N,N'-Bis[1-(thiophen-2-yl)ethylidene]ethane-1,2-diamine

Mol­ecules of the title compound, C₁₄H₁₆N₂S₂, have a centre of inversion in the middle of the -CH₂-CH₂- bond; the (C₄H₃S)(CH₃)C=N-CH₂- moiety is almost planar (r.m.s. deviation for non-H atoms 0.027 Å).

Key indicators

• Single-crystal X-ray study
• T = 100 K
• Mean [sigma](C-C) = 0.003 Å
• R factor = 0.035
• wR factor = 0.090
• Data-to-parameter ratio = 18.0

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT029_ALERT_3_C _diffrn_measured_fraction_theta_full Low .......      0.965
PLAT912_ALERT_4_C Missing # of FCF Reflections Above STh/L=  0.600         55

Alert level G
PLAT005_ALERT_5_G No _iucr_refine_instructions_details in CIF ....          ?
PLAT128_ALERT_4_G Alternate Setting of Space-group P21/c   .......      P21/n

   0 ALERT level A = Most likely a serious problem - resolve or explain
   0 ALERT level B = A potentially serious problem, consider carefully
   2 ALERT level C = Check. Ensure it is not caused by an omission or oversight
   2 ALERT level G = General information/check it is not something unexpected

   0 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
   1 ALERT type 3 Indicator that the structure quality may be low
   2 ALERT type 4 Improvement, methodology, query or suggestion
   1 ALERT type 5 Informative message, check

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S1. Comment

A large number of transition metal adducts of Schiff bases derived by condensing ethylenediamine with a ketone have been reported; in these adducts, the ligand typically functions in a chelating mode. However, there are few studies on the title Schiff base (Scheme I), and only one crystal structure study has been reported (Modder et al., 1995). The C₁₄H₁₆N₂S₂ molecule lies on a center-of-inversion (Fig. 1); the (C₄H₃S)(CH₃)C═ N–CH₂– moiety is planar, and the chain connecting the two aromatic rings adopts an extended zigzag conformation [C═N–C–C 88.1 (2)°].

Related literature

For a related transition metal adduct, see: Modder et al. (1995).

S2. Experimental

Ethylenediamine (0.6 g, 10 mmol) and 2-acetylthiophene (0.7 g, 10 mmol) in dry benzene (50 ml) were refluxed in a Dean–Stark apparatus until no more water was collected (in about 2 h). The solvent was removed and the solid that separated was collected and recystallized from ethanol.

S3. Refinement

H-atoms were placed in calculated positions [C—H 0.95–0.98 Å, U_iso(H) = 1.2–1.5U_eq(C)] and were included in the refinement in the riding model approximation.

Computing details

Data collection: CrysAlis PRO (Agilent, 2010); cell refinement: CrysAlis PRO (Agilent, 2010); data reduction: CrysAlis PRO (Agilent, 2010); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: X-SEED (Barbour, 2001); software used to prepare material for publication: publCIF (Westrip, 2010).

Figures

Fig. 1. Anisotropic displacement ellipsoid plot (Barbour, 2001) of C14H16N2S2 at the 70% probability level; H atoms are drawn as spheres of arbitrary radius. The molecule lies on a center-of-inversion.

N,N'-Bis[1-(thiophen-2-yl)ethylidene]ethane-1,2-diamine

Crystal data

C14H16N2S2	F(000) = 292
Mr = 276.41	Dx = 1.361 Mg m^−3
Monoclinic, P21/n	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2yn	Cell parameters from 1562 reflections
a = 5.5831 (3) Å	θ = 2.7–29.1°
b = 9.3939 (4) Å	µ = 0.38 mm^−1
c = 12.9202 (5) Å	T = 100 K
β = 95.342 (4)°	Prism, colourless
V = 674.68 (5) Å^3	0.25 × 0.20 × 0.15 mm
Z = 2

Data collection

Agilent SuperNova Dual diffractometer with Atlas detector	1495 independent reflections
Radiation source: SuperNova (Mo) X-ray Source	1244 reflections with I > 2σ(I)
Mirror monochromator	Rint = 0.028
Detector resolution: 10.4041 pixels mm^-1	θmax = 27.5°, θmin = 2.7°
ω scans	h = −5→7
Absorption correction: multi-scan (CrysAlis PRO; Agilent, 2010)	k = −12→9
Tmin = 0.912, Tmax = 0.946	l = −16→16
3036 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)] = 0.035	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.090	H-atom parameters constrained
S = 1.04	w = 1/[σ^2(Fo^2) + (0.0323P)^2 + 0.5515P] where P = (Fo^2 + 2Fc^2)/3
1495 reflections	(Δ/σ)max = 0.001
83 parameters	Δρmax = 0.44 e Å^−3
0 restraints	Δρmin = −0.40 e Å^−3

