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Acta Crystallogr Sect E Struct Rep Online. 2010 March 1; 66(Pt 3): o539.
Published online 2010 February 6. doi:  10.1107/S1600536810002916
PMCID: PMC2983671

6,6′-Dimeth­oxy-2,2′-[4,5-dimethyl-o-phenyl­enebis(nitrilo­methyl­idyne)]diphenol monohydrate

Abstract

In the title compound, C24H24N2O4·H2O, the dihedral angles between the central benzene ring and the two outer benzene rings of the Schiff base are 65.06 (9) and 3.02 (9)°. Strong intra­molecular O—H(...)N hydrogen bonds generate S(6) ring motifs. The H atoms of the water mol­ecule act as donors in the formation of bifurcated O—H(...)(O,O) inter­molecular hydrogen bonds with the O atoms of the hydr­oxy and meth­oxy groups with R 1 2(5) ring motifs; these may influence the mol­ecular conformation.

Related literature

For bond-length data, see: Allen et al. (1987 [triangle]). For hydrogen-bond motifs, see: Bernstein et al. (1995 [triangle]). For related structures, see: Cakir et al. (2002 [triangle]); Eltayeb & Ahmed (2005 [triangle]); Eltayeb et al. (2007 [triangle]); Kargar et al. (2009 [triangle]). For background to the applications of Schiff base ligands as thermochromic and photochromic materials, see: Hajioudis et al. (1987 [triangle]).

An external file that holds a picture, illustration, etc.
Object name is e-66-0o539-scheme1.jpg

Experimental

Crystal data

  • C24H24N2O4·H2O
  • M r = 422.47
  • Triclinic, An external file that holds a picture, illustration, etc.
Object name is e-66-0o539-efi1.jpg
  • a = 8.7431 (5) Å
  • b = 10.3049 (6) Å
  • c = 13.6614 (7) Å
  • α = 69.556 (3)°
  • β = 83.846 (3)°
  • γ = 70.280 (3)°
  • V = 1085.6 (1) Å3
  • Z = 2
  • Mo Kα radiation
  • μ = 0.09 mm−1
  • T = 296 K
  • 0.30 × 0.20 × 0.15 mm

Data collection

  • Bruker SMART APEXII CCD area-detector diffractometer
  • Absorption correction: multi-scan (SADABS; Bruker, 2005 [triangle]) T min = 0.973, T max = 0.987
  • 23270 measured reflections
  • 5369 independent reflections
  • 2912 reflections with I > 2I)
  • R int = 0.031

Refinement

  • R[F 2 > 2σ(F 2)] = 0.046
  • wR(F 2) = 0.141
  • S = 1.01
  • 5369 reflections
  • 284 parameters
  • H-atom parameters constrained
  • Δρmax = 0.20 e Å−3
  • Δρmin = −0.18 e Å−3

Data collection: APEX2 (Bruker, 2005 [triangle]); cell refinement: SAINT (Bruker, 2005 [triangle]); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008 [triangle]); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL and PLATON (Spek, 2009 [triangle]).

Table 1
Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536810002916/lh2982sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536810002916/lh2982Isup2.hkl

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Acknowledgments

HK and AJ thank PNU for financial support. IUK thanks GC University of Lahore, Pakistan, for the research facilities.

supplementary crystallographic information

Comment

Schiff base ligands are one of the most prevalent systems in coordination chemistry. They can show thermochromic and photochromic properties (Hajioudis et al. (1987). As part of a general study of tetradenate Schiff bases (Kargar et al. 2009), we have determined the crystal structure of the title compound.

