Synthesis, Spectroscopic Characterization and X-ray Structure Analysis of 6-(2,5-Dichlorothiophen-3-yl)-2-methoxy-4-(4-methoxyphenyl)pyridine-3-carbonitrile

Article abstract of DOI:10.1007/s10870-016-0661-z

Abstract: The title compound was prepared by the condensation of an equimolar mixture of 1-(2,5-dichlorothiophen-3-yl)-3-(4-methoxyphenyl)prop-2-en-1-one, malononitrile and sodium hydroxide. The molecular structure was fully characterized using different spectroscopic methods. Mass ESI–HRMS measurements were performed. The HRESIMS analysis revealed the molecular formula, C₁₈H₁₂Cl₂N₂O₂SNa, with [M?+?Na]⁺ and [M?+?Na?+?2]⁺ and [M?+?Na?+?4]⁺ isotopic clusters characteristic for a dichlorinated compound. The compound was also thoroughly characterized by ¹H, ¹³C, NMR spectra and 2D NMR spectra (COSY, HSQC and HMBC). The molecular structure was confirmed by X-ray single crystal analysis. The new compound crystallizes in the orthorhombic, Pbcn space group with unit cell dimensions: a?=?31.901(7) ?, b?=?15.412(4) ?, c?=?7.3655(14) ?, V?=?3621.3(13) ?³ and Z?=?8. In the title compound, the central pyridine ring carries four substituents, a thiophene ring, a methoxyphenyl ring, a carbonitrile group and a methoxy group. The dihedral angles between the planes of the pyridine ring, the thiophene ring and the methoxyphenyl ring are 36.66 and 40.18°, respectively. Intermolecular C–H···O/N, π···π and anion···π [Cl···π] interactions are found in the crystal structure. All interactions consolidate a three dimensional network. Graphical Abstract: Synthesis, characterization, crystal, molecular structure, and crystal supramolecularity of 6-(2,5-dichlorothiophen-3-yl)-2-methoxy-4-(4-methoxyphenyl)pyridine-3-carbonitrile are reported. [Figure not available: see fulltext.]

Full text of DOI:10.1007/s10870-016-0661-z

J Chem Crystallogr
DOI 10.1007/s10870-016-0661-z
ORIGINAL PAPER
Synthesis, Spectroscopic Characterization and X-ray Structure
Analysis of 6-(2,5-Dichlorothiophen-3-yl)-2-methoxy-4-(4-
methoxyphenyl)pyridine-3-carbonitrile
Mahmoud Al-Refai1 Mohammad M. Ibrahim1 Armin Geyer2 Michael Marsch2
Basem F. Ali1,3
•
•
•
•
Received: 18 March 2016 / Accepted: 8 July 2016
Ó Springer Science+Business Media New York 2016
Abstract The title compound was prepared by the con-
densation of an equimolar mixture of 1-(2,5-dichlorothio-
phen-3-yl)-3-(4-methoxyphenyl)prop-2-en-1-one, malonon-
itrile and sodium hydroxide. The molecular structure was
fully characterized using different spectroscopic methods.
Mass ESI–HRMS measurements were performed. The
HRESIMS analysis revealed the molecular formula, C18H12
Cl2N2O2SNa, with [M ? Na]? and [M ? Na ? 2]? and
[M ? Na ? 4]? isotopic clusters characteristic for a
dichlorinated compound. The compound was also thor-
The dihedral angles between the planes of the pyridine
ring, the thiophene ring and the methoxyphenyl ring are
36.66 and 40.18°, respectively. Intermolecular C–HÁÁÁO/N,
pÁÁÁp and anionÁÁÁp [ClÁÁÁp] interactions are found in the
crystal structure. All interactions consolidate a three
dimensional network.
Graphical Abstract Synthesis, characterization, crystal,
molecular structure, and crystal supramolecularity of 6-
(2,5-dichlorothiophen-3-yl)-2-methoxy-4-(4-methoxyphenyl)
pyridine-3-carbonitrile are reported.
