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Acta Cryst. (2011). E67, o798    [ doi:10.1107/S1600536811007847 ]

2-[N-(4-{4-[(E)-(2-Hydroxybenzylidene)amino]phenoxy}phenyl)carboximidoyl]phenol

G. H. Shahverdizadeh and E. R. T. Tiekink

Abstract top

The molecular structure of the title Schiff base compound, C26H20N2O3, shows that respective methylidene residues are almost coplanar with the adjacent terminal benzene ring owing to the presence of intramolecular O-H...N hydrogen bonds [the N-C-C-C torsion angles are -6.6 (7) and -6.7 (7)°]. However, twists are exhibited about each methylidene and respective benzene ring connected to the central O atom; the dihedral angles formed between the two inner and two outer benzene rings are 54.6 (2) and 45.6 (3)°, respectively. The conformation about each of the C=N bonds [1.285 (5) and 1.295 (5) Å] is E. In the crystal, extensive C-H...[pi] contacts involving all benzene rings results in the formation of layers in the ac plane.

Comment top

In continuation of structural studies of Schiff base ligands (Prasath et al., 2010), attention is now directed to evaluating the structures of flexible derivatives (Chu & Huang, 2007; Xu et al., 2008) which have been shown, for example, to lead to helical coordination polymers (Chu & Huang, 2007). In this context the title compound (I) was prepared and characterized crystallographically.

The molecule of (I) is twisted at both the central O atom, and about each of the methylidene residues. Thus, the dihedral angle formed between the least-squares planes through the benzene rings directly connected to the central O atom is 54.6 (2) °. Similarly, the dihedral angles formed between the terminal benzene ring and the adjacent benzene ring are 51.6 (2) ° for each of C1–C6/C8–C13 and C14–C19/C21–C26. Finally, the dihedral angle formed between the terminal benzene rings is 45.6 (3) °. The conformation about each of the C═N bonds [N1═C7 is 1.285 (5) Å and N2═C20 is 1.295 (5) Å] is E. The presence of intramolecular O—H···N hydrogen bonds, Table 1, ensures co-planarity between the respective terminal benzene rings and methylidene residues as reflected in the C1—C2—C7—N1 and N2—C20—C21—C22 torsion angles of -6.6 (7) and -6.7 (7) °. respectively.

The crystal packing is dominated by C—H···π interactions, Table 1, whereby each of the four benzene rings accepts two such contacts. The result is the formation of layers in the ac plane, Fig. 2.

Related literature top

For related structures of Schiff base ligands, see: Chu & Huang (2007); Xu et al. (2008); Prasath et al. (2010). For specialized recrystallization techniques, see: Harrowfield et al. (1996).

Experimental top

A solution of 4,4'-diaminodiphenyl ether (10 mmol) in ethanol (50 ml) was added drop wise to a solution of salicylaldehyde (20 mmol) in ethanol (50 ml). The mixture was stirred for 6 h. The resulting solution was filtered to obtain a Schiff base which was dried. Crystals of the title compound were obtained by using the branched tube method (Harrowfield et al., 1996) where the Schiff base (5 mmol) was placed in the arm to be heated. Methanol was carefully added to fill both arms, and then the arm to be heated was placed in a bath at 333 K. After 2 days, yellow crystals were deposited in the cooler arm, which were filtered, washed with water and air dried.

Refinement top

The O– and C-bound H atoms were geometrically placed (O—H = 0.82 Å and C–H = 0.93 Å) and refined as riding with Uiso(H) = yUeq(parent atom) for y = 1.5 (O) and 1.2 (C).

Computing details top

Data collection: APEX2 (Bruker, 2007); cell refinement: SAINT (Bruker, 2007); data reduction: SAINT (Bruker, 2007); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997) and DIAMOND (Brandenburg, 2006); software used to prepare material for publication: publCIF (Westrip, 2010).

