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

Sivajeyanthi, P.; Jeevaraj, M.; Edison, B.; Balasubramani, K.

doi:10.1107/S205698901700857X

research communications

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ISSN: 2056-9890

Volume 73| Part 7| July 2017| Pages 1029-1032

https://doi.org/10.1107/S205698901700857X

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

Palaniyappan Sivajeyanthi,^a Muthaiah Jeevaraj,^a Bellarmin Edison ^a and Kasthuri Balasubramani ^a ^*

^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.

Keywords: crystal structure; Schiff base; substituted benzohydrazide; hydrogen bonding; Hirshfeld surface analysis.

CCDC reference: 1554995

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 ; Khattab et al., 2005 ; Küçükgüzel et al., 2006 ). Hydrazone Schiff base compounds (Cao et al., 2009 ; Zhou & Yang, 2010 ; Zhang et al., 2009 ), 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 ; Armstrong et al., 2003 ). 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.

2. Structural commentary

The asymmetric unit of the title compound contains one independent molecule (Fig. 1), 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
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). 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. The secondary weak methyl C9—H9A⋯O1ⁱⁱ hydrogen-bonding interactions extend the structure across a (Fig. 3), 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	D⋯A	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
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
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 ) have been used to quantify the various intermolecular interactions in the title compound. The Hirshfeld surface of a molecule is mapped using the descriptor d_norm which encompasses two factors: one is d_e, representing the distance of any surface point nearest to the internal atoms, and the other one is d_i, 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 ). The Hirshfeld surfaces mapped over d_norm (range of −0.502–1.427 Å) are displayed in Fig. 4. 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). Other visible spots in the Hirshfeld surfaces correspond to C—H and H—H contacts.

Figure 4
Hirshfeld surfaces mapped over d_norm for the title compound.

The intermolecular interactions of the title compound are shown in the 2D fingerprint plots shown in Fig. 5. 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 d_e and d_i, are displayed in Fig. 6.

Figure 5
Two-dimensional fingerprint plots of the title compound.

Figure 6
Two-dimensional fingerprint plots with a d_norm 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. 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 U_iso(H) = 1.2 U_eq(N, C) or 1.5U_eq(methyl C). One reflection (011) was considered to be affected by the beamstop.

Table 2
Experimental details

Crystal data
Chemical formula	C₁₆H₁₇N₃O
M_r	267.33
Crystal system, space group	Orthorhombic, P2₁2₁2₁
Temperature (K)	296
a, b, c (Å)	5.7011 (4), 15.4836 (10), 16.2128 (10)
V (Å³)	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 )
T_min, T_max	0.976, 0.984
No. of measured, independent and observed [I > 2σ(I)] reflections	17427, 3501, 2784
R_int	0.027
(sin θ/λ)_max (Å⁻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
Δρ_max, Δρ_min (e Å⁻³)	0.17, −0.20
Absolute structure	Flack (1983 ), 1489 Friedel pairs
Absolute structure parameter	0.6 (19)
Computer programs: APEX2 (Bruker, 2004), APEX2, SAINT and XPREP (Bruker, 2004), SIR92 (Altomare et al., 1993 ), SHELXL97 (Sheldrick, 2008 ), ORTEP-3 for Windows (Farrugia, 2012 ) and Mercury (Macrae et al., 2008 ).

Supporting information

CCDC reference: 1554995

Crystal structure: contains datablocks global, I. DOI: https://doi.org/10.1107/S205698901700857X/zs2381sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S205698901700857X/zs2381Isup2.hkl

Supporting information file. DOI: https://doi.org/10.1107/S205698901700857X/zs2381Isup3.cml

checkCIF report

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

C₁₆H₁₇N₃O	F(000) = 568
M_r = 267.33	D_x = 1.241 Mg m⁻³
Orthorhombic, P2₁2₁2₁	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ac 2ab	Cell parameters from 6816 reflections
a = 5.7011 (4) Å	θ = 5.0–49.0°
b = 15.4836 (10) Å	µ = 0.08 mm⁻¹
c = 16.2128 (10) Å	T = 296 K
V = 1431.16 (16) Å³	Block, colorless
Z = 4	0.30 × 0.20 × 0.20 mm

