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Acta Cryst. (2011). E67, m779    [ doi:10.1107/S1600536811018162 ]

Bis(2-methylbenzoato-[kappa]2O,O')(1,10'-phenanthroline-[kappa]2N,N')copper(II)

S.-L. Ni, F. Zhou and J.-L. Qi

Abstract top

In the title compound, [Cu(C8H7O2)2(C12H8N2)], the CuII atom assumes a distorted octahedral coordination geometry, chelated by two N atoms from the 1,10'-phenanthroline ligand and four O atoms from two 2-methylbenzoate anions. A significant Jahn-Teller distortion is observed with two axial Cu-O distances significantly longer than those in the equatorial CuO2N2 plane. In the crystal, [pi]-[pi] stacking interactions, with centroid-centroid distances of 3.547 (3) or 3.728 (3) Å between the phenanthroline rings, form layers parallel to (011).

Comment top

The Jahn-Teller distortion of copper(II) complexes is well known. Most copper(II) complexes display an elongated distortion, and the coordinate bonds in the axial direction are usually longer than those in the equatorial coordination plane by 0.2–0.6 Å (Yang & Vittal, 2003; Su et al., 2005; Liu et al., 2010). Metal-phenanthroline complexes and their derivatives have also attracted much attention (Wang et al., 1996; Wall et al., 1999; Naing et al., 1995). In the title copper(II) phenanthroline complex, (I), a pair of long Cu-O bonds is observed.

The molecular structure of the title complex is shown in Fig. 1. The CuII ion binds to a phenanthroline molecule and two 2-methylbenzoate anions in a distorted octahedral geometry. Two N atoms from phen and two O atoms from carboxyl groups form a tetrahedrally distorted equatorial coordination plane, with a dihedral angle of 7.3 (2) ° between the Cu/O1/O3 and Cu/N1/N2 planes. The bond lengths in the equatorial plane are normal (Table 1). In the axial direction, the Cu-O distances (Cu-O2 2.609 (4) Å, Cu-O4 2.666 (4) Å) are longer than the Cu-O distances(Cu-O1 1.927 (4) Å, Cu-O3 1.919 (4) Å) equatorial plane.

The Cu-O-C angles of (Cu-O1-C13 105.9 (3) °, Cu-O3-C21 108.2 (3) °) are similar to values found in copper(II) complexes with a chelating benzoate ligand, for example, 106.1 (4) ° (Cano et al., 1997) and 104.5 (1) ° (Xu & Xu, 2004), but are much smaller than those in copper(II) complexes with a monodentate benzoate ligand, for example, 131.8 (1) ° (Rodrigues et al., 1999). This suggests the existence of a bonding interaction between atoms Cu and O2, Cu and O4. Besides the elongated Jahn-Teller distortion, the smaller O2-Cu-O4 angle of 132.1 (1) Å is also a possible reason for the larger differences within the same carboxylate group.

In the crystal structure two-dimensional layers form parallel to (011) through π–π packing interactions with centroid to centroid distances 3.547 (3) Å and 3.728 (3) Å between the phenanthroline rings, as shown in Fig. 2.

Related literature top

For Jahn–Teller distortions in copper complexes, see: Yang & Vittal (2003); Su et al. (2005); Liu et al. (2010). For phenanthroline complexes, see: Wang et al. (1996); Wall et al. (1999); Naing et al. (1995). For related structures, see: Cano et al. (1997); Rodrigues et al. (1999) Xu & Xu (2004).

Experimental top

Freshly prepared CuCO3 was essential for an optimal synthesis. 1.0 cm3 (1 M) aqueous Na2CO3 was added dropwise to a stirred aqueous solution of (0.2490 g, 1.0 mmol)CuSO4.5H2O in 4 cm3 of doubly distilled water. This produced a blue precipitate, of Cu(OH)2-2x(CO3)x.yH2O, which was centrifuged and washed with doubly distilled water until no SO4-2 anions were detected in the supernatant liquid. The fresh blue precipitate was subsequently added to a stirred solution of 2-methylbenzoic acid (0.2725 g, 2.0 mmol) and 1,10'-phenanthroline (0.1982 g, 1.0 mmol) in 20 cm3 C2H5OH-H2O (1:1, v/v). The mixture was stirred for 30 min and filtered. The insoluble solid was then filtered off, and the resulting blue filtrate (pH = 5.20) was allowed to stand at room temperature. Blue block-like crystals were grown by slow evaporation over a week. Yield: 45% based on the initial CuSO4.5 H2O.

