Three substituted (E)-3-aryl-2-(thienyl)-acrylonitriles: Isolated molecules, simple hydrogen-bonded chains and hydrogen-bonded sheets

Article abstract of DOI:10.1107/S0108270106026874

The structure of (E)-2-(2-thienyl)-3-(3,4,5-trimethoxyphenyl)- acrylonitrile, C₁₆H₁₅NO₃S, contains no direction-specific intermolecular interactions. The molecules of (E)-3-(4-bromophenyl)-2-(2-thienyl)acrylonitrile, C

Full text of DOI:10.1107/S0108270106026874

organic compounds
Acta Crystallographica Section C
Crystal Structure
Communications
Compound (II) is isomorphous and isostructural with
the chloro analogue, viz. (IV) (Cobo et al., 2005). In (II),
there is a signi®cant rotation of the aryl group around the
ISSN 0108-2701
Three substituted (E)-3-aryl-2-(thienyl)-
acrylonitriles: isolated molecules,
simple hydrogen-bonded chains and
hydrogen-bonded sheets
a
a
b
Â
Debora Cobo, Jairo Quiroga, Jose M. de la Torre, Justo
C11ÐC17 bond, so that this fragment is not coplanar with the
rest of the molecule (Table 2). There is no obvious reason for
this conformational difference between compounds (I) and
(II), as the aryl ring in (II) is not involved in any hydrogen
bonding. In the isostructural pair (II) and (IV), although not
in compound (I), the 2-thienyl group exhibits orientational
disorder over two sets of sites corresponding to a 180ꢀ rotation
about the C2ÐC27 bond. The populations of the major and
minor conformers in compounds (II) and (IV) are experi-
mentally indistinguishable: 0.798 (3) and 0.202 (3) in (II), and
0.802 (3) and 0.198 (3) in (IV).
Cobo,b John N. Lowc and Christopher Glidewelld*
a
Â
Â
Â
Grupo de Investigacion de Compuestos Heterocõclicos, Departamento de Quõmica,
b
Â
Universidad de Valle, AA 25360 Cali, Colombia, Departamento de Quõmica
Inorganica y Organica, Universidad de Jaen, 23071 Jaen, Spain, cDepartment of
Chemistry, University of Aberdeen, Meston Walk, Old Aberdeen AB24 3UE,
Scotland, and dSchool of Chemistry, University of St Andrews, Fife KY16 9ST,
Scotland
Â
Â
Â
Â
Correspondence e-mail: cg@st-andrews.ac.uk
Received 22 June 2006
Accepted 11 July 2006
Online 11 August 2006
The molecules of compound (III) are almost planar, as
shown by the key torsion angles (Table 4). In (I)±(III), the
nitrile components exhibit quite long CÐC bonds and very
short CÐN bonds. The remaining bond distances in (I)±(III)
show no unusual features.
There are no direction-speci®c intermolecular interactions
in the structure of compound (I). In particular, CÐHÁ Á ÁN, CÐ
HÁ Á ÁO and CÐHÁ Á Áꢀ(arene) hydrogen bonds and aromatic
ꢀ±ꢀ stacking interactions are all absent, so that the structure
consists of effectively isolated molecules.
The structure of (E)-2-(2-thienyl)-3-(3,4,5-trimethoxyphenyl)-
acrylonitrile, C16H15NO3S, contains no direction-speci®c inter-
molecular interactions. The molecules of (E)-3-(4-
bromophenyl)-2-(2-thienyl)acrylonitrile, C13H8BrNS, exhibit
orientational disorder of the thienyl fragment, and the
molecules are linked into simple C(5) chains by a single CÐ
HÁ Á ÁN hydrogen bond. In (E)-3-phenyl-2-(3-thienyl)acrylo-
nitrile, C13H9NS, the molecules are linked into sheets by a
combination of one CÐHÁ Á ÁN hydrogen bond and one CÐ
HÁ Á Áꢀ(arene) hydrogen bond.