Data collection top

Bruker Kappa APEXII CCD diffractometer	3501 independent reflections
Radiation source: fine-focus sealed tube	2784 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.027
ω and φ scan	θ_max = 28.3°, θ_min = 1.8°
Absorption correction: multi-scan (SADABS; Bruker, 2004)	h = −7→7
T_min = 0.976, T_max = 0.984	k = −17→20
17427 measured reflections	l = −21→21

Refinement top

Refinement on F²	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F² > 2σ(F²)] = 0.045	H-atom parameters constrained
wR(F²) = 0.141	w = 1/[σ²(F_o²) + (0.0847P)² + 0.1161P] where P = (F_o² + 2F_c²)/3
S = 1.05	(Δ/σ)_max < 0.001
3501 reflections	Δρ_max = 0.17 e Å⁻³
182 parameters	Δρ_min = −0.20 e Å⁻³
0 restraints	Absolute structure: Flack (1983), 1489 Friedel pairs
Primary atom site location: structure-invariant direct methods	Absolute 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

	x	y	z	U_iso*/U_eq
N1	0.2405 (3)	0.16299 (10)	0.88410 (10)	0.0543 (4)
H1N	0.3848	0.1789	0.8871	0.065*
N2	0.1715 (3)	0.08479 (10)	0.91817 (10)	0.0519 (4)
C11	0.0364 (4)	−0.07382 (12)	0.98126 (12)	0.0518 (5)
H11	−0.0509	−0.0504	0.9383	0.062*
O1	−0.1236 (3)	0.19158 (9)	0.83572 (11)	0.0718 (5)
C5	0.0187 (3)	0.35074 (11)	0.77149 (11)	0.0477 (4)
H5	−0.1250	0.3283	0.7548	0.057*
C8	0.3188 (3)	0.04879 (11)	0.96690 (11)	0.0450 (4)
C10	0.2444 (3)	−0.03365 (11)	1.00549 (10)	0.0434 (4)
C12	−0.0420 (4)	−0.14777 (12)	1.02002 (12)	0.0557 (5)
H12	−0.1814	−0.1730	1.0026	0.067*
N3	0.3577 (4)	0.55025 (11)	0.74979 (15)	0.0824 (6)
H2N3	0.4905	0.5709	0.7654	0.099*
H1N3	0.2650	0.5811	0.7201	0.099*
C3	0.2940 (4)	0.46854 (11)	0.77215 (12)	0.0514 (4)
C4	0.0803 (4)	0.43309 (12)	0.74768 (11)	0.0518 (4)
H4	−0.0215	0.4653	0.7151	0.062*
C6	0.1661 (3)	0.30033 (10)	0.81983 (10)	0.0408 (4)
C7	0.0810 (3)	0.21446 (11)	0.84607 (11)	0.0472 (4)
C13	0.0821 (4)	−0.18536 (12)	1.08434 (11)	0.0509 (4)
C16	−0.0112 (5)	−0.26470 (15)	1.12687 (15)	0.0721 (7)
H16A	0.0964	−0.2823	1.1692	0.108*
H16B	−0.0287	−0.3105	1.0874	0.108*
H16C	−0.1608	−0.2519	1.1511	0.108*
