1,2-Bis(2-hy­droxy-5-methyl­benzyl­idene)hydrazine

Saravanan, B.; Jayamani, A.; Sengottuvelan, N.; Chakkaravarthi, G.; Manivannan, V.

doi:10.1107/S160053681302148X

organic compounds

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ISSN: 2056-9890

Volume 69| Part 9| September 2013| Pages o1394-o1395

doi:10.1107/S160053681302148X

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1,2-Bis(2-hydroxy-5-methylbenzylidene)hydrazine

B. Saravanan,^a A. Jayamani,^b N. Sengottuvelan,^b G. Chakkaravarthi ^c ^* and V. Manivannan ^a ^*

^aCentre for Research and Development, PRIST University, Vallam, Thanjavur 613 403, India, ^bDepartment of Chemistry, DDE, Alagappa University, Karaikudi 630 003, India, and ^cDepartment of Physics, CPCL Polytechnic College, Chennai 600 068, India
^*Correspondence e-mail: chakkaravarthi_2005@yahoo.com, crystallography2010@gmail.com

(Received 27 July 2013; accepted 1 August 2013; online 7 August 2013)

The molecular structure of the title compound, C₁₆H₁₆N₂O₂, is stabilized by intramolecular O—H⋯N hydrogen bonds with S(6) graph-set motifs, so that the molecule is almost planar, with a C=N—N=C torsion angle of −179.7 (2)° and a dihedral angle of 1.82 (12)° between the aromatic rings. In the crystal, weak C—H⋯π interactions lead to the formation of a three-dimensional network.

Related literature

For the biological activity of Schiff base ligands, see: Kelley et al. (1995 ); Pandeya et al. (1999 ); Singh & Dash (1988 ); Tarafder et al. (2002 ). For standard bond lengths, see: Allen et al. (1987 ). For related strucutures, see: Chantrapromma et al. (2010 ); Fun et al. (2010 ). For graph-set motifs, see: Bernstein et al. (1995 ).

Experimental

Crystal data

C₁₆H₁₆N₂O₂
M_r = 268.31
Orthorhombic, P 2₁ 2₁ 2₁
a = 6.0108 (5) Å
b = 7.3394 (5) Å
c = 31.674 (2) Å
V = 1397.32 (17) Å³
Z = 4
Mo Kα radiation
μ = 0.09 mm⁻¹
T = 295 K
0.22 × 0.18 × 0.16 mm

Data collection

Bruker Kappa APEXII diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 1996 ) T_min = 0.982, T_max = 0.987
5699 measured reflections
2952 independent reflections
1780 reflections with I > 2σ(I)
R_int = 0.023

Refinement

R[F² > 2σ(F²)] = 0.050
wR(F²) = 0.154
S = 1.02
2952 reflections
185 parameters
H-atom parameters constrained
Δρ_max = 0.17 e Å⁻³
Δρ_min = −0.17 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

Cg1 and Cg2 are the centroids of the C1–C6 and C10–C15 rings, respectively.

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O2—H2A⋯N2	0.82	1.91	2.635 (3)	146
O1—H1⋯N1	0.82	1.93	2.646 (3)	145
C5—H5⋯Cg1ⁱ	0.93	2.84	3.519 (3)	130
C14—H14⋯Cg2ⁱⁱ	0.93	2.85	3.519 (3)	130
Symmetry codes: (i) $[-x-1, y-{\script{1\over 2}}, -z+{\script{1\over 2}}]$ ; (ii) $[x+{\script{1\over 2}}, -y+{\script{5\over 2}}, -z+1]$ .

Data collection: APEX2 (Bruker, 2004 ); cell refinement: SAINT (Bruker, 2004); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: PLATON (Spek, 2009 ); software used to prepare material for publication: SHELXL97.

