research communications\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

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ISSN: 2056-9890

Crystal structure and Hirshfeld surface analysis of (E)-4-amino-N′-[1-(4-methyl­phen­yl)ethyl­­idene]benzohydrazide

aDepartment of Chemistry, Government Arts College (Autonomous), Thanthonimalai, Karur 639 005, Tamil Nadu, India
*Correspondence e-mail: manavaibala@gmail.com

Edited by G. Smith, Queensland University of Technology, Australia (Received 27 May 2017; accepted 8 June 2017; online 13 June 2017)

The structure of the title Schiff base, C16H17N3O, displays a trans configuration with respect to the C=N double bond, with a dihedral angle of 14.98 (9)° between the benzene rings. In the crystal, mol­ecules are linked by N—H⋯O and C—H⋯O hydrogen-bonding inter­actions, giving sheets extending across the (001) plane. Hirshfeld surface analysis gave fingerprint plots showing enrichment ratios for H⋯H, O⋯H, N⋯H and C⋯H contacts compared to C⋯C, N⋯N and C⋯N contacts, indicating a high propensity for H⋯H interactions to form in the crystal.

1. Chemical context

Schiff bases are an important class of compounds in the medicinal and pharmaceutical fields and have played a role in the development of coordination chemistry as they readily form stable complexes with most transition metals. These complexes show inter­esting properties, e.g. their ability to reversibly bind oxygen, catalytic activity in the hydrogenation of olefins and transfer of an amino group, photochromic properties, and complexation ability towards toxic metals (Karthikeyan et al., 2006[Karthikeyan, M. S., Prasad, D. J., Poojary, B., Subrahmanya Bhat, K., Holla, B. S. & Kumari, N. S. (2006). Bioorg. Med. Chem. 14, 7482-7489.]; Khattab et al., 2005[Khattab, S. N. (2005). Molecules, 10, 1218-1228.]; Küçükgüzel et al., 2006[Küçükgüzel, G., Kocatepe, A., De Clercq, E., Şahin, F. & Güllüce, M. (2006). Eur. J. Med. Chem. 41, 353-359.]). Hydrazone Schiff base compounds (Cao et al., 2009[Cao, G.-B. (2009). Acta Cryst. E65, o2415.]; Zhou & Yang, 2010[Zhou, C.-S. & Yang, T. (2010). Acta Cryst. E66, o365.]; Zhang et al., 2009[Zhang, M.-J., Yin, L.-Z., Wang, D.-C., Deng, X.-M. & Liu, J.-B. (2009). Acta Cryst. E65, o508.]), derived from the reaction of aldehydes with hydrazines have been shown to possess excellent biological activities, such as anti-bacterial, anti-convulsant and anti-tubercular (Bernhardt et al., 2005[Bernhardt, P. V., Chin, P., Sharpe, P. C., Wang, J. C. & Richardson, D. R. (2005). J. Biol. Inorg. Chem. 10, 761-777.]; Armstrong et al., 2003[Armstrong, C. M., Bernhardt, P. V., Chin, P. & Richardson, D. R. (2003). Eur. J. Inorg. Chem. pp. 1145-1156.]). As part of our studies in this area, the title Schiff base compound (E)-4-amino-N′-(1-(p-tol­yl)ethyl­idene)benzo­hydrazide, was prepared and the crystal structure is reported herein. Hirshfeld surface analysis was also performed for visualizing and qu­anti­fying inter­molecular inter­actions in the crystal packing of the compound.

[Scheme 1]

2. Structural commentary

The asymmetric unit of the title compound contains one independent mol­ecule (Fig. 1[link]), displaying a trans conformation with respect to its C=N double bond. The dihedral angle between the benzene rings is 14.98 (9)°. All the bond lengths are within normal ranges. The C8=N2 and C7=O1 bond lengths [1.281 (2) and 1.231 (2) Å, respectively] confirm their double-bond character, whereas the C3—N3, C7—N1 and N1—N2 values [1.365 (3), 1.357 (2) and 1.388 (2) Å, respectively]; these C—N bonds are much shorter than (nominal) isolated C—N bonds (1.46 Å) due to conjugation.

[Figure 1]
Figure 1
The mol­ecular structure of the title compound, with displacement ellipsoids drawn at the 50% probability level.

3. Supra­molecular features

In the crystal, two types of inter­molecular hydrogen-bonding inter­actions are present (Table 1[link]). The N3—H1N3⋯O1i hydrogen bond between the amino group and a symmetry-related carbonyl group generates zigzag chains extending along the b-axis direction, as shown in Fig. 2[link]. The secondary weak methyl C9—H9A⋯O1ii hydrogen-bonding inter­actions extend the structure across a (Fig. 3[link]), generating a layer lying parallel to (001). No reasonable acceptors could be identified for either the second amine N3 H atom or the hydrazide N1 H atom.

