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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 68| Part 4| April 2012| Page o1141
doi:10.1107/S1600536812010550

2-[N-(4-{4-[(2-Hy­dr­oxy-5-meth­­oxy­benzyl­­idene)amino]­benz­yl}phen­yl)carboximido­yl]-4-meth­­oxy­phenol

Ali Ourari,a Lotfi Baameur,a Gilles Bouetb and Magali Allainc*

aLaboratoire d'Electrochimie, d'Ingénierie Moléculaire et de Catalyse Redox (LEIMCR), Faculté des Sciences de l'Ingénieur, Université Farhat Abbas, Sétif 19000, Algeria, bLaboratoire SONAS, E.A. 921, Faculté de Pharmacie, 16 Boulevard Daviers, 49045 Angers Cedex 01, France, and cMOLTECH ANJOU UMR CNRS 6200, 2, bd Lavoisier, 49045 Angers Cedex, France
*Correspondence e-mail: alourari@yahoo.fr

(Received 14 September 2011; accepted 9 March 2012; online 24 March 2012)

In the title Schiff base, C29H26N2O4, the complete molecule is generated by a crystallographic twofold axis and is V-shaped. The planes of the benzene rings of the central diphenyl­methane unit make a dihedral angle of 78.11 (4)° while adjacent benzene and 5-meth­oxy­salicyl­idene rings are twisted with respect to each other by a dihedral angle of 11.84 (8)°. The Schiff base is in the enol–imino form and an intra­molecular O—H⋯N hydrogen bond is observed.

Related literature

For related bis-bidentate Schiff base ligand structures, see: Birkedal & Pattison (2006[Birkedal, H. & Pattison, P. (2006). Acta Cryst. C62, o139-o141.]); Shahverdizadeh & Tiekink (2011[Shahverdizadeh, G. H. & Tiekink, E. R. T. (2011). Acta Cryst. E67, o798.]). For Schiff base ligands, see: Chu & Huang (2007[Chu, Z. & Huang, W. (2007). J. Mol. Struct. 837, 15-22.]); Yoshida & Ichikawa, (1997[Yoshida, N. & Ichikawa, K. (1997). J. Chem. Soc. Chem. Commun. pp. 1091-1092.]); Kruger et al. (2001[Kruger, P. E., Martin, N. & Niuwenhuyzen, M. (2001). J. Chem. Soc. Dalton Trans. pp. 1966-1970.]); Moutet & Ourari (1997[Moutet, J. C. & Ourari, A. (1997). Electrochim. Acta, 42, 2525-2531.]). For applications of bis-bidentate Schiff base ligands, see: Lin et al. (2008[Lin, C. H., Chang, S. L., Hsieh, C. W. & Lee, H. H. (2008). Polymer, 49, 1220-1229.]); Sadeghi et al. (2003[Sadeghi, S., Eslahi, M., Naseri, M. A., Naeimi, H., Sharghi, H. & Shameli, A. (2003). Electroanalysis, 15, 1327-1333.]).

[Scheme 1]

Experimental

Crystal data

  • C29H26N2O4

  • Mr = 466.52

  • Monoclinic, C 2/c

  • a = 41.307 (4) Å

  • b = 4.5993 (3) Å

  • c = 12.2229 (13) Å

  • β = 93.653 (12)°

  • V = 2317.4 (4) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.09 mm−1

  • T = 293 K

  • 0.69 × 0.38 × 0.06 mm
Data collection

  • Stoe IPDS diffractometer

  • Absorption correction: gaussian (ABSGAUSS in PLATON; Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]) Tmin = 0.953, Tmax = 0.993

  • 10694 measured reflections

  • 2244 independent reflections

  • 1662 reflections with I > 2σ(I)

  • Rint = 0.037
Refinement

  • R[F2 > 2σ(F2)] = 0.039

  • wR(F2) = 0.116

  • S = 1.06

  • 2244 reflections

  • 160 parameters

  • H-atom parameters constrained

  • Δρmax = 0.17 e Å−3

  • Δρmin = −0.15 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A D⋯A D—H⋯A
O1—H1⋯N1 0.89 1.81 2.6177 (15) 151

Data collection: EXPOSE (Stoe & Cie, 1995[Stoe & Cie (1995). EXPOSE and X-RED. Stoe & Cie, Darmstadt, Germany.]); cell refinement: X-RED (Stoe & Cie, 1995[Stoe & Cie (1995). EXPOSE and X-RED. Stoe & Cie, Darmstadt, Germany.]); data reduction: X-RED; program(s) used to solve structure: SIR92 (Altomare et al., 1993[Altomare, A., Cascarano, G., Giacovazzo, C. & Guagliardi, A. (1993). J. Appl. Cryst. 26, 343-350.]); 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.]); software used to prepare material for publication: publCIF (Westrip, 2010[Westrip, S. P. (2010). J. Appl. Cryst. 43, 920-925.]).

