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

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ISSN: 2056-9890
Volume 66| Part 10| October 2010| Pages o2553-o2554

2-Hy­dr­oxy-5-{[(E)-4-meth­­oxy­benzyl­­idene]aza­nium­yl}benzoate

aDepartment of Physics, University of Sargodha, Sargodha, Pakistan, and bDepartment of Chemistry, University of Sargodha, Sargodha, Pakistan
*Correspondence e-mail: dmntahir_uos@yahoo.com

(Received 2 September 2010; accepted 8 September 2010; online 11 September 2010)

In the title zwitterion, C15H13NO4, obtained from the condensation of 5-amino­salicylic acid and 4-meth­oxy­benz­alde­hyde, the 4-hydoxyanilinic group of the 5-amino­salicylic acid moiety and the 4-meth­oxy­benzaldehyde moiety are twisted with respect to one another, making a dihedral angle of 10.37 (7)°. The carboxyl­ate group makes a dihedral angle of 5.7 (2)° with the parent 4-hydoxyanilinic group. An intra­molecular O—H⋯O hydrogen bond forms an S(6) ring motif. In the crystal, inter­molecular C—H⋯O and N—H⋯O hydrogen bonds with R21(7) ring motifs link the mol­ecules into infinite chains extending along the c axis. The occurence of slipped ππ stacking between symmetry-related aromatic rings reinforces the packing.

Related literature

For the related structures, see: Ashiq et al. (2010[Ashiq, M. I., Hussain, I., Dixon, S., Light, M. E. & Kilburn, J. D. (2010). Acta Cryst. C66, o455-o458.]); Bryan et al. (1978[Bryan, R. F., Forcier, P. & Miller, R. W. (1978). J. Chem. Soc. Perkin Trans. 2, pp. 368-372.]). 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.]). For ππ stacking, see: Janiak (2000[Janiak, C. (2000). J. Chem. Soc. Dalton Trans. pp. 3885-3896.]).

[Scheme 1]

Experimental

Crystal data
  • C15H13NO4

  • Mr = 271.26

  • Monoclinic, P 21 /c

  • a = 13.4369 (12) Å

  • b = 8.5619 (8) Å

  • c = 12.6653 (11) Å

  • β = 118.004 (3)°

  • V = 1286.5 (2) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.10 mm−1

  • T = 296 K

  • 0.26 × 0.20 × 0.18 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 = 0.982, Tmax = 0.987

  • 9561 measured reflections

  • 2320 independent reflections

  • 1583 reflections with I > 2σ(I)

  • Rint = 0.031

Refinement
  • R[F2 > 2σ(F2)] = 0.050

  • wR(F2) = 0.143

  • S = 1.02

  • 2320 reflections

  • 182 parameters

  • H-atom parameters constrained

  • Δρmax = 0.28 e Å−3

  • Δρmin = −0.18 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
O3—H3⋯O1 0.90 1.62 2.4816 (19) 159
N1—H1⋯O2i 0.86 1.90 2.7408 (19) 166
C8—H8⋯O1ii 0.93 2.47 3.179 (2) 133
C14—H14⋯O2i 0.93 2.30 3.183 (2) 159
C15—H15A⋯O3iii 0.96 2.56 3.393 (3) 145
Symmetry codes: (i) [x, -y+{\script{1\over 2}}, z-{\script{1\over 2}}]; (ii) [-x, y-{\script{1\over 2}}, -z+{\script{1\over 2}}]; (iii) x+1, y-1, z.

Table 2
ππ stacking inter­actions (Å, °)

Cg1 and Cg2 are the centroids of the C2–C7 and C9–C14 rings, respectively.