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N3—H1N3⋯O1i 0.86 2.10 2.914 (2) 159
C9—H9A⋯O1ii 0.96 2.60 3.475 (3) 152
Symmetry codes: (i) [-x, y+{\script{1\over 2}}, -z+{\script{3\over 2}}]; (ii) x+1, y, z.
[Figure 2]
Figure 2
Crystal packing of the title compound in the unit cell, showing mol­ecules linked across b via N—H⋯O hydrogen bonds (dashed lines).
[Figure 3]
Figure 3
The crystal packing in the title compound in which mol­ecules are linked across a via weak C—H⋯O hydrogen bonds (dashed lines). H atoms not involved in hydrogen-bonding inter­actions have been omitted.

4. Hirshfeld surface analysis

Hirshfeld surfaces and their associated two-dimensional fingerprint plots (Soman et al., 2014[Soman, R., Sujatha, S., De, S., Rojisha, V. C., Parameswaran, P., Varghese, B. & Arunkumar, C. (2014). Eur. J. Inorg. Chem. pp. 2653-2662.]) have been used to qu­antify the various inter­molecular inter­actions in the title compound. The Hirshfeld surface of a mol­ecule is mapped using the descriptor dnorm which encompasses two factors: one is de, representing the distance of any surface point nearest to the inter­nal atoms, and the other one is di, representing the distance of the surface point nearest to the exterior atoms and also with the van der Waals radii of the atoms (Dalal et al., 2015[Dalal, J., Sinha, N., Yadav, H. & Kumar, B. (2015). RSC Adv. 5, 57735-57748.]). The Hirshfeld surfaces mapped over dnorm (range of −0.502–1.427 Å) are displayed in Fig. 4[link]. The surfaces are shown as transparent to allow visualization of the mol­ecule. The dominant inter­action between oxygen (O) and hydrogen (H) atoms can be observed in the Hirshfeld surface as the red areas (Fig. 4[link]). Other visible spots in the Hirshfeld surfaces correspond to C—H and H—H contacts.

[Figure 4]
Figure 4
Hirshfeld surfaces mapped over dnorm for the title compound.

The inter­molecular inter­actions of the title compound are shown in the 2D fingerprint plots shown in Fig. 5[link]. H⋯H (46.1%) contacts make the largest contribution to the Hirshfeld surfaces. O⋯H/H⋯O (10.5%), inter­actions are represented by left-side blue spikes, top and bottom. The pale yellow N⋯H/H⋯N (8.8%) inter­actions are near the C⋯H regions while the green C⋯H/H⋯C inter­actions (34.2%) are between the N—H and O—H regions. The whole fingerprint region and all other inter­actions, which are a combination of de and di, are displayed in Fig. 6[link].

[Figure 5]
Figure 5
Two-dimensional fingerprint plots of the title compound.
[Figure 6]
Figure 6
Two-dimensional fingerprint plots with a dnorm view of the C⋯H/H⋯C (34.2%), H⋯H (46.1%), N⋯H/H⋯N (8.8%) and O⋯H/H⋯O (10.5%) contacts in the title compound.

5. Synthesis and crystallization

The title compound was synthesized by the reaction of a 1:1 molar ratio mixture of a hot methano­lic solution (20 mL) of 4-amini­benzoic­hydrazide (0.151 mg, Aldrich) and a hot methano­lic solution of 4-methyl­aceto­phenone (0.134 mg, Aldrich), which was refluxed for 8 h. The solution was then cooled and kept at room temperature after which colourless block-shaped crystals suitable for the X-ray analysis were obtained in a few days.

6. Refinement

Crystal data, data collection and structure refinement details are summarized in Table 2[link]. Hydrogen atoms were positioned geometrically (N—H = 0.86 Å, and C—H = 0.93 or 0.96 Å) and were refined using a riding model, with Uiso(H) = 1.2 Ueq(N, C) or 1.5Ueq(methyl C). One reflection (011) was considered to be affected by the beamstop.

