Crystal Structure Theory and Applications, 2012, 1, 1-8
http://dx.doi.org/10.4236/csta.2012.11001 Published Online June 2012 (http://www.SciRP.org/journal/csta)
Crystal and Molecular Structure of
4-Benzoyl-1,5-diphenyl-1H-pyrazole-3-carbonitrile
E. Korkusuz1, E. Şahin2, İ. Yildirim3*
1Kayseri Vocational Colage, Erciyes University, Kayseri, Turkey
2Department of Chemistry, Faculty of Sciences, Atatürk University, Erzurum, Turkey
3Department of Chemistry, Faculty of Sciences, Erciyes University, Kayseri, Turkey
Received April 5, 2012; revised May 22, 2012; accepted June 11, 2012
ABSTRACT
The crystal structure of potential active 4-benzoyl-1,5-diphenyl-1H-pyrazole-3-carbonitrile (C23H15N3O) (I) has been
determined from single crystal X-ray diffraction data. Also IR, Uv-vis and NMR spectral data were determined. The
title compound crystallizes in the monoclinic space group P 21/c, with a = 9.3167(2), b = 20.6677(3), c = 10.6143(3) Å,
β = 112.665(3)˚, V = 1886.00(8) Å3, Dcalc = 1.23g cm–3, Z = 4. In the structure, intermolecular H-bonds lead to the for-
mation of a centrosymmetric dimmer of the molecule. Furthermore, the compound has a wide transmission window
(300 to 1100 nm) with a transparency of nearly 100% and the UV cut-off wavelength occurs at 242 nm.
Keywords: Pyrazole-3-Carbonitrile; 2,3-Furandione; Single Crystal Structure; X-Ray Diffraction; IR; NMR Spectra
1. Introduction
Pyrazole nucleus and its derivatives such as nitriles, am-
ides or esters possess numerous chemical, biological,
medicinal, and agricultural applications due to their ver-
satile biological activities appearing as antimicrobial
[1,2], antiviral [3,4], antibacterial [5], antitumor [6-8],
anti-inflammatory [9,10], antihistaminic [11], pesticidal
[12,13], antifungal [14], against rheumatoid arthritis [15],
anticonvulsant [16], antidepressant [17], antipyretic [18],
and commercially important dyestuffs [19] agents. Their
excellent control activities on various plant diseases are
studied, too [20,21]. Recently, reactions of cyclic oxalyl
compounds have been reported to give substituted het-
erocyclic compounds [22-26]. The reaction of 4-benzoyl-
5-phenylfuran-2,3-dione, obtained easily from dibenzoyl-
methane and oxalyl dichloride [22], with various phenyl
hydrazones and phenylhydrazine leads to pyrazole car-
boxylic acids and pyridazinones [27-29]. Nitriles are
widely used for transformation into amides, amines, es-
ters, carboxylic acids etc. [30]. Hence they have been
used as intermediates for the synthesis of fine chemicals
such as agricultural chemicals, dyes and medicines [31].
Title compound was mainly synthesized from 4-benzoyl-
1,5-diphenyl-1H-pyrazole-3-carboxylic acid together with-
acid chloride and its amide derivatives (Scheme 1). Fur-
thermore, a cold solution of the acid amide in a mixture
of Dimethyl formamide (DMF) and Thionylchloride
(SOCl2) was stirred at 0˚C - 5˚C for 2 hours to give the
nitrile product. In view of these wide ranges of biological
and pharmaceutical importance [32], in the present study,
we report the synthesis, spectroscopic and structural
characterization and the X-ray diffraction (XRD) study
of the title compound, too, as well as for the comparisons
of the geometrical features with related compounds in the
literature. The structure of the title compound confirms
the molecular formula based on microanalysis, IR, Uv-vis
and NMR spectra beside X-ray diffraction data.
