organic compounds
H-benzimidazol-2-yl)-2-[2-(4-nitrophenyl)hydrazinylidene]acetate
of ethyl 2-(1aLaboratoire de Chimie Moléculaire, Faculté des Sciences Semlalia, BP 2390, Université Cadi Ayyad, 40001 Marrakech, Morocco, bLaboratoire de Chimie du Solide Appliqué, Faculté des Sciences, Avenue Ibn Battouta, BP 1014 Rabat, Morocco, and cLaboratoire de Chimie des Substances Naturelles, URAC16, Faculté des Sciences Semlalia, BP 2390 Bd My Abdellah, 40000 Marrakech, Morocco
*Correspondence e-mail: berraho@uca.ma
The title compound, C17H15N5O4, was obtained via the condensation of 3-ethoxy-2-[2-(4-nitrophenyl)hydrazono]-3-oxopropanoic acid with 1,2-diaminobenzene. In the molecule, the dihedral angles between the acetate group and the two aromatic subunits (benzimidazole and nitrophenylhydrazone) are 7.35 (9) and 18.23 (9)°, respectively. Intramolecular N—H⋯O and N—H⋯N contacts occur. In the crystal, C—H⋯O and N—H⋯O hydrogen bonds link the molecules into chains along the b-axis direction.
Keywords: crystal structure; benzimidazole; nitrophenylhydrazone; hydrogen bonding.
CCDC reference: 1052904
1. Related literature
For the pharmacological activity of benzimidazole derivatives, see: Luo et al. (2011); Ouattara et al. (2011); Bhrigu et al. (2012); Singh et al. (2012); Parajuli et al. (2014). For their agrochemical activity, see: Attrassi et al. (2007).
2. Experimental
2.1. Crystal data
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2.2. Data collection
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2.3. Refinement
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Data collection: APEX2 (Bruker, 2009); cell SAINT-Plus (Bruker, 2009); data reduction: SAINT-Plus; program(s) used to solve structure: SHELXS97 (Sheldrick,2008); program(s) used to refine structure: SHELXL97 (Sheldrick,2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012); software used to prepare material for publication: WinGX (Farrugia, 2012).
Supporting information
CCDC reference: 1052904
10.1107/S2056989015004818/im2461sup1.cif
contains datablock I. DOI:Structure factors: contains datablock I. DOI: 10.1107/S2056989015004818/im2461Isup2.hkl
Supporting information file. DOI: 10.1107/S2056989015004818/im2461Isup3.cml
1,2-diaminobenzene (0.5 g, 4.6 mmol) and 3-ethoxy-2-[2-(4-nitrophenyl)hydrazono]-3-oxopropanoic acid (1.19 g, 4.6 mmol) were heated in xylene (15 ml) for 12 h. The solvent was evaporated. The title compound was isolated by
on silica gel using hexane/ethyl acetate as The solid product was recrystallized in dichloromethane at 15°C to give yellow crystals (yield: 45%) of the title compound.All H atoms were fixed geometrically and treated as riding with C—H = 0.96 Å (methyl), 0.97 Å (methylene) and 0.98 Å (methine) with Uiso(H) = 1.2 Ueq(methylene, methine and OH) or Uiso(H) = 1.5 Ueq(methyl).
The development of an efficient synthesis of bioactive compounds is a major challenge in modern chemistry. The high therapeutic properties of benzimidazole derivatives related drugs have encouraged the medicinal chemists to synthesize a large number of new chemotherapeutic agents. The benzimidazole motif is an integral part in numerous fields, as pharmaceuticals (Luo et al., 2011; Ouattara et al., 2011; Bhrigu et al., 2012; Singh et al., 2012; Parajuli et al., 2014), and agrochemicals (Attrassi et al., 2007). The structure of this new product was determined by its single-crystal X-ray structure. The dihedral angles between the acetate chain and the two aromatic subunits (benzimidazole and nitrophenylhydrazone) are 7.35 (9)° and 18.23 (9)°, respectively. In the
the molecules are linked by C—H···O and N—H···O intermolecular hydrogen bonds into chains along the b axis (Fig.2). In addition an intramolecular N—H···O hydrogen bond is also observed.For the pharmacological activity of benzimidazole derivatives, see: Luo et al. (2011); Ouattara et al. (2011); Bhrigu et al. (2012); Singh et al. (2012); Parajuli et al. (2014). For their agrochemical activity, see: Attrassi et al. (2007).