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S160053681302148X/is5296sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S160053681302148X/is5296Isup2.hkl

Supporting information file. DOI: 10.1107/S160053681302148X/is5296Isup3.cml

checkCIF report

Comment top

Schiff base ligands exhibit anti-cancer, anti-fungal, anti-tumour and anti-HIV activities (Pandeya et al., 1999; Singh & Dash, 1988; Kelley et al., 1995; Tarafder et al., 2002). In the molecular structure of the title compound (Fig. 1), the bond distances are within the normal range (Allen et al., 1987) and are comparable with the related structures (Chantrapromma et al., 2010; Fun et al., 2010). In the molecule, two aromatic rings are almost co-planar, with a dihedral angle of 1.82 (12)°. The hydroxy groups form intramolecular O—H···N hydrogen bonds (O1—H1···N1 and O2—H2A···N2; Table 1) with S(6) graph-set motifs (Bernstein et al., 1995). The crystal structure also exhibits weak intermolecular C—H···π (Table 1) interactions which forms a three dimensional network.

Related literature top

For the biological activity of Schiff base ligands, see: Kelley et al. (1995); Pandeya et al. (1999); Singh & Dash (1988); Tarafder et al. (2002). For standard bond lengths, see: Allen et al. (1987). For related strucutures, see: Chantrapromma et al. (2010); Fun et al. (2010). For graph-set motifs, see: Bernstein et al. (1995).

Experimental top

The title compound was synthesized by mixing a solution (1:2 molar ratio) of hydrazine hydrate (0.20 ml, 4 mmol) and 2-hydroxy-5-methylbenzaldehyde (1.08 g, 8 mmol) in ethanol (30 ml). The resulting solution was refluxed for 4 h, yielding (65%) the pale yellow crystalline solid. The resultant solid was filtered off and washed with methanol. Pale Yellow single crystals of the title compound suitable for X-ray structure determination were recrystalized from dimethylformamide by slow evaporation at room temperature over several days.

Computing details top

Data collection: APEX2 (Bruker, 2004); cell refinement: SAINT (Bruker, 2004); data reduction: SAINT (Bruker, 2004); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: PLATON (Spek, 2009); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top

Fig. 1. The molecular structure of the title compound, with atom labels and 30% probability displacement ellipsoids for non-H atoms.

2-{[2-(2-Hydroxy-5-methylbenzylidene)hydrazin-1-ylidene]methyl}-4-methylphenol top

Crystal data top

C₁₆H₁₆N₂O₂	F(000) = 568
M_r = 268.31	D_x = 1.275 Mg m⁻³
Orthorhombic, P2₁2₁2₁	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ac 2ab	Cell parameters from 2658 reflections
a = 6.0108 (5) Å	θ = 2.4–27.2°
b = 7.3394 (5) Å	µ = 0.09 mm⁻¹
c = 31.674 (2) Å	T = 295 K
V = 1397.32 (17) Å³	Block, yellow
Z = 4	0.22 × 0.18 × 0.16 mm

Data collection top

Bruker Kappa APEXII diffractometer	2952 independent reflections
Radiation source: fine-focus sealed tube	1780 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.023
ω and ϕ scans	θ_max = 27.2°, θ_min = 2.6°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	h = −6→7
T_min = 0.982, T_max = 0.987	k = −9→9
5699 measured reflections	l = −40→39

Refinement top

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)] = 0.050	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.154	H-atom parameters constrained
S = 1.02	w = 1/[σ²(F_o²) + (0.0788P)²] where P = (F_o² + 2F_c²)/3
2952 reflections	(Δ/σ)_max < 0.001
185 parameters	Δρ_max = 0.17 e Å⁻³
0 restraints	Δρ_min = −0.17 e Å⁻³

Crystal data top

C₁₆H₁₆N₂O₂	V = 1397.32 (17) Å³
M_r = 268.31	Z = 4
Orthorhombic, P2₁2₁2₁	Mo Kα radiation
a = 6.0108 (5) Å	µ = 0.09 mm⁻¹
b = 7.3394 (5) Å	T = 295 K
c = 31.674 (2) Å	0.22 × 0.18 × 0.16 mm

Data collection top

Bruker Kappa APEXII diffractometer	2952 independent reflections
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	1780 reflections with I > 2σ(I)
T_min = 0.982, T_max = 0.987	R_int = 0.023
5699 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.050	0 restraints
wR(F²) = 0.154	H-atom parameters constrained
S = 1.02	Δρ_max = 0.17 e Å⁻³
2952 reflections	Δρ_min = −0.17 e Å⁻³
185 parameters

