organic compounds
2-{[(4-{[(2-Hydroxyphenyl)(phenyl)methylidene]amino}phenyl)imino](phenyl)methyl}phenol
aDepartment of Chemistry, J.J. Strossmayer University, Osijek, Franje Kuhača 20, HR-31000 Osijek, Croatia, and bLaboratory of General and Inorganic Chemistry, Department of Chemistry, Faculty of Science, University of Zagreb, Horvatovac 102a, HR-10002 Zagreb, Croatia
*Correspondence e-mail: ablagus@kemija.unios.hr
The title molecule, C32H24N2O2, has a crystallographically imposed inversion centre and exists in the crystal as an enol–imine tautomer. The molecular structure is stabilized by two strong intramolecular O—H⋯N hydrogen bonds. The dihedral angles between the central benzene ring and the mean planes of the phenyl substituents are 59.99 (1) and 62.79 (2)°. In the crystal, the molecules are arranged into (010) layers via C—H⋯π interactions.
Related literature
For general background to et al. (2010). For similar structures derived from p-phenylenediamine, see: Al-Douh et al. (2009); Hoshino et al. (1988); Inabe et al. (1994).
see: BlagusExperimental
Crystal data
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Data collection
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Refinement
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Data collection: CrysAlis CCD (Oxford Diffraction, 2003); cell CrysAlis RED (Oxford Diffraction, 2003); data reduction: CrysAlis RED; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997); software used to prepare material for publication: WinGX (Farrugia, 1999), PARST97 (Nardelli, 1995) and Mercury (Macrae et al., 2006).
Supporting information
https://doi.org/10.1107/S1600536811046988/gk2425sup1.cif
contains datablocks I, global. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536811046988/gk2425Isup2.hkl
Supporting information file. DOI: https://doi.org/10.1107/S1600536811046988/gk2425Isup3.cml
The title compound was prepared by the condensation reaction of the aromatic diamine and aromatic 2-OH-ketone in molar ratio 1: 2. Ethanolic solutions of 2-hydroxybenzophenone (10 mmol) and o-phenylenediamine (5 mmol) were stirred for 3 h. The resulting brown resinous product was dissolved in ether and overlaid with the same volume of n-hexane. After one month, red-brown crystals suitable for single-crystal X-ray analysis were obtained by slow evaporation from the solution. IR spectrum was recorded on Shimadzu FTIR-8400 spectrophotometer cm-1: 3378, 1625, 1486, 1335, 1246, 759, 702.
The O—H group hydrogen atom was located in a difference Fourier map and freely refined. The coordinates of H atoms bonded to C were calculated (C–H = 0.96 Å) and these H atoms were refined in a riding model approximation with Uiso(H) = 1.2Ueq (C).
There is constant interest in investigation of solid-state structures and properties of π interactions can be observed that organize the molecules into (0 1 0) layers shown in Fig. 2.