1
oughly characterized by H, 13C, NMR spectra and 2D
NMR spectra (COSY, HSQC and HMBC). The molecular
structure was confirmed by X-ray single crystal analysis.
The new compound crystallizes in the orthorhombic, Pbcn
˚
space group with unit cell dimensions: a = 31.901(7) A,
3
˚
˚
˚
b = 15.412(4) A, c = 7.3655(14) A, V = 3621.3(13) A
and Z = 8. In the title compound, the central pyridine ring
carries four substituents, a thiophene ring, a methox-
yphenyl ring, a carbonitrile group and a methoxy group.
& Basem F. Ali
bfali@kfu.edu.sa; bfali@aabu.edu.jo
O
1
Department of Chemistry, Al al-Bayt University,
Mafraq 25113, Jordan
2
CN
¨
Department of Chemistry, Philipps-Universitat Marburg,
Cl
Fachbereich Chemie, Hans Meerwein Strasse,
35032 Marburg, Germany
N
O
S
3
Present Address: Department of Chemistry, King Faisal
University, Al-Hasa, Saudi Arabia
Cl
123

J Chem Crystallogr
literature [9]. A solution of 2,5-dichlorothiophene, 1,
(15.2 g, 100 mmol) in dry carbon disulfide (25 ml) was
added dropwise, during 1 h, to a stirred mixture of anhy-
drous AlCl3 (15.0 g, 110 mmol) and acetyl chloride (7.9 g,
100 mmol) in dry CS2 (80 ml). The reaction mixture was
stirred at RT for 24 h. Cold water (50 ml) was then added
dropwise to the reaction with continuous stirring for 30 min
the organic layer was separated, washed with water
(4 9 30 ml), dried over anhydrous CaCl2 and the solvent
was evaporated to produce a solid product. Yield: 80 % [9].
Synthesis of 1-(2,5-dichlorothiophen-3-yl)-3-(4-meth-
oxyphenyl)prop-2-en-1-one, 4. An equimolar mixture of
the 4-methoxybenzaldehyde, KOH were dissolved in
MeOH (50 ml). To this solution 3-acetyl-2,5-dichloro-
thiophene, 2, in MeOH (10 ml) was added dropwise. After
the addition was completed, the reaction mixture was
stirred at RT for 10 h. The precipitate formed was filtered
off, washed with MeOH and dried without any further
purification.
Keywords Cyanopyridine Á Chalcone Á Spectroscopic
characterization Á Crystal supramolecularity Á C–HÁÁÁN/O Á
SÁÁÁS interactions Á ClÁÁÁp interactions Á pÁÁÁp interactions
Introduction
Pyridine is an integral part of B6-vitamins pyridoxine,
pyridoxal, pyridoxamine, and decarboxylase. Pyridine
derivatives, either natural or synthetic, possess interesting
pharmacological properties [1]. Pyridine heterocyclic
compounds have attracted an extensive attention due to their
possible pharmacological activities, such as antimicrobial,
antitumor and anti-inflammatory properties [2–6]. One class
of these heterocyclic compounds, cyanopyridines, which
have been used as precursor for the preparation of different
types of compounds such as nicotinamide, nicotinic acid and
isonicotinic acid [7, 8]. In continuation to our research in the
synthesis and structural characterization of a series of
compounds containing cyanopyridine derivatives, we herein
report the synthesis, spectroscopic characterization,
molecular and crystal structure analysis of the title com-
pound as one compound of a series that will be published
soon with biological activities.
