

Supporting information
![]() | Crystallographic Information File (CIF) https://doi.org/10.1107/S1600536814003651/is5340sup1.cif |
![]() | Structure factor file (CIF format) https://doi.org/10.1107/S1600536814003651/is5340Isup2.hkl |
![]() | Chemical Markup Language (CML) file https://doi.org/10.1107/S1600536814003651/is5340Isup3.cml |
CCDC reference: 987496
Key indicators
- Single-crystal X-ray study
- T = 298 K
- Mean
(C-C) = 0.007 Å
- R factor = 0.036
- wR factor = 0.072
- Data-to-parameter ratio = 17.0
checkCIF/PLATON results
No syntax errors found
Alert level C PLAT090_ALERT_3_C Poor Data / Parameter Ratio (Zmax > 18) ........ 9.62 Note PLAT242_ALERT_2_C Low Ueq as Compared to Neighbors for ..... C4 Check PLAT341_ALERT_3_C Low Bond Precision on C-C Bonds ............... 0.0070 Ang.
Alert level G PLAT005_ALERT_5_G No _iucr_refine_instructions_details in the CIF Please Do ! PLAT791_ALERT_4_G The Model has Chirality at C7 ............. S Verify PLAT910_ALERT_3_G Missing # of FCF Reflections Below Th(Min) ..... 2 Why ?
0 ALERT level A = Most likely a serious problem - resolve or explain 0 ALERT level B = A potentially serious problem, consider carefully 3 ALERT level C = Check. Ensure it is not caused by an omission or oversight 3 ALERT level G = General information/check it is not something unexpected 0 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 3 ALERT type 3 Indicator that the structure quality may be low 1 ALERT type 4 Improvement, methodology, query or suggestion 1 ALERT type 5 Informative message, check
Under solvent-free conditions, a mixture of 2,5-thiophenedicarboxaldehyde (100 mg, 0.71 mmol) and (S)-(–)-1-(4-bromophenyl)ethylamine (285 mg, 1.42 mmol) in a 1:2 molar ratio were mixed at room temperature, giving a white solid. The crude was recrystallized from CH2Cl2, affording colorless crystals of the title compound.
Yield 96%; m.p. 147–149 °C. Spectroscopic data: [a]D25 = +59.6 (c 1, CHCl3). IR (KBr): 1623 cm-1 (C=N). 1H NMR (400 MHz, CDCl3/TMS): δ = 1.51, 1.53 (d, 6H, CHCH3,), 4.44, 4.45, 4.47, 4.49(q, 2H, CH), 7.29–7.45 (m, 10 H, Ar), 8.36 (s, 2 H, HC=N). 13C NMR (100 MHz, CDCl3/TMS) δ = 25.1 (CCH3), 68.7 (CHCH3), 120.6 (Ar), 128.3 (Ar), 130.1 (Ar), 131.4 (Ar), 144.0 (Ar), 145.1 (Ar), 152. 7 (HC=N). MS—EI: m/z= 504 (M+).
The absolute configuration was determined using the anomalous dispersion of the Br atom, and was that expected from the synthesis, carried-out with an enantiomerically pure amine. All H atoms were placed in calculated positions, with C—H bond lengths fixed to 0.96 Å for the methyl group and 0.93 Å for aromatic CH groups. Isotropic displacement parameters were calculated as Uiso(H) = 1.5Ueq(carrier atom) for the methyl group and Uiso(H) = 1.2Ueq(carrier atom) otherwise.
Data collection: CrysAlis PRO (Agilent, 2013); cell refinement: CrysAlis PRO (Agilent, 2013); data reduction: CrysAlis RED (Agilent, 2013); program(s) used to solve structure: SHELXS2013 (Sheldrick, 2008); program(s) used to refine structure: SHELXL2013 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012); software used to prepare material for publication: WinGX (Farrugia, 2012).
