Copies of this information may be obtained free of
charge from: The Director, CCDC, 12 Union Road, Cambridge, CB2
1EZ, UK. Fax: +44 1223 336 033, deposit@ccdc.cam.ac.uk, or www:
www.ccdc.cam.ac.uk.
(c) R. Bikas, H. Hosseini-Monfared, L. Sieron´ , A. Gutie´rrezc, J. Coord. Chem. 66
(2013) 4023–4031.
[20] (a) J.G. Małecki, J. Mrozinski, K. Michalik, Polyhedron 30 (2011) 1806–1814;
(b) Y.-Z. Lin, J.-G. Wu, G.-X. Xu, Microchim. Acta 94 (1988) 219–221.
[21] J. Tang, S. Nayak, J.S. Costa, A. Robertazzi, R. Pievo, I. Mutikainen, O. Roubeau, S.J.
Teat, P. Gamez, J. Reedijk, Dalton Trans. 39 (2010) 1361–1365.
[22] I.M. Mu¨ller, S. Spillmann, H. Franck, R. Pietschnig, Chem. Eur. J. 10 (2004) 2207–
2213.
[23] (a) R. Bikas, H. Hosseini-Monfared, T. Lis, M. Siczek, Inorg. Chem. Commun. 15
(2012) 151–155;
Acknowledgments
(b) R. Bikas, H. Hosseini-Monfared, M. Siczek, A. Gutie´rrez, M.S. Krawczyk, T. Lis,
Polyhedron 67 (2014) 396–404.
[24] (a) N. Lu, W.-H. Tu, Y.-S. Wen, L.-K. Liu, C.-Y. Chou, J.-C. Jiang, CrystEngComm 12
(2010) 538–542;
We acknowledge the University of Zanjan for funding this
research work. R. Bikas thanks to the Ministry of Science, Research
and Technology of the I.R. Iran for fellowship No. 213631.
(b) D.G. Golovanov, K.A. Lyssenko, M.Y. Antipin, Y.S. Vygodskii, E.I. Lozinskaya,
A.S. Shaplov, CrystEngComm 7 (2005) 53–56;

40
N. Noshiranzadeh et al. / Journal of Fluorine Chemistry 160 (2014) 34–40
(c) J. Ruiz, V. Rodrı´guez, C. Haro, A. Espinosa, J. Pe´rez, C. Janiak, Dalton Trans. 39
(2010) 3290–3301.
(b) M. Mirzaei, H. Eshtiagh-Hosseini, M. Chahkandi, N. Alfi, A. Shokrollahi, N.
Shokrollahi, A. Janiak, CrystEngComm 14 (2012) 8468–8484;
[25] M.S. Pavan, K.D. Prasad, T.N.G. Row, Chem. Commun. 49 (2013) 7558–7560.
[26] C.M. Araujo, M.D. Doherty, S.J. Konezny, O.R. Luca, A. Usyatinsky, H. Grade, E.
Lobkovsky, G.L. Soloveichik, R.H. Crabtree, V.S. Batista, Dalton Trans. 41 (2012)
3562–3573.
[27] G.S. Hair, A.H. Cowley, J.D. Gorden, J.N. Jones, R.A. Jones, C.L.B. Macdonald, Chem.
Commun. (2003) 424–425.
(c) M. Nishio, Phys. Chem. Chem. Phys. 14 (2011) 13873–13900;
(d) C. Janiak, S. Temizdemir, S. Dechert, W. Deck, F. Girgsdies, J. Heinze, M.J. Kolm,
T.G. Scharmann, O.M. Zipffel, Eur. J. Inorg. Chem. (2000) 1229–1241.
[29] N. Hayashi, T. Mori, K. Matsumoto, Chem. Commun. (1998) 1905–1906.
[30] Oxford Diffraction CrysAlisCCD and CrysAlisRED in Kuma KM4ꢂCCD software,
Oxford Diffraction Ltd., Yarnton, Oxfordshire, England, 2009.
[28] (a) X.-J. Yang, F. Drepper, B. Wu, W.-H. Sun, W. Haehnel, C. Janiak, Dalton Trans.
(2005) 256–267;
[31] G.M. Sheldrick, Acta Cryst A64 (2008) 112–122.
[32] K. Brandenburg, DIAMOND, Crystal Impact GbR, Bonn, Germany, 2005.