Refinement top

All H-atoms bonded to C were positioned geometrically and refined using a riding model with d(C-H) = 0.093 Å, Uiso(H) = 1.2 Ueq(C) for aromatic, and 0.96 Å, Uiso(H) = 1.5 Ueq(C) for CH3 atoms. H atoms attached to O atoms were found in a difference Fourier synthesis and were refined using a riding model, with the O-H distances fixed as initially found and with Uiso(H) values set at 1.5 Ueq(O).

Computing details top

Data collection: RAPID-AUTO (Rigaku, 1998); cell refinement: RAPID-AUTO (Rigaku, 1998); data reduction: CrystalStructure (Rigaku/MSC, 2004); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. The structure of the title compound with dispalcement ellipsoids drawn at the 45% probability level.
[Figure 2] Fig. 2. Crystal packing showing the two-dimensional layer structure linked through π–π stacking interactions.
Bis(2-methylbenzoato-κ2O,O')(1,10'-phenanthroline- κ2N,N')copper(II) top
Crystal data top
[Cu(C8H7O2)2(C12H8N2)]F(000) = 1060
Mr = 514.02Dx = 1.495 Mg m−3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 25 reflections
a = 16.245 (3) Åθ = 3.0–25.0°
b = 10.136 (2) ŵ = 1.00 mm−1
c = 14.048 (3) ÅT = 293 K
β = 99.15 (3)°Plate, blue
V = 2283.7 (8) Å30.15 × 0.10 × 0.10 mm
Z = 4
Data collection top
Rigaku R-AXIS RAPID
diffractometer		4021 independent reflections
Radiation source: fine-focus sealed tube2509 reflections with I > 2σ(I)
graphiteRint = 0.063
ω scansθmax = 25.0°, θmin = 3.0°
Absorption correction: multi-scan
(ABSCOR; Higashi, 1995)		h = −19→19
Tmin = 0.866, Tmax = 0.900k = −12→12
17441 measured reflectionsl = −16→16
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)] = 0.045H-atom parameters constrained
wR(F2) = 0.150 w = 1/[σ2(Fo2) + (0.0447P)2 + 4.7675P]
where P = (Fo2 + 2Fc2)/3
S = 1.13(Δ/σ)max < 0.001
4021 reflectionsΔρmax = 0.74 e Å−3
319 parametersΔρmin = −1.04 e Å−3
0 restraintsExtinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.0013 (5)
Crystal data top
[Cu(C8H7O2)2(C12H8N2)]V = 2283.7 (8) Å3
Mr = 514.02Z = 4
Monoclinic, P21/cMo Kα radiation
a = 16.245 (3) ŵ = 1.00 mm−1
b = 10.136 (2) ÅT = 293 K
c = 14.048 (3) Å0.15 × 0.10 × 0.10 mm
β = 99.15 (3)°
Data collection top
Rigaku R-AXIS RAPID
diffractometer		4021 independent reflections
Absorption correction: multi-scan
(ABSCOR; Higashi, 1995)		2509 reflections with I > 2σ(I)
Tmin = 0.866, Tmax = 0.900Rint = 0.063
17441 measured reflectionsθmax = 25.0°
Refinement top
R[F2 > 2σ(F2)] = 0.045H-atom parameters constrained
wR(F2) = 0.150Δρmax = 0.74 e Å−3
S = 1.13Δρmin = −1.04 e Å−3
4021 reflectionsAbsolute structure: ?
