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organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 67| Part 9| September 2011| Page o2319
doi:10.1107/S1600536811032028

2-{(E)-[(4-Methyl­phen­yl)imino]­meth­yl}-4-nitro­phenol–2-{(E)-[(4-methyl­phen­yl)iminio]meth­yl}-4-nitro­phenolate (0.60/0.40)

M. Nawaz Tahir,a* Hazoor Ahmad Shadb and Riaz H. Tariqc

aDepartment of Physics, University of Sargodha, Sargodha, Pakistan, bDepartment of Chemistry, Govt. M. D. College, Toba Tek Singh, Punjab, Pakistan, and cInstitute of Chemical and Pharmaceutical Sciences, The University of Faisalabad, Faisalabad, Pakistan
*Correspondence e-mail: dmntahir_uos@yahoo.com

(Received 6 August 2011; accepted 8 August 2011; online 11 August 2011)

The crystal of the title compound, 0.6C14H12N2O3·0.4C14H12N2O3, contains a mixture of its neutral (OH containing) and zwitterionic (NH containing) forms, in a 0.60 (4):0.40 (4) ratio. The former generates an S(6) loop via an intra­molecular O—H⋯N hydrogen bond and the latter generates an S(6) loop via an N—H⋯O hydro­gren bond. The aromatic rings are oriented at a dihedral angle of 42.52 (10)°. In the crystal, C—H⋯π inter­actions occur and aromatic π–π stacking inter­actions [centroid–centroid separations = 3.7106 (12) and 3.9177 (13) Å] consolidate the packing.

Related literature

For related structures, see: Hijji et al. (2009[Hijji, Y. M., Barare, B., Butcher, R. J. & Jasinski, J. P. (2009). Acta Cryst. E65, o291-o292.]); Kılıç et al. (2009[Kılıç, I., Ağar, E., Erşahin, F. & Işık, Ş. (2009). Acta Cryst. E65, o737.]). For graph-set notation, see: Bernstein et al. (1995[Bernstein, J., Davis, R. E., Shimoni, L. & Chang, N.-L. (1995). Angew. Chem. Int. Ed. Engl. 34, 1555-1573.]).

[Scheme 1]

Experimental

Crystal data

  • 0.6C14H12N2O3·0.4C14H12N2O3

  • Mr = 256.26

  • Monoclinic, P 21 /c

  • a = 14.0623 (6) Å

  • b = 14.1723 (8) Å

  • c = 6.2357 (3) Å

  • β = 95.400 (2)°

  • V = 1237.23 (11) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.10 mm−1

  • T = 296 K

  • 0.25 × 0.22 × 0.20 mm
Data collection

  • Bruker Kappa APEXII CCD diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2005[Bruker (2005). SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.976, Tmax = 0.985

  • 9733 measured reflections

  • 2238 independent reflections

  • 1395 reflections with I > 2σ(I)

  • Rint = 0.041
Refinement

  • R[F2 > 2σ(F2)] = 0.049

  • wR(F2) = 0.133

  • S = 1.03

  • 2238 reflections

  • 181 parameters

  • H atoms treated by a mixture of independent and constrained refinement

  • Δρmax = 0.20 e Å−3

  • Δρmin = −0.18 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

Cg1 and Cg2 are the centroids of the C1—C6 and C9—C14 rings, respectively.
D—H⋯A D—H H⋯A D⋯A D—H⋯A
O1—H1⋯N1 0.80 (6) 1.86 (6) 2.566 (3) 147 (6)
N1—H1A⋯O1 0.97 (8) 1.71 (7) 2.566 (3) 146 (6)
C5—H5⋯Cg1i 0.93 2.84 3.515 (2) 130
C11—H11⋯Cg2ii 0.93 2.82 3.490 (2) 130
Symmetry codes: (i) [x, -y+{\script{3\over 2}}, z+{\script{1\over 2}}]; (ii) [x, -y+{\script{3\over 2}}, z-{\script{1\over 2}}].

Data collection: APEX2 (Bruker, 2009[Bruker (2009). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2009[Bruker (2009). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT (Bruker, 2009[Bruker (2009). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997[Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565.]) and PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]); software used to prepare material for publication: WinGX (Farrugia, 1999[Farrugia, L. J. (1999). J. Appl. Cryst. 32, 837-838.]) and PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]).

