4-[1-(Hydroxy­imino)ethyl]-N-(4-nitro­benzyl­idene)aniline

Zhao, L.; Dong, W.-K.; Wu, J.-C.; Sun, Y.-X.; Xu, L.

doi:10.1107/S1600536809033753

organic compounds

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ISSN: 2056-9890

Volume 65| Part 10| October 2009| Page o2462

doi:10.1107/S1600536809033753

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4-[1-(Hydroxyimino)ethyl]-N-(4-nitrobenzylidene)aniline

Li Zhao,^a Wen-Kui Dong,^a ^* Jian-Chao Wu,^a Yin-Xia Sun ^a and Li Xu ^a

^aSchool of Chemical and Biological Engineering, Lanzhou Jiaotong University, Lanzhou 730070, People's Republic of China
^*Correspondence e-mail: dongwk@mail.lzjtu.cn

(Received 18 May 2009; accepted 24 August 2009; online 12 September 2009)

In the title compound, C₁₅H₁₃N₃O₃, the dihedral angle formed by the two benzene rings is 44.23 (2)°. The crystal structure is stabilized by aromatic π–π stacking interactions, with centroid-centroid distances of 3.825 (3) and 3.870 (4) Å between the aniline and the nitrobenzene rings of neighbouring molecules, respectively. In addition, the stacked molecules exhibit intermolecular C—H⋯N and C—H⋯O interactions.

Related literature

For background to Schiff bases, see: Lozier et al. (1975 ). For the synthesis, see: Rafiq et al. (2008 ); Duan et al. (2007 ); Dong et al. (2008 ). For related structures, see: Bomfim et al. (2005 ); Fun et al. (2008 ).

Experimental

Crystal data

C₁₅H₁₃N₃O₃
M_r = 283.28
Orthorhombic, P 2₁ 2₁ 2₁
a = 7.375 (1) Å
b = 10.770 (2) Å
c = 16.906 (2) Å
V = 1342.8 (3) Å³
Z = 4
Mo Kα radiation
μ = 0.10 mm⁻¹
T = 298 K
0.50 × 0.35 × 0.10 mm

Data collection

Bruker SMART1000 CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 1996 ) T_min = 0.952, T_max = 0.990
7656 measured reflections
1700 independent reflections
899 reflections with I > 2σ(I)
R_int = 0.068

Refinement

R[F² > 2σ(F²)] = 0.043
wR(F²) = 0.115
S = 1.03
1700 reflections
195 parameters
2 restraints
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.20 e Å⁻³
Δρ_min = −0.17 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O1—H1⋯N2ⁱ	0.95 (4)	1.97 (4)	2.887 (4)	162 (4)
C1—H1A⋯O3ⁱⁱ	0.96	2.62	3.469 (5)	148
Symmetry codes: (i) $[-x+{\script{3\over 2}}, -y+1, z+{\script{1\over 2}}]$ ; (ii) x, y, z+1.

Data collection: SMART (Siemens, 1996 ); cell refinement: SAINT (Siemens, 1996); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL.

Supporting information

Crystal structure: contains datablocks 2, I. DOI: 10.1107/S1600536809033753/lx2109sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536809033753/lx2109Isup2.hkl

checkCIF report

Comment top

It is well known that Schiff bases are one of the most popular mixed-donor ligands in the field of coordination chemistry. Schiff bases often exhibit various biological activities and in many cases were shown to have antibacterial, anticancer, anti-inflammatory and antitoxic properties (Lozier et al., 1975). Some structures of oxime compounds forming by Schiff bases reaction have been reported (Bomfim et al., 2005; Fun et al., 2008). Here we report the synthesis and crystal structure of the title compound (I), (Fig. 1).

The dihedral angle in (I) formed by the aniline and nitrobenzene rings is 44.23 (2)°. The molecular packing (Fig. 2) is stabilized by aromatic π···π interactions between the aniline and the nitrobenzene rings of neighbouring molecules, with a Cg1···Cg2ⁱⁱⁱ separation of 3.825 (3) Å and a Cg1···Cg2^iv separation of 3.870 (4) Å (Fig. 2; Cg1 and Cg2 are the centroids of the C3—C8 benzene and the C10–C15 benzene rings, respectively). Additionally, intermolecular O–H···N and C—H···O interactions in the structure were observed (Table 1 and Fig. 2).