Synthesis of 6-(2,5-Dichlorothiophen-3-yl)-2-Methoxy-4-
(4-Methoxyphenyl)Pyridine-3-Carbonitrile, 5
The synthesis was done according to literature method
[10]. A mixture of 1-(2,5-dichlorothiophen-3-yl)-3-(4-
methoxyphenyl)prop-2-en-1-one, 4, (0.01 mol), malononi-
trile (0.01 mol) and NaOH (0.01 mol) in 50 ml of MeOH
was refluxed for about 2 h. The reaction mixture was
cooled and then a pale yellow solid was obtained, filtered
off, air-dried, and purified using PTLC (20 9 20 cm) using
CH2Cl2: pentane (70:30 %) as a mobile phase to give the
Experimental
General Information
All reagents were purchased from Fluka and used as pur-
chased. Solvents were dried and distilled according to
standard protocols. 1H (500 MHz) and 13C (125 MHz)
NMR spectra were recorded in CDCl3 (used as an internal
standard) at 300 K on Bruker spectrometers. Chemical
shifts d are given in parts per million (ppm) and were
determined from the center of the respective coupling
pattern (s: singlet, d: doublet, dd: doublet of doublet, t:
triplet). ESI–HRMS measurements were performed on a
LTQ-FT mass spectrometer (Thermo Fisher Scientific).
Thin layer chromatography (TLC) monitoring of the reac-
tion was carried out using analytical TLC plates coated with
silica gel (60 F254, Merck). Preparative thin layer chro-
matography (PTLC) was carried out at room temperature (RT)
with the mobile phase being CHCl3/pentane (30:70) mixture.
1
title compound, Scheme 1. H NMR (CDCl3, 500 MHz):
d = 7.66 (d, J = 8.70 Hz, 2H, H-200,600), 7.63 (s,1H, H-5),
7.42 (s, 1H, H-40), 7.08 (d, J = 8.70 Hz, 2H, H-300, 500),
3.91 (s, 3H, OCH3-400), 4.16 (s, 3H, OCH3-2); 13C NMR
(CDCl3, 125 MHz) d = 164.91 (C-2), 161.26 (C-400),
156.19 (C-4), 151.46 (C-6), 135.69 (C-30), 130.00 (C-
200,600), 128.12 (C-100), 127.48 (C-40), 126.76 (C-50), 126.15
(C-20), 115.72 (CN), 115.65 (C-5), 114.53 (C-300,500), 93.07
(C-3), 55.51 (OCH3-400), 54.88 (OCH3-2); (?)-ESIMS m/z
391([M ? H]?, 48), 393 ([M ? H?2]?, 17), 413 ([M ? Na]?,
100), 415 ([M ? Na ? 2]?, 58), 417 ([M ? Na ? 4]?,
13); (1)-HRESIMS m/z 412.9896 [M ? Na]?, 414.9867
[M ? Na ? 2]?, 416.9837 [M ? Na ? 4]? (calcd for
C18H12Cl2N2O2SNa, 412.9889).
Synthesis
Structure Determination and Refinement
Synthesis of Starting Materials
A Bruker D8 Quest area detector was used for X-ray
crystal structure determinations. A total of 1814 frames
were collected. The total exposure time was 9.58 h.
The frames were integrated with the Bruker SAINT
software package [11] using a narrow-frame algorithm.
