Diethyl 2,5-bis­[(E)-thio­phen-2-ylmethyl­eneamino]thio­phene-3,4-dicarboxyl­ate

In the mol­ecule of the highly conjugated title compound, C₂₀H₁₈N₂O₄S₃, the thio­phene rings are in an anti­parallel arrangement and both azomethine bonds adopt the thermodynamically stable E isomeric form. The mean planes of the terminal thio­phene rings are twisted by 9.04 (4) and 25.07 (6)° from the mean plane of the azomethine groups and the central thio­phene ring.

Key indicators

• Single-crystal X-ray study
• T = 293 K
• Mean [sigma](C-C) = 0.005 Å
• R factor = 0.043
• wR factor = 0.114
• Data-to-parameter ratio = 15.6

checkCIF/PLATON results

No syntax errors found





Alert level C
GOODF01_ALERT_2_C  The least squares goodness of fit parameter lies
            outside the range 0.80 <> 2.00
            Goodness of fit given =      0.728
PLAT026_ALERT_3_C Ratio Observed / Unique Reflections too Low ....         42 Perc.
PLAT220_ALERT_2_C Large Non-Solvent    C     Ueq(max)/Ueq(min) ...       2.88 Ratio
PLAT222_ALERT_3_C Large Non-Solvent    H     Ueq(max)/Ueq(min) ...       3.30 Ratio
PLAT241_ALERT_2_C Check High      Ueq as Compared to Neighbors for        C13
PLAT242_ALERT_2_C Check Low       Ueq as Compared to Neighbors for        C15
PLAT340_ALERT_3_C Low Bond Precision on C-C bonds (x 1000) Ang ...          5
PLAT360_ALERT_2_C Short  C(sp3)-C(sp3) Bond  C16    -   C17    ...       1.43 Ang.
PLAT360_ALERT_2_C Short  C(sp3)-C(sp3) Bond  C19    -   C20    ...       1.41 Ang.

Alert level G
ABSTM02_ALERT_3_G  The ratio of expected to reported Tmax/Tmin(RR') is < 0.90
            Tmin and Tmax reported:      0.160     0.650
            Tmin(prime) and Tmax expected:      0.192     0.624
            RR(prime) =      0.802
            Please check that your absorption correction is appropriate.
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
   9 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
   6 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
   0 ALERT type 4 Improvement, methodology, query or suggestion
   0 ALERT type 5 Informative message, check

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Computing details

Data collection: CAD-4 Software (Enraf–Nonius, 1989); cell refinement: CAD-4 Software; data reduction: local program; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SHELXTL (Bruker, 1997); software used to prepare material for publication: UdMX (Marris, 2004).

Diethyl 2,5-Bis[(E)-thiophen-2-ylmethyleneamino]thiophene-3,4-dicarboxylate

Crystal data

C20H18N2O4S3	F(000) = 1856
Mr = 446.54	Dx = 1.364 Mg m^−3
Orthorhombic, Pbcn	Cu Kα radiation, λ = 1.54178 Å
Hall symbol: -P 2n 2ab	Cell parameters from 25 reflections
a = 17.039 (5) Å	θ = 15.0–20.0°
b = 18.642 (8) Å	µ = 3.36 mm^−1
c = 13.690 (4) Å	T = 293 K
V = 4349 (3) Å^3	Block, red
Z = 8	0.44 × 0.35 × 0.14 mm

Data collection

Enraf–Nonius CAD-4 diffractometer	1716 reflections with I > 2σ(I)
Radiation source: X-ray sealed tube	Rint = 0.091
Graphite monochromator	θmax = 70.0°, θmin = 3.5°
ω scans	h = −20→20
Absorption correction: gaussian Gaussian from crystal shape	k = −22→22
Tmin = 0.160, Tmax = 0.650	l = −16→16
32236 measured reflections	4 standard reflections every 60 min
4130 independent reflections	intensity decay: −0.1%

