(Z)-1-(2,5-Dichloro-3-thien­yl)ethanone semicarbazone

Fun, H.-K.; Quah, C.K.; Vijesh, A.M.; Hegde, C.; Isloor, A.M.

doi:10.1107/S1600536809026567

organic compounds

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ISSN: 2056-9890

Volume 65| Part 8| August 2009| Pages o1852-o1853

doi:10.1107/S1600536809026567

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(Z)-1-(2,5-Dichloro-3-thienyl)ethanone semicarbazone

Hoong-Kun Fun,^a ^*‡ Ching Kheng Quah,^a § A. M. Vijesh,^b ¶ Chitrakar Hegde ^c and Arun M. Isloor ^d

^aX-ray Crystallography Unit, School of Physics, Universiti Sains Malaysia, 11800 USM, Penang, Malaysia, ^bSeQuent Scientific Limited, No. 120 A&B, Industrial Area, Baikampady, New Mangalore, Karnataka 575 011, India, ^cDepartment of Chemistry, NITTE Institute of Technology, Yelahanka, Bangalore 560 064, India, and ^dDepartment of Chemistry, National Institute of Technology-Karnataka, Surathkal, Mangalore 575 025, India
^*Correspondence e-mail: hkfun@usm.my

(Received 7 July 2009; accepted 8 July 2009; online 15 July 2009)

The title molecule, C₇H₇Cl₂N₃OS, is approximately planar [maximum deviation = 0.062 (1) Å]. Short intermolecular distances between the centroids of the five-membered rings [3.5340 (8) Å] indicate the existence of π–π interactions. An interesting feature of the crystal structure is the presence of short intramolecular Cl⋯N interactions [3.0015 (11) Å]. Molecules are linked via pairs of intermolecular N—H⋯O hydrogen bonds, generating R₂²(8) ring motifs. Furthermore, N—H⋯O hydrogen bonds form R₂¹(7) ring motifs with C—H⋯O contacts, further consolidating the crystal structure. In the crystal, molecules are linked by these intermolecular interactions, forming chains along [001].

Related literature

For the synthetic utility and applications of semicarbazone derivatives, see: Warren et al. (1977 ); Chandra & Gupta (2005 ); Jain et al. (2002 ); Pilgram (1978 ); Yogeeswari et al. (2004 ). For related structures, see: Fun et al. (2009a ,b ). For the preparation, see: Furniss et al. (1978 ). For hydrogen-bond motifs, see: Bernstein et al. (1995 ). For the stability of the temperature controller used for the data collection, see: Cosier & Glazer (1986 ).

Experimental

Crystal data

C₇H₇Cl₂N₃OS
M_r = 252.12
Monoclinic, C 2/c
a = 13.0796 (2) Å
b = 10.4316 (2) Å
c = 14.4352 (2) Å
β = 94.599 (1)°
V = 1963.21 (6) Å³
Z = 8
Mo Kα radiation
μ = 0.84 mm⁻¹
T = 100 K
0.49 × 0.22 × 0.08 mm

Data collection

Bruker SMART APEXII CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2005 ) T_min = 0.683, T_max = 0.934
16375 measured reflections
3742 independent reflections
3060 reflections with I > 2σ(I)
R_int = 0.029

Refinement

R[F² > 2σ(F²)] = 0.034
wR(F²) = 0.100
S = 1.13
3742 reflections
140 parameters
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.46 e Å⁻³
Δρ_min = −0.35 e Å⁻³

Table 1
Selected interatomic distance (Å)

Cg1⋯Cg1ⁱ	3.7188 (6)
Symmetry code: (i) $[x+{\script{5\over 2}}, y+{\script{1\over 2}}, z+1]$ . Cg1 is the centroid of the S1/C3–C6 five-membered ring.

Table 2
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N1—H1N1⋯O1ⁱⁱ	0.86 (2)	2.02 (2)	2.8766 (15)	177.3 (19)
N2—H1N2⋯O1ⁱⁱⁱ	0.863 (19)	2.035 (19)	2.8949 (14)	174.2 (17)
C7—H7A⋯O1ⁱⁱⁱ	0.96	2.38	3.3370 (17)	176
Symmetry codes: (ii) $[-x+1, y, -z+{\script{1\over 2}}]$ ; (iii) -x+1, -y, -z+1.