Scheme 1 outlines the synthesis of all starting materials
and the title compound. The synthesis of 3-acetyl-2,5-
dichloro-thiophene, 2, was accomplished as described in
123

J Chem Crystallogr
Cl
Cl
O
O
AlCl3
S
S
+
Cl
CS2, rt, 24hr
Cl
Cl
2
1
O
KOH, MeOH
rt, 10hr
H
O
3
O
Cl
O
O
S
CN
O
CH3OH
Cl
CN
NC
+
Cl
NaOH
reflux, 2hr
N
S
Cl
4
5
Scheme 1 Reaction scheme for the synthesis of the title compound, 5
Table 1 Crystal data and
Empirical formula; formula weight
structure refinement for 5
Temperature (K)
C18.5 H13 Cl3 N2 O2 S; 433.72
100 (2)
˚
k (A)
0.71073
Crystal system, space group
Unit cell dimensions
Orthorhombic, Pbcn
˚
a = 31.901 (7) A
˚
b = 15.412 (4) A
˚
c = 7.3655 (14) A
a = b = c = 90°
3621.4 (13)
3
˚
V (A )
Z
8
Dcalc. (Mg/m3)
1.591
Absorption coefficient (mm-1
F (000)
)
0.639
1768
Crystal size (mm3)
0.412 9 0.048 9 0.045
Theta range for data collection
Limiting indices
2.327–25.274°
-38 B h B 34, -18 B k B 18, -7 B l B 8
Reflections collected
17,368
Completeness to theta = 25.125°
Independent reflections
Observed reflections
99.8 %
3291 [R (int) = 0.0564]
2675 [II [ 2 (I)]
3291
Reflections used for refinement
Refinement method
Full-matrix least-squares on F2
Data/restraints/parameters
Goodness-of-fit on F2
3291/0/229
1.146
R index (all data)
wR2 = 0.1414
R1 = 0.0614
0.0007 (2)
R index conventional [I [ 2sigma (I)]
Extinction coefficient
-3
˚
0.712 and -0.507 e A
Largest diff. peak and hole
123

J Chem Crystallogr
Fig. 1 a ESIMS analysis for 5; b 1H NMR spectrum (CDCl3, 500 MHz) of 5. The signal at 5.32 due to the presence of traces of CH2Cl2; c 13
NMR spectrum (CDCl3, 125 MHz) for 5; d the HSQC spectrum for 5 with selected H,H COSY (—) and HMBC (?) correlations
C
˚ ˚
cell dimensions of a = 31.901 (7) A, b = 15.412 (4) A,
The integration of the data using an orthorhombic unit
cell yielded a total of 17,383 reflections to a maximum
3
˚
˚
c = 7.3655 (14) A, volume = 3621.3 (13) A , are based
upon the refinement of the XYZ-centroids of 93 reflections
above 20 r(I) with 6.909° \ 2h \ 40.64°. The systematic
absence conditions leads to the space group Pbcn. Data
were corrected for absorption effects using the multi-scan
˚
h angle of 25.27° (0.83 A resolution), of which
3293 were independent (average redundancy 5.279,
completeness = 99.8 %, Rint = 5.64 %, Rsig = 4.43 %)
and 2677 (81.29 %) were greater than 2r (F2). The final
123

J Chem Crystallogr
Fig. 1 continued
123

J Chem Crystallogr
˚
Table 2 Selected bond distances and angles (A, °) in 5
Bond distances
Cl1–C11
Cl2–C12
S1–C12
S1–C11
O1–C2
1.718 (5)
1.719 (5)
1.723 (5)
1.725 (5)
1.375 (5)
1.432 (6)
1.356 (5)
1.437 (5)
1.318 (6)
N1–C8
1.356 (6)
1.141 (6)
1.380 (7)
1.391 (7)
1.478 (6)
1.395 (6)
1.406 (6)
1.453 (7)
1.388 (8)
N2–C18
C2–C16
C2–C3
C5–C6
O1–C1
C6–C15
C6–C7
O2–C13
O2–C14
N1–C13
C15–C18
C16–C17
Bond angles
C12–S1–C11
C2–O1–C1
C13–N1–C8
O1–C2–C16
O1–C2–C3
O1–C2–C16
C17–C5–C4
C17–C5–C6
N1–C8–C7
89.7 (2)
N1–C8–C9
113.9 (4)
122.7 (4)
126.2 (4)
113.7 (4)
120.1 (3)
118.0 (3)
119.7 (4)
124.3 (4)
116.0 (4)
117.3 (4)
116.6 (4)
124.9 (4)
115.3 (4)
124.8 (4)
118.9 (4)
121.8 (4)
123.5 (4)
C7–C8–C9
C10–C11–Cl1
C10–C11–S1
Cl1–C11–S1
Cl2–C12–S1
N1–C13–O2
N1–C13–C15
O2–C13–C15
Torsion angles
C1–O1–C2–C16
C1–O1–C2–C3
C17–C5–C6–C15
C4–C5–C6–C15
C17–C5–C6–C7
C4–C5–C6–C7
6.6 (7)
N1–C8–C9–C12
N1–C8–C9–C10
C7–C8–C9–C10
C14–O2–C13–N1
C14–O2–C13–C15
C5–C6–C15–C18
141.9 (5)
-33.9 (6)
146.6 (5)
-2.5 (6)
177.0 (4)
7.4 (7)
-173.9 (4)
41.4 (7)
-140.5 (5)
-138.4 (5)
39.7 (6)
the electron density of the disordered solvent (CH2Cl2). All
H atoms were placed in their calculated positions and
included in the refinement using the riding model. Crystal
and experimental data for 4 are listed in Table 1.
