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Acta Crystallogr Sect E Struct Rep Online. 2010 January 1; 66(Pt 1): m77.
Published online 2009 December 19. doi:  10.1107/S1600536809053720
PMCID: PMC2980178

[5,5′-Dihydr­oxy-2,2′-[o-phenyl­enebis(nitrilo­methyl­idyne)]diphenolato}copper(II) methanol disolvate

Abstract

In the title compound, [Cu(C20H14N2O4)]·2CH3OH, the CuII ion is coordinated by two N [Cu—N = 1.933 (2) and 1.941 (2) Å] and two O [Cu—O = 1.890 (2) and 1.9038 (19) Å] atoms from the tetra­dentate Schiff base ligand 5,5′-dihydr­oxy-2,2′-[o-phenyl­enebis(nitrilo­methyl­idyne)]diphen­olate (L) in a distorted square-planar geometry. In the crystal, inter­molecular O—H(...)O hydrogen bonds link two CuL mol­ecules and four solvent mol­ecules into a centrosymmetric cluster. The crystal packing exhibits short inter­molecular C(...)C contacts of 3.185 (4) and 3.232 (4) Å.

Related literature

For related structures, see: Amirnasr et al. (2006 [triangle]); Arola-Arnal et al. (2008 [triangle]); Sundaravel et al. (2009 [triangle]); Lu et al. (2006 [triangle]).

An external file that holds a picture, illustration, etc.
Object name is e-66-00m77-scheme1.jpg

Experimental

Crystal data

  • [Cu(C20H14N2O4)]·2CH4O
  • M r = 473.96
  • Triclinic, An external file that holds a picture, illustration, etc.
Object name is e-66-00m77-efi1.jpg
  • a = 7.9520 (17) Å
  • b = 11.066 (2) Å
  • c = 11.870 (2) Å
  • α = 91.796 (2)°
  • β = 94.604 (3)°
  • γ = 94.241 (3)°
  • V = 1037.6 (4) Å3
  • Z = 2
  • Mo Kα radiation
  • μ = 1.10 mm−1
  • T = 293 K
  • 0.53 × 0.48 × 0.21 mm

Data collection

  • Bruker SMART 1000 CCD area-detector diffractometer
  • Absorption correction: multi-scan (SADABS; Sheldrick, 1996 [triangle]) T min = 0.595, T max = 0.803
  • 5360 measured reflections
  • 3592 independent reflections
  • 2873 reflections with I > 2σ(I)
  • R int = 0.027

Refinement

  • R[F 2 > 2σ(F 2)] = 0.037
  • wR(F 2) = 0.099
  • S = 1.00
  • 3592 reflections
  • 280 parameters
  • H-atom parameters constrained
  • Δρmax = 0.46 e Å−3
  • Δρmin = −0.36 e Å−3

Data collection: SMART (Siemens, 1996 [triangle]); cell refinement: SAINT (Siemens, 1996 [triangle]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 [triangle]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 [triangle]); molecular graphics: SHELXTL (Sheldrick, 2008 [triangle]); software used to prepare material for publication: SHELXTL.

Table 1
Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536809053720/cv2670sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536809053720/cv2670Isup2.hkl

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

Acknowledgments

We acknowledge the financial support of the National Natural Science Foundation of China (grant No. 20671048).

supplementary crystallographic information

Comment

Copper complexes have attracted intensive interest in the past decade because they play important roles on the fields of coordination chemistry, bioinorganic chemistry, redox enzyme systems and others (Amirnasr et al., 2006). In a continuation of a study of Schiff base ligands and their copper(II) complexes, we report here the title complex, (I).