Data collection: APEX2 (Bruker, 2009); cell
SAINT-Plus (Bruker, 2009); data reduction: SAINT-Plus (Bruker, 2009); program(s) used to solve structure: SHELXS97 (Sheldrick,2008); program(s) used to refine structure: SHELXL97 (Sheldrick,2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012); software used to prepare material for publication: WinGX (Farrugia, 2012).C17H15N5O4 | F(000) = 736 |
Mr = 353.34 | Dx = 1.429 Mg m−3 |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2ybc | Cell parameters from 3362 reflections |
a = 12.877 (5) Å | θ = 2.7–26.4° |
b = 5.874 (5) Å | µ = 0.11 mm−1 |
c = 21.988 (5) Å | T = 293 K |
β = 99.060 (5)° | Platelet, colourless |
V = 1642.4 (16) Å3 | 0.33 × 0.17 × 0.04 mm |
Z = 4 |
Bruker APEXII CCD diffractometer | 2562 reflections with I > 2σ(I) |
Radiation source: fine-focus sealed tube | Rint = 0.033 |
Graphite monochromator | θmax = 26.4°, θmin = 2.7° |
ω and φ scans | h = −16→16 |
24995 measured reflections | k = −7→7 |
3362 independent reflections | l = −27→27 |
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)] = 0.038 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.108 | H-atom parameters constrained |
S = 1.03 | w = 1/[σ2(Fo2) + (0.0471P)2 + 0.5028P] where P = (Fo2 + 2Fc2)/3 |
3362 reflections | (Δ/σ)max < 0.001 |
236 parameters | Δρmax = 0.19 e Å−3 |
0 restraints | Δρmin = −0.17 e Å−3 |
C17H15N5O4 | V = 1642.4 (16) Å3 |
Mr = 353.34 | Z = 4 |
Monoclinic, P21/c | Mo Kα radiation |
a = 12.877 (5) Å | µ = 0.11 mm−1 |
b = 5.874 (5) Å | T = 293 K |
c = 21.988 (5) Å | 0.33 × 0.17 × 0.04 mm |
β = 99.060 (5)° |
Bruker APEXII CCD diffractometer | 2562 reflections with I > 2σ(I) |
24995 measured reflections | Rint = 0.033 |
3362 independent reflections |
R[F2 > 2σ(F2)] = 0.038 | 0 restraints |
wR(F2) = 0.108 | H-atom parameters constrained |
S = 1.03 | Δρmax = 0.19 e Å−3 |
3362 reflections | Δρmin = −0.17 e Å−3 |
236 parameters |
Geometry. All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'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 > 2σ(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. |
x | y | z | Uiso*/Ueq | ||
C1 | 0.24083 (11) | 0.7913 (3) | 0.32924 (7) | 0.0367 (3) | |
C12 | 0.49273 (11) | 0.6017 (3) | 0.39833 (6) | 0.0349 (3) | |
C13 | 0.46733 (12) | 0.3904 (3) | 0.42102 (7) | 0.0405 (4) | |
H13 | 0.3980 | 0.3398 | 0.4147 | 0.049* | |
C5 | 0.25493 (11) | 0.9962 (3) | 0.29411 (7) | 0.0357 (3) | |
C15 | 0.64834 (12) | 0.3339 (3) | 0.46186 (7) | 0.0415 (4) | |
C2 | 0.13384 (12) | 0.6936 (3) | 0.32829 (7) | 0.0413 (4) | |
C17 | 0.59698 (12) | 0.6755 (3) | 0.40730 (7) | 0.0406 (4) | |
H17 | 0.6138 | 0.8155 | 0.3917 | 0.049* | |
C6 | 0.32726 (11) | 1.2789 (3) | 0.25402 (7) | 0.0365 (3) | |