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536812010550/qk2024sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536812010550/qk2024Isup2.hkl

checkCIF report


Comment top

Bis-bidentate Schiff base ligands have been extensively studied and used as building blocks in metallo-supramolecular chemistry (Birkedal & Pattison, 2006; Shahverdizadeh & Tiekink, 2011; Chu & Huang, 2007; Yoshida & Ichikawa, 1997; Kruger et al., 2001). These compounds were also used as thermosetting resins (Lin et al., 2008) and in ion selective membranes for detecting traces of copper (Sadeghi et al., 2003). We were interested in such ligands owing to their diverse applications in coordination chemistry, catalysis and electrocatalysis (Moutet & Ourari, 1997).

The molecule of the title compound is arranged around the two fold axis at 1/2, y, 3/4 of the unit cell and methylene carbon C14 coinciding with it. The molecule is V-shaped and has a dihedral angle of 78.11 (4)° between the two inner phenyl rings. The phenyl and the 5-methoxysalicylidene rings are slightly twisted with respect to each other by a dihedral angle of 11.84 (8)°. There are two symmetry equivalent intramolecular O-H···N hydrogen bonds. The bond lengths and bond angles within the molecule agree well with those of the closely related compounds C27H22N2O2 (CCDC refcode YEFWUC; Birkedal & Pattison, 2006) and C26H20N2O3 (Shahverdizadeh & Tiekink, 2011). In the unit cell, the molecules are tightly stacked one above the other along the short b-axis (b = 4.5993 (3) Å) and are held together in this direction by slipped π-π stacking interactions between the phenyl rings and the iminomethylidene groups. The architecture and space group of the title structure is identical with CCDC YEFWUC.

Related literature top

For related bis-bidentate Schiff base ligand structures, see: Birkedal & Pattison (2006); Shahverdizadeh & Tiekink (2011). For Schiff base ligands, see: Chu & Huang (2007); Yoshida & Ichikawa, (1997); Kruger et al. (2001); Moutet & Ourari (1997). For applications of bis-bidentate Schiff base ligands, see: Lin et al. (2008); Sadeghi et al. (2003).

Experimental top

5-Methoxysalicyaldehyde (98%), 4, 4'-diaminodiphenylmethane (97%), anhydrous ethanol were all purchased from Alfa aesar and used as received. 200 mg (1 mmol) of 4, 4'-diaminodiphenylmethane were dissolved in 10 ml of absolute ethanol. To this solution, 304 mg (2 mmol) of 5-methoxysalicyaldehyde in 5 ml of absolute ethanol was dropwisely added under stirring. Then, this mixture was heated for 15 min at 50 °C. The resulting yellow precipitate was recovered by filtration, washed several times with a small portions of EtOH and then with diethyl ether to give 443 mg (95%) of the title compound. Suitable crystals were obtained by slow evaporation of a solution in dichloromethane/ethanol (9/1, v /v).

Refinement top

All H atoms attached to C were fixed geometrically and treated as riding with C—H = 0.96 Å (methyl), 0.92 Å (methylene) or 0.93 Å (aromatic) with Uiso(H) = 1.2Ueq(C) or Uiso(H) = 1.5Ueq(methyl). The H atom of the hydroxyl group was initially refined using a soft restraint O—H = 0.89 (1) Å and Uiso(H) = 1.2Ueq(O). Then, in the last cycles of refinement, it was treated as riding on its parent O atom.

Structure description top

Bis-bidentate Schiff base ligands have been extensively studied and used as building blocks in metallo-supramolecular chemistry (Birkedal & Pattison, 2006; Shahverdizadeh & Tiekink, 2011; Chu & Huang, 2007; Yoshida & Ichikawa, 1997; Kruger et al., 2001). These compounds were also used as thermosetting resins (Lin et al., 2008) and in ion selective membranes for detecting traces of copper (Sadeghi et al., 2003). We were interested in such ligands owing to their diverse applications in coordination chemistry, catalysis and electrocatalysis (Moutet & Ourari, 1997).

