(E)-1-(2,5-Dichloro-3-thien­yl)-3-[4-(dimethyl­amino)phen­yl]prop-2-en-1-one

In the title compound, C₁₅H₁₃Cl₂NOS, the benzene and thio­phene rings make a dihedral angle of 10.8 (1)°. The dimethyl­amino substituent and the α,β-unsaturated carbonyl group are almost coplanar with respect to the aromatic ring, forming dihedral angles of 4.73 (3)° and 5.0 (2)°, respectively. In the crystal structure, mol­ecules are connected into two-dimensional layers by weak C—H...Cl hydrogen bonds and C—Cl...O [Cl...O = 3.073 (2) Å] inter­actions. These layers are stacked with short C(meth­yl)–H...π contacts betweeen the layers.

Key indicators

• Single-crystal X-ray study
• T = 295 K
• Mean [sigma](C-C) = 0.003 Å
• R factor = 0.038
• wR factor = 0.109
• Data-to-parameter ratio = 17.1

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT431_ALERT_2_C Short Inter HL..A Contact  Cl2    ..  O6      ..       3.07 Ang.
PLAT910_ALERT_3_C Missing # of FCF Reflections Below Th(Min) .....          1
PLAT152_ALERT_1_C The Supplied and Calc. Volume s.u. Differ by ...         -3 Units
PLAT480_ALERT_4_C Long H...A H-Bond Reported H16A   ..  C~G~    ..       3.01 Ang.
PLAT716_ALERT_1_C H...A   Unknown or Inconsistent Label ..........       C~G~
                    H16A   C~G~
PLAT717_ALERT_1_C D...A   Unknown or Inconsistent Label ..........       C~G~
                    C16    C~G~
PLAT718_ALERT_1_C D-H..A  Unknown or Inconsistent Label ..........       C~G~
                    C16    H16A   C~G~
PLAT912_ALERT_4_C Missing # of FCF Reflections Above STh/L=  0.600        553

   0 ALERT level A = In general: serious problem
   0 ALERT level B = Potentially serious problem
   8 ALERT level C = Check and explain
   0 ALERT level G = General alerts; check

   4 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   1 ALERT type 2 Indicator that the structure model may be wrong or deficient
   1 ALERT type 3 Indicator that the structure quality may be low
   2 ALERT type 4 Improvement, methodology, query or suggestion
   0 ALERT type 5 Informative message, check

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S1. Comment

Chalcones derivatives are known for their interesting pharmacological activities. Radical quenching properties of the phenolic groups present in many chalcones have raised interest in using the compounds themselves or chalcone rich plant extracts as drugs or food preservatives. Apart from being biologically important compounds, chalcone derivatives show non-linear optical properties with excellent blue light transmittance and good crystallizability (Indira et al., 2002; Sarojini et al., 2006). They provide a necessary configuration to show NLO property with two planar rings connected by a conjugated double bond. Synthesis and antimicrobial evaluation of new chalcones containing a 2,5-dichlorothiophene moiety is reported (Tomar et al., 2007). Here, we report the synthesis and crystal structure of the new chalcone derivative, (2E)-1-(2,5-dichlorothiophen-3-yl)-3-(4-dimethylamino-phenyl)prop-2-en-1-one (I, Scheme 1) .

The molecule as a whole does not deviate significantly from planarity (Fig. 1). Dihedral angles between the constituent planar fragments are relatively small. The two ring planes of the phenyl and thiophene groups make a dihedral angle of 10.8 (1)°. The dimethylamino substituent and the α,β-unsaturated carbonyl moeity are inclined with respect to the phenyl ring plane by 4.73 (3)° and 5.0 (2)°, respectively. The bond lengths pattern within the C(=O)—C=C- fragment shows significant conjugation with shorter formal single bonds compared to formal double bonds that are longer than typical values.

