metal-organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

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Bis{μ-4-chloro-2-[(2-pyridyleth­yl)imino­meth­yl]phenolato}bis­­[chloridocopper(II)]

aDepartment of Chemistry, Baoji University of Arts and Sciences, Baoji, Shaanxi 721007, People's Republic of China
*Correspondence e-mail: suojn@yahoo.com.cn

(Received 23 June 2008; accepted 15 July 2008; online 19 July 2008)

The title compound, [Cu2(C14H12ClN2O)2Cl2], is a copper(II) dimer where the metal centres are bridged by O atoms from a 5-chloro­salicylaldehyde group. The coordination geometry of each copper(II) centre is distorted square-pyramidal, with two N atoms from a 2-ethyl­amino­pyridine group and two O atoms from a 5-chloro­salicylaldehyde group occupying the basal positions, and with a Cl atom at the apical position. The dimer is centrosymmetric, with a crystallographic inversion centre midway between the two Cu atoms [Cu⋯Cu = 3.103 (9) Å].

Related literature

For related literature, see: Du et al. (2003[Du, M., Guo, Y.-M., Chen, S.-T., Bu, X.-H. & Ribas, J. (2003). Inorg. Chim. Acta, 346, 207-214.]); Rojas et al. (2004[Rojas, D., García, A. M., Vega, A., Moreno, Y., Venegas-Yazigi, D., Garland, M. T. & Manzur, J. (2004). Inorg. Chem. 43, 6324-6330.]); Yamada (1999[Yamada, S. (1999). Coord. Chem. Rev. 190-192, 537-555.]).

[Scheme 1]

Experimental

Crystal data
  • [Cu2(C14H12ClN2O)2Cl2]

  • Mr = 717.39

  • Monoclinic, P 21 /c

  • a = 9.9703 (10) Å

  • b = 9.0119 (11) Å

  • c = 16.5018 (16) Å

  • β = 96.0390 (10)°

  • V = 1474.5 (3) Å3

  • Z = 2

  • Mo Kα radiation

  • μ = 1.84 mm−1

  • T = 298 (2) K

  • 0.50 × 0.42 × 0.02 mm

Data collection
  • Bruker SMART CCD area-detector diffractometer

  • Absorption correction: multi-scan (SADABS; Sheldrick, 1996[Sheldrick, G. M. (1996). SADABS. University of Göttingen, Germany.]) Tmin = 0.460, Tmax = 0.957

  • 7139 measured reflections

  • 2587 independent reflections

  • 2101 reflections with I > 2σ(I)

  • Rint = 0.035

Refinement
  • R[F2 > 2σ(F2)] = 0.031

  • wR(F2) = 0.082

  • S = 1.05

  • 2587 reflections

  • 181 parameters

  • H-atom parameters constrained

  • Δρmax = 0.38 e Å−3

  • Δρmin = −0.32 e Å−3

Table 1
Selected bond lengths (Å)

Cu1—O1i 1.9547 (18)
Cu1—N2 1.958 (2)
Cu1—Cl2 2.3187 (9)
Symmetry code: (i) -x+1, -y+2, -z.

Data collection: SMART (Siemens, 1996[Siemens (1996). SMART and SAINT. Siemens Analytical X-ray Instruments Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Siemens, 1996[Siemens (1996). SMART and SAINT. Siemens Analytical X-ray Instruments Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); software used to prepare material for publication: SHELXTL.

Supporting information


Comment top

Transition metal complexes containing Schiff base ligands have been of great interest for many years (Yamada, 1999). These complexes play an important role in the coordination chemistry related to catalysis and enzymatic reactions, magnetism and molecular architectures. The complexes of salicylaldehyde with polyamines and bis(phenoxo) bridged dinuclear copper(II) complexes are rare. As an extension of the work on the structural characterization of Schiff base complexes, the crystal structure of a mononuclear copper(II) compound, (I), is reported here.

The molecular structure of complex (I) is defined by two [CuLCl] units [4-chloro-2-pyridylethylamine-phenolato], which are bridged by two atoms from 5-Chlorosalicylaldehyde, in such a way as to define a central N2CuO2CuN2 core. Additionally, there is an Cl atom from CuCl2.2H2O completing the pentacoordination of each Cu atom, thus defining a slightly distorted square-based pyramidal coordination for the metal centres. The basal square of the pyramid is defined by two N atoms (N1 and N2) from 2-ethylaminopyridine and two O atoms from 5-Chlorosalicylaldehyde [O1 and O1A; symmetry code: (A)-x + 1, y, -z].