319 parametersFlack parameter: ?
0 restraintsRogers parameter: ?
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
Cu−0.33221 (4)0.96309 (7)−0.17022 (4)0.0480 (2)
O1−0.2996 (2)1.1433 (4)−0.1871 (3)0.0703 (12)
O2−0.2404 (2)1.1033 (4)−0.0382 (3)0.0606 (10)
O3−0.2325 (2)0.8925 (4)−0.2077 (3)0.0635 (11)
O4−0.3140 (2)0.8977 (4)−0.3495 (3)0.0609 (10)
N1−0.3735 (2)0.7809 (4)−0.1419 (3)0.0450 (10)
N2−0.4462 (2)1.0137 (4)−0.1442 (3)0.0423 (9)
C1−0.3348 (4)0.6641 (6)−0.1404 (4)0.0584 (15)
H1−0.27940.6613−0.14960.070*
C2−0.3756 (5)0.5461 (6)−0.1255 (4)0.0698 (17)
H2−0.34710.4665−0.12510.084*
C3−0.4558 (4)0.5468 (6)−0.1115 (4)0.0607 (15)
H3−0.48250.4678−0.10240.073*
C4−0.4990 (3)0.6670 (5)−0.1108 (3)0.0478 (13)
C5−0.5834 (3)0.6805 (6)−0.0943 (4)0.0587 (15)
H5−0.61410.6053−0.08540.070*
C6−0.6191 (3)0.7998 (7)−0.0914 (4)0.0588 (15)
H6−0.67340.8055−0.07850.071*
C7−0.5753 (3)0.9185 (6)−0.1076 (3)0.0482 (13)
C8−0.6084 (4)1.0457 (6)−0.1077 (4)0.0606 (16)
H8−0.66271.0579−0.09620.073*
C9−0.5615 (4)1.1519 (6)−0.1244 (4)0.0623 (16)
H9−0.58331.2366−0.12350.075*
C10−0.4806 (4)1.1328 (5)−0.1431 (4)0.0565 (14)
H10−0.44941.2061−0.15520.068*
C11−0.4933 (3)0.9076 (5)−0.1268 (3)0.0395 (11)
C12−0.4540 (3)0.7812 (5)−0.1262 (3)0.0406 (11)
C13−0.2490 (3)1.1732 (5)−0.1108 (4)0.0476 (12)
C14−0.2009 (3)1.3008 (5)−0.1152 (3)0.0416 (11)
C15−0.2043 (3)1.3578 (5)−0.2067 (4)0.0509 (13)
H15−0.23481.3161−0.25990.061*
C16−0.1637 (3)1.4737 (6)−0.2196 (4)0.0619 (15)
H16−0.16601.5092−0.28110.074*
C17−0.1197 (4)1.5370 (6)−0.1411 (5)0.0667 (16)
H17−0.09281.6163−0.14900.080*
C18−0.1157 (3)1.4830 (6)−0.0517 (5)0.0604 (15)
H18−0.08591.52720.00080.072*
C19−0.1545 (3)1.3636 (5)−0.0356 (4)0.0496 (13)
C20−0.1458 (4)1.3130 (7)0.0666 (4)0.080 (2)
H20A−0.13271.22060.06760.120*
H20B−0.19731.32620.09070.120*
H20C−0.10191.36000.10630.120*
C21−0.2458 (3)0.8741 (5)−0.2988 (4)0.0494 (13)
C22−0.1747 (3)0.8162 (5)−0.3429 (3)0.0425 (11)
C23−0.1959 (3)0.7396 (5)−0.4251 (3)0.0531 (14)
H23−0.25170.7325−0.45270.064*
C24−0.1363 (4)0.6736 (6)−0.4669 (4)0.0615 (15)
H24−0.15170.6217−0.52140.074*
C25−0.0538 (4)0.6861 (6)−0.4265 (4)0.0612 (15)
H25−0.01300.6410−0.45280.073*
C26−0.0319 (3)0.7651 (6)−0.3470 (4)0.0555 (14)
H260.02430.7750−0.32200.067*
C27−0.0903 (3)0.8306 (5)−0.3028 (3)0.0430 (12)
C28−0.0598 (3)0.9171 (6)−0.2164 (4)0.0629 (16)
H18A−0.09090.9981−0.22150.094*
H28B−0.00170.9361−0.21440.094*
H28C−0.06760.8720−0.15840.094*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cu0.0409 (4)0.0540 (4)0.0480 (4)−0.0059 (3)0.0037 (3)0.0006 (3)