CgCg centroid–centroid distance mean inter­planar distancea slippage angleb
Cg1⋯Cg1i 3.7848 (13) 3.428 (1) 25.1
Cg1⋯Cg2ii 3.8456 (13) 3.567 (1) 22.0
Symmetry codes: (i) −x, 1 − y, −z, (ii) −x, −y, −z. Notes: (a) distance from one plane to the neighbouring centroid; (b) angle subtended by the inter­centroid vector to the plane normal. For details, see: Janiak (2000[Janiak, C. (2000). J. Chem. Soc. Dalton Trans. pp. 3885-3896.]).

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; 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.

Supporting information


Comment top

The title compound (I) has been synthesized as a potential ligand which could be used with various metals.

The title compound (I) is a Zwitterion. In (I), the group A (C2—C7/N1/O3) of 5-aminosalicylic acid moiety and the 4-methoxybenzaldehyde moiety B (C8—C15/O4) are planar with r. m. s. deviations of 0.0076 and 0.0255 Å, respectively. The dihedral angle between A/B is 10.37 (7)°. The carboxylate group C (O1/C1/O2) is oriented at a dihedral angle of 5.73 (24)° with the parent group A (Fig. 1). The title molecule is closely related to p-[(p-methoxybenzylidene)amino]phenol (Bryan et al., 1978) and N-benzyl-N'-{6- [(4-carboxylatobenzyl)aminocarbonyl]-2-pyridylmethyl}guanidinium (Ashiq et al., 2010)

The values of the CO bond [1.241 (2), 1.269 (3) Å] are in agreement with the value, 1.235 (3)–1.261 (3) Å, reported for the N-benzyl-N'-{6- [(4-carboxylatobenzyl)aminocarbonyl]-2-pyridylmethyl}guanidinium (Ashiq et al., 2010). In the title compound S(6) ring motifs (Bernstein et al., 1995), is formed due to intramolecular H-bondings of O—H···O type (Table 1, Fig. 2). There exist R21(7) ring motif due to intermolecular H-bondings of C—H···O and N—H···O types linking the molecules to form infinite one dimensional chains extending along the crystallographic c-axis.

The occurence of slippest ππ stacking (Janiak, 2000) between symmetry related aromatic rings play an important role in stabilizing the packing.

Related literature top

For the related structures, see: Ashiq et al. (2010); Bryan et al. (1978). For graph-set notation, see: Bernstein et al. (1995). For ππ stacking, see: Janiak (2000).

Experimental top

Equimolar quantities of 5-aminosalicylic acid and 4-anisaldehyde were refluxed in methanol for 30 min resulting in clear brown solution. The solution was kept at room temperature which affoarded light brown prisms after 72 h.

Refinement top

All H atoms attached to C atoms and N atom were fixed geometrically and treated as riding with C—H = 0.95 Å (methyl) or 0.93 Å (aromatic) and N—H = 0.86 Å with Uiso(H) = 1.2Ueq(Caromatic or N) or Uiso(H) = 1.5Ueq(Cmethyl). H atoms of the hydroxyl group was located in difference Fourier maps and included in the subsequent refinement using restraints (O—H = 0.85 (1) Å) with Uiso(H) = 1.5Ueq(O). In the last cycles of refinement this hydrogen was treated as riding on its parent O atom.