C11 | 0.39466 (12) | 1.4456 (3) | 0.23679 (7) | 0.0410 (4) | |
H11 | 0.4662 | 1.4438 | 0.2521 | 0.049* | |
C16 | 0.67524 (12) | 0.5414 (3) | 0.43928 (7) | 0.0439 (4) | |
H16 | 0.7448 | 0.5900 | 0.4455 | 0.053* | |
C8 | 0.17657 (12) | 1.4543 (3) | 0.18916 (8) | 0.0460 (4) | |
H8 | 0.1052 | 1.4564 | 0.1733 | 0.055* | |
C9 | 0.24422 (13) | 1.6167 (3) | 0.17267 (8) | 0.0470 (4) | |
H9 | 0.2180 | 1.7311 | 0.1453 | 0.056* | |
C14 | 0.54567 (13) | 0.2574 (3) | 0.45284 (7) | 0.0437 (4) | |
H14 | 0.5295 | 0.1165 | 0.4682 | 0.052* | |
C10 | 0.35198 (12) | 1.6127 (3) | 0.19643 (7) | 0.0441 (4) | |
H10 | 0.3955 | 1.7253 | 0.1847 | 0.053* | |
C7 | 0.21950 (11) | 1.2872 (3) | 0.23044 (7) | 0.0378 (3) | |
C3 | 0.03236 (14) | 0.4189 (4) | 0.37222 (10) | 0.0645 (5) | |
H3A | 0.0032 | 0.3445 | 0.3339 | 0.077* | |
H3B | −0.0167 | 0.5349 | 0.3811 | 0.077* | |
N1 | 0.34778 (9) | 1.0947 (2) | 0.29374 (6) | 0.0382 (3) | |
N2 | 0.17568 (9) | 1.1066 (2) | 0.25700 (6) | 0.0401 (3) | |
H2 | 0.1102 | 1.0698 | 0.2513 | 0.048* | |
N3 | 0.31612 (9) | 0.6757 (2) | 0.36227 (6) | 0.0384 (3) | |
N4 | 0.41544 (9) | 0.7421 (2) | 0.36668 (6) | 0.0390 (3) | |
H4 | 0.4316 | 0.8680 | 0.3505 | 0.047* | |
N5 | 0.73044 (13) | 0.1896 (3) | 0.49538 (7) | 0.0567 (4) | |
O1 | 0.82217 (12) | 0.2456 (3) | 0.49629 (8) | 0.0857 (5) | |
O2 | 0.70291 (13) | 0.0185 (2) | 0.52145 (7) | 0.0771 (4) | |
O3 | 0.13339 (9) | 0.5214 (2) | 0.36682 (6) | 0.0566 (3) | |
O4 | 0.05567 (8) | 0.7645 (2) | 0.29566 (6) | 0.0548 (3) | |
C4 | 0.04983 (17) | 0.2514 (4) | 0.42261 (11) | 0.0837 (7) | |
H4A | 0.0745 | 0.3282 | 0.4607 | 0.126* | |
H4B | 0.1014 | 0.1423 | 0.4144 | 0.126* | |
H4C | −0.0150 | 0.1746 | 0.4256 | 0.126* |
U11 | U22 | U33 | U12 | U13 | U23 | |
C1 | 0.0289 (7) | 0.0419 (8) | 0.0390 (8) | 0.0026 (6) | 0.0040 (6) | −0.0048 (6) |
C12 | 0.0317 (7) | 0.0409 (8) | 0.0317 (7) | 0.0023 (6) | 0.0040 (6) | −0.0034 (6) |
C13 | 0.0342 (8) | 0.0451 (9) | 0.0424 (8) | −0.0027 (7) | 0.0063 (7) | −0.0026 (7) |
C5 | 0.0284 (7) | 0.0394 (8) | 0.0388 (8) | 0.0026 (6) | 0.0036 (6) | −0.0068 (6) |
C15 | 0.0431 (9) | 0.0444 (9) | 0.0354 (8) | 0.0112 (7) | 0.0012 (6) | −0.0017 (7) |
C2 | 0.0333 (8) | 0.0440 (8) | 0.0465 (9) | 0.0006 (7) | 0.0063 (7) | −0.0017 (7) |
C17 | 0.0349 (8) | 0.0401 (8) | 0.0462 (9) | −0.0013 (6) | 0.0042 (7) | 0.0037 (7) |
C6 | 0.0311 (7) | 0.0399 (8) | 0.0382 (8) | 0.0027 (6) | 0.0048 (6) | −0.0064 (6) |
C11 | 0.0305 (7) | 0.0482 (9) | 0.0444 (9) | −0.0024 (6) | 0.0059 (6) | −0.0075 (7) |
C16 | 0.0307 (8) | 0.0520 (10) | 0.0478 (9) | 0.0002 (7) | 0.0024 (7) | −0.0031 (8) |
C8 | 0.0317 (8) | 0.0497 (9) | 0.0546 (10) | 0.0042 (7) | 0.0009 (7) | 0.0016 (8) |
C9 | 0.0449 (9) | 0.0457 (9) | 0.0504 (9) | 0.0047 (7) | 0.0082 (7) | 0.0033 (8) |