Figures top
[Figure 1] Fig. 1. The molecular structure of (I) showing the atom-labelling scheme and displacement ellipsoids at the 35% probability level.
[Figure 2] Fig. 2. View approximately in projection down the a axis of the unit-cell contents for (I). The C—H···π contacts are shown as purple dashed lines.
2-[N-(4-{4-[(E)-(2- hydroxybenzylidene)amino]phenoxy}phenyl)carboximidoyl]phenol top
Crystal data top
C26H20N2O3F(000) = 856
Mr = 408.44Dx = 1.341 Mg m−3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 806 reflections
a = 6.0234 (9) Åθ = 2.6–20.9°
b = 46.225 (7) ŵ = 0.09 mm−1
c = 9.4371 (11) ÅT = 293 K
β = 129.636 (7)°Prism, yellow
V = 2023.5 (5) Å30.35 × 0.24 × 0.08 mm
Z = 4
Data collection top
Bruker APEXII CCD
diffractometer		3567 independent reflections
Radiation source: fine-focus sealed tube1468 reflections with I > 2σ(I)
graphiteRint = 0.089
φ and ω scansθmax = 25.0°, θmin = 1.8°
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)		h = −7→7
Tmin = 0.856, Tmax = 1.000k = −54→31
10647 measured reflectionsl = −11→11
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)] = 0.069H-atom parameters constrained
wR(F2) = 0.242 w = 1/[σ2(Fo2) + (0.0859P)2]
where P = (Fo2 + 2Fc2)/3
S = 1.05(Δ/σ)max < 0.001
3567 reflectionsΔρmax = 0.33 e Å−3
283 parametersΔρmin = −0.31 e Å−3
0 restraintsExtinction correction: SHELXL, Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.012 (2)
Crystal data top
C26H20N2O3V = 2023.5 (5) Å3
Mr = 408.44Z = 4
Monoclinic, P21/cMo Kα radiation
a = 6.0234 (9) ŵ = 0.09 mm−1
b = 46.225 (7) ÅT = 293 K
c = 9.4371 (11) Å0.35 × 0.24 × 0.08 mm
β = 129.636 (7)°
Data collection top
Bruker APEXII CCD
diffractometer		3567 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)		1468 reflections with I > 2σ(I)
Tmin = 0.856, Tmax = 1.000Rint = 0.089
10647 measured reflectionsθmax = 25.0°
Refinement top
R[F2 > 2σ(F2)] = 0.069H-atom parameters constrained
wR(F2) = 0.242Δρmax = 0.33 e Å−3
S = 1.05Δρmin = −0.31 e Å−3
3567 reflectionsAbsolute structure: ?
283 parametersFlack parameter: ?
0 restraintsRogers parameter: ?
Special details top