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
C1	−0.1393 (4)	0.8872 (3)	0.28106 (7)	0.0424 (6)
C2	−0.0535 (4)	0.9211 (3)	0.24097 (7)	0.0467 (6)
H2	0.0874	0.9726	0.2387	0.056*
C3	−0.1689 (5)	0.8812 (4)	0.20427 (8)	0.0528 (7)
C4	−0.3790 (5)	0.8051 (4)	0.20879 (8)	0.0558 (7)
H4	−0.4604	0.7765	0.1847	0.067*
C5	−0.4700 (5)	0.7708 (3)	0.24753 (9)	0.0540 (7)
H5	−0.6106	0.7185	0.2493	0.065*
C6	−0.3559 (4)	0.8129 (4)	0.28389 (8)	0.0474 (7)
C7	−0.0682 (6)	0.9219 (4)	0.16150 (7)	0.0766 (10)
H7A	−0.0947	0.8212	0.1428	0.115*
H7B	0.0891	0.9405	0.1645	0.115*
H7C	−0.1352	1.0299	0.1500	0.115*
C8	−0.0071 (4)	0.9275 (3)	0.31799 (7)	0.0454 (6)
H8	0.1363	0.9726	0.3145	0.055*
C9	−0.0019 (4)	0.9213 (3)	0.42464 (7)	0.0451 (6)
H9	−0.1451	0.8758	0.4282	0.054*
C10	0.1302 (5)	0.9612 (3)	0.46142 (7)	0.0429 (6)
C11	0.0395 (5)	0.9322 (3)	0.50158 (7)	0.0478 (7)
H11	−0.1016	0.8810	0.5035	0.057*
C12	0.1501 (5)	0.9762 (3)	0.53841 (8)	0.0527 (7)
C13	0.3625 (6)	1.0501 (4)	0.53396 (8)	0.0578 (8)
H13	0.4417	1.0814	0.5581	0.069*
C14	0.4593 (5)	1.0786 (4)	0.49519 (8)	0.0556 (7)
H14	0.6019	1.1271	0.4935	0.067*
C15	0.3451 (5)	1.0352 (3)	0.45871 (8)	0.0460 (6)
C16	0.0438 (6)	0.9530 (4)	0.58087 (8)	0.0718 (9)
H16A	−0.0435	1.0588	0.5874	0.108*
H16B	0.1573	0.9378	0.6019	0.108*
H16C	−0.0504	0.8474	0.5805	0.108*
N1	−0.0818 (3)	0.9027 (3)	0.35543 (6)	0.0498 (6)
N2	0.0716 (4)	0.9465 (3)	0.38727 (6)	0.0498 (6)
O1	−0.4551 (3)	0.7801 (3)	0.32150 (5)	0.0680 (6)
H1	−0.3751	0.8171	0.3406	0.102*
O2	0.4451 (3)	1.0657 (3)	0.42094 (6)	0.0650 (6)
H2A	0.3623	1.0328	0.4018	0.098*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C1	0.0381 (15)	0.0357 (12)	0.0534 (14)	0.0023 (12)	−0.0003 (12)	0.0034 (10)
C2	0.0442 (15)	0.0392 (13)	0.0565 (16)	0.0000 (13)	−0.0007 (12)	0.0069 (11)
C3	0.0594 (19)	0.0491 (15)	0.0499 (15)	0.0053 (16)	−0.0034 (13)	0.0016 (12)
C4	0.0553 (19)	0.0488 (15)	0.0633 (17)	0.0011 (16)	−0.0152 (15)	−0.0051 (13)
C5	0.0412 (15)	0.0494 (14)	0.0715 (17)	−0.0039 (14)	−0.0070 (15)	−0.0016 (14)
C6	0.0417 (16)	0.0458 (14)	0.0548 (15)	0.0020 (14)	0.0002 (13)	0.0028 (11)
C7	0.102 (3)	0.076 (2)	0.0512 (16)	−0.006 (2)	−0.0028 (17)	0.0065 (14)
C8	0.0386 (16)	0.0415 (13)	0.0562 (15)	−0.0024 (13)	−0.0057 (12)	0.0003 (12)
C9	0.0395 (15)	0.0413 (13)	0.0546 (14)	−0.0010 (13)	0.0000 (12)	0.0035 (11)
C10	0.0412 (17)	0.0358 (12)	0.0518 (14)	0.0041 (12)	−0.0031 (12)	0.0002 (10)
C11	0.0465 (17)	0.0399 (13)	0.0570 (15)	0.0003 (13)	−0.0003 (13)	0.0042 (12)
C12	0.058 (2)	0.0425 (14)	0.0572 (16)	0.0059 (15)	−0.0035 (14)	0.0008 (12)
C13	0.061 (2)	0.0471 (15)	0.0656 (18)	0.0036 (16)	−0.0186 (15)	−0.0005 (13)
C14	0.0401 (17)	0.0508 (15)	0.0759 (19)	−0.0037 (15)	−0.0086 (14)	0.0047 (14)
C15	0.0379 (16)	0.0436 (14)	0.0564 (15)	−0.0008 (13)	−0.0007 (13)	0.0036 (12)
C16	0.091 (3)	0.0697 (18)	0.0550 (16)	0.005 (2)	0.0022 (17)	0.0006 (14)
N1	0.0458 (13)	0.0551 (13)	0.0485 (11)	−0.0018 (12)	−0.0044 (10)	0.0023 (10)
N2	0.0476 (13)	0.0490 (12)	0.0527 (11)	−0.0004 (11)	−0.0053 (11)	0.0021 (9)
O1	0.0460 (12)	0.0922 (16)	0.0658 (12)	−0.0134 (12)	0.0067 (10)	0.0055 (12)
O2	0.0490 (12)	0.0778 (14)	0.0683 (11)	−0.0112 (12)	0.0037 (10)	0.0053 (11)