In the crystal structure an intermolecular C–H···Cl hydrogen bond (H···Cl distance 2.72 Å, C–H···Cl angle 168°) and C—Cl···O interactions connect the molecules into approximately planar layers parallel to (101) (Fig. 2). The chlorine oxygen interaction also is almost linear (C2–Cl2···O6 angle of 167.6 (8)°) and relatively short (Cl2···O6 3.073 (2) Å). These layers are stacked on each other showing additional intermolecular C–H···π interactions with H16A···Cg distance of 3.01Å (Cg is the centroid of the phenyl ring).

Related literature

For applications of chalcone derivatives, see: Indira et al. (2002); Sarojini et al. (2006); Tomar et al. (2007).

S2. Experimental

1-(2,5-Dichlorothiophen-3-yl)ethanone (1.95 g, 0.01 mol) was mixed with 4-dimethylamino)-benzaldehyde (1.49 g, 0.01 mol) and dissolved in ethanol (30 ml). 3 ml of KOH (50%) was added to this solution. The reaction mixture was stirred for 6 hours. The resulting crude solid was filtered, washed successively with distilled water and finally recrystallized from ethanol (95%) to give the pure chalcone. Crystals suitable for x-ray diffraction studies were grown by slow evaporation of solution in toluene (M.P.: 358 K).

S3. Refinement

H atoms were placed in idealized positions and constrained to ride on their parent atoms, with C–H = 0.93 Å and U_iso(H) = 1.2 U_eq(C) for phenyl hydrogen and olefinic CH groups and with 0.96 Å and U_iso(H) = 1.5 U_eq(C) for CH₃ groups.

Computing details

Data collection: CrysAlis PRO (Oxford Diffraction, 2009); cell refinement: CrysAlis PRO (Oxford Diffraction, 2009); data reduction: CrysAlis PRO (Oxford Diffraction, 2009); program(s) used to solve structure: SIR92 (Altomare et al., 1993); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997) and Mercury (Macrae et al., 2008); software used to prepare material for publication: Stereochemical Workstation Operation Manual (Siemens, 1989) and SHELXL97 (Sheldrick, 2008).

Figures

	Fig. 1. Molecular structure of (I), showing 50% probability displacement ellipsoids and the atom-numbering scheme.
	Fig. 2. Crystal packing of (I) viewed along the b axis. C–H···Cl hydrogen bonds and C—Cl···O interactions are shown as dashed lines.
	Fig. 3. C–H···π interactions in the stack of molecules (I).

(E)-1-(2,5-Dichloro-3-thienyl)-3-[4-(dimethylamino)phenyl]prop-2-en-1-one

Crystal data

C15H13Cl2NOS	Z = 2
Mr = 326.22	F(000) = 336
Triclinic, P1	Dx = 1.450 Mg m^−3
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 7.2637 (9) Å	Cell parameters from 5611 reflections
b = 8.1136 (9) Å	θ = 2.6–28.2°
c = 13.478 (2) Å	µ = 0.57 mm^−1
α = 89.011 (9)°	T = 295 K
β = 79.71 (1)°	Block, yellow
γ = 73.07 (1)°	0.6 × 0.3 × 0.3 mm
V = 747.2 (2) Å^3

Data collection

Oxford Diffraction Xcalibur diffractometer with an Eos detector	3152 independent reflections
Radiation source: Enhance (Mo) X-ray Source	2403 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.018
Detector resolution: 16.1544 pixels mm^-1	θmax = 28.3°, θmin = 2.6°
ω scan	h = −9→9
Absorption correction: multi-scan (CrysAlis PRO; Oxford Diffraction, 2009)	k = −10→10
Tmin = 0.785, Tmax = 1.000	l = −17→17
8710 measured reflections

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.038	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.109	H-atom parameters constrained
S = 1.10	w = 1/[σ^2(Fo^2) + (0.0546P)^2 + 0.1725P] where P = (Fo^2 + 2Fc^2)/3
3152 reflections	(Δ/σ)max = 0.001
184 parameters	Δρmax = 0.37 e Å^−3
0 restraints	Δρmin = −0.40 e Å^−3

Special details

Geometry. All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'s involving l.s. planes.