O10.067 (2)0.074 (3)0.063 (2)−0.024 (2)−0.011 (2)0.009 (2)
O20.075 (3)0.049 (2)0.057 (2)−0.006 (2)0.0108 (19)0.0059 (19)
O30.049 (2)0.094 (3)0.048 (2)−0.005 (2)0.0121 (17)0.000 (2)
O40.045 (2)0.060 (2)0.074 (3)−0.0035 (18)−0.0034 (18)0.005 (2)
N10.040 (2)0.053 (3)0.041 (2)0.010 (2)0.0046 (17)−0.003 (2)
N20.051 (2)0.035 (2)0.039 (2)0.0028 (19)0.0003 (18)0.0003 (18)
C10.059 (3)0.059 (4)0.056 (3)0.022 (3)0.005 (3)−0.002 (3)
C20.105 (5)0.041 (3)0.065 (4)0.018 (4)0.019 (4)0.004 (3)
C30.091 (5)0.044 (3)0.050 (3)−0.007 (3)0.019 (3)−0.001 (3)
C40.056 (3)0.047 (3)0.039 (3)−0.009 (3)0.001 (2)−0.003 (2)
C50.054 (3)0.075 (4)0.047 (3)−0.027 (3)0.005 (3)−0.001 (3)
C60.041 (3)0.084 (5)0.050 (3)−0.007 (3)0.004 (2)−0.007 (3)
C70.040 (3)0.062 (4)0.039 (3)0.006 (3)−0.002 (2)−0.005 (2)
C80.050 (3)0.078 (4)0.050 (3)0.025 (3)−0.002 (2)−0.009 (3)
C90.070 (4)0.059 (4)0.053 (3)0.031 (3)−0.004 (3)−0.009 (3)
C100.081 (4)0.040 (3)0.044 (3)0.006 (3)−0.004 (3)0.003 (2)
C110.039 (3)0.044 (3)0.033 (2)0.002 (2)−0.003 (2)−0.002 (2)
C120.041 (3)0.042 (3)0.035 (2)0.005 (2)−0.003 (2)−0.005 (2)
C130.041 (3)0.042 (3)0.061 (3)0.001 (2)0.013 (3)0.000 (3)
C140.036 (2)0.039 (3)0.050 (3)0.000 (2)0.007 (2)−0.001 (2)
C150.043 (3)0.054 (3)0.056 (3)−0.003 (2)0.006 (2)0.005 (3)
C160.057 (3)0.061 (4)0.071 (4)0.003 (3)0.021 (3)0.021 (3)
C170.060 (4)0.047 (3)0.096 (5)−0.006 (3)0.023 (3)0.000 (4)
C180.049 (3)0.053 (4)0.079 (4)−0.007 (3)0.008 (3)−0.018 (3)
C190.046 (3)0.053 (3)0.051 (3)−0.005 (3)0.011 (2)−0.006 (3)
C200.086 (5)0.098 (5)0.053 (4)−0.023 (4)0.002 (3)−0.003 (3)
C210.039 (3)0.053 (3)0.057 (3)−0.013 (2)0.007 (2)0.006 (3)
C220.044 (3)0.042 (3)0.043 (3)−0.005 (2)0.009 (2)0.007 (2)
C230.058 (3)0.056 (3)0.043 (3)−0.015 (3)0.002 (2)0.003 (3)
C240.088 (4)0.050 (3)0.049 (3)−0.014 (3)0.017 (3)−0.007 (3)
C250.070 (4)0.054 (4)0.063 (4)0.006 (3)0.022 (3)0.000 (3)
C260.051 (3)0.062 (4)0.053 (3)−0.001 (3)0.007 (3)0.002 (3)
C270.042 (3)0.041 (3)0.045 (3)−0.002 (2)0.007 (2)0.005 (2)
C280.048 (3)0.079 (4)0.061 (3)−0.014 (3)0.003 (3)−0.013 (3)
Geometric parameters (Å, °) top
Cu—O31.919 (4)C11—C121.431 (6)
Cu—O11.927 (4)C13—C141.518 (7)
Cu—N22.010 (4)C14—C191.399 (7)
Cu—N12.025 (4)C14—C151.402 (7)
O1—C131.279 (6)C15—C161.374 (7)
O2—C131.230 (6)C15—H150.9300
O3—C211.277 (6)C16—C171.374 (8)
O4—C211.240 (6)C16—H160.9300
N1—C11.339 (6)C17—C181.362 (8)
N1—C121.361 (6)C17—H170.9300
N2—C101.332 (6)C18—C191.399 (7)
N2—C111.364 (6)C18—H180.9300
C1—C21.399 (8)C19—C201.510 (7)
C1—H10.9300C20—H20A0.9600
C2—C31.348 (8)C20—H20B0.9600
C2—H20.9300C20—H20C0.9600
C3—C41.406 (7)C21—C221.515 (7)
C3—H30.9300C22—C231.388 (7)