C14 | 0.0509 (10) | 0.0395 (8) | 0.0416 (8) | 0.0002 (7) | 0.0098 (7) | 0.0019 (7) |
C10 | 0.0420 (9) | 0.0452 (9) | 0.0467 (9) | −0.0055 (7) | 0.0122 (7) | −0.0042 (7) |
C7 | 0.0297 (7) | 0.0396 (8) | 0.0439 (8) | 0.0008 (6) | 0.0052 (6) | −0.0045 (7) |
C3 | 0.0377 (9) | 0.0708 (12) | 0.0829 (14) | −0.0125 (9) | 0.0033 (9) | 0.0184 (11) |
N1 | 0.0289 (6) | 0.0420 (7) | 0.0430 (7) | 0.0009 (5) | 0.0036 (5) | −0.0044 (6) |
N2 | 0.0249 (6) | 0.0435 (7) | 0.0505 (8) | 0.0004 (5) | 0.0017 (5) | 0.0006 (6) |
N3 | 0.0297 (6) | 0.0451 (7) | 0.0402 (7) | 0.0003 (5) | 0.0046 (5) | −0.0049 (6) |
N4 | 0.0279 (6) | 0.0435 (7) | 0.0443 (7) | −0.0005 (5) | 0.0015 (5) | 0.0026 (6) |
N5 | 0.0581 (10) | 0.0579 (10) | 0.0501 (9) | 0.0171 (8) | −0.0038 (7) | −0.0030 (8) |
O1 | 0.0495 (8) | 0.0996 (12) | 0.1017 (12) | 0.0226 (8) | −0.0076 (8) | 0.0158 (10) |
O2 | 0.0933 (11) | 0.0556 (8) | 0.0748 (10) | 0.0155 (8) | −0.0109 (8) | 0.0150 (7) |
O3 | 0.0330 (6) | 0.0639 (8) | 0.0703 (8) | −0.0079 (5) | 0.0002 (5) | 0.0183 (6) |
O4 | 0.0278 (6) | 0.0640 (8) | 0.0704 (8) | 0.0009 (5) | 0.0006 (5) | 0.0136 (6) |
C4 | 0.0629 (13) | 0.0951 (17) | 0.0888 (16) | −0.0217 (12) | −0.0014 (12) | 0.0320 (14) |
C1—N3 | 1.3064 (19) | C16—H16 | 0.9300 |
C1—C5 | 1.457 (2) | C8—C9 | 1.378 (2) |
C1—C2 | 1.490 (2) | C8—C7 | 1.391 (2) |
C12—N4 | 1.3921 (19) | C8—H8 | 0.9300 |
C12—C17 | 1.395 (2) | C9—C10 | 1.404 (2) |
C12—C13 | 1.396 (2) | C9—H9 | 0.9300 |
C13—C14 | 1.377 (2) | C14—H14 | 0.9300 |
C13—H13 | 0.9300 | C10—H10 | 0.9300 |
C5—N1 | 1.3295 (19) | C7—N2 | 1.374 (2) |
C5—N2 | 1.3659 (19) | C3—O3 | 1.455 (2) |
C15—C16 | 1.381 (2) | C3—C4 | 1.472 (3) |
C15—C14 | 1.381 (2) | C3—H3A | 0.9700 |
C15—N5 | 1.461 (2) | C3—H3B | 0.9700 |
C2—O4 | 1.2140 (18) | N2—H2 | 0.8600 |
C2—O3 | 1.320 (2) | N3—N4 | 1.3259 (17) |
C17—C16 | 1.381 (2) | N4—H4 | 0.8600 |
C17—H17 | 0.9300 | N5—O1 | 1.223 (2) |
C6—N1 | 1.389 (2) | N5—O2 | 1.236 (2) |
C6—C11 | 1.400 (2) | C4—H4A | 0.9600 |
C6—C7 | 1.404 (2) | C4—H4B | 0.9600 |
C11—C10 | 1.378 (2) | C4—H4C | 0.9600 |
C11—H11 | 0.9300 | ||
N3—C1—C5 | 125.50 (13) | C10—C9—H9 | 119.4 |
N3—C1—C2 | 114.28 (14) | C13—C14—C15 | 119.79 (15) |
C5—C1—C2 | 120.20 (13) | C13—C14—H14 | 120.1 |
N4—C12—C17 | 118.87 (14) | C15—C14—H14 | 120.1 |
N4—C12—C13 | 121.10 (13) | C11—C10—C9 | 121.48 (15) |
C17—C12—C13 | 120.03 (14) | C11—C10—H10 | 119.3 |
C14—C13—C12 | 119.47 (15) | C9—C10—H10 | 119.3 |
C14—C13—H13 | 120.3 | N2—C7—C8 | 132.42 (14) |
C12—C13—H13 | 120.3 | N2—C7—C6 | 105.33 (13) |
N1—C5—N2 | 112.18 (14) | C8—C7—C6 | 122.25 (14) |
N1—C5—C1 | 123.37 (13) | O3—C3—C4 | 107.77 (15) |
N2—C5—C1 | 124.43 (13) | O3—C3—H3A | 110.2 |
C16—C15—C14 | 121.63 (14) | C4—C3—H3A | 110.2 |