2. Experimental
2.1. Synthesis of the Title Compound
The title compound was prepared by the reaction of 4-
benzoyl-1,5-diphenyl-1H-pyrazole-3-carboxylic acid am-
ide with DMF and SOCl2 (Figure 1). A cold solution of
the acid amide (0.37 g, 1.0 mmol) in a mixture of DMF
(0.7 mL) and SOCl2 (0.15 mL) was stirred at 0˚C - 5˚C
for 2 h similarly given in [5], and the solution was left
stirring overnight. Then the mixture was poured over
crushed ice and the precipitate formed was filtered off,
washed with water and recrystallized from methanol and
dried on P2O5 M.p. 167˚C, yield 70% (0.245 g). The au-
thenticity of the compound has been established by mi-
croanalyses, UV, IR, 1H and 13C NMR spectra.
2.2. Materials and Physical Measurements
The melting point was determined on an Electrother-
malModel 9200 apparatus and is uncorrected. The IR ab
*Corresponding author.
C
opyright © 2012 SciRes. CSTA

E. KORKUSUZ ET AL.
2
OO
Ph
Ph NN
OH
Ph
SOCl2
Ph
Ph NN
Cl
Ph
OO
NH3
Ph
Ph NN
NH2
Ph
OO
SOCl2+DMF
0-5 oC
Ph
Ph NN
CN
Ph
O
Ref. [Ref. [
28] 29]
Figure 1. Chemical structure and synthesis pathway of the title compound.
sorption spectrum (Figure 6) was obtained in the region
of 400 - 4000 cm–1 with a resolution of 4 cm–1 as KBr
pellet using a Jasco Plus Model 460 FT IR spectrometer.
Microanalysis was performed with a Carlo Erba Ele-
mental Analyzer, model 1108. UV-vis spectrum was re-
corded in the range of 200 nm to 1100 nm using a
Lambda 35 Perkin-Elmer spectrophotometer for the op-
tical transmission studies (Figure 5). The 1H and 13C
NMR (Figure 7) spectra were determined on a Bruker
Avance 400 model spectrometer at 400 MHz and 100
MHz, respectively. All materials were purchased from
commercial companies (Merck, Sigma, Aldrich and
Fluka) and used directly without further purification.
Solvents were dried by refluxing with the appropriate
drying agents and distilled before use.
2.3. X-Ray Crystallography
For the crystal structure determination, the single-crystal
of the compound C23 H15N3O was used for data collec-
tion on a four-circle Rigaku R-AXIS RAPID-S diffrac-
tometer (equipped with a two-dimensional area IP detec-
tor). The graphite-mon-chromatized Mo Kα radiation (λ =
0.71073 Å) and oscillation scans technique with Δω = 5˚
for one image were used for data collection. The lattice
parameters were determined by the least-squares meth-
ods on the basis of all reflections with F2 > 2σ(F2). Inte-
gration of the intensities, correction for Lorentz and po-
larization effects and cell refinement was performed us-
ing CrystalClear software [33]. The structures were solved
by direct methods using SHELXS-97 [34] and refined by
a full-matrix least-squares procedure using the program
SHELXL-97 [34]. H atoms were positioned geometri-
cally and refined using a riding model, fixing the aro-
matic C-H distances at 0.93 Å [Uiso(H) = 1.2Ueq(C)]. The
final difference Fourier maps showed no peaks of che-
mical significance. Molecular structure of the compound
showing the atomic numbering scheme is shown in Fig-
ure 2. The crystallography details for the structures de-
termination of the compound was presented in Table 1
Selected bond distances and bond angles are listed in
Table 2.
3. Results and Discussion
Title compound crystallizes in the monoclinic centro-
symmetric space group P 21/c (no: 14) with Z = 4. The
structure of the compound consists of cyano, benzoyl and
two phenyl fragments that connected to the pyrazole ring.
Due to the strong steric hindrance, phenyl moieties are
considerably twisted according to the pyrazole plane.
Dihedral angles between the phenyl planes 1-2, 1-3, 2-3
[C1/C6 (1), C7/C12 (2), C18/C23 (3)] are 39.18(8)˚,
59.57(7)˚, 88.98(7)˚, respectively. The N-C distances
1.330 and 1.362(3) Å deviate significantly from the mean
value of N-C distances in pyrazole rings 1.357(12) Å
[35-37]. It has been reported [38] that the N-N bond
length in the pyrazoline ring varies over a wide range,
from 1.234(8) to 1.385(4) Å, where the length depends
on the substituents bonded to the N atoms. Accordingly,
the length of the adjacent C=N bond ranges from 1.288(4)
to 1.461(8) Å. These differences are caused by a varying
degree of conjugation in the
 -electron portion of the
pyrazoline ring, which is sensitive to the nature of the
substituent(s) bonded to the atoms of the
 system. The
N2-N3 bond length of 1.358(3) Å found in the title
compound further extends this range, approximating the
length of a pure single bond 1.41 Å [39].