By contrast, the molecules of compound (II) are linked by a
single CÐHÁ Á ÁN hydrogen bond (Table 3), exactly as in
compound (IV). Alkene atom C17 in the molecule at (x, y, z)
Comment
We report here the structures of three substituted (E)-3-aryl-
2-(thienyl)acrylonitriles, namely (E)-2-(2-thienyl)-3-(3,4,5-
trimethoxyphenyl)acrylonitrile, (I) (Fig. 1), (E)-3-(4-bromo-
phenyl)-2-(2-thienyl)acrylonitrile, (II) (Fig. 2), and (E)-3-
phenyl-2-(3-thienyl)acrylonitrile, (III) (Fig. 3), which have
been synthesized for use as potential intermediates in the
synthesis of new fused heterocyclic systems. The structure of
the analogous (E)-3-(4-chlorophenyl)-2-(2-thienyl)acrylo-
nitrile, (IV), was reported recently (Cobo et al., 2005).
For compound (I), the key torsion angles (Table 1) show
that the non-H atoms are very nearly coplanar, with the sole
exception of atom C141 of the 4-methoxy group. The exocyclic
angles at the methoxy substituents in (I) show the usual
patterns of behaviour, with markedly different CÐCÐO
angles for the 3- and 5-methoxy substituents, which are
effectively coplanar with the aryl ring, and rather similar
angles for the 4-methoxy substituent, where the methyl C
atom is displaced from the plane of the aryl ring by
Figure 1
The molecule of compound (I), showing the atom-labelling scheme.
Displacement ellipsoids are drawn at the 30% probability level and H
atoms are shown as small spheres of arbitrary radii.
Ê
1.261 (2) A.
o550 # 2006 International Union of Crystallography
DOI: 10.1107/S0108270106026874
Acta Cryst. (2006). C62, o550±o553

organic compounds
acts as hydrogen-bond donor to atom N27 in the molecule at
12 + x, 12 y, 12 + z), so forming a C(5) chain (Bernstein et al.,
1995) running parallel to the [101] direction and generated by
the n-glide plane at y = 14 (Fig. 4). Two chains of this type, which
are related to one another by inversion and hence are anti-
parallel, and generated by the n-glide planes at y = 14 and y = 43,
pass through each unit cell, but there are no direction-speci®c
interactions between adjacent chains.
(
In the structure of compound (III), the molecules are linked
into sheets by a combination of CÐHÁ Á ÁN and CÐ
HÁ Á Áꢀ(arene) hydrogen bonds (Table 5). Atom C2 in the
molecule at (x, y, z) acts as hydrogen-bond donor to atom N37
in the molecule at (1
x, y, 1
z), so generating by
inversion an R22(12) dimer centred at (21, 0, 12) (Fig. 5). In
addition, atoms C13 in the molecules at (x, y, z) and (1 x,
y, 1
z), which form a dimer centred at (12, 0, 21), act as
hydrogen-bond donors to the aryl rings of the molecules at
(2 x, 12 + y, 23 z) and ( 1 + x, 21 y, 12 + z), respectively,
which themselves are components of dimers centred at
(32, 12, 1) and ( 21, 12, 0), respectively. Similarly, the aryl rings at
(x, y, z) and (1 x, y, 1 z) accept hydrogen bonds from
atom C13 in the molecules at (2 x, 12 + y, 23 z) and ( 1 + x,
Figure 2
The molecule of compound (II), showing the atom-labelling scheme.
Displacement ellipsoids are drawn at the 30% probability level and H
atoms are shown as small spheres of arbitrary radii.
1
2
y, 12 + z), themselves parts of dimers centred at (23, 12, 1)
Figure 3
The molecule of compound (III), showing the atom-labelling scheme.
Displacement ellipsoids are drawn at the 30% probability level and H
atoms are shown as small spheres of arbitrary radii. For the sake of clarity,
only the major orientation of the disordered thienyl ring is shown.
Figure 5
Part of the crystal structure of compound (III), showing the formation of
an R22(12) dimer. For the sake of clarity, H atoms not involved in the motif
shown have been omitted. Atoms marked with an asterisk (*) are at the
symmetry position (1 x, y, 1 z).
Figure 4
Part of the crystal structure of compound (II), showing the formation of a
C(5) chain along [101]. For the sake of clarity, only the major orientation
of the disordered thienyl ring is shown, and H atoms not involved in the
motif shown have been omitted. Atoms marked with an asterisk (*) or a
Figure 6
A stereoview of part of the crystal structure of compound (III), showing
the formation of a hydrogen-bonded sheet parallel to (102). For the sake
of clarity, H atoms not involved in the motifs shown have been omitted.
hash symbol (#) are at the symmetry positions ( 12 + x, 21 y, 21 + z) and
(12 + x, 12 y,
+ z), respectively.