Geometric parameters (Å, º) top

C1—C2	1.393 (3)	C9—H9	0.9300
C1—C6	1.415 (3)	C10—C11	1.400 (3)
C1—C8	1.445 (3)	C10—C15	1.404 (3)
C2—C3	1.385 (3)	C11—C12	1.381 (3)
C2—H2	0.9300	C11—H11	0.9300
C3—C4	1.388 (4)	C12—C13	1.395 (4)
C3—C7	1.514 (3)	C12—C16	1.499 (3)
C4—C5	1.367 (4)	C13—C14	1.375 (4)
C4—H4	0.9300	C13—H13	0.9300
C5—C6	1.376 (3)	C14—C15	1.381 (3)
C5—H5	0.9300	C14—H14	0.9300
C6—O1	1.354 (3)	C15—O2	1.357 (3)
C7—H7A	0.9600	C16—H16A	0.9600
C7—H7B	0.9600	C16—H16B	0.9600
C7—H7C	0.9600	C16—H16C	0.9600
C8—N1	1.281 (3)	N1—N2	1.404 (3)
C8—H8	0.9300	O1—H1	0.8200
C9—N2	1.277 (3)	O2—H2A	0.8200
C9—C10	1.440 (3)

C2—C1—C6	117.9 (2)	C10—C9—H9	119.0
C2—C1—C8	119.9 (2)	C11—C10—C15	118.2 (2)
C6—C1—C8	122.3 (2)	C11—C10—C9	119.3 (3)
C3—C2—C1	122.8 (2)	C15—C10—C9	122.5 (2)
C3—C2—H2	118.6	C12—C11—C10	123.0 (3)
C1—C2—H2	118.6	C12—C11—H11	118.5
C2—C3—C4	117.0 (2)	C10—C11—H11	118.5
C2—C3—C7	120.6 (3)	C11—C12—C13	116.5 (3)
C4—C3—C7	122.4 (3)	C11—C12—C16	121.8 (3)
C5—C4—C3	122.0 (3)	C13—C12—C16	121.7 (3)
C5—C4—H4	119.0	C14—C13—C12	122.5 (3)
C3—C4—H4	119.0	C14—C13—H13	118.8
C4—C5—C6	120.7 (3)	C12—C13—H13	118.8
C4—C5—H5	119.6	C13—C14—C15	120.1 (3)
C6—C5—H5	119.6	C13—C14—H14	119.9
O1—C6—C5	118.5 (2)	C15—C14—H14	119.9
O1—C6—C1	122.0 (2)	O2—C15—C14	118.6 (3)
C5—C6—C1	119.5 (2)	O2—C15—C10	121.7 (2)
C3—C7—H7A	109.5	C14—C15—C10	119.7 (2)
C3—C7—H7B	109.5	C12—C16—H16A	109.5
H7A—C7—H7B	109.5	C12—C16—H16B	109.5
C3—C7—H7C	109.5	H16A—C16—H16B	109.5
H7A—C7—H7C	109.5	C12—C16—H16C	109.5
H7B—C7—H7C	109.5	H16A—C16—H16C	109.5
N1—C8—C1	121.8 (2)	H16B—C16—H16C	109.5
N1—C8—H8	119.1	C8—N1—N2	113.7 (2)
C1—C8—H8	119.1	C9—N2—N1	113.9 (2)
N2—C9—C10	122.0 (2)	C6—O1—H1	109.5
N2—C9—H9	119.0	C15—O2—H2A	109.5