Geometry. All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'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 > 2σ(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
O10.9581 (7)0.39134 (8)0.7320 (5)0.0577 (11)
H1o0.86940.37620.70750.087*
O20.1380 (6)0.24995 (7)0.6475 (4)0.0383 (9)
O30.7882 (8)0.10965 (8)0.5591 (5)0.0560 (11)
H3o0.74800.12450.58560.084*
N10.5304 (8)0.35847 (8)0.6345 (5)0.0365 (10)
N20.5548 (8)0.14148 (9)0.6585 (5)0.0384 (10)
C10.7827 (10)0.41395 (11)0.6882 (6)0.0405 (13)
C20.4989 (10)0.40991 (10)0.6172 (6)0.0339 (11)
C30.3264 (11)0.43421 (11)0.5699 (6)0.0428 (13)
H30.13670.43180.52210.051*
C40.4323 (12)0.46186 (11)0.5928 (7)0.0525 (15)
H40.31420.47790.55810.063*
C50.7160 (13)0.46527 (12)0.6678 (7)0.0545 (15)
H50.79030.48380.68660.065*
C60.8909 (12)0.44174 (12)0.7155 (7)0.0509 (15)
H61.08180.44440.76610.061*
C70.3857 (10)0.38160 (10)0.6009 (6)0.0372 (12)
H70.20210.38000.56490.045*
C80.4255 (9)0.33115 (10)0.6359 (6)0.0315 (11)
C90.4603 (9)0.30768 (10)0.5600 (6)0.0339 (11)
H90.54650.31040.50710.041*
C100.3696 (10)0.28052 (10)0.5618 (6)0.0366 (12)
H100.38780.26510.50670.044*
C110.2507 (9)0.27635 (9)0.6465 (6)0.0322 (12)
C120.2179 (9)0.29916 (10)0.7254 (6)0.0338 (12)
H120.13790.29620.78200.041*
C130.3047 (9)0.32640 (10)0.7197 (6)0.0349 (12)
H130.28230.34190.77260.042*
C140.2517 (10)0.22375 (10)0.6487 (6)0.0313 (12)
C150.5385 (10)0.21951 (10)0.7314 (6)0.0377 (13)
H150.66680.23500.78490.045*
C160.6329 (10)0.19221 (10)0.7340 (6)0.0352 (12)
H160.82510.18950.78780.042*
C170.4477 (9)0.16882 (10)0.6583 (6)0.0339 (12)
C180.1595 (9)0.17341 (10)0.5739 (6)0.0357 (12)
H180.03160.15790.52110.043*
C190.0608 (9)0.20082 (10)0.5677 (6)0.0349 (12)
H19−0.13310.20380.50920.042*
C200.4768 (10)0.11806 (10)0.6915 (6)0.0389 (13)
H200.36500.11940.72760.047*
C210.5609 (9)0.08991 (10)0.6732 (6)0.0348 (12)
C220.7033 (10)0.08644 (11)0.6017 (6)0.0386 (12)
C230.7609 (11)0.05915 (12)0.5731 (7)0.0485 (14)
H230.85220.05700.52310.058*
C240.6833 (11)0.03516 (12)0.6185 (7)0.0555 (16)
H240.72130.01680.59830.067*
C250.5489 (12)0.03808 (12)0.6941 (7)0.0549 (15)
H250.50310.02180.72840.066*
C260.4831 (11)0.06532 (11)0.7186 (6)0.0443 (13)
H260.38680.06730.76520.053*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.046 (2)0.053 (3)0.078 (3)0.0038 (19)0.041 (2)−0.001 (2)
O20.0476 (19)0.0225 (19)0.051 (2)0.0009 (16)0.0340 (18)0.0014 (14)
O30.072 (3)0.046 (3)0.075 (3)−0.003 (2)0.059 (2)−0.002 (2)
N10.043 (2)0.031 (2)0.036 (2)−0.003 (2)0.026 (2)−0.0042 (18)
N20.036 (2)0.034 (3)0.038 (2)−0.0007 (19)0.020 (2)−0.0003 (18)
C10.046 (3)0.038 (3)0.040 (3)−0.002 (3)0.029 (3)−0.003 (2)
C20.036 (3)0.029 (3)0.036 (3)−0.002 (2)0.023 (2)−0.001 (2)
C30.047 (3)0.034 (3)0.046 (3)0.000 (3)0.029 (3)−0.001 (2)
C40.070 (4)0.030 (3)0.053 (4)0.003 (3)0.037 (3)−0.002 (3)
C50.071 (4)0.039 (4)0.053 (4)−0.021 (3)0.039 (3)−0.007 (3)
C60.054 (3)0.051 (4)0.053 (4)−0.008 (3)0.036 (3)−0.001 (3)
C70.035 (3)0.035 (3)0.042 (3)0.002 (2)0.025 (2)−0.002 (2)
C80.032 (3)0.028 (3)0.031 (3)0.001 (2)0.019 (2)0.000 (2)