Refinement

Refinement on F^2	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F^2 > 2σ(F^2)] = 0.043	H-atom parameters constrained
wR(F^2) = 0.114	w = 1/[σ^2(Fo^2) + (0.0464P)^2]
S = 0.73	(Δ/σ)max = 0.001
4130 reflections	Δρmax = 0.22 e Å^−3
265 parameters	Δρmin = −0.24 e Å^−3
0 restraints	Extinction correction: SHELXL97, Fc^*=kFc[1+0.001xFc^2λ^3/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.00082 (4)

Special details

Experimental. X-ray crystallographic data for I were collected from a single-crystal sample, which was mounted on a glass fiber. Data were collected using an Enraf–Nonius CAD4 diffractometer equipped with FR590 generator, a Kappa goniometer, a standard scintillation counter and a locally modified low temperature device. The initial unit-cell parameters were determined by a least-squares fit of the angular setting of 25 strong reflections. The intensity of some selected strong reflections was monitored during the course of the data collection. Data were corrected for absorption, Lorentz and polarization effects

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	−0.03111 (5)	0.11395 (4)	0.61847 (7)	0.0674 (3)
S2	0.00949 (6)	0.41302 (5)	0.60391 (9)	0.0949 (4)
S3	−0.01209 (6)	−0.19013 (5)	0.61949 (8)	0.0931 (4)
O1	0.19644 (14)	0.23862 (15)	0.7010 (2)	0.1199 (12)
O2	0.24756 (13)	0.15498 (12)	0.60495 (19)	0.0898 (8)
O3	0.21389 (14)	0.01777 (14)	0.7283 (2)	0.0987 (9)
O4	0.19320 (14)	−0.02071 (14)	0.5763 (2)	0.0961 (9)
N1	0.03035 (15)	0.25076 (14)	0.6266 (2)	0.0664 (7)
N2	0.01697 (16)	−0.02824 (13)	0.62567 (19)	0.0662 (7)
C1	0.04322 (17)	0.17684 (16)	0.6311 (2)	0.0618 (8)
C2	0.11562 (18)	0.14548 (17)	0.6390 (2)	0.0618 (9)
C3	0.11123 (18)	0.06926 (17)	0.6355 (2)	0.0623 (9)
C4	0.03605 (18)	0.04369 (16)	0.6258 (2)	0.0626 (8)
C5	−0.0385 (2)	0.27501 (17)	0.6431 (2)	0.0672 (9)
H5	−0.0783	0.2426	0.6580	0.081*
C6	−0.05722 (18)	0.35027 (16)	0.6395 (3)	0.0669 (9)
C7	−0.1273 (2)	0.38096 (18)	0.6650 (3)	0.0813 (11)
H7	−0.1708	0.3553	0.6865	0.098*
C8	−0.1256 (2)	0.4560 (2)	0.6547 (3)	0.0979 (13)
H8	−0.1681	0.4856	0.6686	0.117*
C9	−0.0559 (2)	0.48015 (19)	0.6225 (3)	0.1013 (14)
H9	−0.0448	0.5283	0.6116	0.122*
C10	−0.0543 (2)	−0.04751 (17)	0.6269 (2)	0.0725 (10)
H10	−0.0928	−0.0122	0.6284	0.087*
C11	−0.0785 (2)	−0.12178 (17)	0.6261 (3)	0.0725 (10)
C12	−0.1547 (2)	−0.1460 (2)	0.6302 (3)	0.0968 (13)
H12	−0.1986	−0.1166	0.6347	0.116*
C13	−0.1572 (3)	−0.2209 (2)	0.6266 (4)	0.1198 (17)
H13	−0.2036	−0.2471	0.6284	0.144*
C14	−0.0854 (3)	−0.2513 (2)	0.6202 (3)	0.1052 (14)
H14	−0.0772	−0.3006	0.6167	0.126*
C15	0.1890 (2)	0.18586 (19)	0.6522 (3)	0.0752 (11)