C6—C1—C2—C3	−1.5 (4)	C15—C10—C11—C12	1.3 (4)
C8—C1—C2—C3	178.2 (2)	C9—C10—C11—C12	−176.3 (2)
C1—C2—C3—C4	0.3 (4)	C10—C11—C12—C13	−0.9 (4)
C1—C2—C3—C7	179.6 (2)	C10—C11—C12—C16	176.6 (2)
C2—C3—C4—C5	0.2 (4)	C11—C12—C13—C14	0.0 (4)
C7—C3—C4—C5	−179.1 (3)	C16—C12—C13—C14	−177.6 (2)
C3—C4—C5—C6	0.7 (4)	C12—C13—C14—C15	0.6 (4)
C4—C5—C6—O1	178.5 (2)	C13—C14—C15—O2	179.7 (2)
C4—C5—C6—C1	−1.9 (4)	C13—C14—C15—C10	−0.3 (4)
C2—C1—C6—O1	−178.2 (2)	C11—C10—C15—O2	179.4 (2)
C8—C1—C6—O1	2.1 (4)	C9—C10—C15—O2	−3.1 (4)
C2—C1—C6—C5	2.3 (4)	C11—C10—C15—C14	−0.6 (3)
C8—C1—C6—C5	−177.4 (2)	C9—C10—C15—C14	176.9 (2)
C2—C1—C8—N1	178.2 (2)	C1—C8—N1—N2	179.0 (2)
C6—C1—C8—N1	−2.0 (4)	C10—C9—N2—N1	−179.07 (19)
N2—C9—C10—C11	179.4 (2)	C8—N1—N2—C9	−179.7 (2)
N2—C9—C10—C15	2.0 (4)

Hydrogen-bond geometry (Å, º) top

Cg1 and Cg2 are the centroids of the C1–C6 and C10–C15 rings, respectively.

D—H···A	D—H	H···A	D···A	D—H···A
O2—H2A···N2	0.82	1.91	2.635 (3)	146
O1—H1···N1	0.82	1.93	2.646 (3)	145
C5—H5···Cg1ⁱ	0.93	2.84	3.519 (3)	130
C14—H14···Cg2ⁱⁱ	0.93	2.85	3.519 (3)	130

Symmetry codes: (i) −x−1, y−1/2, −z+1/2; (ii) x+1/2, −y+5/2, −z+1.

Hydrogen-bond geometry (Å, º) top

Cg1 and Cg2 are the centroids of the C1–C6 and C10–C15 rings, respectively.

D—H···A	D—H	H···A	D···A	D—H···A
O2—H2A···N2	0.82	1.91	2.635 (3)	146
O1—H1···N1	0.82	1.93	2.646 (3)	145
C5—H5···Cg1ⁱ	0.93	2.84	3.519 (3)	130
C14—H14···Cg2ⁱⁱ	0.93	2.85	3.519 (3)	130

Symmetry codes: (i) −x−1, y−1/2, −z+1/2; (ii) x+1/2, −y+5/2, −z+1.

Acknowledgements

The authors acknowledge the Department of Chemistry, IIT Madras, for the data collection.

References

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Volume 69| Part 9| September 2013| Pages o1394-o1395

doi:10.1107/S160053681302148X

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