C2	0.4428 (3)	0.41823 (12)	0.82025 (13)	0.0527 (4)
H2	0.5868	0.4405	0.8368	0.063*
C1	0.3806 (3)	0.33609 (11)	0.84366 (12)	0.0474 (4)
H1	0.4829	0.3038	0.8759	0.057*
C9	0.5540 (4)	0.08701 (17)	0.98774 (16)	0.0755 (7)
H9A	0.6427	0.0952	0.9380	0.113*
H9B	0.6372	0.0486	1.0238	0.113*
H9C	0.5322	0.1416	1.0147	0.113*
C15	0.3706 (4)	−0.07226 (13)	1.06905 (11)	0.0529 (5)
H15	0.5109	−0.0475	1.0863	0.063*
C14	0.2906 (4)	−0.14736 (14)	1.10736 (13)	0.0574 (5)
H14	0.3796	−0.1722	1.1492	0.069*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
N1	0.0503 (8)	0.0419 (7)	0.0706 (10)	−0.0063 (7)	−0.0069 (8)	0.0095 (7)
N2	0.0532 (9)	0.0386 (7)	0.0638 (9)	−0.0062 (7)	−0.0056 (7)	0.0055 (7)
C11	0.0551 (11)	0.0474 (9)	0.0529 (10)	−0.0027 (9)	−0.0118 (9)	0.0072 (8)
O1	0.0552 (9)	0.0525 (8)	0.1078 (12)	−0.0153 (7)	−0.0246 (9)	0.0154 (8)
C5	0.0450 (9)	0.0491 (9)	0.0489 (9)	0.0012 (8)	−0.0064 (8)	−0.0028 (8)
C8	0.0472 (9)	0.0423 (8)	0.0455 (8)	−0.0025 (7)	0.0007 (8)	−0.0019 (7)
C10	0.0446 (9)	0.0428 (8)	0.0429 (8)	0.0027 (8)	−0.0001 (7)	−0.0014 (7)
C12	0.0513 (11)	0.0527 (10)	0.0632 (12)	−0.0089 (9)	−0.0074 (10)	0.0053 (9)
N3	0.0756 (13)	0.0518 (10)	0.1198 (17)	−0.0061 (10)	−0.0042 (13)	0.0306 (11)
C3	0.0549 (11)	0.0407 (9)	0.0585 (10)	0.0024 (8)	0.0096 (9)	0.0037 (8)
C4	0.0553 (11)	0.0483 (9)	0.0518 (10)	0.0099 (8)	−0.0029 (9)	0.0057 (8)
C6	0.0417 (8)	0.0383 (7)	0.0424 (8)	−0.0001 (7)	−0.0012 (7)	−0.0031 (6)
C7	0.0500 (10)	0.0391 (8)	0.0527 (9)	−0.0048 (8)	−0.0078 (8)	−0.0021 (7)
C13	0.0527 (11)	0.0493 (9)	0.0507 (10)	0.0021 (9)	0.0060 (8)	0.0079 (8)
C16	0.0745 (15)	0.0686 (13)	0.0731 (14)	−0.0103 (12)	0.0057 (12)	0.0248 (11)
C2	0.0418 (10)	0.0453 (9)	0.0709 (11)	−0.0054 (8)	−0.0022 (9)	0.0010 (8)
C1	0.0417 (9)	0.0418 (8)	0.0586 (10)	0.0006 (8)	−0.0083 (8)	0.0035 (7)
C9	0.0624 (14)	0.0771 (14)	0.0870 (15)	−0.0209 (13)	−0.0199 (12)	0.0280 (12)
C15	0.0447 (10)	0.0606 (11)	0.0534 (10)	−0.0010 (9)	−0.0079 (8)	0.0058 (9)
C14	0.0545 (12)	0.0640 (12)	0.0536 (10)	0.0040 (10)	−0.0068 (9)	0.0161 (9)