Data collection: APEX2 (Bruker, 2005); cell refinement: SAINT (Bruker, 2005); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008 ); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL and PLATON (Spek, 2009 ).

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536809026567/tk2498sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536809026567/tk2498Isup2.hkl

checkCIF report

Comment top

Semicarbazones find immense applications in the field of synthetic chemistry, such as medicinal chemistry (Warren et al., 1977), organometallics (Chandra & Gupta, 2005), polymers (Jain et al., 2002) and herbicides (Pilgram, 1978). Futher, 4-sulphamoylphenyl semicarbazones were found to possess anti-convulsant activity (Yogeeswari et al., 2004). Herein, we report the crystal structure of the title semicarbazone (I).

The bond lengths and angles in (I), Fig. 1, are comparable to those observed in two closely related structures (Fun et al., 2009a, b). The molecule is approximately planar, with an r.m.s. deviation of 0.062 (1) Å for atom O1. The short intramolecular distances between the centroids of five-membered rings [3.5340 (8) Å] prove existence of π–π interactions (Table 1). The interesting feature of the crystal structure is the short intermolecular Cl···N interactions [3.0015 (11) Å]".

The molecules are linked via pairs of intermolecular N1—H1N1···O1 and N2—H1N2···O1 (Table 2) hydrogen bonds to generate R₂²(8) ring motifs (Bernstein et al., 1995) (Fig. 2). Furthermore, N2—H1N2···O1 hydrogen bonds form R₂¹(7) ring motifs with C7—H7A···O1 contacts to further consolidate the crystal structure. The molecules are linked by these intermolecular interactions to form 1-D chains along the [0 0 1] direction.

Related literature top

For the synthetic utility and applications of semicarbazone derivatives, see: Warren et al. (1977); Chandra & Gupta (2005); Jain et al. (2002); Pilgram (1978); Yogeeswari et al. (2004). For related structures, see: Fun et al. (2009a,b). For the preparation, see: Furniss et al. (1978). For hydrogen-bond motifs, see: Bernstein et al. (1995). For the stability of the temperature controller used for the data collection, see: Cosier & Glazer (1986). Cg1 is the centroid of the S1/C3–C6 five-membered ring.

Experimental top

Semicarbazide hydrochloride (1.84 g, 16.5 mmol) and freshly recrystallized sodium acetate (1.64 g, 20.0 mmol) was dissolved in water (15 ml) according to a literature procedure (Furniss et al., 1978). The reaction mixture was stirred at room temperature for 10 minutes. To this, 2,5-dichloro-3-acetylthiophene (3.0 g, 15.4 mmol) in ethanol (15 ml) was added and stirred well for 6 h. The separated semicarbazone was filtered, washed with chilled water and recrystallized from an ethanol/dimethylformamide mixture. Yield: 3.19 g, 82.22%. M.p. 491–493 K.

Computing details top

Data collection: APEX2 (Bruker, 2005); cell refinement: SAINT (Bruker, 2005); data reduction: SAINT (Bruker, 2005); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).

Figures top

	Fig. 1. The molecular structure of (I), showing 50% probability displacement ellipsoids and the atom-numbering scheme.
	Fig. 2. The crystal packing in (I), viewed along the b axis. The dashed lines indicate hydrogen bonds and C-H···O contacts.

(Z)-1-(2,5-Dichloro-3-thienyl)ethanone semicarbazone top

Crystal data top

C₇H₇Cl₂N₃OS	F(000) = 1024
M_r = 252.12	D_x = 1.706 Mg m⁻³
Monoclinic, C2/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2yc	Cell parameters from 6313 reflections
a = 13.0796 (2) Å	θ = 2.5–33.2°
b = 10.4316 (2) Å	µ = 0.84 mm⁻¹
c = 14.4352 (2) Å	T = 100 K
β = 94.599 (1)°	Plate, colourless
V = 1963.21 (6) Å³	0.49 × 0.22 × 0.08 mm
Z = 8