In (I) (Fig. 1),the main plane being formed by the three phenyl and the N2O2. The angles O1—Cu1—N2 (178.64 (9)°) and O3—Cu1—N1 (178.39 (9)°) indicate that the coordination geometry of the copper atom is four-coordinate in an approximately square planar, which acts as a tetradentate ligand through its o-phenylenediamine N atoms and its deprotonated phenol O atoms. This square planar geometry is the most usual for CuII complexes (Arola-Arnal et al., 2008) in the N202 donor set with Schiff base ligands. The Cu—O distances of 1.9022 (19)Å and 1.889 (2)Å are very close to the corresponding values in related structures (1.904 (2)Å and 1.884 (3) Å; Sundaravel et al., 2009). The Cu—N distances of 1.932 (2)Å and 1.942 (2)Å are very close to the corresponding values in related structures(1.946 (2) Å; Lu et al., 2006). Intermolecular O—H···O hydrogen bonds (Table 1) link the molecules into a centrosymmetric cluster.

Experimental

o-Phenylenediamine(1 mmol, 108.22 mg) was dissolved in hot ethanol (20 ml) and added dropwise to a ethanol solution (10 ml) of 2,4-dihydroxybenzaldehyde (2 mmol, 276.2 mg). The mixture was then stirred at 323 K for 4 h. The triethylamine solution (3 ml) of Copper (II) acetate (1.5 mmol, 299.5 mg) was then added dropwise and the mixture stirred for another 5 h, at which point a red precipitate collected by suction filtration and washed with ethanol and ether. Crystals of the title compound suitable for X-ray analysis were from the methanol and dimethylformamide solution after about two weeks.

Refinement

All H atoms were placed geometrically and treated as riding on their parent atoms with C—H = 0.96 Å (methylene) or 0.93 Å (aromatic), 0.82 Å (hydroxyl) and Uiso(H) = 1.2-1.5Ueq of the parent atom.

Figures

Fig. 1.
The molecular structure of the title compound showing the atomic labels and 30% probability displacement ellipsoids.

Crystal data

[Cu(C20H14N2O4)]·2CH4OZ = 2
Mr = 473.96F(000) = 490
Triclinic, P1Dx = 1.517 Mg m3
a = 7.9520 (17) ÅMo Kα radiation, λ = 0.71073 Å
b = 11.066 (2) ÅCell parameters from 2490 reflections
c = 11.870 (2) Åθ = 2.5–26.4°
α = 91.796 (2)°µ = 1.10 mm1
β = 94.604 (3)°T = 293 K
γ = 94.241 (3)°Block, red
V = 1037.6 (4) Å30.53 × 0.48 × 0.21 mm

Data collection

Bruker SMART 1000 CCD area-detector diffractometer3592 independent reflections
Radiation source: fine-focus sealed tube2873 reflections with I > 2σ(I)
graphiteRint = 0.027
phi and ω scansθmax = 25.0°, θmin = 1.7°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)h = −9→9
Tmin = 0.595, Tmax = 0.803k = −12→13
5360 measured reflectionsl = −14→10

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)] = 0.037Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.099H-atom parameters constrained
S = 1.00w = 1/[σ2(Fo2) + (0.0446P)2 + 0.5623P] where P = (Fo2 + 2Fc2)/3
3592 reflections(Δ/σ)max < 0.001
280 parametersΔρmax = 0.46 e Å3
0 restraintsΔρmin = −0.36 e Å3

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2)