Refinement. Refinement of F² against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F², conventional R-factors R are based on F, with F set to zero for negative F². The threshold expression of F² > 2σ(F²) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F² are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
S1	0.67788 (8)	0.11979 (8)	1.11606 (4)	0.05238 (18)
Cl2	0.49256 (8)	0.25700 (9)	0.94627 (4)	0.0620 (2)
C2	0.6887 (3)	0.2294 (3)	1.00611 (14)	0.0407 (4)
C3	0.8555 (3)	0.2780 (2)	0.98033 (14)	0.0383 (4)
C4	0.9777 (3)	0.2234 (3)	1.05438 (15)	0.0431 (5)
H4A	1.0980	0.2443	1.0507	0.052*
Cl5	1.00237 (10)	0.05512 (9)	1.23148 (4)	0.0699 (2)
C5	0.9014 (3)	0.1398 (3)	1.12908 (15)	0.0454 (5)
C6	0.9255 (3)	0.3667 (3)	0.89011 (15)	0.0432 (5)
O6	1.0970 (2)	0.3669 (2)	0.87491 (13)	0.0636 (5)
C7	0.7927 (3)	0.4499 (3)	0.82226 (16)	0.0473 (5)
H7A	0.6621	0.4519	0.8378	0.057*
C8	0.8548 (3)	0.5232 (3)	0.73845 (16)	0.0456 (5)
H8A	0.9845	0.5242	0.7283	0.055*
C9	0.7452 (3)	0.6010 (2)	0.66156 (15)	0.0412 (4)
C10	0.5490 (3)	0.6086 (3)	0.66361 (15)	0.0435 (5)
H10A	0.4820	0.5665	0.7188	0.052*
C11	0.4534 (3)	0.6765 (3)	0.58656 (15)	0.0435 (5)
H11A	0.3233	0.6795	0.5908	0.052*
C12	0.5478 (3)	0.7420 (2)	0.50101 (14)	0.0399 (4)
C13	0.7440 (3)	0.7332 (3)	0.49862 (16)	0.0489 (5)
H13A	0.8125	0.7735	0.4432	0.059*
C14	0.8364 (3)	0.6662 (3)	0.57683 (16)	0.0500 (5)
H14A	0.9662	0.6641	0.5731	0.060*
N15	0.4527 (3)	0.8088 (2)	0.42422 (14)	0.0527 (5)
C16	0.2469 (4)	0.8283 (3)	0.4313 (2)	0.0669 (7)
H16A	0.2267	0.7165	0.4308	0.100*
H16B	0.2015	0.8906	0.3749	0.100*
H16C	0.1756	0.8906	0.4929	0.100*
C17	0.5519 (4)	0.8642 (4)	0.33356 (17)	0.0657 (7)