The asymmetric unit of the title compound, Fig. 1, comprises a Schiff base ligand and a water molecule of crystallization. The bond lengths (Allen et al., 1987) and angles are within the normal ranges and comparable to previously reported structures (Eltayeb & Ahmed, 2005; Eltayeb et al., 2007; Cakir et al. 2002; Kargar et al., 2009 ). The dihedral angles between the central benzene ring and the two outer benzene rings of the Schiff base are 65.06 (9) and 3.02 (9)°. Strong intramolecular O—H···N hydrogen bonds generate S(6) ring motifs (Bernstein et al., 1995). The hydrogen atoms of the water molecule form bifurcated intermolecular hydrogen bonds with the oxygen atoms of the hydroxy and methoxy groups with R21(5) ring motifs (Bernstein et al., 1995), which may, in part, influence the molecular configuration (Table 1). A view of part of the crystal structure is shown in Fig .2.

Experimental

The title compound was synthesized by adding 3-methoxy-salicylaldehyde (4 mmol) to a solution of 4,5-dimethyl-o-phenylenediamine (2 mmol) in ethanol (20 ml). The mixture was refluxed with stirring for half an hour. The resultant yellow solution was filtered. Yellow single crystals of the title compound suitable for X-ray structure determination were recrystallized from ethanol by slow evaporation of the solvents at room temperature over several days.

Refinement

H atoms of the hydroxy groups of the Schiff base and water were located in a difference Fourier map. Initially the O-H distances were restrained to 0.96 (1) and 0.98 (1) Å, respectively and in the final cycles of refinement these H atoms were allowed to ride on the parent O atom with Uiso(H) = 1.5 Ueq(O), see Table 1. The remaining H atoms were positioned geometrically with C-H = 0.93-0.96 Å and included in a riding model approximation with Uiso (H) = 1.2 or 1.5 Ueq (C). A rotating group model was used for the methyl groups.

Figures

Fig. 1.
The asymmetric unit of the title compound, showing 30% probability displacement ellipsoids and the atomic numbering. Intra- and intermolecular hydrogen bonds are drawn as dashed lines.
Fig. 2.
The crystal packing of the title compound wieved along the a-axis. Hydrogen bonds are shown as dashed lines.

Crystal data

C24H24N2O4·H2OZ = 2
Mr = 422.47F(000) = 448
Triclinic, P1Dx = 1.292 Mg m3
Hall symbol: -P 1Mo Kα radiation, λ = 0.71073 Å
a = 8.7431 (5) ÅCell parameters from 5124 reflections
b = 10.3049 (6) Åθ = 2.2–25.0°
c = 13.6614 (7) ŵ = 0.09 mm1
α = 69.556 (3)°T = 296 K
β = 83.846 (3)°Block, yellow
γ = 70.280 (3)°0.30 × 0.20 × 0.15 mm
V = 1085.6 (1) Å3

Data collection

Bruker SMART APEXII CCD area-detector diffractometer5369 independent reflections
Radiation source: fine-focus sealed tube2912 reflections with I > 2˘I)
graphiteRint = 0.031
[var phi] and ω scansθmax = 28.3°, θmin = 2.2°
Absorption correction: multi-scan (SADABS; Bruker, 2005)h = −11→11
Tmin = 0.973, Tmax = 0.987k = −12→13
23270 measured reflectionsl = −18→18

Refinement

Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.046Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.141H-atom parameters constrained
S = 1.00w = 1/[σ2(Fo2) + (0.0622P)2 + 0.1326P] where P = (Fo2 + 2Fc2)/3
5369 reflections(Δ/σ)max < 0.001
284 parametersΔρmax = 0.20 e Å3
0 restraintsΔρmin = −0.18 e Å3