xyzUiso*/Ueq
Cu10.84950 (4)0.91865 (3)0.07516 (3)0.03348 (14)
N10.7711 (3)0.9467 (2)−0.07955 (19)0.0322 (5)
N20.9482 (3)0.7807 (2)0.00880 (19)0.0317 (5)
O10.7530 (2)1.05584 (16)0.13697 (16)0.0356 (5)
O20.4653 (3)1.41526 (18)0.14493 (19)0.0522 (6)
H20.49911.41420.21200.078*
O30.9320 (3)0.89012 (18)0.22501 (16)0.0433 (5)
O41.2805 (4)0.7377 (2)0.52128 (19)0.0724 (8)
H41.24740.79600.55510.109*
O50.6076 (4)0.4576 (2)0.3584 (2)0.0780 (8)
H50.64540.40100.39270.117*
O60.7454 (6)1.0573 (3)0.3705 (3)0.1286 (17)
H60.80501.04330.31910.193*
C10.8192 (4)0.8588 (3)−0.1582 (2)0.0374 (7)
C20.9139 (4)0.7681 (3)−0.1106 (3)0.0373 (7)
C30.9676 (4)0.6789 (3)−0.1807 (3)0.0455 (8)
H31.03140.6191−0.14980.055*
C40.9275 (5)0.6780 (3)−0.2961 (3)0.0581 (9)
H4A0.96240.6170−0.34250.070*
C50.8358 (6)0.7674 (3)−0.3423 (3)0.0670 (11)
H5A0.81010.7672−0.42010.080*
C60.7815 (5)0.8574 (3)−0.2742 (3)0.0561 (9)
H6A0.71930.9174−0.30630.067*
C70.6728 (4)1.0312 (3)−0.1095 (2)0.0351 (7)
H70.63401.0315−0.18550.042*
C80.6194 (3)1.1225 (2)−0.0376 (2)0.0318 (6)
C90.6652 (3)1.1344 (2)0.0815 (2)0.0314 (6)
C100.6127 (4)1.2337 (2)0.1415 (3)0.0366 (7)
H100.64301.24310.21880.044*
C110.5170 (4)1.3183 (3)0.0890 (3)0.0378 (7)
C120.4682 (4)1.3056 (3)−0.0271 (3)0.0436 (8)
H120.40221.3618−0.06240.052*
C130.5181 (4)1.2108 (3)−0.0873 (3)0.0395 (7)
H130.48491.2029−0.16430.047*
C141.0398 (4)0.7072 (2)0.0662 (2)0.0357 (7)
H141.07920.64320.02590.043*
C151.0849 (4)0.7158 (2)0.1845 (2)0.0361 (7)
C161.0355 (4)0.8091 (2)0.2577 (2)0.0356 (7)
C171.1031 (4)0.8149 (3)0.3713 (3)0.0444 (8)
H171.07410.87610.41980.053*
C181.2108 (4)0.7320 (3)0.4118 (3)0.0487 (8)
C191.2564 (4)0.6381 (3)0.3410 (3)0.0500 (8)
H191.32790.58130.36900.060*
C201.1945 (4)0.6318 (3)0.2312 (3)0.0438 (8)
H201.22530.56960.18440.053*
C210.7229 (7)0.5589 (4)0.3737 (5)0.1056 (17)
H21A0.70130.60450.44040.158*
H21B0.71100.60870.30920.158*
H21C0.83580.53320.38200.158*
C220.6689 (6)0.9506 (5)0.4033 (4)0.0857 (14)
H22A0.67130.95130.48430.129*
H22B0.72820.88400.37720.129*
H22C0.55370.94180.37140.129*