The title compound is not chiral, but space group is p212121. This is because the title compound is rigid in the crystal, and adopts a chiral helicalx-type structure.

Related literature top

For background to Schiff bases, see: Lozier et al. (1975). For the synthesis, see: Rafiq et al. (2008); Duan et al. (2007); Dong et al. (2008). For related structures, see: Bomfim et al. (2005); Fun et al. (2008).

Experimental top

4-Aminophenylethanone oxime was prepared by 1-(4-aminophenyl)ethanone, hydroxylamine sulfate and sodium acetate (Rafiq et al., 2008; Duan et al., 2007; Dong et al., 2008). To an ethanol solution (5 ml) of 4-aminophenylethanone oxime (150.2 mg, 1.00 mmol) was added dropwise an ethanol solution (5 ml) of 4-nitrobenzaldehyde (152.5 mg, 1.01 mmol). The mixture solution was stirred at 328–333 K for 5 h. After cooling to room temperature, the precipitate was filtered off, and washed successively three times with ethanol. The product was dried in vacuo and purified by recrystallization from ethanol to yield 367.5 mg (Yield, 82.6%) of solid; m.p. 484–485 K. Pale-yellow block-like single crystals suitable for X-ray diffraction studies were obtained by slow evaporation from a solution of ethyl acetate of (I) at room temperature for about one month. Anal. Calcd. for C₁₅H₁₃N₃O₃: C, 62.6; H, 4.63; N, 14.83 Found: C, 62.1; H, 4.59; N, 14.87.

Computing details top

Data collection: SMART (Siemens, 1996); cell refinement: SAINT (Siemens, 1996); data reduction: SAINT (Siemens, 1996); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top

	Fig. 1. The molecule structure of the title compound with atom numbering. Displacement ellipsoids for non-hydrogen atoms are drawn at the 30% probability level.
	Fig. 2. π···π, O—H···N and C—H···O interactions (dotted lines) in the crystal structure of the title compound. Cg denotes the ring centroids. [Symmetry code: (i) -x + 3/2, -y + 1, z + 1/2; (ii) x, y, z + 1; (iii) x + 1/2, -y + 3/2, -z + 1; (iv) x - 1/2, -y + 3/2, -z + 1; (v) -x + 3/2, -y + 1, z - 1/2.]

4-[1-(Hydroxyimino)ethyl]-N-(4-nitrobenzylidene)aniline top

Crystal data top

C₁₅H₁₃N₃O₃	F(000) = 592
M_r = 283.28	D_x = 1.401 Mg m⁻³
Orthorhombic, P2₁2₁2₁	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ac 2ab	Cell parameters from 1209 reflections
a = 7.375 (1) Å	θ = 2.2–21.4°
b = 10.770 (2) Å	µ = 0.10 mm⁻¹
c = 16.906 (2) Å	T = 298 K
V = 1342.8 (3) Å³	Block-like, pale-yellow
Z = 4	0.50 × 0.35 × 0.10 mm

Data collection top

Bruker SMART1000 CCD area-detector diffractometer	1700 independent reflections
Radiation source: fine-focus sealed tube	899 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.068
phi and ω scans	θ_max = 27.0°, θ_min = 2.2°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	h = −9→9
T_min = 0.952, T_max = 0.990	k = −13→13
7656 measured reflections	l = −14→21

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)] = 0.043	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.115	H atoms treated by a mixture of independent and constrained refinement
S = 1.03	w = 1/[σ²(F_o²) + (0.0438P)² + 0.0834P] where P = (F_o² + 2F_c²)/3
1700 reflections	(Δ/σ)_max < 0.001
195 parameters	Δρ_max = 0.20 e Å⁻³
2 restraints	Δρ_min = −0.17 e Å⁻³

Crystal data top

C₁₅H₁₃N₃O₃	V = 1342.8 (3) Å³
M_r = 283.28	Z = 4
Orthorhombic, P2₁2₁2₁	Mo Kα radiation
a = 7.375 (1) Å	µ = 0.10 mm⁻¹
b = 10.770 (2) Å	T = 298 K
c = 16.906 (2) Å	0.50 × 0.35 × 0.10 mm

Data collection top

Bruker SMART1000 CCD area-detector diffractometer	1700 independent reflections
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	899 reflections with I > 2σ(I)
T_min = 0.952, T_max = 0.990	R_int = 0.068
7656 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.043	2 restraints
wR(F²) = 0.115	H atoms treated by a mixture of independent and constrained refinement
S = 1.03	Δρ_max = 0.20 e Å⁻³
1700 reflections	Δρ_min = −0.17 e Å⁻³
195 parameters

Special details top

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.