Geometric parameters (Å, º) top

N1—C7	1.357 (2)	C3—C2	1.391 (3)
N1—N2	1.388 (2)	C3—C4	1.394 (3)
N1—H1N	0.8600	C4—H4	0.9300
N2—C8	1.281 (2)	C6—C1	1.397 (2)
C11—C12	1.380 (3)	C6—C7	1.478 (2)
C11—C10	1.395 (3)	C13—C14	1.378 (3)
C11—H11	0.9300	C13—C16	1.506 (3)
O1—C7	1.231 (2)	C16—H16A	0.9600
C5—C4	1.378 (2)	C16—H16B	0.9600
C5—C6	1.389 (2)	C16—H16C	0.9600
C5—H5	0.9300	C2—C1	1.374 (3)
C8—C10	1.483 (2)	C2—H2	0.9300
C8—C9	1.504 (3)	C1—H1	0.9300
C10—C15	1.392 (3)	C9—H9A	0.9600
C12—C13	1.388 (3)	C9—H9B	0.9600
C12—H12	0.9300	C9—H9C	0.9600
N3—C3	1.365 (2)	C15—C14	1.395 (3)
N3—H2N3	0.8600	C15—H15	0.9300
N3—H1N3	0.8600	C14—H14	0.9300

C7—N1—N2	120.20 (17)	O1—C7—N1	121.87 (17)
C7—N1—H1N	119.9	O1—C7—C6	122.06 (17)
N2—N1—H1N	119.9	N1—C7—C6	116.05 (16)
C8—N2—N1	116.05 (16)	C14—C13—C12	117.64 (17)
C12—C11—C10	121.11 (18)	C14—C13—C16	121.95 (18)
C12—C11—H11	119.4	C12—C13—C16	120.41 (19)
C10—C11—H11	119.4	C13—C16—H16A	109.5
C4—C5—C6	121.61 (18)	C13—C16—H16B	109.5
C4—C5—H5	119.2	H16A—C16—H16B	109.5
C6—C5—H5	119.2	C13—C16—H16C	109.5
N2—C8—C10	116.57 (16)	H16A—C16—H16C	109.5
N2—C8—C9	123.50 (17)	H16B—C16—H16C	109.5
C10—C8—C9	119.90 (17)	C1—C2—C3	121.04 (17)
C15—C10—C11	117.15 (17)	C1—C2—H2	119.5
C15—C10—C8	122.29 (17)	C3—C2—H2	119.5
C11—C10—C8	120.51 (16)	C2—C1—C6	121.12 (17)
C11—C12—C13	121.66 (19)	C2—C1—H1	119.4
C11—C12—H12	119.2	C6—C1—H1	119.4
C13—C12—H12	119.2	C8—C9—H9A	109.5
C3—N3—H2N3	120.0	C8—C9—H9B	109.5
C3—N3—H1N3	120.0	H9A—C9—H9B	109.5
H2N3—N3—H1N3	120.0	C8—C9—H9C	109.5
N3—C3—C2	120.36 (19)	H9A—C9—H9C	109.5
N3—C3—C4	121.45 (19)	H9B—C9—H9C	109.5
C2—C3—C4	118.18 (16)	C10—C15—C14	121.25 (19)
C5—C4—C3	120.48 (18)	C10—C15—H15	119.4
C5—C4—H4	119.8	C14—C15—H15	119.4
C3—C4—H4	119.8	C13—C14—C15	121.16 (18)
C5—C6—C1	117.57 (15)	C13—C14—H14	119.4
C5—C6—C7	118.01 (16)	C15—C14—H14	119.4
C1—C6—C7	124.35 (15)

C7—N1—N2—C8	−166.25 (17)	C5—C6—C7—O1	−9.6 (3)
N2—N1—C7—O1	−4.9 (3)	C5—C6—C7—N1	171.91 (16)
N2—N1—C7—C6	173.63 (15)	N2—C8—C10—C11	7.5 (3)
N1—N2—C8—C9	0.2 (3)	N2—C8—C10—C15	−169.65 (18)
N1—N2—C8—C10	178.39 (15)	C9—C8—C10—C11	−174.22 (18)
C6—C1—C2—C3	0.1 (3)	C9—C8—C10—C15	8.6 (3)
C2—C1—C6—C5	0.2 (3)	C8—C10—C11—C12	−176.11 (18)
C2—C1—C6—C7	−176.59 (17)	C15—C10—C11—C12	1.2 (3)
C1—C2—C3—N3	179.6 (2)	C8—C10—C15—C14	176.54 (18)
C1—C2—C3—C4	−0.5 (3)	C11—C10—C15—C14	−0.7 (3)
N3—C3—C4—C5	−179.5 (2)	C10—C11—C12—C13	−0.1 (3)
C2—C3—C4—C5	0.6 (3)	C11—C12—C13—C14	−1.4 (3)
C3—C4—C5—C6	−0.4 (3)	C11—C12—C13—C16	178.4 (2)
C4—C5—C6—C1	−0.1 (3)	C12—C13—C14—C15	1.9 (3)
C4—C5—C6—C7	176.93 (17)	C16—C13—C14—C15	−177.9 (2)
C1—C6—C7—O1	167.14 (18)	C13—C14—C15—C10	−0.9 (3)
C1—C6—C7—N1	−11.3 (3)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	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+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.

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