In the structure, benzoyl groups are joined by two C-
H···O [C(12)···O(1)a = 3.157(3) Å, C(12)-H···O(1)a =
119˚, symmetry code (a); 2 – x, –y, 1 – z] H bonds,
which lead to the formation of a centrosymmetric dimer
of the molecule in the crystal unit cell (Figure 3). The
title compound also contains intermolecular C-H…

interaction. Atom C(22) in the molecule at (x, y, z) acts
as hydrogen-bond donor to the C7/C12 phenyl ring in the
molecule at (–1 + x, y, –1 + z), so forming a chain run-
ning parallel to the [100] direction.
Figure 2. Molecular structure of the compound showing the
atomic numbering system. Displacement ellipsoids are drawn
at the 30% probability level.

E. KORKUSUZ ET AL. 3
Table 1. Crystallographic data and structure refinement parameters.
Empirical formula C23H15N3O
Formula weight 349.4 g/mol
Crystal colour colourless
Temperature 293(2) K
Wavelength 0.71073 Å
Crystal system Monoclinic
Space group P21/c
Unit cell dimensions a = 9.3167(2) Å, b = 20.6677(3) Å, c = 10.6143(3) Åβ = 112.665(3)°
Volume 1886.00(8) Å3
Z, Calculated density 4, 1.23 Mg m-3
Absorption coefficient 0.077 mm–1
F(000) 728
Crystal size 0.25 × 0.19 × 0.15 mm
Theta range for data collection 2.3 to 26.5 deg.
Limiting indices –11 ≤ h ≤ 11, –25 ≤ k ≤ 25, –13 ≤ l ≤ 12
Reflections collected/unique 39067/ 3862 [R(int) = 0.065]
Completeness to theta = 26.5 98.9 %
Max. and min. transmission 0.992 and 0.982
Refinement method Full-matrix least-squares on F2
Data/restraints/parameters 2819/0/244
Goodness-of-fit on F^2 1.066
Final R indices [I > 2 sigma (I)] R1 = 0.052, wR2 = 0.119
R indices (all data) R1 = 0.075, wR2 = 0.132
Largest diff. peak and hole 0.142 e Å–3and –0.200 e Å–3
Table 2. Selected bond lengths (Å) and angles (˚).
N(2)-N(3) 1.358(2) N(3)-N(2)-C(15) 103.6(2)
O(1)-C(13) 1.219(3) N(2)-N(3)-C(18) 118.3(2)
N(3)-C(18) 1.440(3) N(3)-C(17)-C(1) 123.2(2)
C(17)-C(14) 1.388(3) C(1)-C(17)-C(14) 130.4(2)
C(15)-C(14) 1.410(3) N(2)-C(15)-C(14) 113.0(2)
C(16)-N(1) 1.141(3) C(14)-C(15)-C(16) 128.0(2)
N(2)-C(15) 1.330(3) O(1)-C(13)-C(7) 120.4(2)
N(3)-C(17) 1.362(3) C(7)-C(13)-C(14) 121.1(2)
C(17)-C(1) 1.473(3) N(3)-C(18)-C(23) 119.5(2)
C(7)-C(13) 1.489(3)
C(15)-C(16) 1.438(3)
C(13)-C(14) 1.478(3)
Elemental analysis of compound for carbon, hydrogen,
and nitrogen are in good agreement with theoretical val-
ues. The theoretical and observed element percentages
respectively are: %C: 79.07 and 78.94, %H: 4.33 and
4.45, %N: 12.03 and 12.18.