C16—C15—N5 | 119.41 (15) | O3—C3—H3B | 110.2 |
C14—C15—N5 | 118.96 (16) | C4—C3—H3B | 110.2 |
O4—C2—O3 | 123.72 (14) | H3A—C3—H3B | 108.5 |
O4—C2—C1 | 123.71 (15) | C5—N1—C6 | 105.10 (12) |
O3—C2—C1 | 112.57 (13) | C5—N2—C7 | 107.60 (12) |
C16—C17—C12 | 120.24 (15) | C5—N2—H2 | 126.2 |
C16—C17—H17 | 119.9 | C7—N2—H2 | 126.2 |
C12—C17—H17 | 119.9 | C1—N3—N4 | 120.69 (14) |
N1—C6—C11 | 130.57 (14) | N3—N4—C12 | 117.87 (13) |
N1—C6—C7 | 109.78 (13) | N3—N4—H4 | 121.1 |
C11—C6—C7 | 119.65 (14) | C12—N4—H4 | 121.1 |
C10—C11—C6 | 118.11 (14) | O1—N5—O2 | 123.90 (16) |
C10—C11—H11 | 120.9 | O1—N5—C15 | 118.19 (17) |
C6—C11—H11 | 120.9 | O2—N5—C15 | 117.91 (17) |
C15—C16—C17 | 118.83 (15) | C2—O3—C3 | 117.63 (13) |
C15—C16—H16 | 120.6 | C3—C4—H4A | 109.5 |
C17—C16—H16 | 120.6 | C3—C4—H4B | 109.5 |
C9—C8—C7 | 117.22 (15) | H4A—C4—H4B | 109.5 |
C9—C8—H8 | 121.4 | C3—C4—H4C | 109.5 |
C7—C8—H8 | 121.4 | H4A—C4—H4C | 109.5 |
C8—C9—C10 | 121.29 (16) | H4B—C4—H4C | 109.5 |
C8—C9—H9 | 119.4 |
D—H···A | D—H | H···A | D···A | D—H···A |
N2—H2···O4i | 0.86 | 2.50 | 3.161 (3) | 134 |
C8—H8···O4i | 0.93 | 2.54 | 3.258 (3) | 134 |
N2—H2···O4 | 0.86 | 2.21 | 2.750 (3) | 121 |
N4—H4···N1 | 0.86 | 2.02 | 2.679 (3) | 133 |
Symmetry code: (i) −x, y+1/2, −z+1/2. |
D—H···A | D—H | H···A | D···A | D—H···A |
N2—H2···O4i | 0.86 | 2.50 | 3.161 (3) | 134 |
C8—H8···O4i | 0.93 | 2.54 | 3.258 (3) | 134 |
N2—H2···O4 | 0.86 | 2.21 | 2.750 (3) | 121 |
N4—H4···N1 | 0.86 | 2.02 | 2.679 (3) | 133 |
Symmetry code: (i) −x, y+1/2, −z+1/2. |
Acknowledgements
The authors thank the Unit of Support for Technical and Scientific Research (UATRS, CNRST) for the X-ray measurements.
References
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The development of an efficient synthesis of bioactive compounds is a major challenge in modern chemistry. The high therapeutic properties of benzimidazole derivatives related drugs have encouraged the medicinal chemists to synthesize a large number of new chemotherapeutic agents. The benzimidazole motif is an integral part in numerous fields, as pharmaceuticals (Luo et al., 2011; Ouattara et al., 2011; Bhrigu et al., 2012; Singh et al., 2012; Parajuli et al., 2014), and agrochemicals (Attrassi et al., 2007). The structure of this new product was determined by its single-crystal X-ray structure. The dihedral angles between the acetate chain and the two aromatic subunits (benzimidazole and nitrophenylhydrazone) are 7.35 (9)° and 18.23 (9)°, respectively. In the crystal structure, the molecules are linked by C—H···O and N—H···O intermolecular hydrogen bonds into chains along the b axis (Fig.2). In addition an intramolecular N—H···O hydrogen bond is also observed.