1
2
ꢁ
Acta Cryst. (2006). C62, o550±o553
Cobo et al.
C16H15NO3S, C13H8BrNS and C13H9NS o551

organic compounds
1
2
and (
,
12, 0), respectively. Propagation of this interaction
Compound (II)
then links the R22(12) dimers into a sheet parallel to (102)
(Fig. 6).
Crystal data
C13H8BrNS
Mr = 290.17
Monoclinic, P21=n
Ê
a = 3.8557 (2) A
b = 24.0484 (7) A
Ê
c = 12.5466 (4) A
ꢁ = 96.877 (2)ꢀ
V = 1154.99 (8) A
Z = 4
Dx = 1.669 Mg m
Mo Kꢂ radiation
ꢃ = 3.71 mm
T = 120 (2) K
Needle, colourless
0.38 Â 0.04 Â 0.03 mm
3
1
Experimental
Ê
Compounds (I)±(III) were prepared using procedures similar to that
employed for the synthesis of compound (IV) (Cobo et al., 2005). A
solution of 2-thiopheneacetonitrile [for (I) and (II)] or 3-thio-
pheneacetonitrile [for (III)] (1 mmol) and potassium tert-butoxide
(1 mmol) in anhydrous ethanol (3 ml) was stirred at room tempera-
ture for 15 min. A solution of the appropriate benzaldehyde
(1 mmol) in anhydrous ethanol (3 ml) was then added, and the
overall mixtures were then heated under re¯ux for 2±3 h. The
resulting solid products were collected by ®ltration, washed with
ethanol, dried, and ®nally crystallized from dimethylformamide to
give yellow crystals suitable for single-crystal X-ray diffraction.
Compound (I): m.p. 391±392 K, yield 70%; MS EI (30 eV) m/z (%):
302 (21), 301 (100, M+), 286 (39 M+ CH3), 226 (16). Compound (II):
m.p. 368±370 K, yield 68%; MS EI (30 eV) m/z (%): 292 (17), 291/289
(100/98, M+), 290 (22), 211 (16), 210 (81), 209 (89), 208 (91), 183 (16),
177 (35), 166 (19) 139 (16), 154 (17), 127 (10), 45 (14). Compound
(III): m.p. 348±349 K [literature m.p. 348 K (Stuart et al., 1986)], yield
60%.
3
Ê
Data collection
Bruker±Nonius KappaCCD area-
detector diffractometer
' and ! scans
Absorption correction: multi-scan
(SADABS; Sheldrick, 2003)
Tmin = 0.333, Tmax = 0.897
12766 measured re¯ections
2598 independent re¯ections
1983 re¯ections with I > 2ꢄ(I)
Rint = 0.059
ꢅmax = 27.5ꢀ
Re®nement
Re®nement on F2
R[F2 > 2ꢄ(F2)] = 0.040
wR(F2) = 0.081
S = 1.09
2598 re¯ections
w = 1/[ꢄ2(Fo2) + (0.032P)2
+ 0.6935P]
2
where P = (Fo + 2Fc2)/3
(Á/ꢄ)max = 0.001
3
Ê
Áꢆmax = 0.54 e A
3
Ê
0.76 e A
147 parameters
H-atom parameters constrained
Áꢆmin
=
Extinction correction: SHELXL97
(Sheldrick, 1997)
Extinction coef®cient: 0.0211 (12)
Compound (I)
Table 2
Selected geometric parameters (A, ) for (II).
ꢀ
Ê
Crystal data
C16H15NO3S
Mr = 301.36
Monoclinic, P21=c
Ê
a = 22.5423 (6) A
Z = 4
Dx = 1.413 Mg m
Mo Kꢂ radiation
ꢃ = 0.24 mm
T = 120 (2) K
Block, colourless
0.30 Â 0.20 Â 0.10 mm
C27ÐC271
1.446 (4)
C271ÐN27
1.143 (4)
38.7 (4)
3
1
S1ÐC2ÐC27ÐC17
C2ÐC27ÐC17ÐC11
5.2 (4)
178.1 (3)
C27ÐC17ÐC11ÐC12
Ê
b = 8.4647 (3) A
Ê
c = 7.4243 (2) A
ꢁ = 91.510 (2)ꢀ
V = 1416.17 (7) A
3
Ê
Table 3
Hydrogen-bond geometry (A, ) for (II).