Special details

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 > 2sigma(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)

xyzUiso*/Ueq
O10.48196 (13)0.46281 (13)0.27727 (9)0.0574 (3)
H10.55310.40270.33620.086*
O20.58907 (14)0.10375 (12)0.31399 (9)0.0563 (3)
H20.64630.11020.36780.084*
O30.34071 (17)0.62867 (15)0.09838 (10)0.0749 (4)
O40.45471 (16)0.01221 (14)0.20011 (10)0.0692 (4)
N10.74540 (15)0.32782 (13)0.39027 (10)0.0436 (3)
N20.74691 (15)0.04912 (14)0.47979 (10)0.0438 (3)
C10.5789 (2)0.51020 (17)0.19880 (12)0.0465 (4)
C20.5055 (2)0.59934 (18)0.10105 (13)0.0549 (5)
C30.5987 (3)0.6496 (2)0.01908 (14)0.0687 (6)
H3A0.55020.7081−0.04590.082*
C40.7642 (3)0.6143 (2)0.03171 (15)0.0733 (6)
H4A0.82620.6484−0.02490.088*
C50.8378 (2)0.5294 (2)0.12719 (14)0.0630 (5)
H5A0.94890.50760.13540.076*
C60.7458 (2)0.47583 (17)0.21197 (12)0.0469 (4)
C70.8237 (2)0.38539 (17)0.31301 (13)0.0466 (4)
H7A0.93350.36920.32140.056*
C80.82177 (17)0.24595 (16)0.48957 (11)0.0401 (4)
C90.88484 (19)0.30867 (18)0.54329 (13)0.0475 (4)
H9A0.88440.40460.51100.057*
C100.94858 (19)0.2329 (2)0.64369 (13)0.0496 (4)
C110.95310 (19)0.0878 (2)0.69018 (12)0.0507 (4)
C120.88856 (19)0.02546 (18)0.63693 (12)0.0493 (4)
H12A0.8914−0.07120.66850.059*
C130.81949 (17)0.10333 (17)0.53748 (12)0.0410 (4)
C140.74023 (18)−0.08139 (17)0.51154 (13)0.0467 (4)
H14A0.7864−0.14590.57590.056*
C150.66348 (18)−0.13050 (17)0.45037 (13)0.0455 (4)
C160.6581 (2)−0.27411 (18)0.48757 (15)0.0563 (5)
H16A0.7039−0.33700.55240.068*
C170.5870 (2)−0.32238 (19)0.43002 (16)0.0605 (5)
H17A0.5842−0.41790.45560.073*
C180.5181 (2)−0.2296 (2)0.33301 (16)0.0589 (5)
H18A0.4699−0.26370.29400.071*
C190.5206 (2)−0.08833 (19)0.29418 (14)0.0517 (4)
C200.59181 (18)−0.03598 (17)0.35303 (13)0.0458 (4)
C210.2574 (3)0.7227 (2)0.00270 (16)0.0918 (8)
H21A0.14380.73350.01060.138*
H21B0.30060.6814−0.05140.138*
H21C0.27150.8168−0.01570.138*
C220.4007 (3)−0.0392 (3)0.13155 (17)0.0840 (7)
H22A0.35460.04120.06970.126*
H22B0.3198−0.08340.16540.126*
H22C0.4908−0.11040.11290.126*
C231.0072 (2)0.3092 (2)0.70012 (15)0.0693 (6)
H23A0.99460.40770.65540.104*
H23B1.11980.25800.71880.104*
H23C0.94470.31060.76220.104*
C241.0284 (2)−0.0036 (3)0.79731 (14)0.0789 (7)
H24A0.97680.04470.84660.118*
H24B1.1423−0.01570.79500.118*
H24C1.0137−0.09770.81830.118*
O1W0.25045 (16)0.32247 (16)0.23580 (10)0.0795 (4)
H1W0.29530.40120.22380.119*
H2W0.35470.24630.24670.119*