C16	0.3258 (2)	0.1833 (2)	0.6175 (3)	0.1137 (16)
H16A	0.3425	0.2068	0.5578	0.136*
H16B	0.3258	0.2187	0.6694	0.136*
C17	0.3795 (2)	0.1267 (2)	0.6412 (4)	0.162 (2)
H17A	0.3673	0.1081	0.7048	0.243*
H17B	0.4321	0.1450	0.6410	0.243*
H17C	0.3749	0.0891	0.5937	0.243*
C18	0.1788 (2)	0.01971 (19)	0.6534 (3)	0.0719 (10)
C19	0.2535 (3)	−0.0759 (2)	0.5909 (4)	0.141 (2)
H19A	0.3040	−0.0535	0.6027	0.169*
H19B	0.2404	−0.1052	0.6471	0.169*
C20	0.2572 (3)	−0.1189 (2)	0.5062 (4)	0.178 (3)
H20A	0.2093	−0.1456	0.4996	0.267*
H20B	0.3006	−0.1515	0.5114	0.267*
H20C	0.2642	−0.0888	0.4500	0.267*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
S1	0.0555 (4)	0.0622 (5)	0.0845 (6)	0.0017 (4)	−0.0021 (5)	−0.0020 (5)
S2	0.0786 (6)	0.0730 (6)	0.1331 (10)	−0.0024 (5)	0.0198 (7)	0.0105 (7)
S3	0.1059 (8)	0.0717 (6)	0.1018 (9)	−0.0006 (6)	0.0003 (7)	0.0034 (6)
O1	0.0670 (16)	0.103 (2)	0.190 (3)	−0.0108 (15)	0.0076 (18)	−0.072 (2)
O2	0.0554 (13)	0.0844 (17)	0.130 (2)	−0.0027 (13)	0.0139 (16)	−0.0280 (16)
O3	0.0881 (19)	0.0992 (19)	0.109 (2)	0.0251 (16)	−0.0260 (17)	−0.0080 (18)
O4	0.0826 (17)	0.0826 (17)	0.123 (2)	0.0265 (15)	−0.0030 (16)	−0.0278 (17)
N1	0.0625 (16)	0.0599 (15)	0.077 (2)	0.0068 (14)	0.0027 (16)	−0.0033 (15)
N2	0.0666 (17)	0.0587 (16)	0.0732 (19)	−0.0052 (13)	−0.0021 (16)	−0.0037 (15)
C1	0.0581 (19)	0.0589 (19)	0.068 (2)	0.0037 (16)	0.0037 (18)	−0.0045 (18)
C2	0.0583 (19)	0.0573 (19)	0.070 (2)	0.0009 (16)	0.0007 (18)	−0.0065 (18)
C3	0.0592 (19)	0.060 (2)	0.067 (2)	0.0035 (16)	0.0022 (18)	−0.0089 (18)
C4	0.0603 (19)	0.060 (2)	0.068 (2)	0.0002 (17)	0.0007 (18)	−0.0050 (18)
C5	0.065 (2)	0.063 (2)	0.074 (3)	0.0012 (17)	−0.001 (2)	0.0023 (18)
C6	0.0555 (19)	0.060 (2)	0.085 (3)	0.0063 (16)	0.0003 (18)	0.0042 (19)
C7	0.068 (2)	0.063 (2)	0.113 (3)	0.0093 (19)	0.008 (2)	0.009 (2)
C8	0.096 (3)	0.070 (3)	0.128 (4)	0.027 (2)	0.019 (3)	0.012 (3)
C9	0.103 (3)	0.059 (2)	0.142 (4)	0.009 (2)	0.024 (3)	0.011 (3)
C10	0.069 (2)	0.064 (2)	0.084 (3)	−0.0013 (18)	0.002 (2)	−0.005 (2)
C11	0.076 (2)	0.063 (2)	0.080 (3)	−0.0081 (18)	0.005 (2)	−0.003 (2)
C12	0.083 (3)	0.074 (3)	0.134 (4)	−0.024 (2)	0.010 (3)	−0.020 (3)
C13	0.109 (4)	0.101 (4)	0.149 (5)	−0.037 (3)	0.025 (4)	−0.018 (3)
C14	0.147 (4)	0.069 (3)	0.099 (4)	−0.032 (3)	0.011 (3)	−0.004 (2)
C15	0.059 (2)	0.064 (2)	0.102 (3)	0.0023 (19)	0.006 (2)	−0.013 (2)
C16	0.059 (2)	0.105 (3)	0.177 (5)	−0.014 (2)	0.017 (3)	−0.026 (3)
C17	0.076 (3)	0.111 (4)	0.298 (8)	0.007 (3)	−0.030 (4)	−0.002 (4)
C18	0.062 (2)	0.061 (2)	0.092 (3)	0.0026 (18)	−0.001 (2)	−0.003 (2)
C19	0.114 (3)	0.126 (4)	0.182 (5)	0.073 (3)	−0.021 (4)	−0.049 (4)
C20	0.183 (5)	0.119 (4)	0.232 (8)	0.069 (4)	−0.010 (5)	−0.059 (4)