Data collection top

Bruker SMART APEXII CCD area-detector diffractometer	3742 independent reflections
Radiation source: fine-focus sealed tube	3060 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.029
ϕ and ω scans	θ_max = 33.2°, θ_min = 2.5°
Absorption correction: multi-scan (SADABS; Bruker, 2005)	h = −20→19
T_min = 0.683, T_max = 0.934	k = −16→15
16375 measured reflections	l = −22→22

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F² > 2σ(F²)] = 0.034	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.100	H atoms treated by a mixture of independent and constrained refinement
S = 1.13	w = 1/[σ²(F_o²) + (0.0516P)² + 0.6332P] where P = (F_o² + 2F_c²)/3
3742 reflections	(Δ/σ)_max = 0.002
140 parameters	Δρ_max = 0.46 e Å⁻³
0 restraints	Δρ_min = −0.35 e Å⁻³

Crystal data top

C₇H₇Cl₂N₃OS	V = 1963.21 (6) Å³
M_r = 252.12	Z = 8
Monoclinic, C2/c	Mo Kα radiation
a = 13.0796 (2) Å	µ = 0.84 mm⁻¹
b = 10.4316 (2) Å	T = 100 K
c = 14.4352 (2) Å	0.49 × 0.22 × 0.08 mm
β = 94.599 (1)°

Data collection top

Bruker SMART APEXII CCD area-detector diffractometer	3742 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2005)	3060 reflections with I > 2σ(I)
T_min = 0.683, T_max = 0.934	R_int = 0.029
16375 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.034	0 restraints
wR(F²) = 0.100	H atoms treated by a mixture of independent and constrained refinement
S = 1.13	Δρ_max = 0.46 e Å⁻³
3742 reflections	Δρ_min = −0.35 e Å⁻³
140 parameters

Special details top

Experimental. The crystal was placed in the cold stream of an Oxford Cyrosystems Cobra open-flow nitrogen cryostat (Cosier & Glazer, 1986) operating at 100.0 (1) K.

Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'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 > σ(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 (Å²) top

	x	y	z	U_iso*/U_eq
Cl1	1.17736 (3)	0.23231 (4)	0.62567 (3)	0.02794 (10)
Cl2	0.88955 (3)	0.12728 (4)	0.31571 (2)	0.02421 (10)
S1	1.06944 (2)	0.19596 (3)	0.43833 (3)	0.01940 (9)
O1	0.48318 (7)	−0.00827 (9)	0.37962 (6)	0.01622 (18)
N1	0.62401 (10)	0.02718 (15)	0.30045 (8)	0.0247 (3)
N2	0.63508 (8)	0.03704 (11)	0.46052 (7)	0.0150 (2)
N3	0.73470 (8)	0.07286 (10)	0.45321 (7)	0.0146 (2)
C1	0.57608 (9)	0.01731 (12)	0.37865 (8)	0.0147 (2)
C2	0.79348 (9)	0.09889 (12)	0.52643 (9)	0.0141 (2)
C3	0.89959 (10)	0.13686 (12)	0.51073 (9)	0.0150 (2)
C4	0.97547 (10)	0.16495 (13)	0.58619 (9)	0.0183 (2)
H4A	0.9621	0.1617	0.6485	0.022*
C5	1.06803 (10)	0.19643 (13)	0.55714 (10)	0.0194 (3)
C6	0.94260 (10)	0.15031 (13)	0.42725 (9)	0.0167 (2)
C7	0.76299 (11)	0.09363 (16)	0.62397 (9)	0.0232 (3)
H7A	0.6913	0.0734	0.6234	0.035*
H7B	0.7757	0.1753	0.6533	0.035*
H7C	0.8024	0.0288	0.6579	0.035*
H1N1	0.5931 (16)	0.0142 (19)	0.2466 (16)	0.036 (5)*
H2N1	0.6797 (17)	0.0442 (19)	0.3063 (14)	0.030 (5)*
H1N2	0.6027 (14)	0.0324 (17)	0.5102 (13)	0.022 (4)*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Cl1	0.01347 (16)	0.0327 (2)	0.0365 (2)	−0.00378 (13)	−0.00478 (14)	−0.00720 (15)
Cl2	0.01543 (15)	0.0411 (2)	0.01659 (15)	−0.00354 (13)	0.00432 (11)	0.00003 (12)
S1	0.01115 (15)	0.02034 (16)	0.02707 (17)	−0.00210 (11)	0.00391 (12)	0.00104 (12)
O1	0.0101 (4)	0.0251 (5)	0.0135 (4)	−0.0015 (4)	0.0005 (3)	0.0007 (3)
N1	0.0116 (5)	0.0502 (8)	0.0124 (5)	−0.0061 (5)	0.0008 (4)	−0.0013 (5)
N2	0.0102 (4)	0.0224 (5)	0.0122 (4)	−0.0034 (4)	0.0008 (4)	−0.0002 (4)
N3	0.0095 (4)	0.0199 (5)	0.0148 (4)	−0.0027 (4)	0.0018 (4)	−0.0003 (4)
C1	0.0121 (5)	0.0185 (6)	0.0136 (5)	−0.0006 (4)	0.0020 (4)	−0.0001 (4)
C2	0.0113 (5)	0.0156 (5)	0.0152 (5)	−0.0010 (4)	0.0010 (4)	−0.0004 (4)
C3	0.0113 (5)	0.0154 (5)	0.0182 (5)	−0.0006 (4)	0.0006 (4)	−0.0008 (4)
C4	0.0137 (6)	0.0199 (6)	0.0208 (6)	−0.0011 (5)	−0.0010 (5)	−0.0029 (5)
C5	0.0121 (5)	0.0195 (6)	0.0261 (6)	−0.0011 (5)	−0.0020 (5)	−0.0041 (5)
C6	0.0117 (5)	0.0192 (6)	0.0192 (6)	−0.0010 (5)	0.0016 (4)	0.0000 (4)
C7	0.0164 (6)	0.0390 (8)	0.0140 (5)	−0.0029 (6)	0.0005 (5)	−0.0002 (5)