and their metal complexes (Blagus et al., 2010 and references therein). The title Schiff base is derived from p-phenylenediamine and the structures of three derived from p-phenylenediamine and different [(i) vanillin (Al-Douh et al., 2009), (ii) salicylaldehyde (Hoshino et al., 1988) and(iii) 2-OH-1-naphthaldehyde (Inabe et al., 1994)] were published since 1988. Two main features that define the shape of the title molecule are: (i) strong intramolecular O–H···N hydrogen bond and (ii) spatial orientation of four terminal aromatic rings with respect to the central one (Fig. 1). The C1–C6 ring and pseudo-aromatic O1–H1–N1–C1–C2–C7 ring are almost co-planar with a dihedral angle of 1.79 (1)° and the displacement of H1 atom from the best plane of pseudo-aromatic ring of 0.016 Å. The bond distances characterizing the enol-imine tautomeric form of (I) are as expected. Taking the central ring C14–C14i–C15–C15i–C16–C16i [(i): –x, –y, –z+1] as the pivotal one, the interplanar angles between this ring and the rings C1–C6 and C8–C13 are 59.99 (1) and 62.79 (2)°, respectively. The latter rings intersect at an angle of 67.74 (1)°. In crystal packing some weak C–H···For general background to
see: Blagus et al. (2010). For similar structures derived from p-phenylenediamine, see: Al-Douh et al. (2009); Hoshino et al. (1988); Inabe et al. (1994).Data collection: CrysAlis CCD (Oxford Diffraction, 2003); cell
CrysAlis RED (Oxford Diffraction, 2003); data reduction: CrysAlis RED (Oxford Diffraction, 2003); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997); software used to prepare material for publication: WinGX (Farrugia, 1999), PARST97 (Nardelli, 1995) and Mercury (Macrae et al., 2006).C32H24N2O2 | F(000) = 984 |
Mr = 468.53 | Dx = 1.294 Mg m−3 |
Orthorhombic, Pccn | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2ab 2ac | Cell parameters from 2361 reflections |
a = 17.383 (4) Å | θ = 4–26° |
b = 14.595 (3) Å | µ = 0.08 mm−1 |
c = 9.476 (2) Å | T = 298 K |
V = 2404.1 (9) Å3 | Prism, red-brown |
Z = 4 | 0.6 × 0.5 × 0.3 mm |
Oxford Diffraction Xcalibur CCD diffractometer | 1559 reflections with I > 2σ(I) |
Radiation source: fine-focus sealed tube | Rint = 0.053 |
Graphite monochromator | θmax = 26.0°, θmin = 3.8° |
ω scan | h = −21→21 |
18421 measured reflections | k = −18→15 |
2361 independent reflections | l = −11→11 |
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)] = 0.052 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.149 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.03 | w = 1/[σ2(Fo2) + (0.0869P)2] where P = (Fo2 + 2Fc2)/3 |
2361 reflections | (Δ/σ)max < 0.001 |
166 parameters | Δρmax = 0.25 e Å−3 |
0 restraints | Δρmin = −0.19 e Å−3 |
C32H24N2O2 | V = 2404.1 (9) Å3 |
Mr = 468.53 | Z = 4 |
Orthorhombic, Pccn | Mo Kα radiation |
a = 17.383 (4) Å | µ = 0.08 mm−1 |
b = 14.595 (3) Å | T = 298 K |
c = 9.476 (2) Å | 0.6 × 0.5 × 0.3 mm |
Oxford Diffraction Xcalibur CCD diffractometer | 1559 reflections with I > 2σ(I) |
18421 measured reflections | Rint = 0.053 |
2361 independent reflections |
R[F2 > 2σ(F2)] = 0.052 | 0 restraints |
wR(F2) = 0.149 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.03 | Δρmax = 0.25 e Å−3 |
2361 reflections | Δρmin = −0.19 e Å−3 |
166 parameters |
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. |