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 > σ(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	0.7084 (5)	0.5375 (3)	0.90756 (16)	0.0478 (9)
N2	0.6140 (4)	0.6960 (3)	0.54920 (16)	0.0389 (8)
N3	0.6281 (5)	0.8627 (4)	0.1831 (2)	0.0601 (11)
O1	0.7150 (4)	0.5267 (3)	0.99032 (15)	0.0636 (10)
H1	0.784 (6)	0.454 (4)	0.999 (3)	0.100 (18)*
O2	0.6733 (5)	0.9635 (3)	0.15589 (17)	0.0830 (11)
O3	0.5894 (6)	0.7723 (3)	0.14311 (17)	0.0939 (13)
C1	0.5534 (7)	0.7318 (4)	0.9402 (2)	0.0755 (15)
H1A	0.5821	0.7090	0.9936	0.113*
H1B	0.4241	0.7352	0.9339	0.113*
H1C	0.6046	0.8117	0.9286	0.113*
C2	0.6304 (5)	0.6371 (3)	0.8846 (2)	0.0384 (9)
C3	0.6214 (5)	0.6542 (3)	0.79802 (19)	0.0319 (9)
C4	0.5531 (5)	0.7611 (3)	0.76460 (19)	0.0394 (10)
H4	0.5084	0.8235	0.7972	0.047*
C5	0.5498 (5)	0.7776 (3)	0.6832 (2)	0.0391 (10)
H5	0.5041	0.8510	0.6621	0.047*
C6	0.6133 (5)	0.6869 (3)	0.63323 (19)	0.0328 (9)
C7	0.6787 (5)	0.5777 (3)	0.6663 (2)	0.0381 (10)
H7	0.7201	0.5145	0.6334	0.046*
C8	0.6832 (5)	0.5618 (3)	0.7469 (2)	0.0377 (9)
H8	0.7283	0.4880	0.7677	0.045*
C9	0.6249 (5)	0.8019 (3)	0.5170 (2)	0.0402 (10)
H9	0.6364	0.8719	0.5489	0.048*
C10	0.6198 (5)	0.8171 (3)	0.43071 (19)	0.0375 (10)
C11	0.6747 (5)	0.9298 (3)	0.3977 (2)	0.0454 (11)
H11	0.7098	0.9948	0.4305	0.055*
C12	0.6773 (5)	0.9453 (4)	0.3167 (2)	0.0466 (11)
H12	0.7156	1.0198	0.2944	0.056*
C13	0.6223 (5)	0.8484 (4)	0.2699 (2)	0.0407 (10)
C14	0.5622 (5)	0.7378 (3)	0.3007 (2)	0.0436 (11)
H14	0.5223	0.6743	0.2678	0.052*
C15	0.5627 (5)	0.7232 (3)	0.3816 (2)	0.0405 (10)
H15	0.5237	0.6485	0.4034	0.049*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
N1	0.069 (3)	0.0466 (19)	0.0279 (16)	0.0068 (19)	−0.0017 (17)	0.0065 (15)
N2	0.043 (2)	0.0377 (17)	0.0363 (18)	0.0016 (17)	0.0005 (16)	0.0021 (14)
N3	0.060 (3)	0.080 (3)	0.040 (2)	0.017 (3)	0.003 (2)	0.013 (2)
O1	0.097 (3)	0.0590 (19)	0.0348 (15)	0.014 (2)	−0.0051 (16)	0.0064 (14)
O2	0.100 (3)	0.094 (2)	0.0551 (19)	0.010 (2)	0.0065 (19)	0.0338 (19)
O3	0.139 (4)	0.100 (3)	0.0422 (19)	0.005 (3)	−0.002 (2)	−0.0081 (19)
C1	0.111 (4)	0.072 (3)	0.044 (2)	0.031 (3)	−0.003 (3)	−0.011 (2)
C2	0.043 (3)	0.034 (2)	0.038 (2)	−0.007 (2)	0.0012 (18)	−0.0009 (17)
C3	0.030 (2)	0.034 (2)	0.032 (2)	−0.0030 (19)	−0.0013 (17)	0.0024 (16)
C4	0.042 (3)	0.038 (2)	0.038 (2)	0.002 (2)	0.0005 (18)	−0.0033 (18)
C5	0.042 (3)	0.033 (2)	0.043 (2)	0.0047 (19)	−0.0014 (18)	0.0071 (17)
C6	0.034 (2)	0.037 (2)	0.027 (2)	−0.0009 (19)	0.0004 (17)	0.0015 (15)
C7	0.042 (3)	0.035 (2)	0.037 (2)	−0.001 (2)	0.0061 (19)	−0.0006 (17)
C8	0.043 (3)	0.0325 (19)	0.037 (2)	0.002 (2)	−0.0015 (18)	0.0024 (17)
C9	0.044 (3)	0.041 (2)	0.035 (2)	0.000 (2)	−0.0051 (19)	−0.0031 (17)
C10	0.038 (3)	0.039 (2)	0.035 (2)	0.0029 (19)	0.0034 (19)	−0.0022 (17)
C11	0.045 (3)	0.042 (2)	0.049 (2)	0.002 (2)	−0.005 (2)	0.0022 (18)
C12	0.048 (3)	0.042 (2)	0.050 (3)	0.004 (2)	0.000 (2)	0.0166 (19)
C13	0.039 (3)	0.051 (2)	0.032 (2)	0.013 (2)	0.0026 (18)	0.0079 (18)
C14	0.043 (3)	0.044 (2)	0.044 (2)	0.008 (2)	−0.0051 (18)	−0.0009 (19)
C15	0.039 (3)	0.042 (2)	0.041 (2)	0.003 (2)	0.0038 (18)	0.0064 (18)