Geometric parameters (Å, º) top

Cl1—C5	1.7137 (14)	N3—C2	1.2851 (16)
Cl2—C6	1.7182 (13)	C2—C3	1.4782 (18)
S1—C5	1.7167 (15)	C2—C7	1.4949 (18)
S1—C6	1.7211 (13)	C3—C6	1.3773 (19)
O1—C1	1.2452 (15)	C3—C4	1.4436 (18)
N1—C1	1.3384 (17)	C4—C5	1.3530 (19)
N1—H1N1	0.86 (2)	C4—H4A	0.9300
N1—H2N1	0.75 (2)	C7—H7A	0.9600
N2—N3	1.3677 (15)	C7—H7B	0.9600
N2—C1	1.3741 (16)	C7—H7C	0.9600
N2—H1N2	0.863 (19)

Cg1···Cg1ⁱ	3.7188 (6)	Cl2···N3	3.0015 (11)

C5—S1—C6	90.35 (6)	C4—C3—C2	122.41 (12)
C1—N1—H1N1	122.3 (14)	C5—C4—C3	113.17 (13)
C1—N1—H2N1	116.2 (16)	C5—C4—H4A	123.4
H1N1—N1—H2N1	122 (2)	C3—C4—H4A	123.4
N3—N2—C1	116.57 (10)	C4—C5—Cl1	126.87 (12)
N3—N2—H1N2	127.8 (12)	C4—C5—S1	112.98 (10)
C1—N2—H1N2	115.3 (12)	Cl1—C5—S1	120.14 (8)
C2—N3—N2	120.34 (11)	C3—C6—Cl2	130.02 (10)
O1—C1—N1	123.33 (12)	C3—C6—S1	113.90 (10)
O1—C1—N2	120.24 (11)	Cl2—C6—S1	116.08 (8)
N1—C1—N2	116.44 (11)	C2—C7—H7A	109.5
N3—C2—C3	115.96 (11)	C2—C7—H7B	109.5
N3—C2—C7	125.43 (11)	H7A—C7—H7B	109.5
C3—C2—C7	118.61 (11)	C2—C7—H7C	109.5
C6—C3—C4	109.59 (11)	H7A—C7—H7C	109.5
C6—C3—C2	128.00 (12)	H7B—C7—H7C	109.5