C90.040 (3)0.033 (3)0.036 (3)0.000 (2)0.027 (2)−0.002 (2)
C100.048 (3)0.029 (3)0.039 (3)0.006 (2)0.031 (3)0.000 (2)
C110.036 (3)0.028 (3)0.028 (3)0.002 (2)0.019 (2)0.001 (2)
C120.037 (3)0.034 (3)0.034 (3)0.003 (2)0.025 (2)−0.002 (2)
C130.044 (3)0.028 (3)0.036 (3)0.002 (2)0.027 (3)−0.006 (2)
C140.038 (3)0.027 (3)0.032 (3)0.002 (2)0.024 (3)0.001 (2)
C150.040 (3)0.032 (3)0.033 (3)−0.005 (2)0.019 (3)−0.001 (2)
C160.032 (3)0.029 (3)0.037 (3)−0.002 (2)0.019 (2)−0.002 (2)
C170.036 (3)0.037 (3)0.030 (3)0.001 (2)0.022 (2)−0.001 (2)
C180.039 (3)0.026 (3)0.039 (3)−0.006 (2)0.023 (2)−0.005 (2)
C190.032 (3)0.036 (3)0.034 (3)−0.003 (2)0.020 (2)0.000 (2)
C200.044 (3)0.036 (3)0.039 (3)−0.003 (3)0.028 (3)−0.001 (2)
C210.033 (3)0.031 (3)0.037 (3)−0.001 (2)0.020 (2)−0.001 (2)
C220.039 (3)0.032 (3)0.041 (3)0.002 (2)0.024 (3)0.000 (2)
C230.045 (3)0.046 (4)0.052 (4)0.006 (3)0.030 (3)−0.003 (3)
C240.049 (3)0.037 (4)0.059 (4)0.006 (3)0.025 (3)−0.005 (3)
C250.061 (4)0.032 (3)0.056 (4)−0.002 (3)0.030 (3)0.008 (3)
C260.052 (3)0.033 (3)0.048 (3)−0.003 (3)0.032 (3)0.005 (2)
Geometric parameters (Å, °) top
O1—C11.350 (5)C10—H100.9300
O1—H1o0.8200C11—C121.376 (6)
O2—C141.388 (5)C12—C131.378 (6)
O2—C111.399 (5)C12—H120.9300
O3—C221.356 (5)C13—H130.9300
O3—H3o0.8200C14—C191.381 (6)
N1—C71.285 (5)C14—C151.382 (6)
N1—C81.416 (6)C15—C161.378 (6)
N2—C201.295 (5)C15—H150.9300
N2—C171.418 (6)C16—C171.381 (6)
C1—C61.388 (7)C16—H160.9300
C1—C21.395 (6)C17—C181.389 (6)
C2—C31.396 (6)C18—C191.385 (6)
C2—C71.438 (6)C18—H180.9300
C3—C41.383 (6)C19—H190.9300
C3—H30.9300C20—C211.447 (6)
C4—C51.379 (7)C20—H200.9300
C4—H40.9300C21—C261.397 (6)
C5—C61.375 (7)C21—C221.398 (7)
C5—H50.9300C22—C231.380 (6)
C6—H60.9300C23—C241.374 (7)
C7—H70.9300C23—H230.9300
C8—C91.387 (6)C24—C251.386 (8)
C8—C131.392 (6)C24—H240.9300
C9—C101.374 (6)C25—C261.383 (7)
C9—H90.9300C25—H250.9300
C10—C111.385 (6)C26—H260.9300
C1—O1—H1o109.5C12—C13—H13119.5
C14—O2—C11121.5 (4)C8—C13—H13119.5
C22—O3—H3o109.5C19—C14—C15120.2 (4)
C7—N1—C8120.5 (4)C19—C14—O2115.6 (4)
C20—N2—C17120.7 (4)C15—C14—O2124.1 (4)
O1—C1—C6118.5 (5)C16—C15—C14119.5 (5)
O1—C1—C2121.6 (4)C16—C15—H15120.2
C6—C1—C2120.0 (5)C14—C15—H15120.2
C1—C2—C3118.7 (5)C15—C16—C17121.3 (4)
C1—C2—C7121.7 (4)C15—C16—H16119.3
C3—C2—C7119.5 (4)C17—C16—H16119.3
C4—C3—C2121.3 (5)C16—C17—C18118.6 (5)
C4—C3—H3119.4C16—C17—N2118.7 (4)
C2—C3—H3119.4C18—C17—N2122.5 (4)
C5—C4—C3118.9 (5)C19—C18—C17120.6 (4)
C5—C4—H4120.6C19—C18—H18119.7
C3—C4—H4120.6C17—C18—H18119.7
C6—C5—C4121.1 (5)C14—C19—C18119.7 (4)
C6—C5—H5119.4C14—C19—H19120.2
C4—C5—H5119.4C18—C19—H19120.2
C5—C6—C1120.0 (5)N2—C20—C21121.0 (5)
C5—C6—H6120.0N2—C20—H20119.5
C1—C6—H6120.0C21—C20—H20119.5
N1—C7—C2122.0 (4)C26—C21—C22118.9 (5)
N1—C7—H7119.0C26—C21—C20118.9 (5)
C2—C7—H7119.0C22—C21—C20122.0 (4)
C9—C8—C13118.4 (4)O3—C22—C23118.4 (5)
C9—C8—N1118.5 (4)O3—C22—C21121.1 (4)
C13—C8—N1122.9 (4)C23—C22—C21120.5 (5)
C10—C9—C8121.1 (4)C24—C23—C22119.9 (5)
C10—C9—H9119.5C24—C23—H23120.0
C8—C9—H9119.5C22—C23—H23120.0
