Crystal structure, quantum mechanical investigation, IR and NMR
spectroscopy of two new organic salts: (C
8
H
12
NO)$[NO
3
] (I) and
(C
8
H
14
N
4
)$[ClO
4
]
2
(II)
I. Bayar
a
, L. Khedhiri
a
, S. Soudani
a
, F. Lefebvre
b
, P.S. Pereira da Silva
c
, C. Ben Nasr
a, *
a
Laboratoire de Chimie des Mat eriaux, Facult e des Sciences de Bizerte, 7021, Zarzouna, Universit e de Carthage, Tunisie
b
Laboratoire de Chimie Organom etallique de Surface (LCOMS), Ecole Sup erieure de Chimie Physique Electronique, 69626, Villeurbanne Cedex, France
c
CFisUC, Department of Physics, University of Coimbra, 3004e516, Coimbra, Portugal
article info
Article history:
Received 2 January 2018
Received in revised form
7 February 2018
Accepted 8 February 2018
Available online 9 February 2018
Keywords:
Single crystal X-ray diffraction analysis
Solid-state NMR
Hirshfeld surface
DFT calculations
abstract
Two new organic-inorganic hybrid materials, 4-methoxybenzylammonium nitrate, (C
8
H
12
NO)$[NO
3
] (I),
and 2-(1-piperazinyl)pyrimidinium bis(perchlorate), (C
8
H
14
N
4
)$[ClO
4
]
2
(II), have been synthesized by an
acid/base reaction at room temperature, their structures were determined by single crystal X-ray
diffraction. Compound (I) crystallizes in the orthorhombic system and Pnma space group with
a ¼ 15.7908 (7), b ¼ 6.8032 (3), c ¼ 8.7091 (4) Å, V ¼ 935.60 (7) Å
3
with Z ¼ 4. Full-matrix least-squares
refinement converged at R ¼ 0.038 and wR(F
2
) ¼ 0.115. Compound (II) belongs to the monoclinic system,
space group P2
1
/c with the following parameters: a ¼ 10.798(2), b ¼ 7.330(1), c ¼ 21.186(2) Å, b ¼ 120.641
(4)
, V ¼ 1442.7 (3) Å
3
and Z ¼ 4. The structure was refined to R ¼ 0.044, wR(F
2
) ¼ 0.132.
In the structures of (I) and (II), the anionic and cationic entities are interconnected by hydrogen
bonding contacts forming three-dimensional networks. Intermolecular interactions were investigated by
Hirshfeld surfaces and the contacts of the four different chloride atoms in (II) were compared. The
Molecular Electrostatic Potential (MEP) maps and the HOMO and LUMO energy gaps of both compounds
were computed. The vibrational absorption bands were identified by infrared spectroscopy. These
compounds were also investigated by solid-state
13
C,
35
Cl and
15
N NMR spectroscopy. DFT calculations
allowed the attribution of the IR and NMR bands.
© 2018 Elsevier B.V. All rights reserved.
1. Introduction
Hydrogen bonds of hybrid compounds are of great interest
because of their widespread biological occurrence [1 ,2]. The su-
pramolecular networks become especially interesting when the
cation and anion can participate in hydrogen-bonding. In recent
years, much attention has been devoted to the study of perchlorate
and nitrate salts containing organic cations owing to their inter-
esting properties such as ferroelectric and dielectric behaviors
[3e5].
Perchlorate and nitrate anions are Lewis bases used as ligands
for the elaboration of metal complexes having interesting appli-
cations in various fields: stabilization of PVC, protection of wood,
catalysis, pesticides, fungicides, pharmacology, etc. [6e10]. Several
organic cations (such as protonated amines) can be used for the
stabilization of these anions especially benzylammonium and
pyrimidinium derivatives [11 , 12].
Benzylamine and its derivatives have been widely studied as
precursors in organic synthesis. They are also used in the industrial
production of many pharmaceuticals including alniditan, lacosa-
mide, moxifloxacin, and nebivolol [13e17].
Pyrimidine and its derivatives are biologically important as they
occur in nature as components of nucleic acid. Some pyrimidine
derivatives are used as antifolate drugs [18].
In order to enhance the varieties of materials and to examine the
influence of hydrogen bonds on the chemical and structural fea-
tures, we report herein the chemical preparation and crystal
structure of two new organic salts, (C
8
H
12
NO)$[NO
3
] (I) and
(C
8
H
14
N
4
)$[ClO
4
]
2
(II).
* Corresponding author.
E-mail address: cherif_bennasr@yahoo.fr (C. Ben Nasr).
Contents lists available at ScienceDirect
Journal of Molecular Structure
journal homepage: http://www.elsevier.com/locate/molstruc
https://doi.org/10.1016/j.molstruc.2018.02.032
0022-2860/© 2018 Elsevier B.V. All rights reserved.
Journal of Molecular Structure 1161 (2018) 185e193