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536811032028/hb6352sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536811032028/hb6352Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536811032028/hb6352Isup3.cml

checkCIF report


Comment top

The crystal structures of 2-((4-methoxyphenyl)iminomethyl)-4-nitrophenol (Kılıç et al., 2009) and 2-(((E)-(2-hydroxy-5-nitrophenyl) methylidene)ammonio)-4-nitrophenolate (Hijji et al., 2009) have been published which are related to the title compound (I), (Fig. 1). The title compound consists of two isomers with 0.60:0.40 ratio.

In (I), the 4-methylanilinic group A (C1—C7/N1) and the 2-hydroxy-5-nitrobenzaldehyde group B (C8—C14/N2/O1/O2/O3) are almost planar with r.m.s. deviations of 0.0283 and 0.0222 Å, respectively. The dihedral angle between A/B is 41.86 (4)°. There exist intramolecular hydrogen bonds of O—H···N and N—H···O type completing S(6) (Bernstein et al., 1995) ring motifs (Table 1, Fig. 2). In the crystal, there exist π–π interaction between the centroids of the benzene rings of 4-methyaniline with a separation of 3.9177 (13) Å and a slippage of 1.333 Å. Similarly, π–π interaction between the centroids of the benzene rings of 2-hydroxy-5-nitrobenzaldehyde also exist with a separation of 3.7106 (12) Å and a slippage of 1.452 Å. In consolidating the crystal structure, C—H···π bonds (Table 1) also play role.

Related literature top

For related structures, see: Hijji et al. (2009); Kılıç et al. (2009). For graph-set notation, see: Bernstein et al. (1995).

Experimental top

Equimolar quantities of 2-hydroxy-5-nitrobenzaldehyde and and 4-methylaniline were refluxed in ethanol for 30 min resulting in a yellow solution. The solution was kept at room temperature which affoarded yellow prisms of (I) after three days.

Refinement top

The coordinates of hydrogen atoms of O—H and N—H were refined. The occupancy factor of both H-atoms was refined and therefore, the two isomers are of 0.60:0.40 ratio. The H-atoms were positioned geometrically (C–H = 0.93 Å) and refined as riding with Uiso(H) = xUeq(C, N, O), where x = 1.2 for all H-atoms.

Computing details top

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997) and PLATON (Spek, 2009); software used to prepare material for publication: WinGX (Farrugia, 1999) and PLATON (Spek, 2009).

Figures top
[Figure 1] Fig. 1. View of the title compound with displacement ellipsoids drawn at the 50% probability level. The dotted line represents the miniority H-atom.
[Figure 2] Fig. 2. Overlapped intramolecular hydrogen bonds forming two S(6) ring motif.
2-{(E)-[(4-Methylphenyl)imino]methyl}-4-nitrophenol– 2-{(E)-[(4-methylphenyl)iminio]methyl}-4-nitrophenolate (0.60/0.40) top
Crystal data top
0.6C14H12N2O3·0.4C14H12N2O3F(000) = 536
Mr = 256.26Dx = 1.376 Mg m−3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 1395 reflections
a = 14.0623 (6) Åθ = 2.0–25.3°
b = 14.1723 (8) ŵ = 0.10 mm−1
c = 6.2357 (3) ÅT = 296 K
β = 95.400 (2)°Prism, yellow
V = 1237.23 (11) Å30.25 × 0.22 × 0.20 mm
Z = 4
Data collection top
Bruker Kappa APEXII CCD
diffractometer		2238 independent reflections
Radiation source: fine-focus sealed tube1395 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.041
Detector resolution: 8.10 pixels mm-1θmax = 25.3°, θmin = 2.0°
ω scansh = −16→16
Absorption correction: multi-scan
(SADABS; Bruker, 2005)		k = −17→17
Tmin = 0.976, Tmax = 0.985l = −7→7
9733 measured reflections
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)] = 0.049H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.133 w = 1/[σ2(Fo2) + (0.0558P)2 + 0.2667P]
where P = (Fo2 + 2Fc2)/3
S = 1.03(Δ/σ)max < 0.001
2238 reflectionsΔρmax = 0.20 e Å−3
181 parametersΔρmin = −0.18 e Å−3
0 restraintsExtinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.0052 (14)
Crystal data top
0.6C14H12N2O3·0.4C14H12N2O3V = 1237.23 (11) Å3
Mr = 256.26Z = 4
Monoclinic, P21/cMo Kα radiation
a = 14.0623 (6) ŵ = 0.10 mm−1
b = 14.1723 (8) ÅT = 296 K
c = 6.2357 (3) Å0.25 × 0.22 × 0.20 mm
β = 95.400 (2)°
Data collection top
Bruker Kappa APEXII CCD
diffractometer		2238 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2005)		1395 reflections with I > 2σ(I)
Tmin = 0.976, Tmax = 0.985Rint = 0.041
9733 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0490 restraints
wR(F2) = 0.133H atoms treated by a mixture of independent and constrained refinement
S = 1.03Δρmax = 0.20 e Å−3
2238 reflectionsΔρmin = −0.18 e Å−3
181 parameters
Special details top

