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

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ISSN: 2056-9890

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

(Received 27 October 2011; accepted 7 November 2011; online 9 November 2011)

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 Schiff bases, see: Blagus et al. (2010[Blagus, A., Cinčić, D., Friščić, T., Kaitner, B. & Stilinović, V. (2010). Maced. J. Chem. Chem. Eng. 29, 117-138.]). For similar structures derived from p-phenyl­enediamine, see: Al-Douh et al. (2009[Al-Douh, M. H., Osman, H., Hamid, S. A., Kia, R. & Fun, H.-K. (2009). Acta Cryst. E65, o680-o681.]); Hoshino et al. (1988[Hoshino, N., Inabe, T., Mitani, T. & Maruyama, Y. (1988). Bull. Chem. Soc. Jpn, 61, 4207-4214.]); Inabe et al. (1994[Inabe, T., Luneau, I., Mitani, T., Maruyama, Y. & Takeda, S. (1994). Bull. Chem. Soc. Jpn, 67, 612-621.]).

[Scheme 1]

Experimental

Crystal data
  • C32H24N2O2

  • Mr = 468.53

  • Orthorhombic, P c c n

  • a = 17.383 (4) Å

  • b = 14.595 (3) Å

  • c = 9.476 (2) Å

  • V = 2404.1 (9) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.08 mm−1

  • T = 298 K

  • 0.6 × 0.5 × 0.3 mm

Data collection
  • Oxford Diffraction Xcalibur CCD diffractometer

  • 18421 measured reflections

  • 2361 independent reflections

  • 1559 reflections with I > 2σ(I)

  • Rint = 0.053

Refinement
  • R[F2 > 2σ(F2)] = 0.052

  • wR(F2) = 0.149

  • S = 1.03

  • 2361 reflections

  • 166 parameters

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

  • Δρmax = 0.25 e Å−3

  • Δρmin = −0.19 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

Cg is the centroid of the C1–C6 ring.

D—H⋯A D—H H⋯A DA 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.

Data collection: CrysAlis CCD (Oxford Diffraction, 2003[Oxford Diffraction (2003). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Abingdon, England.]); cell refinement: CrysAlis RED (Oxford Diffraction, 2003[Oxford Diffraction (2003). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Abingdon, England.]); data reduction: CrysAlis RED; 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 (Farrugia, 1997[Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565.]); software used to prepare material for publication: WinGX (Farrugia, 1999[Farrugia, L. J. (1999). J. Appl. Cryst. 32, 837-838.]), PARST97 (Nardelli, 1995[Nardelli, M. (1995). J. Appl. Cryst. 28, 659.]) and Mercury (Macrae et al., 2006[Macrae, C. F., Edgington, P. R., McCabe, P., Pidcock, E., Shields, G. P., Taylor, R., Towler, M. & van de Streek, J. (2006). J. Appl. Cryst. 39, 453-457.]).

Supporting information


Comment top

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.

Related literature top

For general background to Schiff bases, 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).

Experimental top

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.

Refinement top

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).

Structure description top

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.

For general background to Schiff bases, 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).

Computing details top

Data collection: CrysAlis CCD (Oxford Diffraction, 2003); cell refinement: 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).