Data collection
ꢀ
Ê
Bruker±Nonius KappaCCD area-
detector diffractometer
' and ! scans
Absorption correction: multi-scan
(SADABS; Sheldrick, 2003)
Tmin = 0.920, Tmax = 0.977
17457 measured re¯ections
3228 independent re¯ections
2538 re¯ections with I > 2ꢄ(I)
Rint = 0.041
DÐHÁ Á ÁA
C17ÐH17Á Á ÁN27i
Symmetry code: (i) x
DÐH
HÁ Á ÁA
DÁ Á ÁA
DÐHÁ Á ÁA
0.95
2.55
3.450 (4)
159
ꢅmax = 27.5ꢀ
1
2
;
y ‡ 12; z ‡ 12.
Re®nement
Re®nement on F2
R[F2 > 2ꢄ(F2)] = 0.038
wR(F2) = 0.113
S = 1.12
3228 re¯ections
w = 1/[ꢄ2(Fo2) + (0.0648P)2
+ 0.0444P]
Compound (III)
where P = (Fo2 + 2Fc2)/3
(Á/ꢄ)max = 0.001
Crystal data
3
Ê
C13H9NS
Mr = 211.27
Monoclinic, P21=c
Z = 4
Dx = 1.360 Mg m
Mo Kꢂ radiation
ꢃ = 0.27 mm
T = 120 (2) K
Áꢆmax = 0.40 e A
3
3
Ê
0.43 e A
193 parameters
H-atom parameters constrained
Áꢆmin
=
1
Ê
a = 9.6280 (11) A
Ê
b = 5.7190 (3) A
Table 1
Selected geometric parameters (A, ) for (I).
Ê
c = 19.247 (2) A
Block, yellow
0.49 Â 0.31 Â 0.20 mm
ꢀ
Ê
ꢁ = 103.129 (7)ꢀ
V = 1032.09 (17) A
3
Ê
C27ÐC271
1.443 (2)
C271ÐN27
1.145 (2)
Data collection
O13ÐC13ÐC12
O13ÐC13ÐC14
O14ÐC14ÐC13
124.05 (14)
115.33 (13)
120.47 (14)
O14ÐC14ÐC15
O15ÐC15ÐC14
O15ÐC15ÐC16
119.86 (13)
115.80 (12)
124.47 (14)
Bruker±Nonius KappaCCD area-
detector diffractometer
' and ! scans
Absorption correction: multi-scan
[SADABS (Sheldrick, 2003) and
EVALCCD (Duisenberg et al.,
2003)]
24963 measured re¯ections
2368 independent re¯ections
1788 re¯ections with I > 2ꢄ(I)
Rint = 0.036
ꢅmax = 27.5ꢀ
S1ÐC2ÐC27ÐC17
C2ÐC27ÐC17ÐC11
C27ÐC17ÐC11ÐC12
9.0 (2)
174.72 (15)
5.5 (3)
C12ÐC13ÐO13ÐC131
C13ÐC14ÐO14ÐC141
C16ÐC15ÐO15ÐC151
7.9 (2)
75.54 (17)
2.2 (2)
Tmin = 0.878, Tmax = 0.947
ꢁ
o552 Cobo et al. C16H15NO3S, C13H8BrNS and C13H9NS
Acta Cryst. (2006). C62, o550±o553

organic compounds
Re®nement
program(s) used to solve structure: SIR2004 (Burla et al., 2005);
program(s) used to re®ne structure: OSCAIL (McArdle, 2003) and
SHELXL97 (Sheldrick, 1997); molecular graphics: PLATON (Spek,
2003); software used to prepare material for publication: SHELXL97
and PRPKAPPA (Ferguson, 1999).
Re®nement on F2
R[F2 > 2ꢄ(F2)] = 0.067
wR(F2) = 0.206
S = 1.07
2368 re¯ections
w = 1/[ꢄ2(Fo2) + (0.1146P)2
+ 1.443P]
where P = (Fo2 + 2Fc2)/3
(Á/ꢄ)max < 0.001
3
Ê
Áꢆmax = 0.57 e A
3
Ê
0.67 e A
136 parameters
H-atom parameters constrained
Áꢆmin
=
X-ray data were collected at the EPSRC National X-ray
Crystallography Service, University of Southampton,
Table 4
Selected geometric parameters (A, ) for (III).