C9—C10—C11119.4 (4)C23—C24—C25120.6 (5)
C9—C10—H10120.3C23—C24—H24119.7
C11—C10—H10120.3C25—C24—H24119.7
C12—C11—C10120.7 (4)C26—C25—C24119.9 (5)
C12—C11—O2115.3 (4)C26—C25—H25120.1
C10—C11—O2123.8 (4)C24—C25—H25120.1
C11—C12—C13119.4 (4)C25—C26—C21120.1 (5)
C11—C12—H12120.3C25—C26—H26119.9
C13—C12—H12120.3C21—C26—H26119.9
C12—C13—C8121.0 (4)
O1—C1—C2—C3−178.2 (4)C11—O2—C14—C19−151.5 (4)
C6—C1—C2—C31.9 (7)C11—O2—C14—C1531.5 (6)
O1—C1—C2—C75.1 (7)C19—C14—C15—C16−0.7 (7)
C6—C1—C2—C7−174.8 (5)O2—C14—C15—C16176.3 (4)
C1—C2—C3—C4−0.2 (7)C14—C15—C16—C17−1.1 (7)
C7—C2—C3—C4176.6 (4)C15—C16—C17—C181.8 (7)
C2—C3—C4—C5−1.5 (8)C15—C16—C17—N2177.5 (4)
C3—C4—C5—C61.6 (8)C20—N2—C17—C16140.5 (4)
C4—C5—C6—C10.1 (8)C20—N2—C17—C18−44.0 (6)
O1—C1—C6—C5178.3 (5)C16—C17—C18—C19−0.7 (7)
C2—C1—C6—C5−1.8 (7)N2—C17—C18—C19−176.2 (4)
C8—N1—C7—C2173.4 (4)C15—C14—C19—C181.7 (7)
C1—C2—C7—N1−6.6 (7)O2—C14—C19—C18−175.5 (4)
C3—C2—C7—N1176.7 (4)C17—C18—C19—C14−1.0 (7)
C7—N1—C8—C9140.4 (4)C17—N2—C20—C21173.5 (4)
C7—N1—C8—C13−43.6 (6)N2—C20—C21—C26177.0 (4)
C13—C8—C9—C102.1 (6)N2—C20—C21—C22−6.7 (7)
N1—C8—C9—C10178.3 (4)C26—C21—C22—O3−178.7 (4)
C8—C9—C10—C11−2.3 (7)C20—C21—C22—O35.0 (7)
C9—C10—C11—C121.2 (7)C26—C21—C22—C231.3 (7)
C9—C10—C11—O2176.5 (4)C20—C21—C22—C23−175.1 (4)
C14—O2—C11—C12−152.1 (4)O3—C22—C23—C24178.6 (4)
C14—O2—C11—C1032.4 (6)C21—C22—C23—C24−1.3 (8)
C10—C11—C12—C130.0 (7)C22—C23—C24—C25−0.4 (8)
O2—C11—C12—C13−175.7 (4)C23—C24—C25—C262.2 (8)
C11—C12—C13—C8−0.2 (7)C24—C25—C26—C21−2.3 (8)
C9—C8—C13—C12−0.9 (6)C22—C21—C26—C250.6 (7)
N1—C8—C13—C12−176.9 (4)C20—C21—C26—C25177.0 (4)
Hydrogen-bond geometry (Å, °) top
Cg1–Cg4 are the centroids of the C1—C6, C8–C13, C14–C19 and C21–C26 rings, respectively.
D—H···AD—HH···AD···AD—H···A
O1—H1o···N10.821.882.602 (5)147
O3—H3o···N20.821.862.589 (5)147
C23—H23···Cg1i0.932.903.556 (6)129
C26—H26···Cg1ii0.932.903.566 (6)129
C16—H16···Cg2iii0.932.763.469 (6)133
C19—H19···Cg2iv0.932.863.582 (5)135
C9—H9···Cg3i0.932.763.462 (5)133
C12—H12···Cg3ii0.932.883.584 (5)134
C3—H3···Cg4iv0.932.873.512 (6)128
C6—H6···Cg4iii0.932.953.626 (7)131
Symmetry codes: (i) x, −y−3/2, z−5/2; (ii) x, −y−3/2, z−3/2; (iii) x+1, −y−3/2, z−3/2; (iv) x−1, −y−3/2, z−5/2.
Table 1
Hydrogen-bond geometry (Å, °) top
Cg1–Cg4 are the centroids of the C1—C6, C8–C13, C14–C19 and C21–C26 rings, respectively.
D—H···AD—HH···AD···AD—H···A
O1—H1o···N10.821.882.602 (5)147
O3—H3o···N20.821.862.589 (5)147
C23—H23···Cg1i0.932.903.556 (6)129
C26—H26···Cg1ii0.932.903.566 (6)129
C16—H16···Cg2iii0.932.763.469 (6)133
C19—H19···Cg2iv0.932.863.582 (5)135
C9—H9···Cg3i0.932.763.462 (5)133
C12—H12···Cg3ii0.932.883.584 (5)134
C3—H3···Cg4iv0.932.873.512 (6)128
C6—H6···Cg4iii0.932.953.626 (7)131
Symmetry codes: (i) x, −y−3/2, z−5/2; (ii) x, −y−3/2, z−3/2; (iii) x+1, −y−3/2, z−3/2; (iv) x−1, −y−3/2, z−5/2.
Acknowledgements top

Tabriz Azad University is gratefully acknowledged for the support of this work.

references
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