1,3-Bis[(4-nitro­benzyl­idene)amino­oxy]propane

Dong, W.-K.; Sun, Y.-X.; Tong, J.-F.; Zhao, H.-H.; Wang, L.

doi:10.1107/S1600536809031316

organic compounds

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ISSN: 2056-9890

Volume 65| Part 9| September 2009| Pages o2141-o2142

doi:10.1107/S1600536809031316

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1,3-Bis[(4-nitrobenzylidene)aminooxy]propane

Wen-Kui Dong,^a ^* Yin-Xia Sun,^a Jun-Feng Tong,^a Hai-Hong Zhao ^a and Li Wang ^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 13 July 2009; accepted 8 August 2009; online 12 August 2009)

The complete molecule of title compound, C₁₇H₁₆N₄O₆, is generated by a crystallographic twofold axis. Within the molecule, the two benzene units are approximately perpendicular, making a dihedral angle of 85.91 (4)°. In the crystal, molecules are linked into a three-dimensional network by C—H⋯O hydrogen bonds and short O⋯O and N⋯O interactions, with distances of 2.998 (2) and 2.968 (3) Å, respectively.

Related literature

For general background to Schiff base complexes and their applications, see: Niederhoffer et al. (1984 ); Zhang et al. (1990 ); Tisato et al. (1994 ); Lacroix (2001 ); Sundari et al. (1997 ); Koehler et al. (1964 ); Cordes & Jencks (1962 ); Akine et al. (2006 ). For related structures, see: Fun et al. (2008a ,b ); Kia et al. (2009 ); Shi et al. (2007 ); Ren et al. (2008 ); Ding et al. (2009 ); Dong et al. (2008a ). For a related Schiff base bisoxime compound synthesized using a similar route, see: Dong et al. (2008b ).

Experimental

Crystal data

C₁₇H₁₆N₄O₆
M_r = 372.34
Monoclinic, C 2
a = 29.005 (3) Å
b = 4.7878 (5) Å
c = 6.3579 (7) Å
β = 99.144 (1)°
V = 871.71 (16) Å³
Z = 2
Mo Kα radiation
μ = 0.11 mm⁻¹
T = 298 K
0.45 × 0.17 × 0.06 mm

Data collection

Siemens SMART 1000 CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 1996 ) T_min = 0.952, T_max = 0.993
2321 measured reflections
872 independent reflections
675 reflections with I > 2σ(I)
R_int = 0.049

Refinement

R[F² > 2σ(F²)] = 0.039
wR(F²) = 0.094
S = 0.96
872 reflections
123 parameters
1 restraint
H-atom parameters constrained
Δρ_max = 0.13 e Å⁻³
Δρ_min = −0.19 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C3—H3⋯O3ⁱ	0.93	2.40	3.206 (4)	145
C9—H9⋯O3ⁱ	0.93	2.63	3.395 (4)	139
C9—H9⋯O2ⁱⁱ	0.93	2.71	3.374 (4)	129
Symmetry codes: (i) x, y-1, z+1; (ii) $[-x+{\script{3\over 2}}, y-{\script{1\over 2}}, -z+1]$ .

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 global, I. DOI: 10.1107/S1600536809031316/fl2256sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536809031316/fl2256Isup2.hkl

checkCIF report

Comment top

Schiff bases are among the most prevalent mixed-donor ligands in the field of coordination chemistry in which there has been growing interest, mainly because of their wide application in areas such as biochemistry (Niederhoffer et al., 1984), catalysis (Zhang et al., 1990), medical imaging (Tisato et al., 1994), optical materials (Lacroix, 2001) and thin films (Sundari et al., 1997). Although most Schiff bases are stable in both solution and the solid state, C=N bonds often suffer exchange reactions (Koehler et al., 1964) as well as hydrolysis (Cordes & Jencks, 1962). Rate constants of oxime formation are smaller than those of imine formation and the equilibrium constants are larger by several orders (Akine et al., 2006). Hence, the title compound should be stable enough to resist the metathesis of the C=N bonds. Many bisdentate Schiff base compounds have been structurally characterized (Fun et al., 2008a; Fun et al., 2008b; Kia et al., 2009), but only a relatively small number of bisoxime compounds have had their X-ray structures reported (Shi et al., 2007; Ren et al., 2008). As an extension of our work (Ding et al., 2009; Dong et al., 2008a) on the structural characterization of bisoxime compounds, the title compound, is reported here (Fig. 1).