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

	x	y	z	Uiso*/Ueq
S1	0.66665 (8)	0.89024 (5)	0.29153 (3)	0.01547 (15)
N1	0.5827 (3)	0.68042 (16)	0.45253 (11)	0.0141 (3)
C1	0.5756 (4)	0.56063 (19)	0.52477 (14)	0.0163 (4)
H1A	0.5065	0.5926	0.5887	0.020*
H1B	0.7412	0.5264	0.5446	0.020*
C2	0.4204 (3)	0.77676 (19)	0.44907 (13)	0.0122 (4)
C3	0.2062 (3)	0.7852 (2)	0.51239 (14)	0.0168 (4)
H3A	0.0574	0.7795	0.4659	0.025*
H3B	0.2102	0.8756	0.5503	0.025*
H3C	0.2120	0.7060	0.5619	0.025*
C4	0.4397 (3)	0.89283 (18)	0.37376 (13)	0.0113 (4)
C5	0.2995 (3)	1.0123 (2)	0.35677 (14)	0.0144 (4)
H5	0.1648	1.0330	0.3940	0.017*
C6	0.3775 (3)	1.1021 (2)	0.27724 (14)	0.0163 (4)
H6	0.3017	1.1893	0.2561	0.020*
C7	0.5731 (4)	1.0482 (2)	0.23535 (13)	0.0171 (4)
H7	0.6491	1.0930	0.1812	0.021*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
S1	0.0182 (3)	0.0134 (3)	0.0156 (2)	0.00002 (19)	0.00604 (18)	0.00080 (18)
N1	0.0170 (8)	0.0116 (7)	0.0135 (7)	−0.0028 (7)	0.0004 (6)	0.0025 (6)
C1	0.0195 (10)	0.0134 (9)	0.0154 (8)	−0.0006 (8)	−0.0007 (7)	0.0034 (8)
C2	0.0132 (9)	0.0120 (9)	0.0111 (8)	−0.0033 (7)	−0.0008 (7)	−0.0025 (7)
C3	0.0148 (9)	0.0213 (10)	0.0147 (8)	−0.0010 (8)	0.0030 (7)	0.0010 (8)
C4	0.0118 (8)	0.0118 (9)	0.0102 (8)	−0.0018 (7)	0.0006 (6)	−0.0013 (7)
C5	0.0131 (9)	0.0150 (9)	0.0151 (8)	0.0000 (8)	0.0007 (7)	−0.0015 (7)
C6	0.0185 (10)	0.0134 (9)	0.0156 (8)	0.0012 (8)	−0.0055 (7)	0.0013 (7)
C7	0.0239 (10)	0.0146 (9)	0.0123 (8)	−0.0052 (8)	−0.0006 (7)	0.0019 (7)

Geometric parameters (Å, º)

S1—C7	1.712 (2)	C3—H3A	0.9800
S1—C4	1.7278 (17)	C3—H3B	0.9800
N1—C2	1.279 (2)	C3—H3C	0.9800
N1—C1	1.465 (2)	C4—C5	1.375 (2)
C1—C1^i	1.523 (4)	C5—C6	1.428 (3)
C1—H1A	0.9900	C5—H5	0.9500
C1—H1B	0.9900	C6—C7	1.361 (3)
C2—C4	1.472 (2)	C6—H6	0.9500
C2—C3	1.513 (2)	C7—H7	0.9500
C7—S1—C4	92.09 (9)	H3A—C3—H3C	109.5
C2—N1—C1	120.31 (15)	H3B—C3—H3C	109.5
N1—C1—C1^i	110.72 (18)	C5—C4—C2	129.41 (16)
N1—C1—H1A	109.5	C5—C4—S1	110.65 (13)
C1^i—C1—H1A	109.5	C2—C4—S1	119.94 (13)
N1—C1—H1B	109.5	C4—C5—C6	112.95 (16)
C1^i—C1—H1B	109.5	C4—C5—H5	123.5
H1A—C1—H1B	108.1	C6—C5—H5	123.5
N1—C2—C4	116.88 (15)	C7—C6—C5	112.08 (17)
N1—C2—C3	127.72 (16)	C7—C6—H6	124.0
C4—C2—C3	115.39 (16)	C5—C6—H6	124.0
C2—C3—H3A	109.5	C6—C7—S1	112.24 (14)
C2—C3—H3B	109.5	C6—C7—H7	123.9
H3A—C3—H3B	109.5	S1—C7—H7	123.9
C2—C3—H3C	109.5
C2—N1—C1—C1^i	88.1 (2)	C7—S1—C4—C5	0.05 (14)
C1—N1—C2—C4	−179.53 (15)	C7—S1—C4—C2	−179.44 (14)
C1—N1—C2—C3	−0.6 (3)	C2—C4—C5—C6	179.10 (17)
N1—C2—C4—C5	−176.62 (18)	S1—C4—C5—C6	−0.3 (2)
C3—C2—C4—C5	4.3 (3)	C4—C5—C6—C7	0.5 (2)
N1—C2—C4—S1	2.8 (2)	C5—C6—C7—S1	−0.5 (2)
C3—C2—C4—S1	−176.34 (13)	C4—S1—C7—C6	0.25 (15)

Symmetry code: (i) −x+1, −y+1, −z+1.