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
Cu10.0365 (2)0.0294 (2)0.0349 (2)0.00663 (14)0.00252 (14)−0.00080 (14)
N10.0339 (13)0.0275 (12)0.0353 (13)0.0012 (10)0.0054 (10)−0.0027 (10)
N20.0280 (12)0.0304 (12)0.0360 (13)−0.0005 (10)0.0034 (10)−0.0040 (10)
O10.0411 (11)0.0303 (10)0.0356 (11)0.0106 (9)−0.0022 (9)0.0002 (8)
O20.0675 (15)0.0326 (12)0.0578 (14)0.0219 (11)−0.0016 (11)−0.0014 (10)
O30.0554 (14)0.0415 (12)0.0356 (11)0.0245 (10)0.0028 (10)−0.0013 (9)
O40.111 (2)0.0646 (17)0.0450 (14)0.0490 (16)−0.0096 (14)0.0024 (12)
O50.113 (2)0.0505 (16)0.0681 (17)0.0266 (16)−0.0249 (16)−0.0026 (13)
O60.272 (5)0.072 (2)0.0547 (19)0.053 (3)0.061 (3)−0.0016 (16)
C10.0372 (16)0.0361 (16)0.0380 (17)−0.0040 (13)0.0053 (13)−0.0033 (13)
C20.0354 (16)0.0331 (15)0.0423 (17)−0.0042 (13)0.0070 (13)−0.0082 (13)
C30.0447 (19)0.0407 (18)0.050 (2)0.0028 (14)0.0047 (15)−0.0109 (15)
C40.073 (3)0.051 (2)0.051 (2)0.0060 (18)0.0110 (18)−0.0194 (17)
C50.101 (3)0.065 (2)0.0360 (19)0.018 (2)0.0022 (19)−0.0094 (17)
C60.080 (3)0.050 (2)0.0397 (19)0.0174 (18)0.0036 (17)−0.0033 (16)
C70.0366 (16)0.0346 (16)0.0330 (16)−0.0040 (13)0.0020 (13)0.0027 (13)
C80.0290 (15)0.0286 (14)0.0373 (16)−0.0023 (12)0.0026 (12)0.0047 (12)
C90.0265 (14)0.0266 (14)0.0402 (16)−0.0030 (11)0.0006 (12)0.0020 (12)
C100.0374 (17)0.0301 (15)0.0416 (17)0.0024 (12)−0.0008 (13)0.0009 (13)
C110.0348 (16)0.0283 (15)0.0498 (18)0.0011 (12)0.0006 (14)0.0046 (13)
C120.0433 (18)0.0337 (16)0.055 (2)0.0091 (14)0.0009 (15)0.0154 (15)
C130.0403 (17)0.0387 (17)0.0388 (16)−0.0007 (14)−0.0011 (13)0.0100 (14)
C140.0351 (16)0.0257 (14)0.0468 (18)0.0017 (12)0.0097 (13)−0.0053 (13)
C150.0395 (17)0.0271 (15)0.0429 (17)0.0043 (12)0.0090 (13)0.0015 (13)
C160.0384 (17)0.0306 (15)0.0394 (16)0.0071 (13)0.0079 (13)0.0042 (13)
C170.058 (2)0.0395 (17)0.0384 (17)0.0193 (15)0.0086 (15)0.0000 (14)
C180.060 (2)0.0445 (18)0.0445 (19)0.0187 (16)0.0029 (16)0.0093 (15)
C190.062 (2)0.0371 (17)0.055 (2)0.0244 (16)0.0060 (17)0.0118 (15)
C200.052 (2)0.0307 (16)0.0510 (19)0.0140 (14)0.0117 (16)0.0022 (14)
C210.113 (4)0.073 (3)0.125 (4)0.007 (3)−0.021 (3)−0.008 (3)
C220.093 (3)0.116 (4)0.055 (3)0.039 (3)0.016 (2)0.007 (3)

Geometric parameters (Å, °)