The molecule of the title compound is arranged around the two fold axis at 1/2, y, 3/4 of the unit cell and methylene carbon C14 coinciding with it. The molecule is V-shaped and has a dihedral angle of 78.11 (4)° between the two inner phenyl rings. The phenyl and the 5-methoxysalicylidene rings are slightly twisted with respect to each other by a dihedral angle of 11.84 (8)°. There are two symmetry equivalent intramolecular O-H···N hydrogen bonds. The bond lengths and bond angles within the molecule agree well with those of the closely related compounds C27H22N2O2 (CCDC refcode YEFWUC; Birkedal & Pattison, 2006) and C26H20N2O3 (Shahverdizadeh & Tiekink, 2011). In the unit cell, the molecules are tightly stacked one above the other along the short b-axis (b = 4.5993 (3) Å) and are held together in this direction by slipped π-π stacking interactions between the phenyl rings and the iminomethylidene groups. The architecture and space group of the title structure is identical with CCDC YEFWUC.

For related bis-bidentate Schiff base ligand structures, see: Birkedal & Pattison (2006); Shahverdizadeh & Tiekink (2011). For Schiff base ligands, see: Chu & Huang (2007); Yoshida & Ichikawa, (1997); Kruger et al. (2001); Moutet & Ourari (1997). For applications of bis-bidentate Schiff base ligands, see: Lin et al. (2008); Sadeghi et al. (2003).

Computing details top

Data collection: EXPOSE (Stoe & Cie, 1995); cell refinement: X-RED (Stoe & Cie, 1995); data reduction: X-RED (Stoe & Cie, 1995); program(s) used to solve structure: SIR92 (Altomare et al., 1993); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997); software used to prepare material for publication: publCIF (Westrip, 2010).