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
O10.0557 (7)0.0600 (8)0.0444 (7)−0.0177 (6)−0.0123 (6)−0.0001 (6)
O20.0718 (8)0.0398 (7)0.0541 (7)−0.0176 (6)−0.0099 (6)−0.0094 (5)
O30.0744 (9)0.0733 (9)0.0556 (8)−0.0061 (7)−0.0298 (7)−0.0043 (7)
O40.0853 (9)0.0595 (8)0.0662 (9)−0.0225 (7)−0.0143 (7)−0.0214 (7)
N10.0496 (8)0.0390 (7)0.0354 (7)−0.0115 (6)−0.0089 (6)−0.0044 (6)
N20.0436 (7)0.0394 (8)0.0416 (8)−0.0102 (6)0.0013 (6)−0.0088 (6)
C10.0625 (10)0.0373 (9)0.0362 (9)−0.0140 (8)−0.0068 (8)−0.0078 (7)
C20.0712 (12)0.0433 (10)0.0424 (10)−0.0082 (9)−0.0148 (9)−0.0104 (8)
C30.1010 (17)0.0537 (12)0.0371 (10)−0.0130 (11)−0.0127 (10)−0.0058 (9)
C40.0947 (17)0.0735 (14)0.0409 (11)−0.0281 (12)0.0079 (10)−0.0076 (10)
C50.0733 (12)0.0650 (12)0.0466 (11)−0.0248 (10)0.0049 (9)−0.0125 (9)
C60.0592 (10)0.0412 (9)0.0377 (9)−0.0143 (8)−0.0039 (8)−0.0108 (7)
C70.0499 (9)0.0434 (9)0.0439 (10)−0.0111 (8)−0.0065 (8)−0.0130 (8)
C80.0354 (8)0.0404 (9)0.0347 (8)−0.0052 (6)−0.0040 (6)−0.0064 (7)
C90.0458 (9)0.0467 (10)0.0458 (10)−0.0111 (7)−0.0050 (7)−0.0125 (8)
C100.0394 (9)0.0627 (11)0.0426 (9)−0.0089 (8)−0.0027 (7)−0.0192 (9)
C110.0405 (9)0.0648 (12)0.0348 (9)−0.0055 (8)−0.0033 (7)−0.0123 (8)
C120.0457 (9)0.0437 (9)0.0400 (9)−0.0032 (7)−0.0007 (7)−0.0026 (7)
C130.0352 (8)0.0433 (9)0.0363 (8)−0.0057 (7)−0.0001 (6)−0.0099 (7)
C140.0420 (9)0.0428 (10)0.0437 (9)−0.0084 (7)0.0034 (7)−0.0064 (8)
C150.0383 (8)0.0391 (9)0.0527 (10)−0.0088 (7)0.0081 (7)−0.0132 (8)
C160.0506 (10)0.0421 (10)0.0660 (12)−0.0133 (8)0.0086 (9)−0.0099 (9)
C170.0549 (11)0.0407 (10)0.0834 (14)−0.0200 (8)0.0131 (10)−0.0169 (10)
C180.0511 (10)0.0542 (11)0.0801 (14)−0.0199 (9)0.0106 (10)−0.0329 (11)
C190.0472 (9)0.0464 (10)0.0590 (11)−0.0115 (8)0.0041 (8)−0.0190 (9)
C200.0415 (9)0.0387 (9)0.0554 (10)−0.0116 (7)0.0079 (8)−0.0171 (8)
C210.1047 (17)0.0766 (15)0.0687 (14)0.0037 (13)−0.0514 (13)−0.0104 (12)
C220.1109 (18)0.0963 (17)0.0642 (14)−0.0490 (14)0.0015 (12)−0.0350 (13)
C230.0644 (12)0.0936 (16)0.0568 (12)−0.0233 (11)−0.0064 (9)−0.0333 (11)
C240.0728 (13)0.0990 (17)0.0419 (11)−0.0162 (12)−0.0161 (9)−0.0021 (11)
O1W0.0693 (9)0.0887 (11)0.0677 (9)−0.0254 (8)−0.0075 (7)−0.0086 (8)

Geometric parameters (Å, °)