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 the atom numbering scheme. The thermal ellipsoids are drawn at the 50% probability level. H-atoms are shown by small circles of arbitrary radii.
[Figure 2] Fig. 2. Partial packing view showing the hydrogen bonding pattern. Hydrogen bonds are shown as dashed lines. H atoms not involved in hydrogen bondngs have been omitted for clarity. [Symmetry codes: (i) x, -y+1/2, z-1/2; (ii) -x, y-1/2, -z+1/2; (iii) x+1, y-1, z].
2-Hydroxy-5-{[(E)-4-methoxybenzylidene]azaniumyl}benzoate top
Crystal data top
C15H13NO4F(000) = 568
Mr = 271.26Dx = 1.401 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 1583 reflections
a = 13.4369 (12) Åθ = 2.9–25.3°
b = 8.5619 (8) ŵ = 0.10 mm1
c = 12.6653 (11) ÅT = 296 K
β = 118.004 (3)°Prism, light brown
V = 1286.5 (2) Å30.26 × 0.20 × 0.18 mm
Z = 4
Data collection top
Bruker Kappa APEXII CCD
diffractometer
2320 independent reflections
Radiation source: fine-focus sealed tube1583 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.031
Detector resolution: 8.10 pixels mm-1θmax = 25.3°, θmin = 2.9°
ω scansh = 1516
Absorption correction: multi-scan
(SADABS; Bruker, 2005)
k = 1010
Tmin = 0.982, Tmax = 0.987l = 1510
9561 measured reflections
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.050Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.143H-atom parameters constrained
S = 1.02 w = 1/[σ2(Fo2) + (0.0831P)2 + 0.1187P]
where P = (Fo2 + 2Fc2)/3
2320 reflections(Δ/σ)max < 0.001
182 parametersΔρmax = 0.28 e Å3
0 restraintsΔρmin = 0.18 e Å3
Crystal data top
C15H13NO4V = 1286.5 (2) Å3
Mr = 271.26Z = 4
Monoclinic, P21/cMo Kα radiation
a = 13.4369 (12) ŵ = 0.10 mm1
b = 8.5619 (8) ÅT = 296 K
c = 12.6653 (11) Å0.26 × 0.20 × 0.18 mm
β = 118.004 (3)°
Data collection top
Bruker Kappa APEXII CCD
diffractometer
2320 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2005)
1583 reflections with I > 2σ(I)
Tmin = 0.982, Tmax = 0.987Rint = 0.031
9561 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0500 restraints
wR(F2) = 0.143H-atom parameters constrained
S = 1.02Δρmax = 0.28 e Å3
2320 reflectionsΔρmin = 0.18 e Å3
182 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 > 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*/Ueq
O10.19046 (12)0.62390 (19)0.15961 (12)0.0667 (5)
O20.03306 (11)0.49725 (16)0.27753 (10)0.0510 (4)
O30.29868 (11)0.56256 (18)0.05677 (12)0.0613 (5)
H30.27280.60150.01760.092*
O40.50744 (13)0.1897 (2)0.09919 (15)0.0857 (6)
N10.04782 (11)0.17725 (17)0.01733 (13)0.0405 (4)
H10.03290.12550.08130.049*
C10.11320 (15)0.5260 (2)0.17761 (15)0.0406 (5)
C20.11993 (13)0.4447 (2)0.06936 (14)0.0353 (4)
C30.21322 (15)0.4691 (2)0.04323 (16)0.0437 (5)
C40.21754 (16)0.3965 (3)0.14312 (17)0.0548 (6)
H40.27930.41280.21780.066*
C50.13155 (15)0.3009 (2)0.13273 (16)0.0507 (5)
H50.13500.25300.20020.061*
C60.03929 (14)0.2756 (2)0.02139 (15)0.0382 (4)
C70.03399 (13)0.3462 (2)0.07921 (15)0.0371 (4)
H70.02730.32760.15370.044*
C80.14683 (14)0.1574 (2)0.07203 (16)0.0421 (5)
H80.16270.21050.14230.051*
C90.23438 (14)0.0614 (2)0.07311 (16)0.0413 (5)
C100.33683 (16)0.0561 (3)0.17828 (17)0.0548 (6)
H100.34470.11160.24490.066*
C110.42584 (16)0.0289 (3)0.18534 (18)0.0633 (7)
H110.49340.03150.25620.076*
C120.41467 (16)0.1115 (3)0.08600 (18)0.0547 (6)
C130.31336 (17)0.1093 (3)0.01877 (18)0.0541 (5)
H130.30560.16650.08460.065*