x | y | z | Uiso*/Ueq | ||
O1 | 0.10687 (9) | 0.20165 (9) | 0.10710 (16) | 0.0382 (4) | |
H1 | 0.0915 (13) | 0.1651 (16) | 0.179 (3) | 0.046* | |
N1 | 0.07823 (10) | 0.05834 (11) | 0.25539 (18) | 0.0307 (4) | |
C1 | 0.13856 (11) | 0.04766 (13) | 0.0306 (2) | 0.0291 (5) | |
C2 | 0.13707 (12) | 0.14397 (13) | 0.0114 (2) | 0.0301 (5) | |
C3 | 0.16724 (13) | 0.18187 (14) | −0.1114 (2) | 0.0350 (5) | |
H3 | 0.1650 | 0.2449 | −0.1249 | 0.042* | |
C4 | 0.20034 (12) | 0.12759 (14) | −0.2129 (2) | 0.0362 (5) | |
H4 | 0.2204 | 0.1542 | −0.2941 | 0.043* | |
C5 | 0.20404 (12) | 0.03367 (14) | −0.1950 (2) | 0.0350 (5) | |
H5 | 0.2269 | −0.0030 | −0.2636 | 0.042* | |
C6 | 0.17364 (12) | −0.00509 (14) | −0.0750 (2) | 0.0328 (5) | |
H6 | 0.1764 | −0.0683 | −0.0636 | 0.039* | |
C7 | 0.10431 (12) | 0.00524 (13) | 0.1571 (2) | 0.0290 (5) | |
C8 | 0.10237 (12) | −0.09729 (13) | 0.1671 (2) | 0.0294 (5) | |
C9 | 0.05715 (13) | −0.14864 (14) | 0.0762 (2) | 0.0363 (6) | |
H9 | 0.0289 | −0.1196 | 0.0059 | 0.044* | |
C10 | 0.05388 (14) | −0.24324 (15) | 0.0898 (3) | 0.0417 (6) | |
H10 | 0.0221 | −0.2771 | 0.0306 | 0.050* | |
C11 | 0.09736 (14) | −0.28720 (15) | 0.1902 (3) | 0.0453 (6) | |
H11 | 0.0961 | −0.3507 | 0.1973 | 0.054* | |
C12 | 0.14278 (13) | −0.23687 (14) | 0.2802 (3) | 0.0441 (6) | |
H12 | 0.1723 | −0.2666 | 0.3481 | 0.053* | |
C13 | 0.14491 (12) | −0.14183 (14) | 0.2704 (2) | 0.0377 (6) | |
H13 | 0.1748 | −0.1081 | 0.3330 | 0.045* | |
C14 | 0.03947 (12) | 0.02512 (13) | 0.3774 (2) | 0.0289 (5) | |
C15 | −0.02406 (13) | −0.03231 (13) | 0.3698 (2) | 0.0319 (5) | |
H15 | −0.0407 | −0.0539 | 0.2826 | 0.038* | |
C16 | −0.06282 (12) | −0.05766 (14) | 0.4913 (2) | 0.0318 (5) | |
H16 | −0.1049 | −0.0968 | 0.4851 | 0.038* |
U11 | U22 | U33 | U12 | U13 | U23 | |
O1 | 0.0542 (10) | 0.0276 (8) | 0.0328 (9) | −0.0031 (7) | 0.0041 (8) | 0.0007 (7) |
N1 | 0.0337 (10) | 0.0296 (9) | 0.0288 (10) | −0.0006 (8) | 0.0005 (8) | 0.0031 (8) |
C1 | 0.0284 (11) | 0.0310 (11) | 0.0279 (12) | −0.0018 (9) | −0.0031 (9) | 0.0021 (9) |
C2 | 0.0324 (12) | 0.0286 (11) | 0.0293 (12) | −0.0027 (9) | −0.0026 (10) | −0.0028 (9) |
C3 | 0.0397 (13) | 0.0290 (11) | 0.0364 (13) | −0.0025 (10) | −0.0036 (11) | 0.0063 (10) |
C4 | 0.0352 (12) | 0.0408 (13) | 0.0325 (12) | −0.0067 (10) | −0.0001 (10) | 0.0037 (10) |
C5 | 0.0341 (12) | 0.0384 (13) | 0.0326 (13) | 0.0039 (10) | 0.0028 (10) | 0.0007 (10) |
C6 | 0.0340 (12) | 0.0276 (11) | 0.0369 (13) | 0.0001 (9) | −0.0005 (10) | 0.0011 (9) |
C7 | 0.0288 (11) | 0.0291 (11) | 0.0292 (12) | 0.0000 (9) | −0.0036 (9) | 0.0020 (9) |
C8 | 0.0299 (11) | 0.0267 (11) | 0.0315 (11) | 0.0008 (9) | 0.0051 (10) | 0.0022 (9) |
C9 | 0.0388 (13) | 0.0335 (12) | 0.0367 (13) | −0.0012 (10) | −0.0004 (11) | −0.0001 (10) |
C10 | 0.0495 (15) | 0.0310 (12) | 0.0444 (15) | −0.0087 (11) | 0.0037 (12) | −0.0065 (11) |
C11 | 0.0507 (15) | 0.0260 (11) | 0.0592 (17) | −0.0021 (11) | 0.0072 (13) | 0.0019 (11) |
C12 | 0.0421 (14) | 0.0341 (13) | 0.0561 (16) | 0.0024 (10) | −0.0005 (12) | 0.0136 (11) |
C13 | 0.0374 (13) | 0.0343 (12) | 0.0413 (13) | −0.0050 (10) | −0.0003 (11) | 0.0060 (10) |