O1—C11.3511 (19)C11—C121.385 (2)
O1—H10.9574C11—C241.512 (2)
O2—C201.3422 (18)C12—C131.394 (2)
O2—H20.9642C12—H12A0.9300
O3—C21.371 (2)C14—C151.432 (2)
O3—C211.422 (2)C14—H14A0.9300
O4—C191.372 (2)C15—C161.402 (2)
O4—C221.411 (2)C15—C201.404 (2)
N1—C71.271 (2)C16—C171.356 (3)
N1—C81.4186 (18)C16—H16A0.9300
N2—C141.281 (2)C17—C181.389 (3)
N2—C131.411 (2)C17—H17A0.9300
C1—C61.396 (2)C18—C191.372 (2)
C1—C21.403 (2)C18—H18A0.9300
C2—C31.367 (3)C19—C201.401 (2)
C3—C41.382 (3)C21—H21A0.9600
C3—H3A0.9300C21—H21B0.9600
C4—C51.373 (3)C21—H21C0.9600
C4—H4A0.9300C22—H22A0.9600
C5—C61.395 (2)C22—H22B0.9600
C5—H5A0.9300C22—H22C0.9600
C6—C71.453 (2)C23—H23A0.9600
C7—H7A0.9300C23—H23B0.9600
C8—C91.385 (2)C23—H23C0.9600
C8—C131.391 (2)C24—H24A0.9600
C9—C101.387 (2)C24—H24B0.9600
C9—H9A0.9300C24—H24C0.9600
C10—C111.394 (2)O1W—H1W0.9731
C10—C231.502 (2)O1W—H2W0.9664
C1—O1—H1105.3N2—C14—H14A119.2
C20—O2—H2101.6C15—C14—H14A119.2
C2—O3—C21117.48 (16)C16—C15—C20119.09 (16)
C19—O4—C22117.25 (15)C16—C15—C14120.16 (16)
C7—N1—C8120.70 (13)C20—C15—C14120.75 (15)
C14—N2—C13123.85 (14)C17—C16—C15120.75 (17)
O1—C1—C6122.82 (14)C17—C16—H16A119.6
O1—C1—C2117.44 (16)C15—C16—H16A119.6
C6—C1—C2119.74 (16)C16—C17—C18120.21 (17)
C3—C2—O3125.95 (16)C16—C17—H17A119.9
C3—C2—C1119.61 (18)C18—C17—H17A119.9
O3—C2—C1114.44 (16)C19—C18—C17120.71 (18)
C2—C3—C4120.71 (17)C19—C18—H18A119.6
C2—C3—H3A119.6C17—C18—H18A119.6
C4—C3—H3A119.6C18—C19—O4125.26 (17)
C5—C4—C3120.52 (19)C18—C19—C20119.90 (17)
C5—C4—H4A119.7O4—C19—C20114.83 (15)
C3—C4—H4A119.7O2—C20—C19118.51 (15)
C4—C5—C6119.97 (19)O2—C20—C15122.17 (15)
C4—C5—H5A120.0C19—C20—C15119.32 (15)
C6—C5—H5A120.0O3—C21—H21A109.5
C5—C6—C1119.44 (15)O3—C21—H21B109.5
C5—C6—C7120.03 (16)H21A—C21—H21B109.5
C1—C6—C7120.54 (15)O3—C21—H21C109.5
N1—C7—C6121.65 (15)H21A—C21—H21C109.5
N1—C7—H7A119.2H21B—C21—H21C109.5
C6—C7—H7A119.2O4—C22—H22A109.5
C9—C8—C13119.56 (14)O4—C22—H22B109.5
C9—C8—N1121.60 (14)H22A—C22—H22B109.5
C13—C8—N1118.58 (14)O4—C22—H22C109.5
C8—C9—C10122.06 (16)H22A—C22—H22C109.5
C8—C9—H9A119.0H22B—C22—H22C109.5
C10—C9—H9A119.0C10—C23—H23A109.5
C9—C10—C11118.54 (16)C10—C23—H23B109.5