H17A	0.5962	0.9594	0.3497	0.098*
H17B	0.4636	0.8996	0.2868	0.098*
H17C	0.6623	0.7707	0.3037	0.098*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
S1	0.0501 (3)	0.0691 (4)	0.0431 (3)	−0.0253 (3)	−0.0097 (2)	0.0124 (3)
Cl2	0.0468 (3)	0.0961 (5)	0.0581 (4)	−0.0360 (3)	−0.0242 (3)	0.0189 (3)
C2	0.0371 (10)	0.0488 (11)	0.0378 (10)	−0.0123 (9)	−0.0117 (8)	0.0027 (8)
C3	0.0376 (10)	0.0399 (10)	0.0387 (10)	−0.0103 (8)	−0.0124 (8)	0.0024 (8)
C4	0.0383 (10)	0.0475 (12)	0.0464 (11)	−0.0125 (9)	−0.0160 (9)	0.0042 (9)
Cl5	0.0750 (4)	0.0881 (5)	0.0490 (3)	−0.0178 (3)	−0.0300 (3)	0.0209 (3)
C5	0.0479 (11)	0.0516 (12)	0.0372 (10)	−0.0104 (9)	−0.0162 (9)	0.0060 (9)
C6	0.0400 (10)	0.0458 (11)	0.0467 (11)	−0.0139 (9)	−0.0138 (9)	0.0059 (9)
O6	0.0461 (9)	0.0881 (12)	0.0681 (11)	−0.0317 (8)	−0.0226 (8)	0.0325 (9)
C7	0.0437 (11)	0.0525 (12)	0.0500 (12)	−0.0165 (10)	−0.0170 (9)	0.0138 (10)
C8	0.0436 (11)	0.0482 (12)	0.0490 (12)	−0.0165 (9)	−0.0139 (9)	0.0072 (9)
C9	0.0448 (11)	0.0398 (11)	0.0408 (10)	−0.0144 (9)	−0.0091 (8)	0.0057 (8)
C10	0.0447 (11)	0.0474 (12)	0.0389 (10)	−0.0165 (9)	−0.0046 (8)	0.0086 (9)
C11	0.0382 (10)	0.0496 (12)	0.0436 (11)	−0.0148 (9)	−0.0078 (8)	0.0083 (9)
C12	0.0451 (11)	0.0370 (10)	0.0379 (10)	−0.0119 (8)	−0.0085 (8)	0.0044 (8)
C13	0.0474 (12)	0.0568 (13)	0.0456 (12)	−0.0226 (10)	−0.0054 (9)	0.0145 (10)
C14	0.0404 (11)	0.0612 (14)	0.0528 (13)	−0.0217 (10)	−0.0098 (9)	0.0138 (10)
N15	0.0540 (11)	0.0618 (12)	0.0466 (10)	−0.0205 (9)	−0.0163 (8)	0.0205 (8)
C16	0.0601 (15)	0.0778 (17)	0.0707 (16)	−0.0228 (13)	−0.0302 (13)	0.0236 (13)
C17	0.0734 (17)	0.0800 (17)	0.0454 (13)	−0.0247 (14)	−0.0132 (12)	0.0191 (12)