Figures top
[Figure 1] Fig. 1. A molecule of the title compound with the atom-labelling scheme. Displacement ellipsoids are drawn at the 50% probability level. H atoms are represented as small spheres of arbitrary radii. Hydrogen bonds are shown as dashed lines. [Symmetry code: (i) -x + 1, y, -z + 3/2]
2-[N-(4-{4-[(2-Hydroxy-5- methoxybenzylidene)amino]benzyl}phenyl)carboximidoyl]-4-methoxyphenol top
Crystal data top
C29H26N2O4F(000) = 984
Mr = 466.52Dx = 1.337 Mg m−3
Monoclinic, C2/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2ycCell parameters from 8000 reflections
a = 41.307 (4) Åθ = 2.0–25.9°
b = 4.5993 (3) ŵ = 0.09 mm−1
c = 12.2229 (13) ÅT = 293 K
β = 93.653 (12)°Plate, yellow
V = 2317.4 (4) Å30.69 × 0.38 × 0.06 mm
Z = 4
Data collection top
Stoe IPDS
diffractometer		2244 independent reflections
Radiation source: normal-focus sealed tube1662 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.037
Detector resolution: 6.66 pixels mm-1θmax = 25.8°, θmin = 2.0°
0.6° φ scansh = −50→50
Absorption correction: gaussian
(PLATON-ABSGAUSS; Spek, 2009)		k = −5→5
Tmin = 0.953, Tmax = 0.993l = −14→15
10694 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)] = 0.039Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.116H-atom parameters constrained
S = 1.06 w = 1/[σ2(Fo2) + (0.072P)2 + 0.1658P]
where P = (Fo2 + 2Fc2)/3
2244 reflections(Δ/σ)max = 0.001
160 parametersΔρmax = 0.17 e Å−3
0 restraintsΔρmin = −0.15 e Å−3
Crystal data top
C29H26N2O4V = 2317.4 (4) Å3
Mr = 466.52Z = 4
Monoclinic, C2/cMo Kα radiation
a = 41.307 (4) ŵ = 0.09 mm−1
b = 4.5993 (3) ÅT = 293 K
c = 12.2229 (13) Å0.69 × 0.38 × 0.06 mm
β = 93.653 (12)°
Data collection top
Stoe IPDS
diffractometer		2244 independent reflections
Absorption correction: gaussian
(PLATON-ABSGAUSS; Spek, 2009)		1662 reflections with I > 2σ(I)
Tmin = 0.953, Tmax = 0.993Rint = 0.037
10694 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0390 restraints
wR(F2) = 0.116H-atom parameters constrained
S = 1.06Δρmax = 0.17 e Å−3
2244 reflectionsΔρmin = −0.15 e Å−3
160 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
O10.37635 (3)0.9988 (3)0.40329 (8)0.0634 (3)
H10.38810.86940.44230.076*
O20.28937 (3)1.4522 (3)0.68223 (9)0.0651 (4)
N10.40032 (2)0.7019 (2)0.57231 (8)0.0404 (3)
C10.35488 (3)1.1095 (3)0.47152 (10)0.0435 (3)
C20.33158 (3)1.3024 (4)0.43070 (11)0.0521 (4)
H20.33091.35380.35700.063*
C30.30928 (3)1.4206 (3)0.49763 (12)0.0502 (4)
H30.29361.54940.46870.060*
C40.31021 (3)1.3469 (3)0.60828 (11)0.0451 (3)
C50.33363 (3)1.1561 (3)0.64977 (11)0.0438 (3)
H50.33451.10920.72390.053*
C60.35595 (3)1.0324 (3)0.58312 (10)0.0377 (3)
C70.26320 (4)1.6273 (4)0.64047 (16)0.0725 (5)
H7A0.27151.80120.60910.109*
H7B0.24981.67790.69890.109*
H7C0.25061.52140.58510.109*
C80.37983 (3)0.8291 (3)0.63036 (10)0.0405 (3)
H80.38030.79020.70510.049*
C90.42351 (3)0.5050 (3)0.62024 (10)0.0381 (3)
C100.42235 (3)0.3824 (3)0.72409 (11)0.0460 (3)
H100.40530.42800.76730.055*
C110.44638 (3)0.1933 (3)0.76319 (11)0.0463 (3)
H110.44500.11110.83230.056*
C120.47241 (3)0.1226 (3)0.70280 (11)0.0411 (3)
C130.47310 (3)0.2425 (3)0.59852 (12)0.0489 (4)
H130.49020.19790.55560.059*
C140.44889 (3)0.4265 (3)0.55754 (11)0.0467 (4)
H140.44960.49890.48670.056*
C150.5000−0.0659 (4)0.75000.0474 (5)
H15A0.4922−0.16580.80760.057*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0703 (7)0.0835 (8)0.0375 (5)0.0297 (6)0.0109 (5)0.0061 (5)
O20.0592 (6)0.0793 (8)0.0583 (6)0.0268 (6)0.0149 (5)0.0052 (6)
N10.0401 (5)0.0405 (6)0.0402 (6)0.0025 (5)−0.0008 (4)−0.0006 (5)
C10.0460 (7)0.0490 (8)0.0353 (6)0.0034 (6)0.0015 (5)−0.0016 (6)
C20.0586 (8)0.0599 (10)0.0372 (7)0.0101 (7)−0.0021 (6)0.0062 (6)
C30.0472 (7)0.0528 (9)0.0496 (8)0.0094 (6)−0.0055 (6)0.0050 (6)
C40.0417 (6)0.0468 (8)0.0471 (7)0.0038 (6)0.0050 (6)−0.0013 (6)
C50.0463 (7)0.0481 (8)0.0370 (6)0.0028 (6)0.0029 (5)0.0038 (6)
C60.0387 (6)0.0378 (7)0.0363 (6)−0.0012 (5)−0.0011 (5)−0.0008 (5)
C70.0619 (10)0.0752 (12)0.0819 (12)0.0267 (9)0.0173 (9)0.0054 (10)
C80.0444 (7)0.0419 (8)0.0348 (6)0.0008 (6)−0.0003 (5)0.0013 (5)
C90.0380 (6)0.0358 (7)0.0399 (6)−0.0009 (5)−0.0026 (5)−0.0017 (5)
C100.0411 (7)0.0519 (9)0.0451 (7)0.0042 (6)0.0050 (5)0.0047 (6)
C110.0462 (7)0.0477 (8)0.0444 (7)−0.0017 (6)−0.0020 (6)0.0080 (6)
C120.0393 (7)0.0312 (7)0.0516 (7)−0.0039 (5)−0.0059 (5)−0.0040 (6)
C130.0471 (7)0.0487 (9)0.0515 (8)0.0076 (6)0.0075 (6)−0.0037 (6)
C140.0518 (7)0.0485 (9)0.0401 (7)0.0070 (6)0.0055 (6)0.0015 (6)
C150.0445 (10)0.0342 (11)0.0626 (12)0.000−0.0055 (9)0.000
Geometric parameters (Å, º) top
O1—C11.3548 (15)C7—H7B0.9600
O1—H10.8879C7—H7C0.9600
O2—C41.3754 (16)C8—H80.9300
O2—C71.4168 (19)C9—C141.3852 (17)
N1—C81.2802 (16)C9—C101.3926 (18)
N1—C91.4176 (16)C10—C111.3822 (19)
C1—C21.379 (2)C10—H100.9300
C1—C61.4074 (18)C11—C121.3814 (18)
C2—C31.3819 (19)C11—H110.9300
C2—H20.9300C12—C131.3908 (19)
C3—C41.392 (2)C12—C151.5161 (17)
C3—H30.9300C13—C141.3795 (19)
C4—C51.3787 (19)C13—H130.9300
C5—C61.3901 (18)C14—H140.9300
C5—H50.9300C15—C12i1.5161 (17)
C6—C81.4520 (18)C15—H15A0.9160
C7—H7A0.9600
C1—O1—H1106.2H7B—C7—H7C109.5
C4—O2—C7117.30 (12)N1—C8—C6122.03 (12)
C8—N1—C9121.08 (11)N1—C8—H8119.0
O1—C1—C2119.22 (12)C6—C8—H8119.0
O1—C1—C6121.38 (12)C14—C9—C10118.04 (12)
C2—C1—C6119.40 (12)C14—C9—N1116.95 (11)
C1—C2—C3121.01 (13)C10—C9—N1125.00 (11)
C1—C2—H2119.5C11—C10—C9120.28 (12)
C3—C2—H2119.5C11—C10—H10119.9
C2—C3—C4120.06 (13)C9—C10—H10119.9
C2—C3—H3120.0C12—C11—C10122.00 (13)
C4—C3—H3120.0C12—C11—H11119.0
O2—C4—C5115.87 (12)C10—C11—H11119.0
O2—C4—C3124.94 (13)C11—C12—C13117.28 (12)
C5—C4—C3119.19 (12)C11—C12—C15121.54 (11)
C4—C5—C6121.39 (12)C13—C12—C15121.11 (11)
C4—C5—H5119.3C14—C13—C12121.29 (12)
C6—C5—H5119.3C14—C13—H13119.4
C5—C6—C1118.95 (12)C12—C13—H13119.4
C5—C6—C8119.31 (11)C13—C14—C9121.04 (13)
C1—C6—C8121.75 (11)C13—C14—H14119.5
O2—C7—H7A109.5C9—C14—H14119.5
O2—C7—H7B109.5C12i—C15—C12110.27 (15)
H7A—C7—H7B109.5C12i—C15—H15A106.7
O2—C7—H7C109.5C12—C15—H15A106.6
H7A—C7—H7C109.5
C6—C8—N1—C9179.75 (11)
Symmetry code: (i) −x+1, y, −z+3/2.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1—H1···N10.891.812.6177 (15)151