Geometric parameters (Å, º)

S1—C1	1.734 (3)	C7—H7	0.93
S1—C4	1.742 (3)	C8—C9	1.344 (5)
S2—C9	1.695 (4)	C8—H8	0.93
S2—C6	1.702 (3)	C9—H9	0.93
S3—C14	1.692 (4)	C10—C11	1.445 (4)
S3—C11	1.707 (3)	C10—H10	0.93
O1—C15	1.196 (4)	C11—C12	1.376 (4)
O2—C15	1.321 (4)	C12—C13	1.397 (5)
O2—C16	1.445 (4)	C12—H12	0.93
O3—C18	1.188 (4)	C13—C14	1.351 (5)
O4—C18	1.320 (4)	C13—H13	0.93
O4—C19	1.468 (4)	C14—H14	0.93
N1—C5	1.278 (3)	C16—C17	1.433 (5)
N1—C1	1.397 (3)	C16—H16a	0.97
N2—C10	1.266 (4)	C16—H16b	0.97
N2—C4	1.380 (3)	C17—H17a	0.96
C1—C2	1.369 (4)	C17—H17b	0.96
C2—C3	1.424 (4)	C17—H17c	0.96
C2—C15	1.471 (4)	C19—C20	1.411 (5)
C3—C4	1.373 (4)	C19—H19a	0.97
C3—C18	1.496 (4)	C19—H19b	0.97
C5—C6	1.439 (4)	C20—H20a	0.96
C5—H5	0.93	C20—H20b	0.96
C6—C7	1.370 (4)	C20—H20c	0.96
C7—C8	1.406 (4)
C1—S1—C4	91.31 (15)	C11—C12—C13	110.8 (4)
C9—S2—C6	91.45 (17)	C11—C12—H12	124.6
C14—S3—C11	90.8 (2)	C13—C12—H12	124.6
C15—O2—C16	118.7 (3)	C14—C13—C12	113.2 (4)
C18—O4—C19	114.9 (3)	C14—C13—H13	123.4
C5—N1—C1	119.1 (3)	C12—C13—H13	123.4
C10—N2—C4	120.1 (3)	C13—C14—S3	112.7 (3)
C2—C1—N1	124.5 (3)	C13—C14—H14	123.7
C2—C1—S1	112.2 (2)	S3—C14—H14	123.7
N1—C1—S1	123.2 (2)	O1—C15—O2	123.5 (3)
C1—C2—C3	112.1 (3)	O1—C15—C2	125.4 (3)
C1—C2—C15	123.9 (3)	O2—C15—C2	111.1 (3)
C3—C2—C15	124.0 (3)	C17—C16—O2	110.3 (3)
C4—C3—C2	113.5 (3)	C17—C16—H16A	109.6
C4—C3—C18	121.3 (3)	O2—C16—H16A	109.6
C2—C3—C18	124.8 (3)	C17—C16—H16B	109.6
C3—C4—N2	123.9 (3)	O2—C16—H16B	109.6
C3—C4—S1	110.9 (2)	H16A—C16—H16B	108.1
N2—C4—S1	125.2 (2)	C16—C17—H17A	109.5
N1—C5—C6	122.8 (3)	C16—C17—H17B	109.5
N1—C5—H5	118.6	H17A—C17—H17B	109.5
C6—C5—H5	118.6	C16—C17—H17C	109.5
C7—C6—C5	126.3 (3)	H17A—C17—H17C	109.5
C7—C6—S2	111.6 (3)	H17B—C17—H17C	109.5
C5—C6—S2	122.1 (3)	O3—C18—O4	125.4 (4)
C6—C7—C8	111.8 (3)	O3—C18—C3	123.2 (4)
C6—C7—H7	124.1	O4—C18—C3	111.4 (3)