C14 | 0.0346 (12) | 0.0231 (10) | 0.0289 (12) | 0.0032 (9) | 0.0024 (9) | 0.0027 (9) |
C15 | 0.0368 (13) | 0.0303 (11) | 0.0286 (12) | 0.0017 (10) | −0.0014 (10) | −0.0020 (9) |
C16 | 0.0317 (12) | 0.0283 (11) | 0.0353 (13) | −0.0026 (9) | 0.0012 (10) | 0.0005 (9) |
O1—C2 | 1.344 (2) | C8—C13 | 1.388 (3) |
O1—H1 | 0.91 (2) | C9—C10 | 1.388 (3) |
N1—C7 | 1.294 (3) | C9—H9 | 0.9300 |
N1—C14 | 1.423 (3) | C10—C11 | 1.374 (3) |
C1—C6 | 1.402 (3) | C10—H10 | 0.9300 |
C1—C2 | 1.418 (3) | C11—C12 | 1.375 (3) |
C1—C7 | 1.474 (3) | C11—H11 | 0.9300 |
C2—C3 | 1.391 (3) | C12—C13 | 1.391 (3) |
C3—C4 | 1.372 (3) | C12—H12 | 0.9300 |
C3—H3 | 0.9300 | C13—H13 | 0.9300 |
C4—C5 | 1.383 (3) | C14—C15 | 1.388 (3) |
C4—H4 | 0.9300 | C14—C16i | 1.392 (3) |
C5—C6 | 1.376 (3) | C15—C16 | 1.384 (3) |
C5—H5 | 0.9300 | C15—H15 | 0.9300 |
C6—H6 | 0.9300 | C16—C14i | 1.392 (3) |
C7—C8 | 1.500 (3) | C16—H16 | 0.9300 |
C8—C9 | 1.386 (3) | ||
C2—O1—H1 | 104.8 (15) | C13—C8—C7 | 119.99 (19) |
C7—N1—C14 | 123.14 (17) | C8—C9—C10 | 120.2 (2) |
C6—C1—C2 | 117.41 (18) | C8—C9—H9 | 119.9 |
C6—C1—C7 | 121.68 (18) | C10—C9—H9 | 119.9 |
C2—C1—C7 | 120.90 (18) | C11—C10—C9 | 120.4 (2) |
O1—C2—C3 | 117.56 (18) | C11—C10—H10 | 119.8 |
O1—C2—C1 | 122.76 (18) | C9—C10—H10 | 119.8 |
C3—C2—C1 | 119.67 (19) | C10—C11—C12 | 119.7 (2) |
C4—C3—C2 | 120.98 (19) | C10—C11—H11 | 120.1 |
C4—C3—H3 | 119.5 | C12—C11—H11 | 120.1 |
C2—C3—H3 | 119.5 | C11—C12—C13 | 120.4 (2) |
C3—C4—C5 | 120.4 (2) | C11—C12—H12 | 119.8 |
C3—C4—H4 | 119.8 | C13—C12—H12 | 119.8 |
C5—C4—H4 | 119.8 | C8—C13—C12 | 120.0 (2) |
C6—C5—C4 | 119.4 (2) | C8—C13—H13 | 120.0 |
C6—C5—H5 | 120.3 | C12—C13—H13 | 120.0 |
C4—C5—H5 | 120.3 | C15—C14—C16i | 118.97 (18) |
C5—C6—C1 | 122.10 (19) | C15—C14—N1 | 122.68 (18) |
C5—C6—H6 | 118.9 | C16i—C14—N1 | 118.15 (18) |
C1—C6—H6 | 118.9 | C16—C15—C14 | 120.35 (19) |
N1—C7—C1 | 118.37 (18) | C16—C15—H15 | 119.8 |
N1—C7—C8 | 122.98 (18) | C14—C15—H15 | 119.8 |
C1—C7—C8 | 118.65 (17) | C15—C16—C14i | 120.67 (19) |
C9—C8—C13 | 119.14 (19) | C15—C16—H16 | 119.7 |
C9—C8—C7 | 120.86 (18) | C14i—C16—H16 | 119.7 |
C6—C1—C2—O1 | −178.21 (19) | N1—C7—C8—C9 | 114.0 (2) |
C7—C1—C2—O1 | 1.9 (3) | C1—C7—C8—C9 | −67.0 (3) |
C6—C1—C2—C3 | 2.3 (3) | N1—C7—C8—C13 | −64.5 (3) |
C7—C1—C2—C3 | −177.61 (19) | C1—C7—C8—C13 | 114.5 (2) |
O1—C2—C3—C4 | 178.80 (19) | C13—C8—C9—C10 | 0.8 (3) |
C1—C2—C3—C4 | −1.7 (3) | C7—C8—C9—C10 | −177.8 (2) |
C2—C3—C4—C5 | 0.2 (3) | C8—C9—C10—C11 | −2.2 (3) |
C3—C4—C5—C6 | 0.5 (3) | C9—C10—C11—C12 | 1.8 (4) |
C4—C5—C6—C1 | 0.2 (3) | C10—C11—C12—C13 | 0.1 (4) |
C2—C1—C6—C5 | −1.6 (3) | C9—C8—C13—C12 | 1.0 (3) |
C7—C1—C6—C5 | 178.34 (19) | C7—C8—C13—C12 | 179.6 (2) |
C14—N1—C7—C1 | 175.68 (17) | C11—C12—C13—C8 | −1.5 (3) |
C14—N1—C7—C8 | −5.3 (3) | C7—N1—C14—C15 | −53.9 (3) |
C6—C1—C7—N1 | 174.74 (19) | C7—N1—C14—C16i | 131.3 (2) |
C2—C1—C7—N1 | −5.3 (3) | C16i—C14—C15—C16 | −0.9 (3) |
C6—C1—C7—C8 | −4.3 (3) | N1—C14—C15—C16 | −175.61 (18) |
C2—C1—C7—C8 | 175.60 (19) | C14—C15—C16—C14i | 0.9 (3) |
Symmetry code: (i) −x, −y, −z+1. |