Cu1—O31.890 (2)C7—C81.412 (4)
Cu1—O11.9038 (19)C7—H70.9300
Cu1—N11.933 (2)C8—C131.425 (4)
Cu1—N21.941 (2)C8—C91.430 (4)
N1—C71.303 (4)C9—C101.398 (4)
N1—C11.421 (4)C10—C111.382 (4)
N2—C141.303 (3)C10—H100.9300
N2—C21.422 (4)C11—C121.401 (4)
O1—C91.315 (3)C12—C131.352 (4)
O2—C111.351 (4)C12—H120.9300
O2—H20.8200C13—H130.9300
O3—C161.308 (3)C14—C151.420 (4)
O4—C181.368 (4)C14—H140.9300
O4—H40.8200C15—C201.416 (4)
O5—C211.392 (5)C15—C161.426 (4)
O5—H50.8200C16—C171.408 (4)
O6—C221.369 (6)C17—C181.373 (4)
O6—H60.8200C17—H170.9300
C1—C61.385 (4)C18—C191.402 (4)
C1—C21.405 (4)C19—C201.354 (5)
C2—C31.385 (4)C19—H190.9300
C3—C41.381 (5)C20—H200.9300
C3—H30.9300C21—H21A0.9600
C4—C51.374 (5)C21—H21B0.9600
C4—H4A0.9300C21—H21C0.9600
C5—C61.378 (5)C22—H22A0.9600
C5—H5A0.9300C22—H22B0.9600
C6—H6A0.9300C22—H22C0.9600
C7···C9i3.185 (4)C8···C14ii3.232 (4)
O3—Cu1—O186.42 (8)C11—C10—C9121.7 (3)
O3—Cu1—N1178.39 (9)C11—C10—H10119.2
O1—Cu1—N194.78 (9)C9—C10—H10119.2
O3—Cu1—N294.77 (9)O2—C11—C10122.8 (3)
O1—Cu1—N2178.65 (9)O2—C11—C12116.9 (3)
N1—Cu1—N284.02 (9)C10—C11—C12120.3 (3)
C7—N1—C1122.4 (2)C13—C12—C11119.2 (3)
C7—N1—Cu1124.2 (2)C13—C12—H12120.4
C1—N1—Cu1113.23 (18)C11—C12—H12120.4
C14—N2—C2122.5 (2)C12—C13—C8122.7 (3)
C14—N2—Cu1124.2 (2)C12—C13—H13118.7
C2—N2—Cu1113.32 (18)C8—C13—H13118.7
C9—O1—Cu1127.17 (18)N2—C14—C15126.1 (3)
C11—O2—H2109.5N2—C14—H14117.0
C16—O3—Cu1127.11 (18)C15—C14—H14117.0
C18—O4—H4109.5C20—C15—C14118.0 (3)
C21—O5—H5109.5C20—C15—C16118.1 (3)
C22—O6—H6109.5C14—C15—C16123.7 (3)
C6—C1—C2119.5 (3)O3—C16—C17118.3 (3)
C6—C1—N1125.5 (3)O3—C16—C15123.7 (3)
C2—C1—N1115.1 (2)C17—C16—C15118.1 (3)
C3—C2—C1119.2 (3)C18—C17—C16121.4 (3)
C3—C2—N2126.4 (3)C18—C17—H17119.3
C1—C2—N2114.4 (2)C16—C17—H17119.3
C4—C3—C2120.7 (3)O4—C18—C17122.2 (3)
C4—C3—H3119.7O4—C18—C19117.1 (3)
C2—C3—H3119.7C17—C18—C19120.7 (3)
C5—C4—C3119.8 (3)C20—C19—C18118.8 (3)
C5—C4—H4A120.1C20—C19—H19120.6
C3—C4—H4A120.1C18—C19—H19120.6
C4—C5—C6120.5 (3)C19—C20—C15122.8 (3)
C4—C5—H5A119.7C19—C20—H20118.6
C6—C5—H5A119.7C15—C20—H20118.6
C5—C6—C1120.3 (3)O5—C21—H21A109.5
C5—C6—H6A119.9O5—C21—H21B109.5
C1—C6—H6A119.9H21A—C21—H21B109.5
N1—C7—C8126.3 (3)O5—C21—H21C109.5
N1—C7—H7116.9H21A—C21—H21C109.5
C8—C7—H7116.9H21B—C21—H21C109.5
C7—C8—C13118.0 (3)O6—C22—H22A109.5