Geometric parameters (Å, º) top

N1—C2	1.278 (4)	C5—H5	0.9300
N1—O1	1.405 (4)	C6—C7	1.388 (4)
N2—C9	1.266 (4)	C7—C8	1.375 (5)
N2—C6	1.424 (4)	C7—H7	0.9300
N3—O3	1.219 (4)	C8—H8	0.9300
N3—O2	1.225 (4)	C9—C10	1.469 (5)
N3—C13	1.476 (5)	C9—H9	0.9300
O1—H1	0.95 (4)	C10—C15	1.375 (5)
C1—C2	1.498 (5)	C10—C11	1.396 (5)
C1—H1A	0.9600	C11—C12	1.378 (5)
C1—H1B	0.9600	C11—H11	0.9300
C1—H1C	0.9600	C12—C13	1.371 (5)
C2—C3	1.477 (4)	C12—H12	0.9300
C3—C4	1.378 (4)	C13—C14	1.374 (5)
C3—C8	1.395 (4)	C14—C15	1.376 (4)
C4—C5	1.388 (4)	C14—H14	0.9300
C4—H4	0.9300	C15—H15	0.9300
C5—C6	1.374 (5)

C2—N1—O1	112.8 (3)	C8—C7—C6	120.9 (3)
C9—N2—C6	119.4 (3)	C8—C7—H7	119.6
O3—N3—O2	124.2 (4)	C6—C7—H7	119.6
O3—N3—C13	117.5 (4)	C7—C8—C3	121.1 (3)
O2—N3—C13	118.3 (4)	C7—C8—H8	119.4
N1—O1—H1	104 (3)	C3—C8—H8	119.4
C2—C1—H1A	109.5	N2—C9—C10	121.7 (3)
C2—C1—H1B	109.5	N2—C9—H9	119.1
H1A—C1—H1B	109.5	C10—C9—H9	119.1
C2—C1—H1C	109.5	C15—C10—C11	119.1 (3)
H1A—C1—H1C	109.5	C15—C10—C9	121.7 (3)
H1B—C1—H1C	109.5	C11—C10—C9	119.2 (3)
N1—C2—C3	115.2 (3)	C12—C11—C10	120.4 (4)
N1—C2—C1	123.5 (3)	C12—C11—H11	119.8
C3—C2—C1	121.3 (3)	C10—C11—H11	119.8
C4—C3—C8	117.5 (3)	C13—C12—C11	118.5 (4)
C4—C3—C2	121.8 (3)	C13—C12—H12	120.8
C8—C3—C2	120.7 (3)	C11—C12—H12	120.8
C3—C4—C5	121.3 (3)	C12—C13—C14	122.4 (3)
C3—C4—H4	119.3	C12—C13—N3	119.1 (4)
C5—C4—H4	119.3	C14—C13—N3	118.5 (4)
C6—C5—C4	120.8 (3)	C13—C14—C15	118.4 (4)
C6—C5—H5	119.6	C13—C14—H14	120.8
C4—C5—H5	119.6	C15—C14—H14	120.8
C5—C6—C7	118.3 (3)	C10—C15—C14	121.1 (4)
C5—C6—N2	124.4 (3)	C10—C15—H15	119.5
C7—C6—N2	117.3 (3)	C14—C15—H15	119.5