Fig. 2 Molecular structure of the title compound, with the atomic-
labeling scheme. Displacement ellipsoids are drawn at the 50 %
probability level
method (SADABS) [11]. The ratio of minimum to maxi-
mum apparent transmission was 0.849. The calculated
minimum and maximum transmission coefficients (based
on crystal size) are 0.7790 and 0.9720. The final aniso-
tropic full-matrix least-squares refinement [12] on F2 with
229 variables converged at R1 = 0.0615, for the observed
data and wR2 = 0.1414 for all data. The goodness-of-fit
was 1.146. The largest peak in the final difference electron
Results and Discussion
Synthesis and Spectroscopic Characterization
The synthesis of 3-acetyl-2,5-dichloro-thiophene, 2, was
accomplished as described in literature [9] by Friedel–Crafts
acylation using 2,5-dichlorthiophene, 1, acetyl chloride,
anhydrous AlCl3 as a Lewis acid mediator and CS2 as the
solvent. The chalcone, 1-(2,5-dichlorothiophen-3-yl)-3-(4-
methoxyphenyl)prop-2-en-1-one, 4, was prepared by the
Claisen–Schmidt condensation of 3-acetyl-2,5-dichloro-
thiophene, 2, and 4-methoxybenzaldehyde, 3, in the pres-
ence of KOH as indicated in Scheme 1. The reaction of
1-(2,5-dichlorothiophen-3-yl)-3-(4-methoxyphenyl)prop-2-
-
3
˚
density synthesis was 0.706 e /A and the largest hole was
-
3
-
3
˚
˚
-1.341 e /A with an RMS deviation of 0.136 e /A . On
the basis of the final model, the calculated density was
1.591 g/cm3 and F (000), 1768 e-. The refinement of half
CH2Cl2 (inversion symmetry) was not successful, therefor
the PLATON/SQUEEZE routine [13] was used to remove
123

J Chem Crystallogr
Fig. 3 Shows: a pÁÁÁp stacking and centroid–centroid distances
between two molecules; b C–HÁÁÁO/N intermolecular interactions.
pÁÁÁp interactions shown as green–gray multi-band cylinders.
Hydrogen bonds are shown by dashed lines (C–HÁÁÁN in blue, C–
HÁÁÁO in red). Hydrogen atoms not involved in hydrogen bonding
omitted for clarity
en-1-one, 4, with malononitrile in the presence of methanol
as solvent and sodium hydroxide as a base, yielded the title
compound 6-(2,5-dichlorothiophen-3-yl)-2-methoxy-4-(4-
methoxyphenyl)pyridine-3-carbonitrile, 5, Scheme 1. The
structure of 5 was established using many spectroscopic
techniques and further confirmed by its single crystal
structure.
[M ? Na ? 4]? which confirmed the presence of two
chlorine atoms. The molecular formula was determined to
be C18H12Cl2N2O2S from the positive ion HRESIMS at m/z
412.9896 [M ? Na]?, (calcd for C18H12Cl2N2O2SNa,
412.9889), Fig. 1.