In the title compound all bond lengths are in normal ranges. The molecule sits on a crystallographic twofold passing through the central CH₂ group (symmetry code: -x, y, -z) such that there is 1/2 molecule per asymmetric unit. Within the molecule, the dihedral angle between the plane of oxime functional group and benzene ring is about 0.54 (3)° for O1—N1—C3 and the C4—C9 ring, and the two benzene rings are approximately perpendicular with a dihedral angle of 85.91 (4)°. In the crystal intermolecular C—H···O hydrogen bonds link the molecules into an infinite three-dimensional supramolecular network. The molecules are held together by intermolecular hydrogen bonds (Table 1) to form infinite zigzag chains along the a axis and wave-like layers parallel to the ac plane (Fig. 2). In addition, the interesting features of the crystal structure are short intermolecular O···O and N···O interactions that form infinite helical chains along the b axis as depicted in Fig. 3. The O···O and N···O distances of 2.998 (2) and 2.968 (3) Å, respectively, are significantly shorter than the sum of the van der Waals radii of the relevant atoms. Thus, the zigzag and helical chains form a three-dimensional supramolecular structure through the crosslinked hydrogen-bonded and short intermolecular O···O and N···O interactions (Fig. 4).

Related literature top

For general background to Schiff base complexes and their applications, see: Niederhoffer et al. (1984); Zhang et al. (1990); Tisato et al. (1994); Lacroix (2001); Sundari et al. (1997); Koehler et al. (1964); Cordes & Jencks (1962); Akine et al. (2006). For related structures, see: Fun et al. (2008a,b); Kia et al. (2009); Shi et al. (2007); Ren et al. (2008); Ding et al. (2009); Dong et al. (2008a). For a related Schiff base bisoxime compound synthesized using a similar route, see: Dong et al. (2008b).

Experimental top

The title compound was synthesized according to an analogous method reported earlier (Dong et al., 2008b). To an ethanol solution (2 ml) of p-nitrobenzene (186.6 mg, 1.235 mmol) was added dropwise an ethanol solution (3 ml) of 1,3-bis(aminooxy)propane (51.3 mg, 0.473 mmol). The mixture was stirred at 328 K for 3 h. After cooling to room temperature, the precipitate was filtered off, and washed successively with ethanol and n-hexane, respectively. The product was dried in vacuo and purified by recrystallization from ethanol to yield 127.8 mg of (1); Yield, 71.8%. m. p. 427–429 K. Anal. Calcd. for C₁₇H₁₆N₄O₆: C, 54.84; H, 4.33; N, 15.05; Found: C, 55.06; H, 4.29; N, 15.04.

Colorless needle-like single crystals suitable for X-ray diffraction studies were obtained after about two weeks by slow evaporation from a chloroform-N,N-dimethylformamide of mixed solution of the title compound at room temperature.

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 molecular structure of the title compound with atom numbering scheme. Displacement ellipsoids for non-hydrogen atoms are drawn at the 30% probability level.
	Fig. 2. The intermolecular hydrogen bonds and short O···O and N···O interactions (dashed lines), showing zigzag chains along a axis and wave-like layers parallel to the ac plane.
	Fig. 3. The infinite helical chains along b axis linked by short O···O and N···O interactions, other atoms are omitted for clarity.
	Fig. 4. Part of the three-dimensional supramolecular network structure of the title compound.

1,3-Bis[(4-nitrobenzylidene)aminooxy]propane top

Crystal data top

C₁₇H₁₆N₄O₆	F(000) = 388
M_r = 372.34	D_x = 1.419 Mg m⁻³
Monoclinic, C2	Melting point = 427–429 K
Hall symbol: C 2y	Mo Kα radiation, λ = 0.71073 Å
a = 29.005 (3) Å	Cell parameters from 773 reflections
b = 4.7878 (5) Å	θ = 2.9–25.3°
c = 6.3579 (7) Å	µ = 0.11 mm⁻¹
β = 99.144 (1)°	T = 298 K
V = 871.71 (16) Å³	Needle-like, colorless
Z = 2	0.45 × 0.17 × 0.06 mm

Data collection top

Siemens SMART 1000 CCD area-detector diffractometer	872 independent reflections
Radiation source: fine-focus sealed tube	675 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.049
ϕ and ω scans	θ_max = 25.0°, θ_min = 1.4°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	h = −23→34
T_min = 0.952, T_max = 0.993	k = −5→5
2321 measured reflections	l = −7→7

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)] = 0.039	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.094	H-atom parameters constrained
S = 0.96	w = 1/[σ²(F_o²) + (0.0524P)²] where P = (F_o² + 2F_c²)/3
872 reflections	(Δ/σ)_max < 0.001
123 parameters	Δρ_max = 0.13 e Å⁻³
1 restraint	Δρ_min = −0.19 e Å⁻³

Crystal data top

C₁₇H₁₆N₄O₆	V = 871.71 (16) Å³
M_r = 372.34	Z = 2
Monoclinic, C2	Mo Kα radiation
a = 29.005 (3) Å	µ = 0.11 mm⁻¹
b = 4.7878 (5) Å	T = 298 K
c = 6.3579 (7) Å	0.45 × 0.17 × 0.06 mm
β = 99.144 (1)°

