1-(2,4-Dichloro­benzyl­idene)-4-ethyl­thio­semicarbazide

The title compound, C₁₀H₁₁Cl₂N₃S, was prepared by the reaction of 4-ethyl­thio­semicarbazide and 2,4-dichloro­benzaldehyde. It is approximately planar, the dihedral angle between the benzene ring and the thio­urea unit being 8.43 (18)°. In the crystal, inversion dimers linked by pairs of N—H...S hydrogen bonds generate R₂²(8) loops.

Key indicators

• Single-crystal X-ray study
• T = 293 K
• Mean [sigma](C-C) = 0.007 Å
• R factor = 0.060
• wR factor = 0.187
• Data-to-parameter ratio = 18.7

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT029_ALERT_3_C _diffrn_measured_fraction_theta_full Low .......       0.96
PLAT340_ALERT_3_C Low Bond Precision on  C-C Bonds (x 1000) Ang ..          7
PLAT910_ALERT_3_C Missing # of FCF Reflections Below Th(Min) .....          3
PLAT911_ALERT_3_C Missing # FCF Refl Between THmin & STh/L=  0.600         72
PLAT912_ALERT_4_C Missing # of FCF Reflections Above STh/L=  0.600         28

Alert level G
PLAT128_ALERT_4_G Alternate Setting of Space-group P21/c   .......      P21/n
PLAT199_ALERT_1_G Check the Reported _cell_measurement_temperature        293 K
PLAT200_ALERT_1_G Check the Reported   _diffrn_ambient_temperature        293 K

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

   2 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   0 ALERT type 2 Indicator that the structure model may be wrong or deficient
   4 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

Schiff-base have attracted much attention because they can be utilized as effective ligands to be coordination compounds in coordination chemistry. (Casas et al., 2000). As part of our research for new Schiff-base compounds we synthesized the title compound (I), and describe its structure here. In the molecule structure, the dihedral angle between the benzene ring and the thiourea unit is [8.43 (18)°].

Bond lengths and angles agree with those observed in a related structure (Li & Jian, 2010).

Related literature

For background to Schiff bases, see: Casas et al. (2000). For a related structure, see: Li & Jian (2010).

S2. Experimental

A mixture of 4-ethylthiosemicarbazide (0.1 mol) and 2,4-dichlorobenzaldehyde (0.1 mol) was stirred in refluxing ethanol (30 mL) for 2 h to afford the title compound (0.090 mol, yield 90%). Colourless blocks of (I) were obtained by recrystallization from ethanol at room temperature.

S3. Refinement

H atoms were fixed geometrically and allowed to ride on their attached atoms, with C—H distances=0.97 Å, and with U_iso=1.2–1.5U_eq.

Computing details

Data collection: SMART (Bruker, 1997); cell refinement: SAINT (Bruker, 1997); data reduction: SAINT (Bruker, 1997); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures

Fig. 1. The structure of (I) showing 30% probability displacement ellipsoids.

1-(2,4-Dichlorobenzylidene)-4-ethylthiosemicarbazide

Crystal data

C10H11Cl2N3S	F(000) = 568
Mr = 276.18	Dx = 1.486 Mg m^−3
Monoclinic, P21/n	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2yn	Cell parameters from 1416 reflections
a = 5.4339 (11) Å	θ = 3.5–27.5°
b = 20.526 (4) Å	µ = 0.67 mm^−1
c = 11.313 (2) Å	T = 293 K
β = 101.97 (3)°	Block, colorless
V = 1234.4 (4) Å^3	0.22 × 0.20 × 0.18 mm
Z = 4

Data collection

Bruker SMART CCD diffractometer	1416 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	Rint = 0.109
Graphite monochromator	θmax = 27.5°, θmin = 3.5°
phi and ω scans	h = −6→6
10913 measured reflections	k = −26→26
2707 independent reflections	l = −14→14

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)] = 0.060	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.187	H-atom parameters constrained
S = 0.92	w = 1/[σ^2(Fo^2) + (0.1P)^2] where P = (Fo^2 + 2Fc^2)/3
2707 reflections	(Δ/σ)max < 0.001
145 parameters	Δρmax = 0.37 e Å^−3
0 restraints	Δρmin = −0.35 e Å^−3

Special details

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 (Ų)