1H- and 13C-NMR Spectroscopy
Mass Spectroscopy
The 1H NMR spectrum of 5, Fig. 1, show the characteristic
pattern of a 1,4-disubstituted benzene ring at d = 7.66 (d,
J = 8.70 Hz, 2H, H-200,600), and 7.08 (d, J = 8.70 Hz, 2H,
The ESIMS spectra of 5 exhibited a pseudomolecular ion
peak at m/z 413 [M ? Na]?, 415 [M ? Na ? 2]?, 417
123

J Chem Crystallogr
˚
while C-6 showed correlations with the protons at 7.63 (H-
5) and 7.42 (H-40). Finally all the other carbons were
assigned unambiguously based on the complete analysis of
the 2D spectra (Fig. 1).
Table 3 Hydrogen bond parameters (A, °) in 5
D–HÁÁÁA
HÁÁÁA
D–H
D…A
D–HÁÁÁA
C–HÁÁÁO interactions
(p)C3–H11ÁÁÁO2a
H2C14–H3ÁÁÁO1b
C–HÁÁÁN interactions
(p)C4–H12ÁÁÁN2a
2.451
2.681
0.95
0.98
3.388
3.533
169
145
X-ray Structure Analysis
Molecular Structure
2.632
0.95
3.482
149
Symmetry codes: a(1/2 - x, 1/2 ? y,z); b(1/2 - x, 1.5 - y, -1/
2 ? z)
The crystallographic asymmetric unit contains one inde-
pendent molecule of the title compound (Fig. 2). Selected
geometrical parameters for the title compound are given
Table 2, fall in normal ranges [14–16]. In the title com-
pound, the central pyridine ring carries four substituents, a
thiophene ring, a methoxyphenyl ring, a carbonitrile group
and a methoxy group. The dichlorothiophene and the
methoxyphenyl rings are twisted compared to the pyridine
ring with dihedral angles of 36.66 and 40.18°, respectively.
The two aromatic rings of the biaryl group are rotated 39.7°
against each other while the thienyl group adopts a tor-
sional angle of -33.8°. In the methoxyphenyl ring, the O1–
H-300, 500), two singlets at d = 7.63 (s,1H), 7.42 (s, 1H)
attributed to H-5, H-40, respectively and two methoxy
group at d = 3.91 (s, 3H, OCH3-400), 4.16 (s, 3H, OCH3-2).
A detailed analysis of the 13C NMR spectrum, Fig. 1,
with the aid of HSQC data showed the presence of nine sp2
quaternary carbons at d 164.91 (C-2), 161.26 (C-400),
156.19 (C-4), 151.46 (C-6), 135.69 (C-30), 128.12 (C-100),
126.76 (C-50), 126.15 (C-20), 93.07 (C-3), four sp2 methine
carbons at 130.00 (C-200,600), 127.48 (C-40), 114.53 (C-
300,500), 115.65 (C-5) and the signal at 115.72 was attributed
to nitrile carbon. In addition the two methoxy groups were
appeared at 55.51 (OCH3-400), 54.88 (OCH3-2). The signal
at d 161.26 was assigned to C-400 on the basis of its cor-
relations observed in a HMBC experiment with the 1H
NMR signals at d 7.66 (H-200,600), 7.08 (2H, H-300, 500) and
3.91 (OCH3-400), and the C-4 signal at 156.19 showed a
correlation with the proton at 7.66 (H-200,600). In the HMPC
spectrum the carbon at d 164.91 (C-2) showed three bond
correlation with the methoxy group at d 4.16 (OCH3-2),
˚
C1 bond length [1.432 (6) A] is significantly shorter than
˚
O1–C2 [1.375 (5) A], indicating conjugation between
oxygen and the ring (C2–C17). On the other hand, the bond
angle [C16–C2–O1 = 124.9 (4)°] is larger than the bond
angle [C3–C2–O1 = 115.3 (4)°], which correlates will
with previously reported similar structures (see for exam-
ple [14–16]), might be attributed to the steric repulsion
between the aromatic rings and the methyl group.