Data collection top

Siemens SMART 1000 CCD area-detector diffractometer	872 independent reflections
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	675 reflections with I > 2σ(I)
T_min = 0.952, T_max = 0.993	R_int = 0.049
2321 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.039	1 restraint
wR(F²) = 0.094	H-atom parameters constrained
S = 0.96	Δρ_max = 0.13 e Å⁻³
872 reflections	Δρ_min = −0.19 e Å⁻³
123 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	Occ. (<1)
N1	0.93031 (9)	0.2933 (7)	0.6567 (4)	0.0497 (7)
N2	0.79744 (9)	1.2194 (6)	0.1169 (4)	0.0479 (7)
O1	0.94454 (7)	0.1141 (6)	0.8289 (3)	0.0560 (7)
O2	0.76377 (8)	1.3375 (6)	0.1705 (3)	0.0643 (7)
O3	0.81103 (8)	1.2669 (6)	−0.0530 (3)	0.0656 (8)
C1	0.98599 (10)	−0.0342 (8)	0.8012 (4)	0.0508 (9)
H1A	1.0106	0.0956	0.7815	0.061*
H1B	0.9799	−0.1551	0.6775	0.061*
C2	1.0000	−0.2040 (12)	1.0000	0.0511 (12)
H2A	0.9741	−0.3236	1.0203	0.061*	0.50
H2B	1.0259	−0.3236	0.9797	0.061*	0.50
C3	0.89337 (11)	0.4213 (8)	0.6853 (5)	0.0486 (9)
H3	0.8809	0.3840	0.8082	0.058*
C4	0.86975 (10)	0.6240 (8)	0.5337 (4)	0.0418 (8)
C5	0.88617 (10)	0.6955 (7)	0.3454 (4)	0.0501 (9)
H5	0.9130	0.6115	0.3120	0.060*
C6	0.86237 (10)	0.8918 (7)	0.2086 (5)	0.0481 (9)
H6	0.8733	0.9422	0.0841	0.058*
C7	0.82254 (10)	1.0105 (7)	0.2594 (4)	0.0405 (7)
C8	0.80565 (10)	0.9443 (8)	0.4438 (4)	0.0470 (9)
H8	0.7787	1.0280	0.4756	0.056*
C9	0.82958 (10)	0.7517 (8)	0.5798 (4)	0.0473 (8)
H9	0.8186	0.7061	0.7053	0.057*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
N1	0.0561 (17)	0.0467 (17)	0.0439 (14)	−0.0031 (16)	0.0009 (12)	0.0075 (15)
N2	0.0530 (16)	0.0421 (18)	0.0486 (14)	−0.0031 (15)	0.0076 (13)	0.0048 (14)
O1	0.0543 (14)	0.0622 (16)	0.0514 (12)	0.0090 (13)	0.0083 (10)	0.0130 (13)
O2	0.0691 (15)	0.0610 (18)	0.0650 (14)	0.0177 (15)	0.0178 (12)	0.0114 (14)
O3	0.0766 (15)	0.0688 (19)	0.0547 (12)	0.0025 (15)	0.0208 (11)	0.0196 (15)
C1	0.0476 (17)	0.047 (2)	0.0561 (19)	−0.0001 (18)	0.0044 (15)	−0.0014 (17)
C2	0.049 (3)	0.044 (3)	0.057 (3)	0.000	−0.001 (2)	0.000
C3	0.0467 (17)	0.051 (2)	0.0488 (18)	−0.002 (2)	0.0108 (15)	0.0082 (18)
C4	0.0441 (17)	0.0393 (19)	0.0408 (15)	−0.0048 (16)	0.0034 (14)	0.0022 (16)
C5	0.0471 (18)	0.056 (3)	0.0495 (17)	0.0035 (19)	0.0136 (15)	0.0007 (18)
C6	0.0535 (19)	0.052 (2)	0.0405 (16)	−0.0020 (19)	0.0125 (14)	0.0062 (16)
C7	0.0457 (16)	0.0351 (18)	0.0395 (15)	−0.0039 (15)	0.0032 (13)	0.0016 (14)
C8	0.0469 (18)	0.048 (2)	0.0486 (18)	0.0014 (18)	0.0165 (15)	0.0034 (17)
C9	0.0480 (17)	0.051 (2)	0.0448 (16)	0.0022 (18)	0.0139 (13)	0.0090 (17)