	x	y	z	Uiso*/Ueq
S1	−0.1063 (2)	0.99987 (6)	0.79802 (13)	0.0434 (4)
Cl2	0.7303 (2)	0.85591 (6)	1.34950 (13)	0.0499 (4)
Cl1	1.4115 (2)	0.70212 (6)	1.20880 (15)	0.0558 (4)
N3	0.4756 (6)	0.90330 (15)	0.9707 (4)	0.0355 (9)
N2	0.2667 (7)	0.94274 (17)	0.9454 (4)	0.0390 (9)
H2A	0.2030	0.9583	1.0029	0.047*
N1	0.2795 (7)	0.93533 (18)	0.7450 (4)	0.0410 (10)
H1A	0.4117	0.9118	0.7681	0.049*
C5	0.7795 (7)	0.84768 (18)	1.1156 (4)	0.0317 (10)
C3	0.1623 (7)	0.95672 (19)	0.8288 (4)	0.0324 (10)
C8	1.1713 (8)	0.7596 (2)	1.1742 (5)	0.0381 (11)
C9	1.0643 (8)	0.78286 (19)	1.2644 (5)	0.0393 (12)
H9A	1.1209	0.7695	1.3440	0.047*
C4	0.5640 (8)	0.89200 (19)	1.0829 (5)	0.0373 (11)
H4A	0.4932	0.9114	1.1423	0.045*
C7	1.0936 (9)	0.7793 (2)	1.0562 (5)	0.0418 (12)
H7A	1.1715	0.7632	0.9964	0.050*
C10	0.8684 (8)	0.82717 (19)	1.2342 (4)	0.0332 (10)
C6	0.8994 (8)	0.8232 (2)	1.0276 (5)	0.0384 (11)
H6A	0.8471	0.8368	0.9480	0.046*
C2	0.2011 (10)	0.9487 (3)	0.6169 (5)	0.0492 (13)
H2B	0.2201	0.9949	0.6029	0.059*
H2C	0.0246	0.9377	0.5906	0.059*
C1	0.3510 (11)	0.9109 (3)	0.5440 (6)	0.0641 (16)
H1B	0.2935	0.9209	0.4599	0.096*
H1C	0.3306	0.8651	0.5567	0.096*
H1D	0.5255	0.9223	0.5686	0.096*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
S1	0.0362 (7)	0.0577 (7)	0.0350 (8)	0.0114 (4)	0.0044 (5)	0.0005 (5)
Cl2	0.0628 (8)	0.0614 (7)	0.0280 (8)	0.0123 (5)	0.0151 (6)	0.0009 (6)
Cl1	0.0561 (8)	0.0551 (7)	0.0546 (11)	0.0202 (5)	0.0078 (7)	0.0014 (6)
N3	0.037 (2)	0.0394 (19)	0.030 (3)	0.0028 (13)	0.0062 (17)	0.0035 (16)
N2	0.039 (2)	0.051 (2)	0.026 (3)	0.0122 (15)	0.0047 (17)	0.0013 (17)
N1	0.037 (2)	0.054 (2)	0.030 (3)	0.0091 (15)	0.0019 (18)	0.0029 (18)
C5	0.039 (2)	0.030 (2)	0.025 (3)	−0.0023 (15)	0.0038 (19)	0.0018 (17)
C3	0.031 (2)	0.040 (2)	0.026 (3)	−0.0020 (16)	0.0043 (19)	−0.0015 (18)
C8	0.040 (2)	0.038 (2)	0.034 (3)	0.0015 (17)	0.003 (2)	−0.0022 (19)
C9	0.045 (3)	0.041 (2)	0.029 (3)	0.0050 (17)	−0.001 (2)	0.0030 (19)
C4	0.038 (2)	0.042 (2)	0.030 (3)	0.0049 (17)	0.004 (2)	−0.0011 (19)
C7	0.045 (3)	0.047 (2)	0.035 (3)	0.0042 (18)	0.012 (2)	−0.007 (2)
C10	0.041 (2)	0.037 (2)	0.022 (3)	0.0003 (16)	0.0089 (19)	−0.0005 (18)
C6	0.045 (3)	0.047 (2)	0.023 (3)	0.0012 (18)	0.005 (2)	−0.003 (2)
C2	0.055 (3)	0.066 (3)	0.025 (3)	0.011 (2)	0.004 (2)	0.004 (2)
C1	0.057 (3)	0.099 (4)	0.038 (4)	0.015 (3)	0.013 (3)	−0.004 (3)

Geometric parameters (Å, º)

S1—C3	1.681 (4)	C8—C7	1.376 (7)
Cl2—C10	1.738 (5)	C9—C10	1.388 (6)
Cl1—C8	1.743 (4)	C9—H9A	0.9300
N3—C4	1.282 (6)	C4—H4A	0.9300
N3—N2	1.375 (5)	C7—C6	1.373 (6)
N2—C3	1.354 (6)	C7—H7A	0.9300
N2—H2A	0.8600	C6—H6A	0.9300
N1—C3	1.322 (6)	C2—C1	1.491 (7)
N1—C2	1.449 (7)	C2—H2B	0.9700
N1—H1A	0.8600	C2—H2C	0.9700
C5—C6	1.392 (7)	C1—H1B	0.9600
C5—C10	1.393 (6)	C1—H1C	0.9600
C5—C4	1.468 (6)	C1—H1D	0.9600
C8—C9	1.362 (7)
C4—N3—N2	115.8 (4)	C6—C7—C8	119.2 (5)
C3—N2—N3	119.2 (4)	C6—C7—H7A	120.4
C3—N2—H2A	120.4	C8—C7—H7A	120.4
N3—N2—H2A	120.4	C9—C10—C5	122.1 (4)
C3—N1—C2	124.7 (4)	C9—C10—Cl2	117.8 (4)
C3—N1—H1A	117.7	C5—C10—Cl2	120.2 (3)
C2—N1—H1A	117.7	C7—C6—C5	121.3 (5)
C6—C5—C10	117.3 (4)	C7—C6—H6A	119.3
C6—C5—C4	120.7 (4)	C5—C6—H6A	119.3
C10—C5—C4	121.9 (4)	N1—C2—C1	111.9 (4)
N1—C3—N2	117.5 (4)	N1—C2—H2B	109.2
N1—C3—S1	123.6 (4)	C1—C2—H2B	109.2
N2—C3—S1	118.9 (4)	N1—C2—H2C	109.2
C9—C8—C7	122.1 (4)	C1—C2—H2C	109.2
C9—C8—Cl1	119.0 (4)	H2B—C2—H2C	107.9
C7—C8—Cl1	118.8 (4)	C2—C1—H1B	109.5
C8—C9—C10	118.0 (5)	C2—C1—H1C	109.5
C8—C9—H9A	121.0	H1B—C1—H1C	109.5
C10—C9—H9A	121.0	C2—C1—H1D	109.5
N3—C4—C5	118.5 (5)	H1B—C1—H1D	109.5
N3—C4—H4A	120.8	H1C—C1—H1D	109.5
C5—C4—H4A	120.8

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N2—H2A···S1^i	0.86	2.56	3.409 (5)	168

Symmetry code: (i) −x, −y+2, −z+2.