Optical transmission spectrum of the compound is
shown in Figure 5. The range of optical transmittance
and the transparency cut-off are important parameters for
a single crystal used in optical applications. It has a wide
transmission window (300 to 1100 nm) with a transpar-
ency of nearly 100% and the UV cut-off wavelength oc-
curs at 242 nm. The wide transmission range in the entire
visible region is a useful property for opto-electronic
applications. Hence, the title compound has become a

E. KORKUSUZ ET AL.
4
Figure 3. Part of the crystal structure of the molecule, showing the formation of a centrosymmetric dimer. Atoms marked
with an (a) are at the symmetry position (2 – x, –y, 1 – z).
Figure 4. Packing diagram and H bonding geometry along the a-axis [symmetry code (a): 2 – x, –y, 1 – z].

E. KORKUSUZ ET AL. 5
good candidate for optoelectronic applications.
ompound The FT IR spectrum (Figure 6) of the title c
show sharp absorption bands occurred in the range
3095-3000 cm–1 due to the aromatic (C-H) stretching
vibrations. The sharp and middle-intensity IR absorption
band of the nitrile (-C=N) group founds at 2246 cm–1.
Weak combination or overtone bands appear in the
2000-1670 cm–1 region. The strong characteristic absorp-
tion band at 1652 cm–1 indicate the C=O (benzoyl) group
of the compound [40].
The sharp skeleton bands observed at 1614 (w), 1597
(m), 1578 (w), 1536 (w), 1498 (m), 1482 (s), 1461 (s)
cm–1 characterize the C…C and C…N vibrations of phenyl
and pyrazole rings. The additional absorption bands at
aromatic (C-H) in-plane bending vibrations. Moreover,
the strong absorption bands occurred at 765 (m), 742 (s),
696 (s), 665 (m) cm–1 belong to the …
980 (m), 937 (m), 913 (s), 850 (w) cm–1 are due to the
C-H bond out of
plane bending and C…C bond bending vibrations of the
substituted pyrazole and phenyl rings, respectively.
The structure of the title compound was further
characterized by NMR absorption. Important structural
information about can be obtained from its NMR spectra.
In the 13C-NMR spectrum (Figure 7) of the CDCl3 solu-
tion of the compound was observed = 188.24 (t, J = 4.5
Hz, Ph-C = O), 145.21 (s, C-3), and 138.26 ppm (t, J =
4.6 Hz, C-5). The peaks at 136.75, 133.48, 130.23,
129.78, 129.64, 129.23, 129.16, 128.92, 128.54, 128.32,
0.9
1.0
2004006008001000 12
0.5
0.6
0.7
0.8
Transmittance
Wavelenght ( nm)
Figure 5. Optical transmission spectrum of the title compound.
Figure 6. FT-IR spectrum for the title compound in KBr pellet.

E. KORKUSUZ ET AL.
6
Figure 7. A part of 13C-NMR spectrum of the title compound.
127.02, 126.79, 125.46, 124.77 ppm (s, C-4) are thought
cture of the
co
4. Conclusion
novel compound is a significant pre-
important from a medicinal point of view as well as their
y from the Research Center
Research Center of Atatürk
[1] A. M. Farghalhalil and O. A. El-
Sayed, Alexanaceutical Sciences,
ical Society, Vol. 68, 1991, p. 245.
-1
to represent the aromatic carbons and a singlet peak at
112.37 ppm represent the nitrile group [40].
Therefore, final confirmation of the stru
mpound was derived from its 1H-NMR spectrum:
=7.72 - 7.09 ppm a set of signals for aromatic protons.
Consequently, the
liminary compound due to the fact that original pyra-
zole-3-carboxylic acid derivative includes nitrile group in
its structure. It is air-stable in the solid state, crystallized
from methyl alcohol and insoluble in water. Additionally,
it has good solubility in common organic solvents, such
as CH2Cl2, THF, DMF, DMSO, CHCl3, acetone and
toluene. The authenticity of the compound has been es-
tablished by UV, IR, NMR, XRD and elemental analysis
techniques. The title compound characterized can be es-
sential in medicinal and biological applications. Some
pyrazole derivatives, as known, have been used to treat
some diseases [1-21,30-32]. The title structure may be
widespread biological significance. Further investigation
on the mechanism, potential activity and the optimal re-
action condition is currently in progress.
5. Acknowledgements
Financial support for this stud
of Erciyes University and the
University is gratefully acknowledged.
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