C1—N2—N3—C2	176.77 (12)	C3—C4—C5—Cl1	−178.46 (10)
N3—N2—C1—O1	−175.87 (11)	C3—C4—C5—S1	0.65 (16)
N3—N2—C1—N1	4.15 (18)	C6—S1—C5—C4	−0.70 (11)
N2—N3—C2—C3	−179.86 (11)	C6—S1—C5—Cl1	178.47 (9)
N2—N3—C2—C7	0.1 (2)	C4—C3—C6—Cl2	179.02 (11)
N3—C2—C3—C6	1.5 (2)	C2—C3—C6—Cl2	−0.5 (2)
C7—C2—C3—C6	−178.55 (13)	C4—C3—C6—S1	−0.35 (15)
N3—C2—C3—C4	−177.95 (12)	C2—C3—C6—S1	−179.82 (10)
C7—C2—C3—C4	2.03 (19)	C5—S1—C6—C3	0.60 (11)
C6—C3—C4—C5	−0.19 (17)	C5—S1—C6—Cl2	−178.86 (9)
C2—C3—C4—C5	179.32 (12)

Symmetry code: (i) x+5/2, y+1/2, z+1.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1N1···O1ⁱⁱ	0.86 (2)	2.02 (2)	2.8766 (15)	177.3 (19)
N2—H1N2···O1ⁱⁱⁱ	0.863 (19)	2.035 (19)	2.8949 (14)	174.2 (17)
C7—H7A···O1ⁱⁱⁱ	0.96	2.38	3.3370 (17)	176

Symmetry codes: (ii) −x+1, y, −z+1/2; (iii) −x+1, −y, −z+1.

Experimental details

Crystal data
Chemical formula	C₇H₇Cl₂N₃OS
M_r	252.12
Crystal system, space group	Monoclinic, C2/c
Temperature (K)	100
a, b, c (Å)	13.0796 (2), 10.4316 (2), 14.4352 (2)
β (°)	94.599 (1)
V (Å³)	1963.21 (6)
Z	8
Radiation type	Mo Kα
µ (mm⁻¹)	0.84
Crystal size (mm)	0.49 × 0.22 × 0.08

Data collection
Diffractometer	Bruker SMART APEXII CCD area-detector diffractometer
Absorption correction	Multi-scan (SADABS; Bruker, 2005)
T_min, T_max	0.683, 0.934
No. of measured, independent and observed [I > 2σ(I)] reflections	16375, 3742, 3060
R_int	0.029
(sin θ/λ)_max (Å⁻¹)	0.770

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.034, 0.100, 1.13
No. of reflections	3742
No. of parameters	140
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.46, −0.35

Computer programs: APEX2 (Bruker, 2005), SAINT (Bruker, 2005), SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).

Selected interatomic distances (Å) top

Cg1···Cg1ⁱ

3.7188 (6)

Cl2···N3

3.0015 (11)

Symmetry code: (i) x+5/2, y+1/2, z+1.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1N1···O1ⁱⁱ	0.86 (2)	2.02 (2)	2.8766 (15)	177.3 (19)
N2—H1N2···O1ⁱⁱⁱ	0.863 (19)	2.035 (19)	2.8949 (14)	174.2 (17)
C7—H7A···O1ⁱⁱⁱ	0.96	2.38	3.3370 (17)	176.1

Symmetry codes: (ii) −x+1, y, −z+1/2; (iii) −x+1, −y, −z+1.

Footnotes

‡Thomson Reuters ResearcherID: A-3561-2009.

§Thomson Reuters ResearcherID: A-5525-2009.

¶Current address: Department of Chemistry, National Institute of Technology-Karnataka, Surathkal, Mangalore 575 025, India.

Acknowledgements

HKF and CKQ thank Universiti Sains Malaysia (USM) for the Research University Golden Goose Grant (No. 1001/PFIZIK/811012). CKQ thanks USM for a Research Fellowship. AMI is grateful to the Head of the Department of Chemistry and the Director, NITK, Surathkal, India, for providing research facilities.

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