Geometric parameters (Å, º)

S1—C2	1.717 (2)	C10—C11	1.371 (3)
S1—C5	1.717 (2)	C10—H10A	0.9300
Cl2—C2	1.7175 (19)	C11—C12	1.411 (3)
C2—C3	1.366 (3)	C11—H11A	0.9300
C3—C4	1.433 (3)	C12—N15	1.364 (3)
C3—C6	1.489 (3)	C12—C13	1.401 (3)
C4—C5	1.333 (3)	C13—C14	1.371 (3)
C4—H4A	0.9300	C13—H13A	0.9300
Cl5—C5	1.718 (2)	C14—H14A	0.9300
C6—O6	1.226 (2)	N15—C17	1.439 (3)
C6—C7	1.462 (3)	N15—C16	1.443 (3)
C7—C8	1.335 (3)	C16—H16A	0.9600
C7—H7A	0.9300	C16—H16B	0.9600
C8—C9	1.444 (3)	C16—H16C	0.9600
C8—H8A	0.9300	C17—H17A	0.9600
C9—C14	1.391 (3)	C17—H17B	0.9600
C9—C10	1.403 (3)	C17—H17C	0.9600
C2—S1—C5	89.86 (10)	C10—C11—C12	121.54 (19)
C3—C2—S1	113.70 (14)	C10—C11—H11A	119.2
C3—C2—Cl2	130.86 (16)	C12—C11—H11A	119.2
S1—C2—Cl2	115.43 (11)	N15—C12—C13	121.88 (18)
C2—C3—C4	110.04 (18)	N15—C12—C11	121.47 (19)
C2—C3—C6	130.73 (17)	C13—C12—C11	116.65 (18)
C4—C3—C6	119.18 (17)	C14—C13—C12	120.89 (19)
C5—C4—C3	113.12 (18)	C14—C13—H13A	119.6
C5—C4—H4A	123.4	C12—C13—H13A	119.6
C3—C4—H4A	123.4	C13—C14—C9	123.04 (19)
C4—C5—S1	113.29 (15)	C13—C14—H14A	118.5
C4—C5—Cl5	127.12 (17)	C9—C14—H14A	118.5
S1—C5—Cl5	119.59 (13)	C12—N15—C17	121.73 (19)
O6—C6—C7	121.58 (19)	C12—N15—C16	121.05 (19)
O6—C6—C3	117.89 (17)	C17—N15—C16	117.22 (19)
C7—C6—C3	120.54 (17)	N15—C16—H16A	109.5
C8—C7—C6	121.49 (19)	N15—C16—H16B	109.5
C8—C7—H7A	119.3	H16A—C16—H16B	109.5
C6—C7—H7A	119.3	N15—C16—H16C	109.5
C7—C8—C9	127.96 (19)	H16A—C16—H16C	109.5
C7—C8—H8A	116.0	H16B—C16—H16C	109.5
C9—C8—H8A	116.0	N15—C17—H17A	109.5
C14—C9—C10	116.05 (18)	N15—C17—H17B	109.5
C14—C9—C8	120.06 (18)	H17A—C17—H17B	109.5
C10—C9—C8	123.80 (18)	N15—C17—H17C	109.5
C11—C10—C9	121.81 (18)	H17A—C17—H17C	109.5
C11—C10—H10A	119.1	H17B—C17—H17C	109.5
C9—C10—H10A	119.1
C5—S1—C2—C3	0.36 (17)	C6—C7—C8—C9	176.1 (2)
C5—S1—C2—Cl2	179.45 (13)	C7—C8—C9—C14	−177.7 (2)
S1—C2—C3—C4	−0.3 (2)	C7—C8—C9—C10	−1.0 (4)
Cl2—C2—C3—C4	−179.25 (16)	C14—C9—C10—C11	0.0 (3)
S1—C2—C3—C6	176.89 (17)	C8—C9—C10—C11	−176.8 (2)
Cl2—C2—C3—C6	−2.0 (4)	C9—C10—C11—C12	0.1 (3)
C2—C3—C4—C5	0.1 (3)	C10—C11—C12—N15	179.72 (19)
C6—C3—C4—C5	−177.47 (18)	C10—C11—C12—C13	0.3 (3)
C3—C4—C5—S1	0.1 (2)	N15—C12—C13—C14	179.7 (2)
C3—C4—C5—Cl5	−179.88 (15)	C11—C12—C13—C14	−0.9 (3)
C2—S1—C5—C4	−0.28 (18)	C12—C13—C14—C9	1.0 (4)
C2—S1—C5—Cl5	179.74 (14)	C10—C9—C14—C13	−0.5 (3)
C2—C3—C6—O6	−166.3 (2)	C8—C9—C14—C13	176.4 (2)
C4—C3—C6—O6	10.7 (3)	C13—C12—N15—C17	4.0 (3)
C2—C3—C6—C7	13.5 (3)	C11—C12—N15—C17	−175.4 (2)
C4—C3—C6—C7	−169.47 (18)	C13—C12—N15—C16	−175.5 (2)
O6—C6—C7—C8	3.0 (3)	C11—C12—N15—C16	5.2 (3)
C3—C6—C7—C8	−176.8 (2)

Hydrogen-bond geometry (Å, º)

Cg is the centroid of the phenyl ring.

D—H···A	D—H	H···A	D···A	D—H···A
C16—H16B···Cl5^i	0.96	2.72	3.664 (2)	168
C16—H16A···Cg^ii	0.96	3.01	3.899 (3)	155

Symmetry codes: (i) x−1, y+1, z−1; (ii) −x+1, −y+1, −z+1.