C140.22442 (16)0.0231 (2)0.02569 (17)0.0476 (5)
H140.15700.02090.09670.057*
C150.5007 (2)0.2741 (4)0.0010 (3)0.1025 (10)
H15A0.57160.32430.02060.154*
H15B0.48360.20320.06600.154*
H15C0.44240.35150.02500.154*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0623 (9)0.0904 (12)0.0448 (8)0.0283 (9)0.0230 (7)0.0037 (8)
O20.0533 (8)0.0604 (9)0.0315 (7)0.0028 (7)0.0135 (6)0.0023 (6)
O30.0447 (8)0.0827 (11)0.0461 (8)0.0220 (7)0.0127 (7)0.0035 (7)
O40.0628 (10)0.1237 (15)0.0748 (11)0.0473 (10)0.0358 (9)0.0216 (11)
N10.0403 (8)0.0448 (9)0.0360 (8)0.0020 (7)0.0176 (7)0.0029 (7)
C10.0401 (10)0.0465 (11)0.0365 (10)0.0018 (9)0.0189 (9)0.0033 (8)
C20.0337 (9)0.0390 (10)0.0332 (9)0.0022 (8)0.0157 (8)0.0026 (8)
C30.0361 (9)0.0522 (12)0.0392 (10)0.0055 (9)0.0147 (8)0.0013 (9)
C40.0436 (11)0.0728 (14)0.0321 (10)0.0118 (11)0.0046 (9)0.0036 (10)
C50.0472 (11)0.0620 (13)0.0345 (10)0.0066 (10)0.0120 (9)0.0085 (9)
C60.0360 (9)0.0402 (10)0.0388 (10)0.0019 (8)0.0177 (8)0.0009 (8)
C70.0320 (9)0.0417 (10)0.0332 (9)0.0005 (8)0.0118 (8)0.0050 (8)
C80.0408 (10)0.0478 (11)0.0362 (10)0.0014 (9)0.0168 (8)0.0032 (8)
C90.0369 (10)0.0465 (11)0.0385 (10)0.0012 (8)0.0161 (8)0.0009 (8)
C100.0445 (11)0.0755 (15)0.0372 (11)0.0052 (10)0.0131 (9)0.0055 (10)
C110.0399 (11)0.0946 (18)0.0445 (12)0.0129 (11)0.0108 (10)0.0063 (12)
C120.0457 (11)0.0698 (14)0.0526 (13)0.0199 (11)0.0264 (10)0.0174 (11)
C130.0569 (12)0.0628 (13)0.0435 (11)0.0120 (11)0.0243 (10)0.0011 (10)
C140.0393 (10)0.0557 (12)0.0399 (10)0.0071 (9)0.0120 (9)0.0008 (9)
C150.103 (2)0.123 (2)0.107 (2)0.0604 (19)0.0700 (18)0.0201 (19)
Geometric parameters (Å, º) top
O1—C11.269 (2)C6—C71.381 (2)
O2—C11.242 (2)C7—H70.9300
O3—C31.343 (2)C8—C91.430 (2)
O3—H30.9015C8—H80.9300
O4—C121.354 (2)C9—C101.396 (2)
O4—C151.426 (3)C9—C141.396 (3)
N1—C81.291 (2)C10—C111.367 (3)
N1—C61.423 (2)C10—H100.9300
N1—H10.8600C11—C121.389 (3)
C1—C21.502 (2)C11—H110.9300
C2—C71.388 (2)C12—C131.385 (3)
C2—C31.404 (2)C13—C141.372 (3)
C3—C41.386 (3)C13—H130.9300
C4—C51.371 (3)C14—H140.9300
C4—H40.9300C15—H15A0.9600
C5—C61.390 (2)C15—H15B0.9600
C5—H50.9300C15—H15C0.9600
C3—O3—H3101.5N1—C8—H8117.0
C12—O4—C15118.07 (18)C9—C8—H8117.0
C8—N1—C6126.96 (16)C10—C9—C14118.36 (17)
C8—N1—H1116.5C10—C9—C8117.77 (17)
C6—N1—H1116.5C14—C9—C8123.85 (16)
O2—C1—O1123.99 (17)C11—C10—C9121.33 (19)
O2—C1—C2119.34 (16)C11—C10—H10119.3
O1—C1—C2116.65 (15)C9—C10—H10119.3
C7—C2—C3119.37 (16)C10—C11—C12119.54 (18)
C7—C2—C1120.59 (15)C10—C11—H11120.2
C3—C2—C1120.04 (15)C12—C11—H11120.2
O3—C3—C4118.93 (16)O4—C12—C13124.0 (2)
O3—C3—C2121.38 (16)O4—C12—C11115.99 (18)
C4—C3—C2119.68 (16)C13—C12—C11120.05 (18)
C5—C4—C3120.52 (17)C14—C13—C12120.22 (19)
C5—C4—H4119.7C14—C13—H13119.9
C3—C4—H4119.7C12—C13—H13119.9
C4—C5—C6120.05 (17)C13—C14—C9120.49 (17)
C4—C5—H5120.0C13—C14—H14119.8
C6—C5—H5120.0C9—C14—H14119.8
C7—C6—C5120.18 (16)O4—C15—H15A109.5
C7—C6—N1122.70 (15)O4—C15—H15B109.5
C5—C6—N1117.12 (16)H15A—C15—H15B109.5
C6—C7—C2120.18 (15)O4—C15—H15C109.5
C6—C7—H7119.9H15A—C15—H15C109.5
C2—C7—H7119.9H15B—C15—H15C109.5
N1—C8—C9126.07 (17)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O3—H3···O10.901.622.4816 (19)159
N1—H1···O2i0.861.902.7408 (19)166
C8—H8···O1ii0.932.473.179 (2)133
C14—H14···O2i0.932.303.183 (2)159
C15—H15A···O3iii0.962.563.393 (3)145
Symmetry codes: (i) x, y+1/2, z1/2; (ii) x, y1/2, z+1/2; (iii) x+1, y1, z.