O1—N1—C2—C3	179.3 (3)	C6—N2—C9—C10	−177.8 (3)
O1—N1—C2—C1	−0.3 (6)	N2—C9—C10—C15	15.0 (6)
N1—C2—C3—C4	−175.2 (3)	N2—C9—C10—C11	−164.9 (4)
C1—C2—C3—C4	4.4 (6)	C15—C10—C11—C12	−2.1 (6)
N1—C2—C3—C8	4.4 (5)	C9—C10—C11—C12	177.8 (3)
C1—C2—C3—C8	−175.9 (4)	C10—C11—C12—C13	1.0 (6)
C8—C3—C4—C5	−1.5 (5)	C11—C12—C13—C14	1.0 (6)
C2—C3—C4—C5	178.2 (4)	C11—C12—C13—N3	−178.7 (4)
C3—C4—C5—C6	0.6 (6)	O3—N3—C13—C12	175.4 (4)
C4—C5—C6—C7	0.8 (6)	O2—N3—C13—C12	−3.7 (6)
C4—C5—C6—N2	179.7 (3)	O3—N3—C13—C14	−4.3 (6)
C9—N2—C6—C5	28.3 (6)	O2—N3—C13—C14	176.5 (4)
C9—N2—C6—C7	−152.8 (4)	C12—C13—C14—C15	−1.9 (6)
C5—C6—C7—C8	−1.3 (6)	N3—C13—C14—C15	177.8 (4)
N2—C6—C7—C8	179.8 (3)	C11—C10—C15—C14	1.3 (6)
C6—C7—C8—C3	0.4 (6)	C9—C10—C15—C14	−178.6 (3)
C4—C3—C8—C7	1.0 (6)	C13—C14—C15—C10	0.7 (6)
C2—C3—C8—C7	−178.7 (3)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1···N2ⁱ	0.95 (4)	1.97 (4)	2.887 (4)	162 (4)
C1—H1A···O3ⁱⁱ	0.96	2.62	3.469 (5)	148

Symmetry codes: (i) −x+3/2, −y+1, z+1/2; (ii) x, y, z+1.

Experimental details

Crystal data
Chemical formula	C₁₅H₁₃N₃O₃
M_r	283.28
Crystal system, space group	Orthorhombic, P2₁2₁2₁
Temperature (K)	298
a, b, c (Å)	7.375 (1), 10.770 (2), 16.906 (2)
V (Å³)	1342.8 (3)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.10
Crystal size (mm)	0.50 × 0.35 × 0.10

Data collection
Diffractometer	Bruker SMART1000 CCD area-detector diffractometer
Absorption correction	Multi-scan (SADABS; Sheldrick, 1996)
T_min, T_max	0.952, 0.990
No. of measured, independent and observed [I > 2σ(I)] reflections	7656, 1700, 899
R_int	0.068
(sin θ/λ)_max (Å⁻¹)	0.639

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.043, 0.115, 1.03
No. of reflections	1700
No. of parameters	195
No. of restraints	2
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.20, −0.17

Computer programs: SMART (Siemens, 1996), SAINT (Siemens, 1996), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1···N2ⁱ	0.95 (4)	1.97 (4)	2.887 (4)	162 (4)
C1—H1A···O3ⁱⁱ	0.96	2.62	3.469 (5)	147.9

Symmetry codes: (i) −x+3/2, −y+1, z+1/2; (ii) x, y, z+1.

Acknowledgements

The authors acknowledge financial support from the Foundation of the Education Department of Gansu Province (No. 20873).

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