Â
Â
England. JC and JT thank the Consejerõa de Innovacion,
Ciencia y Empresa (Junta de Andalucõa, Spain), and the
ꢀ
Ê
Â
Â
Â
Universidad de Jaen for ®nancial support. JT also thanks the
C37ÐC371
1.444 (4)
C371ÐN37
1.146 (4)
1.7 (5)
Universidad de Jaen for a research scholarship supporting a
short stay at the EPSRC National X-ray Crystallography
Service. JQ and DC thank COLCIENCIAS and UNIVALLE
(Universidad del Valle, Colombia) for ®nancial support.
C2ÐC3ÐC37ÐC17
C3ÐC37ÐC17ÐC11
179.0 (3)
178.1 (2)
C37ÐC17ÐC11ÐC12
Table 5
Hydrogen-bond geometry (A, ) for (III).
Supplementary data for this paper are available from the IUCr electronic
archives (Reference: SK3037). Services for accessing these data are
described at the back of the journal.
ꢀ
Ê
Cg is the centroid of the C11±C16 ring.
DÐHÁ Á ÁA
DÐH
HÁ Á ÁA
DÁ Á ÁA
DÐHÁ Á ÁA
References
C2ÐH2Á Á ÁN37i
0.95
0.95
2.59
2.86
3.324 (5)
3.566 (4)
135
132
Bernstein, J., Davis, R. E., Shimoni, L. & Chang, N.-L. (1995). Angew. Chem.
Int. Ed. Engl. 34, 1555±1573.
Burla, M. C., Caliandro, R., Camalli, M., Carrozzini, B., Cascarano, G. L., De
Caro, L., Giacovazzo, C., Polidori, G. & Spagna, R. (2005). J. Appl. Cryst. 38,
381±388.
C13ÐH13Á Á ÁCgii
1
2
Symmetry codes: (i) x ‡ 1; y; z ‡ 1; (ii) x ‡ 2; y
;
z ‡ 32.
Cobo, D., Quiroga, J., Cobo, J., Low, J. N. & Glidewell, C. (2005). Acta Cryst.
E61, o3639±o3641.
Duisenberg, A. J. M., Hooft, R. W. W., Schreurs, A. M. M. & Kroon, J. (2000).
J. Appl. Cryst. 33, 893±898.
The space groups P21/c, P21/n and P21/c for compounds (I), (II)
and (III), respectively, were uniquely assigned from the systematic
absences. All H atoms were located in difference maps and then
Ê
treated as riding atoms, with CÐH distances of 0.95 A and with
Ê
Uiso(H) = 1.2Ueq(C), or CÐH = 0.98 A and Uiso(H) = 1.5Ueq(C) for
Duisenberg, A. J. M., Kroon-Batenburg, L. M. J. & Schreurs, A. M. M. (2003).
J. Appl. Cryst. 36, 220±229.
Ferguson, G. (1999). PRPKAPPA. University of Guelph, Canada.
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Macromolecular Crystallography, Part A, edited by C. W. Carter Jr & R. M.
Sweet, pp. 307±326. New York: Academic Press.
the methyl groups. In compound (II), the disorder of the thienyl
group was modelled using a common set of sites for atoms C2, C4 and
C5 in the two orientations and individual sites for the remaining
atoms of this unit, denoted S1 and C3 for the major orientation, and
S3 and C1 for the minor orientation. The re®ned site occupancies for
the two orientations were 0.798 (3) and 0.202 (3).
È
Sheldrick, G. M. (1997). SHELXL97. University of Gottingen, Germany.
Sheldrick, G. M. (2003). SADABS. Version 2.10. University of GoÈttingen,
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M. L., Castle, R. N., Dallas, J. L., John, B. K. & Johnson, L. F. (1986). J.
Heterocycl. Chem. 23, 1215±1234.
For all compounds, data collection: COLLECT (Nonius, 1999).
Cell re®nement: DENZO (Otwinowski
& Minor, 1997) and
COLLECT for (I) and (II); DIRAX/LSQ (Duisenberg et al., 2000)
for (III). Data reduction: DENZO and COLLECT for (I) and (II);
EVALCCD (Duisenberg et al., 2003) for (III). For all compounds,
ꢁ
Acta Cryst. (2006). C62, o550±o553
Cobo et al.
C16H15NO3S, C13H8BrNS and C13H9NS o553