Geometry. Bond distances, angles etc. have been calculated using the rounded fractional coordinates. All su's are estimated from the variances of the (full) variance-covariance matrix. The cell e.s.d.'s are taken into account in the estimation of distances, angles and torsion angles

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
xyzUiso*/UeqOcc. (<1)
O10.18732 (12)0.66637 (13)0.3141 (3)0.0536 (6)
O2−0.21627 (11)0.59616 (18)0.6085 (3)0.0928 (9)
O3−0.13153 (11)0.55621 (14)0.8965 (3)0.0676 (7)
N10.28626 (12)0.62025 (13)0.6653 (3)0.0406 (6)
N2−0.13922 (12)0.58577 (15)0.7115 (3)0.0499 (7)
C10.37651 (14)0.62162 (15)0.7884 (3)0.0379 (7)
C20.45601 (14)0.59352 (16)0.6902 (4)0.0452 (8)
C30.54536 (15)0.59847 (17)0.8003 (4)0.0507 (9)
C40.55810 (15)0.63374 (16)1.0085 (4)0.0465 (8)
C50.47796 (15)0.66189 (16)1.1032 (3)0.0453 (8)
C60.38783 (14)0.65645 (16)0.9965 (3)0.0429 (8)
C70.65595 (16)0.6427 (2)1.1264 (4)0.0708 (10)
C80.20829 (14)0.60487 (15)0.7508 (3)0.0394 (7)
C90.11702 (14)0.61460 (15)0.6278 (3)0.0353 (7)
C100.11017 (15)0.64786 (15)0.4120 (3)0.0392 (7)
C110.01983 (15)0.66214 (15)0.3029 (3)0.0431 (8)
C12−0.06138 (15)0.64214 (15)0.3987 (3)0.0431 (8)
C13−0.05334 (14)0.60742 (15)0.6096 (3)0.0382 (7)
C140.03375 (13)0.59379 (15)0.7226 (3)0.0365 (7)
H10.234 (4)0.652 (3)0.390 (10)0.0643*0.60 (4)
H20.449050.571220.549280.0542*
H30.598130.577820.733980.0608*
H50.485000.685231.243220.0544*
H60.334960.676051.063750.0515*
H7A0.653630.624141.273900.1061*
H7B0.676950.707051.120870.1061*
H7C0.699740.602701.059830.1061*
H80.210770.587130.894830.0472*
H110.014900.685610.163000.0517*
H12−0.121170.651490.324590.0517*
H140.037330.570650.862690.0438*
H1A0.274 (5)0.641 (4)0.518 (13)0.0487*0.40 (4)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0503 (10)0.0696 (13)0.0423 (10)−0.0045 (9)0.0123 (8)0.0082 (8)
O20.0349 (10)0.171 (2)0.0711 (13)0.0043 (12)−0.0028 (9)0.0236 (13)
O30.0485 (10)0.1043 (16)0.0511 (11)−0.0035 (9)0.0110 (8)0.0189 (10)
N10.0362 (10)0.0452 (12)0.0407 (11)0.0013 (8)0.0053 (8)0.0002 (9)
N20.0361 (10)0.0681 (14)0.0454 (12)−0.0001 (10)0.0039 (9)0.0003 (10)
C10.0328 (11)0.0393 (13)0.0417 (13)0.0008 (9)0.0045 (9)0.0027 (10)
C20.0424 (12)0.0507 (15)0.0435 (13)0.0027 (11)0.0094 (10)−0.0063 (11)
C30.0354 (12)0.0554 (16)0.0627 (16)0.0073 (11)0.0127 (11)−0.0019 (12)
C40.0390 (12)0.0473 (15)0.0524 (14)0.0023 (10)0.0008 (10)0.0044 (12)
C50.0457 (13)0.0513 (15)0.0391 (12)0.0015 (11)0.0044 (10)−0.0016 (11)
C60.0387 (12)0.0489 (14)0.0424 (13)0.0016 (10)0.0100 (10)−0.0003 (11)
C70.0458 (14)0.086 (2)0.0776 (19)0.0041 (14)−0.0102 (13)−0.0008 (16)
C80.0398 (12)0.0403 (14)0.0383 (12)0.0014 (10)0.0053 (10)0.0032 (10)
C90.0350 (11)0.0356 (12)0.0351 (12)−0.0005 (9)0.0030 (9)0.0003 (9)
C100.0432 (12)0.0378 (13)0.0372 (12)−0.0030 (10)0.0077 (10)−0.0014 (10)
