(E)-1-(2,5-Dichloro-3-thien­yl)-3-(3,4-dimeth­oxy­phen­yl)prop-2-en-1-one

William T A Harrison; C S Chidan Kumar; H S Yathirajan; A N Mayekar; B Narayana

doi:10.1107/S1600536810035142

. 2010 Sep 4;66(Pt 10):o2479. doi: 10.1107/S1600536810035142

(E)-1-(2,5-Dichloro-3-thienyl)-3-(3,4-dimethoxyphenyl)prop-2-en-1-one

William T A Harrison ^a,^*, C S Chidan Kumar ^b, H S Yathirajan ^b, A N Mayekar ^b,^c, B Narayana ^d

PMCID: PMC2983303 PMID: 21587480

Abstract

In the title compound, C₁₅H₁₂Cl₂O₃S, the prop-2-en-1-one (enone) fragment is almost planar [C—C—C—O = 2.2 (4)°] and it subtends dihedral angles of 11.9 (2) and 11.0 (2)° with the thiophene and benzene rings, respectively. The dihedral angle between the aromatic rings is 3.47 (16)°. In the crystal, weak C—H⋯O and C—H⋯Cl interactions link the molecules, leading to R ₂ ²(14), R ₂ ²(24) and C(11) supramolecular motifs occurring within the three-dimensional network. Weak aromatic π–π stacking [centroid–centroid separations = 3.6823 (15) and 3.8722 (15) Å] may also help to consolidate the packing.

Related literature

For a related structure and background references, see: Jasinski et al. (2010 ▶). For reference structural data, see: Allen et al. (1987 ▶).

Experimental

Crystal data

C₁₅H₁₂Cl₂O₃S
M _r = 343.21
Monoclinic,
a = 8.9331 (2) Å
b = 8.9997 (2) Å
c = 18.8210 (5) Å
β = 100.181 (1)°
V = 1489.29 (6) Å³
Z = 4
Mo Kα radiation
μ = 0.58 mm⁻¹
T = 120 K
0.24 × 0.12 × 0.10 mm

Data collection

Nonius KappaCCD diffractometer
Absorption correction: multi-scan [SADABS (Bruker, 2003 ▶) and Blessing (1995 ▶)] T _min = 0.873, T _max = 0.944
22032 measured reflections
3424 independent reflections
2834 reflections with I > 2σ(I)
R _int = 0.056

Refinement

R[F ² > 2σ(F ²)] = 0.048
wR(F ²) = 0.113
S = 1.10
3424 reflections
193 parameters
H-atom parameters constrained
Δρ_max = 0.72 e Å⁻³
Δρ_min = −0.41 e Å⁻³

Data collection: COLLECT (Nonius, 1998 ▶); cell refinement: COLLECT; data reduction: DENZO (Otwinowski & Minor, 1997 ▶); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: ORTEP-3 (Farrugia, 1997 ▶); software used to prepare material for publication: publCIF (Westrip, 2010 ▶).

Supplementary Material

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536810035142/ng5014sup1.cif

e-66-o2479-sup1.cif^{(18.3KB, cif)}

Structure factors: contains datablocks I. DOI: 10.1107/S1600536810035142/ng5014Isup2.hkl

e-66-o2479-Isup2.hkl^{(168KB, hkl)}

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Table 1. Hydrogen-bond geometry (Å, °).

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C3—H3⋯O3ⁱ	0.95	2.53	3.227 (3)	130
C12—H12⋯O1ⁱⁱ	0.95	2.55	3.441 (3)	157
C14—H14A⋯O3ⁱⁱⁱ	0.98	2.53	3.474 (3)	161
C15—H15B⋯Cl1^iv	0.98	2.82	3.647 (3)	142

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Symmetry codes: (i) Inline graphic ; (ii) ; (iii) ; (iv) .

Acknowledgments

CSC thanks the University of Mysore for providing research facilities. HSY thanks the University of Mysore for sanctioning sabbatical leave.

supplementary crystallographic information

Comment

The title compound, (I), (Fig. 1), was prepared as part of our ongoing structural studies (Jasinski et al., 2010) of chalcone-like compounds, in which substituted aromatic ring systems are linked by a prop-2-en-1-one bridge.

The prop-2-en-1-one fragment in (I) is almost planar [C7—C8—C9—O3 = 2.2 (4)°] and it subtends dihedral angles of 11.9 (2) and 11.0 (2)° with the thiophene and benzene rings, respectively. The dihedral angle between the aromatic rings is 3.47 (16)°. The carbon atoms of the methoxy groups are close to co-planar with their attached benzene ring [displacements of 0.033 (5) and 0.100 (5)Å for C14 and C15, respectively]. Otherwise, the bond lengths for (I) fall within their expected ranges (Allen et al., 1987) and are similar to those in a related structure (Jasinski et al., 2010).

In the crystal, three weak C—H···O and one C—H···Cl interactions (Table 1) link the molecules. Considered individually, they generate the following motifs: the C3—H3 bond generates inversion dimers containing R₂²(14) rings, whereas the C12—H12 bond leads to C(11) chains propagating in [010]. The methyl-H bonds lead to inversion-generated R₂²(24) loops (for C15—H15B) and C(11) chains (for C14—H14A). Taken together, these four interactions generate a three-dimensional network. Weak aromatic π-π stacking [centroid-centroid separations = 3.6823 (15) and 3.8722 (15) Å] may also help to consolidate the packing.

Experimental

2,5-Dichloro-3-acetylthiophene was obtained as a gift sample from SeQuent Scientific ltd., New Mangalore, India. 1-(2,5-Dichlorothiophen-3-yl)ethanone (1.95 g, 0.01 mol) was mixed with 3,4-dimethoxybenzaldehyde (1.66 g, 0.01 mol) and dissolved in ethanol (30 ml). To this, 3 ml of 50% KOH was added. The reaction mixture was stirred for 6 h. The resulting crude solid was filtered, washed successively with distilled water and finally recrystallized from ethanol (95%) to give the pure chalcone. Irregular yellow crystals of (I) were obtained by the slow evaporation of DMF solution (m.p.: 389–391 K).