C8—C7—H7	124.1	C20—C19—O4	108.5 (4)
C9—C8—C7	112.6 (3)	C20—C19—H19A	110
C9—C8—H8	123.7	O4—C19—H19A	110
C7—C8—H8	123.7	C20—C19—H19B	110
C8—C9—S2	112.5 (3)	O4—C19—H19B	110
C8—C9—H9	123.8	H19A—C19—H19B	108.4
S2—C9—H9	123.8	C19—C20—H20A	109.5
N2—C10—C11	123.1 (3)	C19—C20—H20B	109.5
N2—C10—H10	118.5	H20A—C20—H20B	109.5
C11—C10—H10	118.5	C19—C20—H20C	109.5
C12—C11—C10	125.7 (3)	H20A—C20—H20C	109.5
C12—C11—S3	112.5 (3)	H20B—C20—H20C	109.5
C10—C11—S3	121.8 (3)
C5—N1—C1—C2	−163.1 (3)	C6—C7—C8—C9	−0.1 (6)
C5—N1—C1—S1	21.5 (5)	C7—C8—C9—S2	−0.1 (5)
C4—S1—C1—C2	0.8 (3)	C6—S2—C9—C8	0.2 (4)
C4—S1—C1—N1	176.7 (3)	C4—N2—C10—C11	179.5 (3)
N1—C1—C2—C3	−176.2 (3)	N2—C10—C11—C12	178.0 (4)
S1—C1—C2—C3	−0.4 (4)	N2—C10—C11—S3	−2.1 (5)
N1—C1—C2—C15	5.3 (6)	C14—S3—C11—C12	0.9 (3)
S1—C1—C2—C15	−178.9 (3)	C14—S3—C11—C10	−179.0 (3)
C1—C2—C3—C4	−0.5 (5)	C10—C11—C12—C13	179.1 (4)
C15—C2—C3—C4	178.0 (3)	S3—C11—C12—C13	−0.7 (5)
C1—C2—C3—C18	−172.8 (3)	C11—C12—C13—C14	0.1 (6)
C15—C2—C3—C18	5.7 (6)	C12—C13—C14—S3	0.5 (6)
C2—C3—C4—N2	−176.7 (3)	C11—S3—C14—C13	−0.8 (4)
C18—C3—C4—N2	−4.0 (5)	C16—O2—C15—O1	4.1 (6)
C2—C3—C4—S1	1.1 (4)	C16—O2—C15—C2	−174.0 (3)
C18—C3—C4—S1	173.8 (3)	C1—C2—C15—O1	37.9 (6)
C10—N2—C4—C3	172.4 (4)	C3—C2—C15—O1	−140.5 (4)
C10—N2—C4—S1	−5.1 (5)	C1—C2—C15—O2	−144.1 (3)
C1—S1—C4—C3	−1.1 (3)	C3—C2—C15—O2	37.6 (5)
C1—S1—C4—N2	176.7 (3)	C15—O2—C16—C17	129.7 (4)
C1—N1—C5—C6	−179.6 (3)	C19—O4—C18—O3	5.5 (6)
N1—C5—C6—C7	−173.4 (4)	C19—O4—C18—C3	−174.2 (3)
N1—C5—C6—S2	5.1 (5)	C4—C3—C18—O3	−111.2 (4)
C9—S2—C6—C7	−0.2 (3)	C2—C3—C18—O3	60.6 (5)
C9—S2—C6—C5	−178.9 (3)	C4—C3—C18—O4	68.5 (4)
C5—C6—C7—C8	178.9 (4)	C2—C3—C18—O4	−119.7 (4)
S2—C6—C7—C8	0.2 (4)	C18—O4—C19—C20	174.5 (4)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
C5—H5···S1	0.93	2.59	3.024 (3)	109
C10—H10···S1	0.93	2.58	3.038 (4)	111
C16—H16B···O1	0.97	2.28	2.689 (5)	104