Geometric parameters (Å, º) top

N1—C3	1.273 (4)	C3—C4	1.459 (4)
N1—O1	1.401 (3)	C3—H3	0.9300
N2—O2	1.223 (3)	C4—C9	1.388 (4)
N2—O3	1.229 (3)	C4—C5	1.399 (4)
N2—C7	1.464 (4)	C5—C6	1.387 (4)
O1—C1	1.431 (3)	C5—H5	0.9300
C1—C2	1.503 (5)	C6—C7	1.371 (4)
C1—H1A	0.9700	C6—H6	0.9300
C1—H1B	0.9700	C7—C8	1.378 (4)
C2—C1ⁱ	1.503 (5)	C8—C9	1.374 (5)
C2—H2A	0.9700	C8—H8	0.9300
C2—H2B	0.9700	C9—H9	0.9300

C3—N1—O1	109.5 (2)	C4—C3—H3	118.5
O2—N2—O3	122.8 (3)	C9—C4—C5	119.0 (3)
O2—N2—C7	119.0 (2)	C9—C4—C3	118.4 (3)
O3—N2—C7	118.2 (3)	C5—C4—C3	122.7 (3)
N1—O1—C1	110.9 (2)	C6—C5—C4	119.9 (3)
O1—C1—C2	106.5 (2)	C6—C5—H5	120.0
O1—C1—H1A	110.4	C4—C5—H5	120.0
C2—C1—H1A	110.4	C7—C6—C5	119.2 (3)
O1—C1—H1B	110.4	C7—C6—H6	120.4
C2—C1—H1B	110.4	C5—C6—H6	120.4
H1A—C1—H1B	108.6	C6—C7—C8	122.1 (3)
C1ⁱ—C2—C1	114.5 (5)	C6—C7—N2	119.5 (3)
C1ⁱ—C2—H2A	108.6	C8—C7—N2	118.4 (3)
C1—C2—H2A	108.6	C9—C8—C7	118.5 (3)
C1ⁱ—C2—H2B	108.6	C9—C8—H8	120.7
C1—C2—H2B	108.6	C7—C8—H8	120.7
H2A—C2—H2B	107.6	C8—C9—C4	121.3 (3)
N1—C3—C4	122.9 (3)	C8—C9—H9	119.3
N1—C3—H3	118.5	C4—C9—H9	119.3

C3—N1—O1—C1	179.8 (3)	C5—C6—C7—N2	179.5 (3)
N1—O1—C1—C2	176.2 (3)	O2—N2—C7—C6	−175.2 (3)
O1—C1—C2—C1ⁱ	−64.9 (2)	O3—N2—C7—C6	5.4 (4)
O1—N1—C3—C4	179.9 (3)	O2—N2—C7—C8	3.4 (4)
N1—C3—C4—C9	179.9 (3)	O3—N2—C7—C8	−176.0 (3)
N1—C3—C4—C5	−0.6 (5)	C6—C7—C8—C9	−0.3 (5)
C9—C4—C5—C6	0.1 (5)	N2—C7—C8—C9	−178.9 (3)
C3—C4—C5—C6	−179.4 (3)	C7—C8—C9—C4	−0.4 (5)
C4—C5—C6—C7	−0.9 (5)	C5—C4—C9—C8	0.5 (5)
C5—C6—C7—C8	1.0 (5)	C3—C4—C9—C8	−179.9 (3)

Symmetry code: (i) −x+2, y, −z+2.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C3—H3···O3ⁱⁱ	0.93	2.40	3.206 (4)	145
C9—H9···O3ⁱⁱ	0.93	2.63	3.395 (4)	139
C9—H9···O2ⁱⁱⁱ	0.93	2.71	3.374 (4)	129

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

Experimental details

Crystal data
Chemical formula	C₁₇H₁₆N₄O₆
M_r	372.34
Crystal system, space group	Monoclinic, C2
Temperature (K)	298
a, b, c (Å)	29.005 (3), 4.7878 (5), 6.3579 (7)
β (°)	99.144 (1)
V (Å³)	871.71 (16)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	0.11
Crystal size (mm)	0.45 × 0.17 × 0.06

Data collection
Diffractometer	Siemens SMART 1000 CCD area-detector diffractometer
Absorption correction	Multi-scan (SADABS; Sheldrick, 1996)
T_min, T_max	0.952, 0.993
No. of measured, independent and observed [I > 2σ(I)] reflections	2321, 872, 675
R_int	0.049
(sin θ/λ)_max (Å⁻¹)	0.595

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.039, 0.094, 0.96
No. of reflections	872
No. of parameters	123
No. of restraints	1
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.13, −0.19

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
C3—H3···O3ⁱ	0.93	2.40	3.206 (4)	144.9
C9—H9···O3ⁱ	0.93	2.63	3.395 (4)	139.4
C9—H9···O2ⁱⁱ	0.93	2.71	3.374 (4)	129.3

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

Acknowledgements

This work was supported by the Foundation of the Education Department of Gansu Province (No. 0904-11) and the `Jing Lan' Talent Engineering Funds of Lanzhou Jiaotong University, which are gratefully acknowledged.

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