C110.0537 (14)0.0440 (14)0.0309 (11)−0.0015 (11)0.0005 (10)0.0046 (10)
C120.0427 (12)0.0441 (14)0.0406 (13)0.0014 (10)−0.0067 (10)−0.0023 (10)
C130.0351 (11)0.0422 (14)0.0378 (12)−0.0019 (9)0.0055 (9)−0.0025 (10)
C140.0392 (11)0.0394 (13)0.0308 (11)−0.0002 (10)0.0029 (9)0.0007 (9)
Geometric parameters (Å, º) top
O1—C101.320 (3)C9—C101.421 (3)
O2—N21.215 (2)C10—C111.398 (3)
O3—N21.223 (3)C11—C121.367 (3)
O1—H10.80 (6)C12—C131.399 (3)
N1—C11.420 (3)C13—C141.368 (3)
N1—C81.282 (3)C2—H20.9300
N2—C131.449 (3)C3—H30.9300
N1—H1A0.96 (8)C5—H50.9300
C1—C21.383 (3)C6—H60.9300
C1—C61.384 (3)C7—H7A0.9600
C2—C31.376 (3)C7—H7B0.9600
C3—C41.387 (3)C7—H7C0.9600
C4—C51.380 (3)C8—H80.9300
C4—C71.503 (3)C11—H110.9300
C5—C61.377 (3)C12—H120.9300
C8—C91.439 (3)C14—H140.9300
C9—C141.392 (3)
C10—O1—H1110 (4)N2—C13—C12119.32 (18)
C1—N1—C8122.22 (18)N2—C13—C14119.13 (17)
O2—N2—O3122.38 (18)C12—C13—C14121.55 (18)
O3—N2—C13118.87 (17)C9—C14—C13119.96 (18)
O2—N2—C13118.74 (18)C1—C2—H2120.00
C8—N1—H1A111 (4)C3—C2—H2120.00
C1—N1—H1A126 (4)C2—C3—H3119.00
N1—C1—C2118.38 (18)C4—C3—H3119.00
N1—C1—C6122.00 (18)C4—C5—H5119.00
C2—C1—C6119.45 (19)C6—C5—H5119.00
C1—C2—C3120.2 (2)C1—C6—H6120.00
C2—C3—C4121.1 (2)C5—C6—H6120.00
C3—C4—C5117.8 (2)C4—C7—H7A109.00
C3—C4—C7121.3 (2)C4—C7—H7B109.00
C5—C4—C7120.9 (2)C4—C7—H7C109.00
C4—C5—C6121.92 (19)H7A—C7—H7B109.00
C1—C6—C5119.51 (18)H7A—C7—H7C109.00
N1—C8—C9121.13 (18)H7B—C7—H7C109.00
C8—C9—C14119.82 (17)N1—C8—H8119.00
C8—C9—C10120.96 (18)C9—C8—H8119.00
C10—C9—C14119.20 (18)C10—C11—H11119.00
O1—C10—C9121.23 (19)C12—C11—H11119.00
O1—C10—C11119.66 (18)C11—C12—H12120.00
C9—C10—C11119.11 (18)C13—C12—H12120.00
C10—C11—C12121.02 (18)C9—C14—H14120.00
C11—C12—C13119.13 (19)C13—C14—H14120.00
C8—N1—C1—C2149.4 (2)C4—C5—C6—C10.2 (3)
C8—N1—C1—C6−35.4 (3)N1—C8—C9—C10−4.4 (3)
C1—N1—C8—C9172.72 (19)N1—C8—C9—C14177.4 (2)
O2—N2—C13—C121.9 (3)C8—C9—C10—O13.4 (3)
O2—N2—C13—C14−178.5 (2)C8—C9—C10—C11−175.9 (2)
O3—N2—C13—C12−179.4 (2)C14—C9—C10—O1−178.4 (2)
O3—N2—C13—C140.3 (3)C14—C9—C10—C112.3 (3)
N1—C1—C2—C3176.6 (2)C8—C9—C14—C13176.8 (2)
C6—C1—C2—C31.3 (3)C10—C9—C14—C13−1.4 (3)
N1—C1—C6—C5−175.7 (2)O1—C10—C11—C12178.9 (2)
C2—C1—C6—C5−0.5 (3)C9—C10—C11—C12−1.8 (3)
C1—C2—C3—C4−1.7 (4)C10—C11—C12—C130.4 (3)
C2—C3—C4—C51.3 (3)C11—C12—C13—N2−179.76 (19)
C2—C3—C4—C7−177.7 (2)C11—C12—C13—C140.6 (3)
C3—C4—C5—C6−0.6 (3)N2—C13—C14—C9−179.70 (19)
C7—C4—C5—C6178.4 (2)C12—C13—C14—C90.0 (3)
Hydrogen-bond geometry (Å, º) top
Cg1 and Cg2 are the centroids of the C1—C6 and C9—C14 rings, respectively.
D—H···AD—HH···AD···AD—H···A
O1—H1···N10.80 (6)1.86 (6)2.566 (3)147 (6)
N1—H1A···O10.97 (8)1.71 (7)2.566 (3)146 (6)
C5—H5···Cg1i0.932.843.515 (2)130
C11—H11···Cg2ii0.932.823.490 (2)130
Symmetry codes: (i) x, −y+3/2, z+1/2; (ii) x, −y+3/2, z−1/2.