C9—C10—C23119.63 (17)H23A—C23—H23B109.5
C11—C10—C23121.82 (15)C10—C23—H23C109.5
C12—C11—C10119.41 (14)H23A—C23—H23C109.5
C12—C11—C24119.24 (17)H23B—C23—H23C109.5
C10—C11—C24121.35 (17)C11—C24—H24A109.5
C11—C12—C13121.97 (16)C11—C24—H24B109.5
C11—C12—H12A119.0H24A—C24—H24B109.5
C13—C12—H12A119.0C11—C24—H24C109.5
C8—C13—C12118.37 (15)H24A—C24—H24C109.5
C8—C13—N2116.34 (13)H24B—C24—H24C109.5
C12—C13—N2125.28 (15)H1W—O1W—H2W95.0
N2—C14—C15121.63 (15)
C21—O3—C2—C3−1.7 (3)C10—C11—C12—C130.3 (2)
C21—O3—C2—C1177.79 (17)C24—C11—C12—C13−179.15 (15)
O1—C1—C2—C3−179.75 (16)C9—C8—C13—C12−3.1 (2)
C6—C1—C2—C31.2 (3)N1—C8—C13—C12−177.31 (14)
O1—C1—C2—O30.7 (2)C9—C8—C13—N2177.27 (13)
C6—C1—C2—O3−178.33 (15)N1—C8—C13—N23.0 (2)
O3—C2—C3—C4178.97 (18)C11—C12—C13—C82.5 (2)
C1—C2—C3—C4−0.5 (3)C11—C12—C13—N2−177.89 (14)
C2—C3—C4—C5−0.7 (3)C14—N2—C13—C8177.54 (14)
C3—C4—C5—C61.1 (3)C14—N2—C13—C12−2.1 (2)
C4—C5—C6—C1−0.4 (3)C13—N2—C14—C15179.30 (14)
C4—C5—C6—C7179.75 (18)N2—C14—C15—C16−179.90 (15)
O1—C1—C6—C5−179.76 (16)N2—C14—C15—C20−0.3 (2)
C2—C1—C6—C5−0.7 (2)C20—C15—C16—C171.0 (2)
O1—C1—C6—C70.1 (2)C14—C15—C16—C17−179.45 (16)
C2—C1—C6—C7179.11 (15)C15—C16—C17—C180.0 (3)
C8—N1—C7—C6−176.84 (14)C16—C17—C18—C19−0.2 (3)
C5—C6—C7—N1−175.85 (16)C17—C18—C19—O4−179.23 (16)
C1—C6—C7—N14.3 (2)C17—C18—C19—C20−0.6 (3)
C7—N1—C8—C961.2 (2)C22—O4—C19—C18−9.5 (3)
C7—N1—C8—C13−124.72 (17)C22—O4—C19—C20171.84 (16)
C13—C8—C9—C100.9 (2)C18—C19—C20—O2−178.50 (15)
N1—C8—C9—C10174.99 (14)O4—C19—C20—O20.3 (2)
C8—C9—C10—C111.9 (2)C18—C19—C20—C151.5 (2)
C8—C9—C10—C23−176.79 (15)O4—C19—C20—C15−179.69 (14)
C9—C10—C11—C12−2.5 (2)C16—C15—C20—O2178.33 (14)
C23—C10—C11—C12176.17 (15)C14—C15—C20—O2−1.3 (2)
C9—C10—C11—C24176.97 (16)C16—C15—C20—C19−1.7 (2)
C23—C10—C11—C24−4.4 (3)C14—C15—C20—C19178.70 (15)

Hydrogen-bond geometry (Å, °)

D—H···AD—HH···AD···AD—H···A
O1—H1···N10.961.722.5929 (18)150
O1W—H1W···O10.972.213.050 (2)144
O1W—H1W···O30.972.503.366 (2)148
O2—H2···N20.961.662.5704 (18)156
O1W—H2W···O20.972.153.079 (2)160
O1W—H2W···O40.972.553.271 (2)131

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: LH2982).

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