Figures top
[Figure 1] Fig. 1. ORTEP view of the title molecule with displacement ellipsoids drawn at the 50% probability level. Label a refers to the atoms with the symmetry code: –x, –y, –z + 1.
[Figure 2] Fig. 2. Stacking of (0 1 0) layers along the b-direction. In spite of non-planarity of the title molecule mutual molecular arrangement in neighboring layers corresponds to the herringbone motif typical for fused ring aromatic planar hydrocarbon molecules.
2-{[(4- {[(2-Hydroxyphenyl)(phenyl)methylidene]amino}phenyl)imino](phenyl)methyl}phenol top
Crystal data top
C32H24N2O2F(000) = 984
Mr = 468.53Dx = 1.294 Mg m3
Orthorhombic, PccnMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ab 2acCell parameters from 2361 reflections
a = 17.383 (4) Åθ = 4–26°
b = 14.595 (3) ŵ = 0.08 mm1
c = 9.476 (2) ÅT = 298 K
V = 2404.1 (9) Å3Prism, red-brown
Z = 40.6 × 0.5 × 0.3 mm
Data collection top
Oxford Diffraction Xcalibur CCD
diffractometer
1559 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.053
Graphite monochromatorθmax = 26.0°, θmin = 3.8°
ω scanh = 2121
18421 measured reflectionsk = 1815
2361 independent reflectionsl = 1111
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)] = 0.052Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.149H 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 parametersΔρmax = 0.25 e Å3
0 restraintsΔρmin = 0.19 e Å3
Crystal data top
C32H24N2O2V = 2404.1 (9) Å3
Mr = 468.53Z = 4
Orthorhombic, PccnMo Kα radiation
a = 17.383 (4) ŵ = 0.08 mm1
b = 14.595 (3) ÅT = 298 K
c = 9.476 (2) Å0.6 × 0.5 × 0.3 mm
Data collection top
Oxford Diffraction Xcalibur CCD
diffractometer
1559 reflections with I > 2σ(I)
18421 measured reflectionsRint = 0.053
2361 independent reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0520 restraints
wR(F2) = 0.149H atoms treated by a mixture of independent and constrained refinement
S = 1.03Δρmax = 0.25 e Å3
2361 reflectionsΔρmin = 0.19 e Å3
166 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
xyzUiso*/Ueq
O10.10687 (9)0.20165 (9)0.10710 (16)0.0382 (4)
H10.0915 (13)0.1651 (16)0.179 (3)0.046*
N10.07823 (10)0.05834 (11)0.25539 (18)0.0307 (4)
C10.13856 (11)0.04766 (13)0.0306 (2)0.0291 (5)
C20.13707 (12)0.14397 (13)0.0114 (2)0.0301 (5)
C30.16724 (13)0.18187 (14)0.1114 (2)0.0350 (5)
H30.16500.24490.12490.042*
C40.20034 (12)0.12759 (14)0.2129 (2)0.0362 (5)
H40.22040.15420.29410.043*
C50.20404 (12)0.03367 (14)0.1950 (2)0.0350 (5)
H50.22690.00300.26360.042*
C60.17364 (12)0.00509 (14)0.0750 (2)0.0328 (5)
H60.17640.06830.06360.039*
C70.10431 (12)0.00524 (13)0.1571 (2)0.0290 (5)
C80.10237 (12)0.09729 (13)0.1671 (2)0.0294 (5)
C90.05715 (13)0.14864 (14)0.0762 (2)0.0363 (6)
H90.02890.11960.00590.044*
C100.05388 (14)0.24324 (15)0.0898 (3)0.0417 (6)
H100.02210.27710.03060.050*
C110.09736 (14)0.28720 (15)0.1902 (3)0.0453 (6)
H110.09610.35070.19730.054*
C120.14278 (13)0.23687 (14)0.2802 (3)0.0441 (6)
H120.17230.26660.34810.053*
C130.14491 (12)0.14183 (14)0.2704 (2)0.0377 (6)
H130.17480.10810.33300.045*
C140.03947 (12)0.02512 (13)0.3774 (2)0.0289 (5)
C150.02406 (13)0.03231 (13)0.3698 (2)0.0319 (5)
H150.04070.05390.28260.038*
C160.06282 (12)0.05766 (14)0.4913 (2)0.0318 (5)
H160.10490.09680.48510.038*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0542 (10)0.0276 (8)0.0328 (9)0.0031 (7)0.0041 (8)0.0007 (7)
N10.0337 (10)0.0296 (9)0.0288 (10)0.0006 (8)0.0005 (8)0.0031 (8)
C10.0284 (11)0.0310 (11)0.0279 (12)0.0018 (9)0.0031 (9)0.0021 (9)
C20.0324 (12)0.0286 (11)0.0293 (12)0.0027 (9)0.0026 (10)0.0028 (9)
C30.0397 (13)0.0290 (11)0.0364 (13)0.0025 (10)0.0036 (11)0.0063 (10)
C40.0352 (12)0.0408 (13)0.0325 (12)0.0067 (10)0.0001 (10)0.0037 (10)
C50.0341 (12)0.0384 (13)0.0326 (13)0.0039 (10)0.0028 (10)0.0007 (10)
C60.0340 (12)0.0276 (11)0.0369 (13)0.0001 (9)0.0005 (10)0.0011 (9)
C70.0288 (11)0.0291 (11)0.0292 (12)0.0000 (9)0.0036 (9)0.0020 (9)
C80.0299 (11)0.0267 (11)0.0315 (11)0.0008 (9)0.0051 (10)0.0022 (9)