Experimental details

Crystal data
Chemical formula0.6C14H12N2O3·0.4C14H12N2O3
Mr256.26
Crystal system, space groupMonoclinic, P21/c
Temperature (K)296
a, b, c (Å)14.0623 (6), 14.1723 (8), 6.2357 (3)
β (°) 95.400 (2)
V (Å3)1237.23 (11)
Z4
Radiation typeMo Kα
µ (mm−1)0.10
Crystal size (mm)0.25 × 0.22 × 0.20
Data collection
DiffractometerBruker Kappa APEXII CCD
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 2005)
Tmin, Tmax0.976, 0.985
No. of measured, independent and
observed [I > 2σ(I)] reflections		9733, 2238, 1395
Rint0.041
(sin θ/λ)max (Å−1)0.600
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.049, 0.133, 1.03
No. of reflections2238
No. of parameters181
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å−3)0.20, −0.18

Computer programs: APEX2 (Bruker, 2009), SAINT (Bruker, 2009), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 1997) and PLATON (Spek, 2009), WinGX (Farrugia, 1999) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top
Cg1 and Cg2 are the centroids of the C1—C6 and C9—C14 rings, respectively.
D—H···AD—HH···AD···AD—H···A
O1—H1···N10.80 (6)1.86 (6)2.566 (3)147 (6)
N1—H1A···O10.97 (8)1.71 (7)2.566 (3)146 (6)
C5—H5···Cg1i0.932.843.515 (2)130
C11—H11···Cg2ii0.932.823.490 (2)130
Symmetry codes: (i) x, −y+3/2, z+1/2; (ii) x, −y+3/2, z−1/2.
 

Acknowledgements

The authors acknowledge the provision of funds for the purchase of diffractometer and encouragement by Dr Muhammad Akram Chaudhary, former Vice Chancellor, University of Sargodha, Pakistan.

References

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ISSN: 2056-9890
Volume 67| Part 9| September 2011| Page o2319
doi:10.1107/S1600536811032028
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