Table 2
Experimental details

Crystal data
Chemical formula C16H17N3O
Mr 267.33
Crystal system, space group Orthorhombic, P212121
Temperature (K) 296
a, b, c (Å) 5.7011 (4), 15.4836 (10), 16.2128 (10)
V3) 1431.16 (16)
Z 4
Radiation type Mo Kα
μ (mm−1) 0.08
Crystal size (mm) 0.30 × 0.20 × 0.20
 
Data collection
Diffractometer Bruker Kappa APEXII CCD
Absorption correction Multi-scan (SADABS; Bruker, 2004[Bruker (2004). SAINT, APEX2, XPREP and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.])
Tmin, Tmax 0.976, 0.984
No. of measured, independent and observed [I > 2σ(I)] reflections 17427, 3501, 2784
Rint 0.027
(sin θ/λ)max−1) 0.666
 
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.045, 0.141, 1.05
No. of reflections 3501
No. of parameters 182
H-atom treatment H-atom parameters constrained
Δρmax, Δρmin (e Å−3) 0.17, −0.20
Absolute structure Flack (1983[Flack, H. D. (1983). Acta Cryst. A39, 876-881.]), 1489 Friedel pairs
Absolute structure parameter 0.6 (19)
Computer programs: APEX2 (Bruker, 2004[Bruker (2004). SAINT, APEX2, XPREP and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]), APEX2, SAINT and XPREP (Bruker, 2004[Bruker (2004). SAINT, APEX2, XPREP and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]), SIR92 (Altomare et al., 1993[Altomare, A., Cascarano, G., Giacovazzo, C. & Guagliardi, A. (1993). J. Appl. Cryst. 26, 343-350.]), SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]), ORTEP-3 for Windows (Farrugia, 2012[Farrugia, L. J. (2012). J. Appl. Cryst. 45, 849-854.]) and Mercury (Macrae et al., 2008[Macrae, C. F., Bruno, I. J., Chisholm, J. A., Edgington, P. R., McCabe, P., Pidcock, E., Rodriguez-Monge, L., Taylor, R., van de Streek, J. & Wood, P. A. (2008). J. Appl. Cryst. 41, 466-470.]).

Supporting information


Computing details top

Data collection: APEX2 (Bruker, 2004); cell refinement: APEX2 and SAINT (Bruker, 2004); data reduction: SAINT and XPREP (Bruker, 2004); program(s) used to solve structure: SIR92 (Altomare et al., 1993); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012) and Mercury (Macrae et al., 2008); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

(E)-4-Amino-N'-[1-(4-methylphenyl)ethylidene]benzohydrazide top
Crystal data top
C16H17N3OF(000) = 568
Mr = 267.33Dx = 1.241 Mg m3
Orthorhombic, P212121Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ac 2abCell parameters from 6816 reflections
a = 5.7011 (4) Åθ = 5.0–49.0°
b = 15.4836 (10) ŵ = 0.08 mm1
c = 16.2128 (10) ÅT = 296 K
V = 1431.16 (16) Å3Block, colorless
Z = 40.30 × 0.20 × 0.20 mm
Data collection top
Bruker Kappa APEXII CCD
diffractometer
3501 independent reflections
Radiation source: fine-focus sealed tube2784 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.027
ω and φ scanθmax = 28.3°, θmin = 1.8°
Absorption correction: multi-scan
(SADABS; Bruker, 2004)
h = 77
Tmin = 0.976, Tmax = 0.984k = 1720
17427 measured reflectionsl = 2121
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.045H-atom parameters constrained
wR(F2) = 0.141 w = 1/[σ2(Fo2) + (0.0847P)2 + 0.1161P]
where P = (Fo2 + 2Fc2)/3
S = 1.05(Δ/σ)max < 0.001
3501 reflectionsΔρmax = 0.17 e Å3
182 parametersΔρmin = 0.20 e Å3
0 restraintsAbsolute structure: Flack (1983), 1489 Friedel pairs
Primary atom site location: structure-invariant direct methodsAbsolute structure parameter: 0.6 (19)
Special details top