Cg is the centroid of the C1–C6 ring. |
D—H···A | D—H | H···A | D···A | D—H···A |
O1—H1···N1 | 0.91 (2) | 1.73 (2) | 2.569 (2) | 152 (2) |
C15—H15···Cgii | 0.93 | 2.93 | 3.748 (2) | 148 |
Symmetry code: (ii) −x, −y, −z. |
Experimental details
Crystal data | |
Chemical formula | C32H24N2O2 |
Mr | 468.53 |
Crystal system, space group | Orthorhombic, Pccn |
Temperature (K) | 298 |
a, b, c (Å) | 17.383 (4), 14.595 (3), 9.476 (2) |
V (Å3) | 2404.1 (9) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 0.08 |
Crystal size (mm) | 0.6 × 0.5 × 0.3 |
Data collection | |
Diffractometer | Oxford Diffraction Xcalibur CCD |
Absorption correction | – |
No. of measured, independent and observed [I > 2σ(I)] reflections | 18421, 2361, 1559 |
Rint | 0.053 |
(sin θ/λ)max (Å−1) | 0.617 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.052, 0.149, 1.03 |
No. of reflections | 2361 |
No. of parameters | 166 |
H-atom treatment | H atoms treated by a mixture of independent and constrained refinement |
Δρmax, Δρmin (e Å−3) | 0.25, −0.19 |
Computer programs: CrysAlis CCD (Oxford Diffraction, 2003), CrysAlis RED (Oxford Diffraction, 2003), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997), WinGX (Farrugia, 1999), PARST97 (Nardelli, 1995) and Mercury (Macrae et al., 2006).
Cg is the centroid of the C1–C6 ring. |
D—H···A | D—H | H···A | D···A | D—H···A |
O1—H1···N1 | 0.91 (2) | 1.73 (2) | 2.569 (2) | 152 (2) |
C15—H15···Cgi | 0.93 | 2.93 | 3.748 (2) | 148 |
Symmetry code: (i) −x, −y, −z. |
Acknowledgements
Financial support by the Ministry of Science, Education and Sport of the Republic of Croatia is gratefully acknowledged (grant No. 119–1193079–3069).
References
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There is constant interest in investigation of solid-state structures and properties of Schiff bases and their metal complexes (Blagus et al., 2010 and references therein). The title Schiff base is derived from p-phenylenediamine and the structures of three Schiff bases derived from p-phenylenediamine and different aldehydes [(i) vanillin (Al-Douh et al., 2009), (ii) salicylaldehyde (Hoshino et al., 1988) and(iii) 2-OH-1-naphthaldehyde (Inabe et al., 1994)] were published since 1988. Two main features that define the shape of the title molecule are: (i) strong intramolecular O–H···N hydrogen bond and (ii) spatial orientation of four terminal aromatic rings with respect to the central one (Fig. 1). The C1–C6 ring and pseudo-aromatic O1–H1–N1–C1–C2–C7 ring are almost co-planar with a dihedral angle of 1.79 (1)° and the displacement of H1 atom from the best plane of pseudo-aromatic ring of 0.016 Å. The bond distances characterizing the enol-imine tautomeric form of (I) are as expected. Taking the central ring C14–C14i–C15–C15i–C16–C16i [(i): –x, –y, –z+1] as the pivotal one, the interplanar angles between this ring and the rings C1–C6 and C8–C13 are 59.99 (1) and 62.79 (2)°, respectively. The latter rings intersect at an angle of 67.74 (1)°. In crystal packing some weak C–H···π interactions can be observed that organize the molecules into (0 1 0) layers shown in Fig. 2.