C4—C121.404 (7)C22—C271.404 (6)
C4—C51.434 (7)C23—C241.382 (8)
C5—C61.345 (8)C23—H230.9300
C5—H50.9300C24—C251.375 (8)
C6—C71.435 (8)C24—H240.9300
C6—H60.9300C25—C261.374 (7)
C7—C81.398 (7)C25—H250.9300
C7—C111.404 (7)C26—C271.383 (7)
C8—C91.360 (8)C26—H260.9300
C8—H80.9300C27—C281.516 (7)
C9—C101.393 (8)C28—H18A0.9600
C9—H90.9300C28—H28B0.9600
C10—H100.9300C28—H28C0.9600
O3—Cu—O193.39 (18)O1—C13—C14115.7 (5)
O3—Cu—N2170.71 (16)C19—C14—C15118.9 (5)
O1—Cu—N293.45 (17)C19—C14—C13124.8 (4)
O3—Cu—N191.94 (17)C15—C14—C13116.3 (4)
O1—Cu—N1173.96 (17)C16—C15—C14121.6 (5)
N2—Cu—N181.58 (15)C16—C15—H15119.2
C13—O1—Cu105.9 (3)C14—C15—H15119.2
C21—O3—Cu108.2 (3)C15—C16—C17119.5 (5)
C1—N1—C12117.4 (5)C15—C16—H16120.3
C1—N1—Cu129.8 (4)C17—C16—H16120.3
C12—N1—Cu112.7 (3)C18—C17—C16119.7 (6)
C10—N2—C11117.7 (4)C18—C17—H17120.2
C10—N2—Cu129.3 (4)C16—C17—H17120.2
C11—N2—Cu113.0 (3)C17—C18—C19122.7 (5)
N1—C1—C2121.7 (5)C17—C18—H18118.7
N1—C1—H1119.1C19—C18—H18118.7
C2—C1—H1119.1C14—C19—C18117.6 (5)
C3—C2—C1120.6 (6)C14—C19—C20124.2 (5)
C3—C2—H2119.7C18—C19—C20118.1 (5)
C1—C2—H2119.7C19—C20—H20A109.5
C2—C3—C4120.0 (5)C19—C20—H20B109.5
C2—C3—H3120.0H20A—C20—H20B109.5
C4—C3—H3120.0C19—C20—H20C109.5
C12—C4—C3116.2 (5)H20A—C20—H20C109.5
C12—C4—C5118.7 (5)H20B—C20—H20C109.5
C3—C4—C5125.1 (5)O4—C21—O3122.7 (5)
C6—C5—C4121.3 (5)O4—C21—C22120.6 (5)
C6—C5—H5119.4O3—C21—C22116.6 (4)
C4—C5—H5119.4C23—C22—C27119.3 (5)
C5—C6—C7121.4 (5)C23—C22—C21116.9 (4)
C5—C6—H6119.3C27—C22—C21123.7 (4)
C7—C6—H6119.3C24—C23—C22121.7 (5)
C8—C7—C11116.7 (5)C24—C23—H23119.2
C8—C7—C6124.9 (5)C22—C23—H23119.2
C11—C7—C6118.4 (5)C25—C24—C23118.8 (5)
C9—C8—C7120.3 (5)C25—C24—H24120.6
C9—C8—H8119.9C23—C24—H24120.6
C7—C8—H8119.9C26—C25—C24119.9 (5)
C8—C9—C10119.6 (5)C26—C25—H25120.0
C8—C9—H9120.2C24—C25—H25120.0
C10—C9—H9120.2C25—C26—C27122.4 (5)
N2—C10—C9122.5 (5)C25—C26—H26118.8
N2—C10—H10118.7C27—C26—H26118.8
C9—C10—H10118.7C26—C27—C22117.7 (5)
N2—C11—C7123.2 (5)C26—C27—C28118.5 (4)
N2—C11—C12116.4 (4)C22—C27—C28123.7 (4)
C7—C11—C12120.3 (5)C27—C28—H18A109.5
N1—C12—C4124.1 (4)C27—C28—H28B109.5
N1—C12—C11116.1 (4)H18A—C28—H28B109.5
C4—C12—C11119.8 (4)C27—C28—H28C109.5
O2—C13—O1122.1 (5)H18A—C28—H28C109.5
O2—C13—C14122.2 (5)H28B—C28—H28C109.5
Table 1
Selected geometric parameters (Å) top
Cu—O31.919 (4)Cu—N22.010 (4)
Cu—O11.927 (4)Cu—N12.025 (4)
Acknowledgements top

This project was supported by the Foundation of the Education Department of Zhejiang Province (ZC200805662).

references
References top

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