C22H20Br2N2S | F(000) = 504 |
Mr = 504.27 | Dx = 1.521 Mg m−3 |
Monoclinic, C2 | Melting point: 420 K |
Hall symbol: C 2y | Mo Kα radiation, λ = 0.71073 Å |
a = 24.5329 (15) Å | Cell parameters from 1609 reflections |
b = 5.9762 (5) Å | θ = 4.4–25.2° |
c = 7.5944 (5) Å | µ = 3.79 mm−1 |
β = 98.536 (6)° | T = 298 K |
V = 1101.11 (14) Å3 | Prism, colourless |
Z = 2 | 0.52 × 0.15 × 0.06 mm |
Agilent Xcalibur (Atlas, Gemini) diffractometer | 2107 independent reflections |
Radiation source: Enhance (Mo) X-ray Source | 1630 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.035 |
Detector resolution: 10.5564 pixels mm-1 | θmax = 26.1°, θmin = 3.0° |
ω scans | h = −30→30 |
Absorption correction: numerical (CrysAlis PRO; Agilent, 2013) | k = −7→7 |
Tmin = 0.400, Tmax = 0.815 | l = −9→9 |
6101 measured reflections |
Refinement on F2 | Hydrogen site location: inferred from neighbouring sites |
Least-squares matrix: full | H-atom parameters constrained |
R[F2 > 2σ(F2)] = 0.036 | w = 1/[σ2(Fo2) + (0.0288P)2 + 0.0296P]
where P = (Fo2 + 2Fc2)/3 |
wR(F2) = 0.072 | (Δ/σ)max < 0.001 |
S = 1.03 | Δρmax = 0.20 e Å−3 |
2107 reflections | Δρmin = −0.35 e Å−3 |
124 parameters | Absolute structure: Flack (1983), 914 Friedel pairs |
1 restraint | Absolute structure parameter: 0.011 (8) |
0 constraints |
C22H20Br2N2S | V = 1101.11 (14) Å3 |
Mr = 504.27 | Z = 2 |
Monoclinic, C2 | Mo Kα radiation |
a = 24.5329 (15) Å | µ = 3.79 mm−1 |
b = 5.9762 (5) Å | T = 298 K |
c = 7.5944 (5) Å | 0.52 × 0.15 × 0.06 mm |
β = 98.536 (6)° |
Agilent Xcalibur (Atlas, Gemini) diffractometer | 2107 independent reflections |
Absorption correction: numerical (CrysAlis PRO; Agilent, 2013) | 1630 reflections with I > 2σ(I) |
Tmin = 0.400, Tmax = 0.815 | Rint = 0.035 |
6101 measured reflections |
R[F2 > 2σ(F2)] = 0.036 | H-atom parameters constrained |
wR(F2) = 0.072 | Δρmax = 0.20 e Å−3 |
S = 1.03 | Δρmin = −0.35 e Å−3 |
2107 reflections | Absolute structure: Flack (1983), 914 Friedel pairs |
124 parameters | Absolute structure parameter: 0.011 (8) |
1 restraint |
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. |
x | y | z | Uiso*/Ueq | ||
Br1 | 0.15628 (2) | 0.49000 (18) | 0.61658 (7) | 0.1112 (4) | |
S1 | 0.5 | 0.2196 (2) | 0.5 | 0.0472 (4) | |
C9 | 0.47486 (16) | 0.0181 (7) | 0.6292 (5) | 0.0427 (10) | |
C11 | 0.4216 (2) | 0.4840 (10) | 1.0744 (5) | 0.0657 (13) | |
H11A | 0.4194 | 0.6248 | 1.0129 | 0.099* | |
H11B | 0.4595 | 0.4499 | 1.1175 | 0.099* | |
H11C | 0.4013 | 0.4929 | 1.173 | 0.099* | |
C4 | 0.2306 (2) | 0.4327 (11) | 0.7169 (6) | 0.0639 (15) | |
C1 | 0.33894 (18) | 0.3489 (7) | 0.8651 (5) | 0.0441 (11) | |
C6 | 0.3243 (2) | 0.5418 (9) | 0.7670 (6) | 0.0569 (13) | |
H6 | 0.3514 | 0.6457 | 0.7513 | 0.068* | |
N1 | 0.43094 (15) | 0.2748 (6) | 0.8052 (5) | 0.0452 (9) | |
C5 | 0.2703 (2) | 0.5823 (9) | 0.6921 (7) | 0.0674 (16) | |
H5 | 0.2613 | 0.711 | 0.6253 | 0.081* | |
C2 | 0.2971 (2) | 0.1997 (9) | 0.8837 (6) | 0.0603 (13) | |
H2 | 0.3056 | 0.0688 | 0.9482 | 0.072* | |