C90.0388 (13)0.0335 (12)0.0367 (13)0.0012 (10)0.0004 (11)0.0001 (10)
C100.0495 (15)0.0310 (12)0.0444 (15)0.0087 (11)0.0037 (12)0.0065 (11)
C110.0507 (15)0.0260 (11)0.0592 (17)0.0021 (11)0.0072 (13)0.0019 (11)
C120.0421 (14)0.0341 (13)0.0561 (16)0.0024 (10)0.0005 (12)0.0136 (11)
C130.0374 (13)0.0343 (12)0.0413 (13)0.0050 (10)0.0003 (11)0.0060 (10)
C140.0346 (12)0.0231 (10)0.0289 (12)0.0032 (9)0.0024 (9)0.0027 (9)
C150.0368 (13)0.0303 (11)0.0286 (12)0.0017 (10)0.0014 (10)0.0020 (9)
C160.0317 (12)0.0283 (11)0.0353 (13)0.0026 (9)0.0012 (10)0.0005 (9)
Geometric parameters (Å, º) top
O1—C21.344 (2)C8—C131.388 (3)
O1—H10.91 (2)C9—C101.388 (3)
N1—C71.294 (3)C9—H90.9300
N1—C141.423 (3)C10—C111.374 (3)
C1—C61.402 (3)C10—H100.9300
C1—C21.418 (3)C11—C121.375 (3)
C1—C71.474 (3)C11—H110.9300
C2—C31.391 (3)C12—C131.391 (3)
C3—C41.372 (3)C12—H120.9300
C3—H30.9300C13—H130.9300
C4—C51.383 (3)C14—C151.388 (3)
C4—H40.9300C14—C16i1.392 (3)
C5—C61.376 (3)C15—C161.384 (3)
C5—H50.9300C15—H150.9300
C6—H60.9300C16—C14i1.392 (3)
C7—C81.500 (3)C16—H160.9300
C8—C91.386 (3)
C2—O1—H1104.8 (15)C13—C8—C7119.99 (19)
C7—N1—C14123.14 (17)C8—C9—C10120.2 (2)
C6—C1—C2117.41 (18)C8—C9—H9119.9
C6—C1—C7121.68 (18)C10—C9—H9119.9
C2—C1—C7120.90 (18)C11—C10—C9120.4 (2)
O1—C2—C3117.56 (18)C11—C10—H10119.8
O1—C2—C1122.76 (18)C9—C10—H10119.8
C3—C2—C1119.67 (19)C10—C11—C12119.7 (2)
C4—C3—C2120.98 (19)C10—C11—H11120.1
C4—C3—H3119.5C12—C11—H11120.1
C2—C3—H3119.5C11—C12—C13120.4 (2)
C3—C4—C5120.4 (2)C11—C12—H12119.8
C3—C4—H4119.8C13—C12—H12119.8
C5—C4—H4119.8C8—C13—C12120.0 (2)
C6—C5—C4119.4 (2)C8—C13—H13120.0
C6—C5—H5120.3C12—C13—H13120.0
C4—C5—H5120.3C15—C14—C16i118.97 (18)
C5—C6—C1122.10 (19)C15—C14—N1122.68 (18)
C5—C6—H6118.9C16i—C14—N1118.15 (18)
C1—C6—H6118.9C16—C15—C14120.35 (19)
N1—C7—C1118.37 (18)C16—C15—H15119.8
N1—C7—C8122.98 (18)C14—C15—H15119.8
C1—C7—C8118.65 (17)C15—C16—C14i120.67 (19)
C9—C8—C13119.14 (19)C15—C16—H16119.7
C9—C8—C7120.86 (18)C14i—C16—H16119.7
C6—C1—C2—O1178.21 (19)N1—C7—C8—C9114.0 (2)
C7—C1—C2—O11.9 (3)C1—C7—C8—C967.0 (3)
C6—C1—C2—C32.3 (3)N1—C7—C8—C1364.5 (3)
C7—C1—C2—C3177.61 (19)C1—C7—C8—C13114.5 (2)
O1—C2—C3—C4178.80 (19)C13—C8—C9—C100.8 (3)
C1—C2—C3—C41.7 (3)C7—C8—C9—C10177.8 (2)
C2—C3—C4—C50.2 (3)C8—C9—C10—C112.2 (3)
C3—C4—C5—C60.5 (3)C9—C10—C11—C121.8 (4)
C4—C5—C6—C10.2 (3)C10—C11—C12—C130.1 (4)
C2—C1—C6—C51.6 (3)C9—C8—C13—C121.0 (3)
C7—C1—C6—C5178.34 (19)C7—C8—C13—C12179.6 (2)
C14—N1—C7—C1175.68 (17)C11—C12—C13—C81.5 (3)
C14—N1—C7—C85.3 (3)C7—N1—C14—C1553.9 (3)
C6—C1—C7—N1174.74 (19)C7—N1—C14—C16i131.3 (2)
C2—C1—C7—N15.3 (3)C16i—C14—C15—C160.9 (3)
C6—C1—C7—C84.3 (3)N1—C14—C15—C16175.61 (18)
C2—C1—C7—C8175.60 (19)C14—C15—C16—C14i0.9 (3)
Symmetry code: (i) x, y, z+1.
Hydrogen-bond geometry (Å, º) top
Cg is the centroid of the C1–C6 ring.
D—H···AD—HH···AD···AD—H···A
O1—H1···N10.91 (2)1.73 (2)2.569 (2)152 (2)
C15—H15···Cgii0.932.933.748 (2)148
Symmetry code: (ii) x, y, z.

Experimental details

Crystal data
Chemical formulaC32H24N2O2
Mr468.53
Crystal system, space groupOrthorhombic, Pccn
Temperature (K)298
a, b, c (Å)17.383 (4), 14.595 (3), 9.476 (2)
V3)2404.1 (9)
Z4
Radiation typeMo Kα
µ (mm1)0.08
Crystal size (mm)0.6 × 0.5 × 0.3
Data collection
DiffractometerOxford Diffraction Xcalibur CCD
Absorption correction
No. of measured, independent and
observed [I > 2σ(I)] reflections
18421, 2361, 1559
Rint0.053
(sin θ/λ)max1)0.617
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.052, 0.149, 1.03
No. of reflections2361
No. of parameters166
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)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).

Hydrogen-bond geometry (Å, º) top
Cg is the centroid of the C1–C6 ring.
D—H···AD—HH···AD···AD—H···A
O1—H1···N10.91 (2)1.73 (2)2.569 (2)152 (2)
C15—H15···Cgi0.932.933.748 (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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