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds 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 > 2sigma(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 (Å2) top
xyzUiso*/Ueq
N10.2405 (3)0.16299 (10)0.88410 (10)0.0543 (4)
H1N0.38480.17890.88710.065*
N20.1715 (3)0.08479 (10)0.91817 (10)0.0519 (4)
C110.0364 (4)0.07382 (12)0.98126 (12)0.0518 (5)
H110.05090.05040.93830.062*
O10.1236 (3)0.19158 (9)0.83572 (11)0.0718 (5)
C50.0187 (3)0.35074 (11)0.77149 (11)0.0477 (4)
H50.12500.32830.75480.057*
C80.3188 (3)0.04879 (11)0.96690 (11)0.0450 (4)
C100.2444 (3)0.03365 (11)1.00549 (10)0.0434 (4)
C120.0420 (4)0.14777 (12)1.02002 (12)0.0557 (5)
H120.18140.17301.00260.067*
N30.3577 (4)0.55025 (11)0.74979 (15)0.0824 (6)
H2N30.49050.57090.76540.099*
H1N30.26500.58110.72010.099*
C30.2940 (4)0.46854 (11)0.77215 (12)0.0514 (4)
C40.0803 (4)0.43309 (12)0.74768 (11)0.0518 (4)
H40.02150.46530.71510.062*
C60.1661 (3)0.30033 (10)0.81983 (10)0.0408 (4)
C70.0810 (3)0.21446 (11)0.84607 (11)0.0472 (4)
C130.0821 (4)0.18536 (12)1.08434 (11)0.0509 (4)
C160.0112 (5)0.26470 (15)1.12687 (15)0.0721 (7)
H16A0.09640.28231.16920.108*
H16B0.02870.31051.08740.108*
H16C0.16080.25191.15110.108*
C20.4428 (3)0.41823 (12)0.82025 (13)0.0527 (4)
H20.58680.44050.83680.063*
C10.3806 (3)0.33609 (11)0.84366 (12)0.0474 (4)
H10.48290.30380.87590.057*
C90.5540 (4)0.08701 (17)0.98774 (16)0.0755 (7)
H9A0.64270.09520.93800.113*
H9B0.63720.04861.02380.113*
H9C0.53220.14161.01470.113*
C150.3706 (4)0.07226 (13)1.06905 (11)0.0529 (5)
H150.51090.04751.08630.063*
C140.2906 (4)0.14736 (14)1.10736 (13)0.0574 (5)
H140.37960.17221.14920.069*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
N10.0503 (8)0.0419 (7)0.0706 (10)0.0063 (7)0.0069 (8)0.0095 (7)
N20.0532 (9)0.0386 (7)0.0638 (9)0.0062 (7)0.0056 (7)0.0055 (7)
C110.0551 (11)0.0474 (9)0.0529 (10)0.0027 (9)0.0118 (9)0.0072 (8)
O10.0552 (9)0.0525 (8)0.1078 (12)0.0153 (7)0.0246 (9)0.0154 (8)
C50.0450 (9)0.0491 (9)0.0489 (9)0.0012 (8)0.0064 (8)0.0028 (8)
C80.0472 (9)0.0423 (8)0.0455 (8)0.0025 (7)0.0007 (8)0.0019 (7)
C100.0446 (9)0.0428 (8)0.0429 (8)0.0027 (8)0.0001 (7)0.0014 (7)
C120.0513 (11)0.0527 (10)0.0632 (12)0.0089 (9)0.0074 (10)0.0053 (9)
N30.0756 (13)0.0518 (10)0.1198 (17)0.0061 (10)0.0042 (13)0.0306 (11)
C30.0549 (11)0.0407 (9)0.0585 (10)0.0024 (8)0.0096 (9)0.0037 (8)
C40.0553 (11)0.0483 (9)0.0518 (10)0.0099 (8)0.0029 (9)0.0057 (8)
C60.0417 (8)0.0383 (7)0.0424 (8)0.0001 (7)0.0012 (7)0.0031 (6)
C70.0500 (10)0.0391 (8)0.0527 (9)0.0048 (8)0.0078 (8)0.0021 (7)
C130.0527 (11)0.0493 (9)0.0507 (10)0.0021 (9)0.0060 (8)0.0079 (8)
C160.0745 (15)0.0686 (13)0.0731 (14)0.0103 (12)0.0057 (12)0.0248 (11)
C20.0418 (10)0.0453 (9)0.0709 (11)0.0054 (8)0.0022 (9)0.0010 (8)
C10.0417 (9)0.0418 (8)0.0586 (10)0.0006 (8)0.0083 (8)0.0035 (7)
C90.0624 (14)0.0771 (14)0.0870 (15)0.0209 (13)0.0199 (12)0.0280 (12)