C3 | 0.2431 (2) | 0.2389 (11) | 0.8092 (7) | 0.0690 (14) | |
H3 | 0.2157 | 0.135 | 0.8218 | 0.083* | |
C7 | 0.3974 (2) | 0.3024 (8) | 0.9485 (5) | 0.0501 (12) | |
H7 | 0.398 | 0.1616 | 1.0149 | 0.06* | |
C8 | 0.44434 (18) | 0.0769 (7) | 0.7709 (6) | 0.0469 (12) | |
H8 | 0.4339 | −0.038 | 0.8414 | 0.056* | |
C10 | 0.4853 (2) | −0.1907 (8) | 0.5728 (7) | 0.0540 (13) | |
H10 | 0.4743 | −0.3205 | 0.625 | 0.065* |
U11 | U22 | U33 | U12 | U13 | U23 | |
Br1 | 0.0529 (4) | 0.2036 (8) | 0.0729 (4) | 0.0279 (5) | −0.0044 (3) | −0.0229 (5) |
S1 | 0.0553 (11) | 0.0347 (8) | 0.0547 (10) | 0 | 0.0179 (8) | 0 |
C9 | 0.043 (2) | 0.038 (2) | 0.047 (2) | 0.001 (2) | 0.0052 (18) | 0.005 (2) |
C11 | 0.058 (3) | 0.085 (3) | 0.053 (2) | 0.009 (3) | 0.005 (2) | −0.003 (3) |
C4 | 0.044 (3) | 0.106 (5) | 0.042 (2) | 0.005 (3) | 0.006 (2) | −0.009 (3) |
C1 | 0.044 (3) | 0.053 (3) | 0.037 (2) | 0.001 (2) | 0.012 (2) | 0.002 (2) |
C6 | 0.052 (3) | 0.062 (3) | 0.056 (3) | −0.002 (3) | 0.007 (2) | 0.016 (3) |
N1 | 0.042 (2) | 0.052 (2) | 0.0439 (19) | 0.0014 (17) | 0.0134 (17) | 0.0053 (16) |
C5 | 0.063 (4) | 0.084 (4) | 0.053 (3) | 0.010 (3) | 0.003 (3) | 0.014 (3) |
C2 | 0.064 (4) | 0.067 (3) | 0.053 (3) | −0.002 (3) | 0.017 (2) | 0.011 (3) |
C3 | 0.051 (3) | 0.094 (4) | 0.065 (3) | −0.019 (3) | 0.017 (3) | −0.005 (3) |
C7 | 0.051 (3) | 0.060 (3) | 0.043 (2) | 0.006 (2) | 0.017 (2) | 0.011 (2) |
C8 | 0.039 (3) | 0.051 (3) | 0.051 (3) | 0.000 (2) | 0.008 (2) | 0.013 (2) |
C10 | 0.057 (3) | 0.035 (2) | 0.073 (3) | −0.001 (2) | 0.017 (3) | 0.005 (2) |
Br1—C4 | 1.899 (5) | C1—C7 | 1.505 (6) |
S1—C9i | 1.724 (4) | C6—H6 | 0.93 |
S1—C9 | 1.724 (4) | C6—C5 | 1.383 (7) |
C9—C8 | 1.442 (6) | N1—C7 | 1.468 (5) |
C9—C10 | 1.356 (6) | N1—C8 | 1.265 (5) |
C11—H11A | 0.96 | C5—H5 | 0.93 |
C11—H11B | 0.96 | C2—H2 | 0.93 |
C11—H11C | 0.96 | C2—C3 | 1.382 (7) |
C11—C7 | 1.509 (7) | C3—H3 | 0.93 |
C4—C5 | 1.356 (7) | C7—H7 | 0.98 |
C4—C3 | 1.365 (7) | C8—H8 | 0.93 |
C1—C6 | 1.391 (6) | C10—C10i | 1.405 (10) |
C1—C2 | 1.383 (7) | C10—H10 | 0.93 |
C9—S1—C9i | 91.4 (3) | C4—C5—H5 | 120.3 |
C8—C9—S1 | 121.6 (3) | C6—C5—H5 | 120.3 |
C10—C9—S1 | 111.2 (3) | C1—C2—H2 | 119 |
C10—C9—C8 | 127.1 (4) | C3—C2—C1 | 122.0 (5) |
H11A—C11—H11B | 109.5 | C3—C2—H2 | 119 |
H11A—C11—H11C | 109.5 | C4—C3—C2 | 118.9 (5) |
H11B—C11—H11C | 109.5 | C4—C3—H3 | 120.6 |
C7—C11—H11A | 109.5 | C2—C3—H3 | 120.6 |
C7—C11—H11B | 109.5 | C11—C7—H7 | 108.5 |
C7—C11—H11C | 109.5 | C1—C7—C11 | 113.2 (4) |
C5—C4—Br1 | 119.5 (4) | C1—C7—H7 | 108.5 |
C5—C4—C3 | 121.3 (5) | N1—C7—C11 | 109.9 (4) |
C3—C4—Br1 | 119.2 (4) | N1—C7—C1 | 108.2 (3) |
C6—C1—C7 | 122.2 (4) | N1—C7—H7 | 108.5 |
C2—C1—C6 | 116.9 (4) | C9—C8—H8 | 117.9 |
C2—C1—C7 | 120.9 (4) | N1—C8—C9 | 124.1 (4) |
C1—C6—H6 | 119.3 | N1—C8—H8 | 117.9 |
C5—C6—C1 | 121.3 (5) | C9—C10—C10i | 113.1 (3) |
C5—C6—H6 | 119.3 | C9—C10—H10 | 123.5 |
C8—N1—C7 | 116.7 (3) | C10i—C10—H10 | 123.5 |
C4—C5—C6 | 119.5 (5) | ||
Br1—C4—C5—C6 | 179.2 (4) | C2—C1—C6—C5 | 0.2 (7) |