Experimental details

Crystal data
Chemical formulaC29H26N2O4
Mr466.52
Crystal system, space groupMonoclinic, C2/c
Temperature (K)293
a, b, c (Å)41.307 (4), 4.5993 (3), 12.2229 (13)
β (°) 93.653 (12)
V (Å3)2317.4 (4)
Z4
Radiation typeMo Kα
µ (mm−1)0.09
Crystal size (mm)0.69 × 0.38 × 0.06
Data collection
DiffractometerStoe IPDS
Absorption correctionGaussian
(PLATON-ABSGAUSS; Spek, 2009)
Tmin, Tmax0.953, 0.993
No. of measured, independent and
observed [I > 2σ(I)] reflections		10694, 2244, 1662
Rint0.037
(sin θ/λ)max (Å−1)0.612
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.039, 0.116, 1.06
No. of reflections2244
No. of parameters160
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å−3)0.17, −0.15

Computer programs: EXPOSE (Stoe & Cie, 1995), X-RED (Stoe & Cie, 1995), SIR92 (Altomare et al., 1993), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 1997), publCIF (Westrip, 2010).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1—H1···N10.891.812.6177 (15)150.5
 

Acknowledgements

The authors are very grateful to Professor Jean-Claude Daran at the Laboratoire de Chimie de Coordination, UPR-CNRS 8241 (Toulouse) for his valuable contribution and insightful discussions.

References

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ISSN: 2056-9890
Volume 68| Part 4| April 2012| Page o1141
doi:10.1107/S1600536812010550
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