C150.0447 (10)0.0606 (11)0.0534 (10)0.0010 (9)0.0079 (8)0.0058 (9)
C140.0545 (12)0.0640 (12)0.0536 (10)0.0040 (10)0.0068 (9)0.0161 (9)
Geometric parameters (Å, º) top
N1—C71.357 (2)C3—C21.391 (3)
N1—N21.388 (2)C3—C41.394 (3)
N1—H1N0.8600C4—H40.9300
N2—C81.281 (2)C6—C11.397 (2)
C11—C121.380 (3)C6—C71.478 (2)
C11—C101.395 (3)C13—C141.378 (3)
C11—H110.9300C13—C161.506 (3)
O1—C71.231 (2)C16—H16A0.9600
C5—C41.378 (2)C16—H16B0.9600
C5—C61.389 (2)C16—H16C0.9600
C5—H50.9300C2—C11.374 (3)
C8—C101.483 (2)C2—H20.9300
C8—C91.504 (3)C1—H10.9300
C10—C151.392 (3)C9—H9A0.9600
C12—C131.388 (3)C9—H9B0.9600
C12—H120.9300C9—H9C0.9600
N3—C31.365 (2)C15—C141.395 (3)
N3—H2N30.8600C15—H150.9300
N3—H1N30.8600C14—H140.9300
C7—N1—N2120.20 (17)O1—C7—N1121.87 (17)
C7—N1—H1N119.9O1—C7—C6122.06 (17)
N2—N1—H1N119.9N1—C7—C6116.05 (16)
C8—N2—N1116.05 (16)C14—C13—C12117.64 (17)
C12—C11—C10121.11 (18)C14—C13—C16121.95 (18)
C12—C11—H11119.4C12—C13—C16120.41 (19)
C10—C11—H11119.4C13—C16—H16A109.5
C4—C5—C6121.61 (18)C13—C16—H16B109.5
C4—C5—H5119.2H16A—C16—H16B109.5
C6—C5—H5119.2C13—C16—H16C109.5
N2—C8—C10116.57 (16)H16A—C16—H16C109.5
N2—C8—C9123.50 (17)H16B—C16—H16C109.5
C10—C8—C9119.90 (17)C1—C2—C3121.04 (17)
C15—C10—C11117.15 (17)C1—C2—H2119.5
C15—C10—C8122.29 (17)C3—C2—H2119.5
C11—C10—C8120.51 (16)C2—C1—C6121.12 (17)
C11—C12—C13121.66 (19)C2—C1—H1119.4
C11—C12—H12119.2C6—C1—H1119.4
C13—C12—H12119.2C8—C9—H9A109.5
C3—N3—H2N3120.0C8—C9—H9B109.5
C3—N3—H1N3120.0H9A—C9—H9B109.5
H2N3—N3—H1N3120.0C8—C9—H9C109.5
N3—C3—C2120.36 (19)H9A—C9—H9C109.5
N3—C3—C4121.45 (19)H9B—C9—H9C109.5
C2—C3—C4118.18 (16)C10—C15—C14121.25 (19)
C5—C4—C3120.48 (18)C10—C15—H15119.4
C5—C4—H4119.8C14—C15—H15119.4
C3—C4—H4119.8C13—C14—C15121.16 (18)
C5—C6—C1117.57 (15)C13—C14—H14119.4
C5—C6—C7118.01 (16)C15—C14—H14119.4
C1—C6—C7124.35 (15)
C7—N1—N2—C8166.25 (17)C5—C6—C7—O19.6 (3)
N2—N1—C7—O14.9 (3)C5—C6—C7—N1171.91 (16)
N2—N1—C7—C6173.63 (15)N2—C8—C10—C117.5 (3)
N1—N2—C8—C90.2 (3)N2—C8—C10—C15169.65 (18)
N1—N2—C8—C10178.39 (15)C9—C8—C10—C11174.22 (18)
C6—C1—C2—C30.1 (3)C9—C8—C10—C158.6 (3)
C2—C1—C6—C50.2 (3)C8—C10—C11—C12176.11 (18)
C2—C1—C6—C7176.59 (17)C15—C10—C11—C121.2 (3)
C1—C2—C3—N3179.6 (2)C8—C10—C15—C14176.54 (18)
C1—C2—C3—C40.5 (3)C11—C10—C15—C140.7 (3)
N3—C3—C4—C5179.5 (2)C10—C11—C12—C130.1 (3)
C2—C3—C4—C50.6 (3)C11—C12—C13—C141.4 (3)
C3—C4—C5—C60.4 (3)C11—C12—C13—C16178.4 (2)
C4—C5—C6—C10.1 (3)C12—C13—C14—C151.9 (3)
C4—C5—C6—C7176.93 (17)C16—C13—C14—C15177.9 (2)
C1—C6—C7—O1167.14 (18)C13—C14—C15—C100.9 (3)
C1—C6—C7—N111.3 (3)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N3—H1N3···O1i0.862.102.914 (2)159
C9—H9A···O1ii0.962.603.475 (3)152
Symmetry codes: (i) x, y+1/2, z+3/2; (ii) x+1, y, z.
 

Acknowledgements

PS and KB thank the Department of Science and Technology (DST–SERB), grant No. SB/FT/CS-058/2013, New Delhi, India, for financial support.

References

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