Experimental details

Crystal data
Chemical formulaC15H13NO4
Mr271.26
Crystal system, space groupMonoclinic, P21/c
Temperature (K)296
a, b, c (Å)13.4369 (12), 8.5619 (8), 12.6653 (11)
β (°) 118.004 (3)
V3)1286.5 (2)
Z4
Radiation typeMo Kα
µ (mm1)0.10
Crystal size (mm)0.26 × 0.20 × 0.18
Data collection
DiffractometerBruker Kappa APEXII CCD
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 2005)
Tmin, Tmax0.982, 0.987
No. of measured, independent and
observed [I > 2σ(I)] reflections
9561, 2320, 1583
Rint0.031
(sin θ/λ)max1)0.600
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.050, 0.143, 1.02
No. of reflections2320
No. of parameters182
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.28, 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
D—H···AD—HH···AD···AD—H···A
O3—H3···O10.901.622.4816 (19)158.6
N1—H1···O2i0.861.902.7408 (19)166.4
C8—H8···O1ii0.932.473.179 (2)133.0
C14—H14···O2i0.932.303.183 (2)158.9
C15—H15A···O3iii0.962.563.393 (3)145.4
Symmetry codes: (i) x, y+1/2, z1/2; (ii) x, y1/2, z+1/2; (iii) x+1, y1, z.
ππ stacking interactions (Å, °) top
Cg1 and Cg2 are the centroids of the C2–C7 and C9–C14 rings, respectively.
Cg···Cgcentroid–centroid distancemean interplanar distanceaslippage angleb
Cg1···Cg1i3.7848 (13)3.428 (1)25.1
Cg1···Cg2ii3.8456 (13)3.567 (1)22.0
Symmetry codes: (i) -x, 1-y, -z, (ii) -x, -y, -z. Notes: (a) distance from one plane to the neighbouring centroid; (b) angle subtended by the intercentroid vector to the plane normal. For details, see: Janiak (2000).
 

Acknowledgements

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

References

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Volume 66| Part 10| October 2010| Pages o2553-o2554
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