Fig. 4 Intermolecular SÁÁÁS interactions (red–yellow rendered multi-band cylinders) between molecules. S atoms appear as spheres. Hydrogen
atoms omitted for clarity
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J Chem Crystallogr
Fig. 5 Partial crystal packing of the title compound: a viewed down
the b axis, showing the layers of molecules in the bc plane; b another
view (a is horizontal and b is vertical) of the partial packing; c Sphere
presentation of the packing showing the cavity. Hydrogen bonds are
shown by dashed lines (C–HÁÁÁN in blue, C–HÁÁÁO in red); pÁÁÁp
interactions shown as green–gray multi-band cylinders, while SÁÁÁS
and ClÁÁÁp interactions shown as rendered multi-band cylinders (black
and white, and red–white, respectively). Hydrogen atoms not involved
in hydrogen bonding omitted for clarity
123

J Chem Crystallogr
Crystal Supramolecularity
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The molecules are interacting extensively via pÁÁÁp inter-
actions leading to chains parallel to c-axis. These interac-
tions result between both the phenylÁÁÁpyridine rings where
each two molecules interact by two interactions of this type
with the centroidÁÁÁcentroid separation distances being
˚
3.589 and 3.906 A, Fig. 3. The electron rich phenyl ring
(by OCH3 group) and the electron deficient pyridine ring
(the presence of N atom) allowing the electron-rich and
electron-deficient aromatics to interact in the favored face
stacking motif in this case [17]. The resulting chains are
also involved in other interactions of the type C–HÁÁÁO and
C–HÁÁÁN interactions leading to layers in the bc plane as
depicted in Fig. 3. Detailed geometrical parameters for
these interactions are listed in Table 3. Moreover, within
these layers, SÁÁÁS interactions add extra supramolecularity
where the molecules are connected in a zigzag assembly
through thiopheneÁÁÁthiophene SÁÁÁS [Fig. 4; SÁÁÁS (x,
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¨
sitat Gottingen, Gottingen
13. Spek AL (2009) Acta Cryst D 65:148
˚
2 - y, -1/2 ? z) distance of 3.775 A] interactions. These
layers in bc plane interact with next layers parallel to a-axis
through what is called anionÁÁÁp interactions [18–20],
Fig. 5, manipulating the (thiophene)C–ClÁÁÁthiophene
14. Vishnupriya R, Suresh J, Bharkavi S, Perumal S, Lakshman PLN
(2014) Acta Cryst E 70:o968
15. Nagalakshmi RA, Suresh J, Maharani S, Kumar RR, Lakshman
PLN (2014) Acta Cryst E 70:525
16. Fun H-K, Chantrapromma S, Kobkeatthawin T, Padaki M, Isloor
AM (2010) Acta Cryst E 66:o1811
17. Martinez CR, Iverson BL (2012) Chem Sci 3:2191
18. Estarellas C, Bauza A, Frontera A, Quinonero D, Deya PM
(2011) Phys Chem Chem Phys 13:5696
(1 - x, y, ‘ - z) interactions,
C
aryl–ClÁÁÁp, [Caryl
–
˚
ClÁÁÁ(Cg)p distance of 3.949 A and D–ClÁÁÁCg(p) angle of
116°]. All these intermolecular interactions result in a three
dimensional network structure, Fig. 5, with a large cavity
which is filled with disordered CH2Cl2 molecules (not
shown).
19. Gamez P (2014) Inorg Chem Front 1:35
20. Bauza A, Mooibroek TJ, Frontera A (2016) CrystEngComm
18:10
Acknowledgments Financial support by the Deutsche Forschungs-
gemeinschaft (DFG) and Al al-Bayt University is gratefully
acknowledged.
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