6
A. Derbel et al. / Journal of Molecular Structure 1079 (2015) 1–8
Table 4
Table 6
Distances and dihedral angles of the two compounds (I) and (II).
Hydrogen-bond geometry of the two compounds (I) and (II).
(C11N4H10)2ÁH2O
(C11N4H10)4ÁH2O
DAHÁ Á ÁA
d(DAH)
d(HÁ Á ÁA)
d(DÁ Á ÁA)
<DAHÁ Á ÁA
Distances (Å)
(C11N4H10)2ÁH2O
OW1AHW1ÁÁÁN2A
OW1AHW1ÁÁÁN2B
N3AAH3A1ÁÁÁN4Aa
N3AAH3A2ÁÁÁOW1b
C6AAH6AÁÁÁN3A
N3BAH3B1ÁÁÁN4Ba
C6BAH6BÁÁÁN3B
(C11N4H10)4ÁH2O
N7AH7AÁ Á ÁN8c
N7AH7BÁ Á ÁN2d
N3AH3AÁ Á ÁOW1
N3AH3BÁ Á ÁN4e
OW1AHWÁ Á ÁN6f
Ph1c–Pz2 = 3.777
Pz1c–Ph2 = 3.747
Pz2–Ph1 = 3.825
Ph2–Pz1 = 3.859
Ph1c–Ph2 = 6.078
Ph2–Ph1 = 4.947
Pz1c–Pz2 = 4.706
Pz2–Pz1 = 5.986
0.96
0.96
0.85
1.14
0.93
0.87
0.93
1.98
1.90
2.17
1.87
2.58
2.60
2.53
2.917
2.857
3.010
2.997
3.063
3.29
164.8
175.4
172
170
113
Ph1b–Pz1a = 3.654
Pz1b–Ph1a = 3.804
Ph1b–Ph1a = 5.181
Pz1b–Pz1a = 5.642
137
115
3.042
0.941
0.877
0.941
0.913
0.953
2.134
2.370
2.185
2.226
1.977
3.073
3.177
3.103
3.132
2.923
175.37
152.96
164.94
172.03
171.47
Angles (°)
Ph1b–Pz1a = 7.066
Pz1b–Ph1a = 7.066
Ph1c–Pz2 = 3.364
Pz1c–Ph2 = 5.151
Ph1c–Pz1c = 39.109
Pz2–Ph2 = 39.577
Ph1b–Pz1b = 34.847
Pz1a–Ph1a = 34.847
a
b
c
d
e
f
Àx + 3/2, Ày + 1/2, Àz.
x + 1/2, y + 1/2, z.
Àx + 1/2, Ày À 1/2, Àz.
x, y À 1, z.
Ph: Phenyl; Pz: Pyrazole.
a
3/2 À x, 1/2 + y, 1/2 À z.
b
x, 1 + y, z.
Àx, Ày + 1, Àz À 1.
Àx, y, Àz À 1/2.
c
x, y, 1 À z.
is 17.55 Å3 per water molecule. It corresponds well to the occupied
volume by this molecule in the crystal structures.
occupancy disorders in adjacent positions. These disorders have
been resolved and have refined the occupancy rates of partially dif-
ferent occupied sites by using the tools available in the SHELXL97
[29] software. For clarity of structure (I) we should represent a single
position. The crystal structure of the (C11N4H10)4ÁH2O compound is
determined from single-crystal X-ray diffraction data collected at
room temperature using an Enraf–Nonius CAD-4 diffractometer
Result and discussion
Infrared spectroscopy
The spectrum of the compound (I) and (II) shows bands at
3329 cmÀ1 assigned to an asymmetric NH2 stretching band. The
characteristic band at 3228 cmÀ1 is assigned to a symmetric NH2
stretching band [32–34]. The aromatic structure shows the pres-
ence of CAH stretching vibration in the characteristic region
with graphite-monochromated Mo K
a radiation [30]. The reflec-
tions were corrected for Lorentz and polarization effects; absorption
correction was obtained via a psi-scan [31] and secondary extinction
correction was applied too [26].
Experimental conditions used for the intensity data collection
and the refinement results are listed in Table 1. All atoms were
refined with anisotropic thermal parameters. The significant bond
lengths and angles are listed in Table 2. The atomic coordinates and
the displacement parameters are reported in Tables S1–S4 (Supple-
mentary materials).
The cell parameters of two compounds are almost similar.
Indeed, the two compounds crystallizes in the monoclinic system
with b angles fairly close and such as b and c parameters are prac-
tically the same, while the a parameter of the compound (II) is dou-
ble that of the compound (I). This is explained by the decline in
symmetry that accompanies the resulting vacancy of water mole-
cules in compound (II).
3100–3000 cmÀ1 [35]. The band arising from
m (C„N) was
observed at 2216 cmÀ1 [32,33]. The most characteristic bands are
those at 1653–1410 cmÀ1, attributable to the pyrazole C@C and
C@N groups [32–34]. The band in the 1080–1000 cmÀ1 region
has been assigned to the pyrazole NAN group [36]. For pyrazoles,
it must be indicating that a lone pair of nitrogen N in the NH2 group
is conjugated with the pyrazole ring. These justify the decrease of
the NAH vibration band (3329 cmÀ1, 3228 cmÀ1). Whereas, for pri-
mary amines NAH vibrates between 3400 cmÀ1 for symmetric
stretching and 3500 cmÀ1 for asymmetric stretching (Fig. 2, Table
3). The three spectra exhibit the same attributed band of each spec-
trum peak. While the IR spectra of the two compounds (I) and (II)
shows an enlargement of the band between 3300 and 2800 cmÀ1
due to the presence of water molecules and the overlap of vibra-
tion modes (OAH) and (CAH, NAH).
,
The comparison of volumes per formulary unit shows that the
compound (I) has a larger volume than in compound (I). This gap
m
m
Table 5
Distances and bond angles of the two compounds (I) and (II).
Compound (I)
Compound (II)
N3AbAOW1AN3A = 122.51°
N3AbAOW1AN2A = 100.64°
N3AOW1AN3a = 116.8°
N3AOW1AN6 = 98.8°
OW1AN2A = 2.917 Å
OW1AN2Ab = 2.917 Å
OW1AN3Ab = 2.997 Å
OW1AN3A = 2.997 Å
N3AbAOW1AN2Ab = 105.94°
N3AAOW1AN2Ab = 100.64°
N3AAOW1AN2A = 105.94°
N2AbAOW1AN2A = 122.95°
OW1AN6 = 2.923 Å
OW1AN6a = 2.923 Å
OW1AN3 = 3.104 Å
OW1AN3a = 3.104 Å
N3AOW1AN6a = 118.5°
N3aAOW1AN6a = 98.8°
N3aAOW1AN6 = 118.5°
N6aAOW1AN6 = 105.7°
a
Àx, y, Àz À 1/2.
1 À x, y, 1/2 À z.
b
Derbel, Amira