Br1—C4—C3—C2 | −179.2 (4) | C2—C1—C7—C11 | −122.6 (5) |
S1—C9—C8—N1 | 4.2 (6) | C2—C1—C7—N1 | 115.3 (4) |
S1—C9—C10—C10i | 1.2 (7) | C3—C4—C5—C6 | −2.3 (8) |
C9i—S1—C9—C8 | −177.3 (4) | C7—C1—C6—C5 | −179.6 (4) |
C9i—S1—C9—C10 | −0.4 (3) | C7—C1—C2—C3 | 179.7 (4) |
C1—C6—C5—C4 | 1.0 (7) | C7—N1—C8—C9 | 176.9 (4) |
C1—C2—C3—C4 | −1.0 (7) | C8—C9—C10—C10i | 177.9 (5) |
C6—C1—C2—C3 | −0.2 (7) | C8—N1—C7—C11 | 131.9 (4) |
C6—C1—C7—C11 | 57.3 (5) | C8—N1—C7—C1 | −104.0 (4) |
C6—C1—C7—N1 | −64.8 (5) | C10—C9—C8—N1 | −172.2 (5) |
C5—C4—C3—C2 | 2.3 (7) |
Symmetry code: (i) −x+1, y, −z+1. |
Experimental details
Crystal data | |
Chemical formula | C22H20Br2N2S |
Mr | 504.27 |
Crystal system, space group | Monoclinic, C2 |
Temperature (K) | 298 |
a, b, c (Å) | 24.5329 (15), 5.9762 (5), 7.5944 (5) |
β (°) | 98.536 (6) |
V (Å3) | 1101.11 (14) |
Z | 2 |
Radiation type | Mo Kα |
µ (mm−1) | 3.79 |
Crystal size (mm) | 0.52 × 0.15 × 0.06 |
Data collection | |
Diffractometer | Agilent Xcalibur (Atlas, Gemini) diffractometer |
Absorption correction | Numerical (CrysAlis PRO; Agilent, 2013) |
Tmin, Tmax | 0.400, 0.815 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 6101, 2107, 1630 |
Rint | 0.035 |
(sin θ/λ)max (Å−1) | 0.618 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.036, 0.072, 1.03 |
No. of reflections | 2107 |
No. of parameters | 124 |
No. of restraints | 1 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.20, −0.35 |
Absolute structure | Flack (1983), 914 Friedel pairs |
Absolute structure parameter | 0.011 (8) |
Computer programs: CrysAlis PRO (Agilent, 2013), CrysAlis RED (Agilent, 2013), SHELXS2013 (Sheldrick, 2008), SHELXL2013 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 2012), WinGX (Farrugia, 2012).
In continuation of our work focused on chiral bisimines (Espinosa Leija et al., 2009; Bernès et al., 2013), we have now synthesized the title compound under the solvent-free approach because of the cleaner, safer, and easier aspects to perform in the synthetic work. So, solvent-free conditions are becoming more popular and it is often claimed that the best solvent is no solvent. (Tanaka & Toda, 2000).
The bis-aldimine compound shows an E configuration over every imine bond (Fig. 1). The molecule is an (S,S) diastereoisomer as expected by synthetic procedure. The asymmetric unit contains a half-molecule. The S atom of the molecule is located on a twofold rotation axis of the space group C2. and as a consequence the Br-aldimines groups are placed opposite to the central thiophene ring. Only some previous reports of 2,5-thiophene compounds with achiral or chiral substituents have showed C2 crystallographic symmetry like title compound (Kudyakova et al., 2012, space group C2/c; Bernès et al., 2013, space group P22121). The crystal packing does not feature any particular interactions (intra or intermolecular) and the supramolecular arrangement in the solid state shows a chevron-like pattern viewed along the b axis (Fig. 2).