C7—C8—C9124.3 (3)O6—C22—H22B109.5
C13—C8—C9117.7 (3)H22A—C22—H22B109.5
O1—C9—C10118.7 (3)O6—C22—H22C109.5
O1—C9—C8123.0 (3)H22A—C22—H22C109.5
C10—C9—C8118.4 (2)H22B—C22—H22C109.5
O3—Cu1—N1—C7−144 (3)Cu1—N1—C7—C86.1 (4)
O1—Cu1—N1—C7−5.2 (2)N1—C7—C8—C13177.0 (3)
N2—Cu1—N1—C7175.4 (2)N1—C7—C8—C9−0.8 (4)
O3—Cu1—N1—C142 (3)Cu1—O1—C9—C10−176.41 (18)
O1—Cu1—N1—C1−179.98 (18)Cu1—O1—C9—C84.1 (4)
N2—Cu1—N1—C10.65 (18)C7—C8—C9—O1−4.7 (4)
O3—Cu1—N2—C14−1.3 (2)C13—C8—C9—O1177.5 (2)
O1—Cu1—N2—C14150 (4)C7—C8—C9—C10175.8 (3)
N1—Cu1—N2—C14177.7 (2)C13—C8—C9—C10−2.0 (4)
O3—Cu1—N2—C2179.91 (18)O1—C9—C10—C11−178.6 (2)
O1—Cu1—N2—C2−28 (4)C8—C9—C10—C110.9 (4)
N1—Cu1—N2—C2−1.15 (18)C9—C10—C11—O2−179.7 (3)
O3—Cu1—O1—C9179.2 (2)C9—C10—C11—C120.7 (4)
N1—Cu1—O1—C90.3 (2)O2—C11—C12—C13179.3 (3)
N2—Cu1—O1—C927 (4)C10—C11—C12—C13−1.0 (4)
O1—Cu1—O3—C16−172.9 (2)C11—C12—C13—C8−0.2 (5)
N1—Cu1—O3—C16−34 (3)C7—C8—C13—C12−176.3 (3)
N2—Cu1—O3—C166.5 (2)C9—C8—C13—C121.7 (4)
C7—N1—C1—C65.7 (5)C2—N2—C14—C15177.7 (3)
Cu1—N1—C1—C6−179.4 (3)Cu1—N2—C14—C15−1.1 (4)
C7—N1—C1—C2−174.9 (2)N2—C14—C15—C20−176.1 (3)
Cu1—N1—C1—C20.0 (3)N2—C14—C15—C16−0.5 (5)
C6—C1—C2—C3−0.1 (4)Cu1—O3—C16—C17170.0 (2)
N1—C1—C2—C3−179.5 (2)Cu1—O3—C16—C15−9.4 (4)
C6—C1—C2—N2178.5 (3)C20—C15—C16—O3−178.4 (3)
N1—C1—C2—N2−0.9 (4)C14—C15—C16—O36.0 (5)
C14—N2—C2—C31.0 (4)C20—C15—C16—C172.1 (4)
Cu1—N2—C2—C3179.9 (2)C14—C15—C16—C17−173.5 (3)
C14—N2—C2—C1−177.4 (2)O3—C16—C17—C18179.2 (3)
Cu1—N2—C2—C11.4 (3)C15—C16—C17—C18−1.3 (5)
C1—C2—C3—C4−0.7 (5)C16—C17—C18—O4178.6 (3)
N2—C2—C3—C4−179.0 (3)C16—C17—C18—C19−0.3 (5)
C2—C3—C4—C51.1 (5)O4—C18—C19—C20−177.8 (3)
C3—C4—C5—C6−0.9 (6)C17—C18—C19—C201.1 (5)
C4—C5—C6—C10.1 (6)C18—C19—C20—C15−0.2 (5)
C2—C1—C6—C50.3 (5)C14—C15—C20—C19174.4 (3)
N1—C1—C6—C5179.7 (3)C16—C15—C20—C19−1.4 (5)
C1—N1—C7—C8−179.6 (2)

Symmetry codes: (i) −x+1, −y+2, −z; (ii) −x+2, −y+2, −z.

Hydrogen-bond geometry (Å, °)

D—H···AD—HH···AD···AD—H···A
O2—H2···O5iii0.821.912.704 (3)163
O4—H4···O6iv0.821.822.602 (4)159
O5—H5···O4v0.821.972.788 (3)176
O6—H6···O10.822.182.777 (3)130
O6—H6···O30.822.343.037 (4)144

Symmetry codes: (iii) x, y+1, z; (iv) −x+2, −y+2, −z+1; (v) −x+2, −y+1, −z+1.

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: CV2670).

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