The Cu—Cl2 distance is 2.3187 (9) Å,, which is a rather long value for the normal length of this kind of bond (2.0512 Å). A similar value has been reported for [Cu2(/m-oxalato) (dipyridylamino)2(CH3—CN)2](ClO4)2 (Du et al., 2003). The Cu—Cu distance of 3.103 (9) Å is close to this kind of complex (Rojas et al., 2004). Consistently, the O—Cu—O1A angle is 78.44 (8) °. The atom sequence Cu—O1—Cu1A—O1A is a rather parallelogram. The Cu—O1 and Cu—O1A distances are 1.9547 (18) Å and 2.0500 (19) °, respectively.

Related literature top

For related literature, see: Du et al. (2003); Rojas et al. (2004); Yamada (1999).

Experimental top

5-Chlorosalicylaldehyde (0.1 mmol, 15.7 mg), CuCl2.2H2O (0.1 mmol, 17.05 mg) and 2-ethylaminopyridine(0.1 mmol, 122.2 mg) were dissolved in methanol (10 ml). The mixture was stirred for 30 min at room temperature to give a clear brown solution. After allowing the resulting solution to stand in air for 11 d, brown block-shaped crystals of (I) were formed on slow evaporation of the solvent. The crystals were collected, washed with methanol and dried in a vacuum desiccator using anhydrous CaCl2 (yield 54%). Analysis found: C 46.84°, H 3.35° N 7.80°.calculated for Cu2(C14H12N2OCl2)2Cl2: C 46.86%, H 3.35%, N 7.81°.

Refinement top

All H atoms were placed in geometrically idealized positions and constrained to ride on their parent atoms with C—H distances in the range 0.93–0.97 Å and Uiso(H) = 1.2Ueq or 1.5Ueq(C/O)

Computing details top

Data collection: SMART (Siemens, 1996); cell refinement: SAINT (Siemens, 1996); data reduction: SAINT (Siemens, 1996); 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 in 30% probability ellipsoids. H atoms are omitted for clarity. [Symmetry code: (A)-x + 1, y, -z + 1]
[Figure 2] Fig. 2. The molecular packing of (I) viewed along the b axis.
Bis{µ-4-chloro-2-[(2-pyridylethyl)iminomethyl]phenolato}bis[chloridocopper(II)] top
Crystal data top
[Cu2(C14H12ClN2O)2Cl2]F(000) = 724
Mr = 717.39Dx = 1.616 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
a = 9.9703 (10) ÅCell parameters from 3383 reflections
b = 9.0119 (11) Åθ = 2.3–28.1°
c = 16.5018 (16) ŵ = 1.84 mm1
β = 96.039 (1)°T = 298 K
V = 1474.5 (3) Å3Block, brown
Z = 20.50 × 0.42 × 0.02 mm
Data collection top
Bruker SMART CCD area-detector
diffractometer
2587 independent reflections
Radiation source: fine-focus sealed tube2101 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.035
ϕ and ω scansθmax = 25.0°, θmin = 2.1°
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
h = 1111
Tmin = 0.460, Tmax = 0.957k = 1010
7139 measured reflectionsl = 1419
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)] = 0.031Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.082H-atom parameters constrained
S = 1.05 w = 1/[σ2(Fo2) + (0.0359P)2 + 0.6685P]
where P = (Fo2 + 2Fc2)/3
2587 reflections(Δ/σ)max = 0.001
181 parametersΔρmax = 0.38 e Å3
0 restraintsΔρmin = 0.32 e Å3
Crystal data top
[Cu2(C14H12ClN2O)2Cl2]V = 1474.5 (3) Å3
Mr = 717.39Z = 2
Monoclinic, P21/cMo Kα radiation
a = 9.9703 (10) ŵ = 1.84 mm1
b = 9.0119 (11) ÅT = 298 K
c = 16.5018 (16) Å0.50 × 0.42 × 0.02 mm
β = 96.039 (1)°
Data collection top
Bruker SMART CCD area-detector
diffractometer
2587 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
2101 reflections with I > 2σ(I)
Tmin = 0.460, Tmax = 0.957Rint = 0.035
7139 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0310 restraints
wR(F2) = 0.082H-atom parameters constrained
S = 1.05Δρmax = 0.38 e Å3
2587 reflectionsΔρmin = 0.32 e Å3
181 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
Cu10.40654 (3)0.92113 (4)0.05596 (2)0.03066 (13)
Cl11.06351 (9)0.91583 (13)0.29917 (6)0.0704 (3)
Cl20.29315 (9)1.11255 (9)0.11335 (5)0.0489 (2)
N10.3451 (2)0.7177 (2)0.01064 (14)0.0326 (5)
N20.4538 (2)0.8209 (2)0.16031 (13)0.0328 (5)
O10.60250 (18)0.9870 (2)0.05178 (11)0.0332 (5)
C10.3444 (3)0.7399 (4)0.19511 (18)0.0451 (8)
H1A0.31160.79900.23800.054*
H1B0.37960.64770.21910.054*
C20.2278 (3)0.7060 (3)0.13033 (19)0.0431 (8)
H2A0.16420.64150.15380.052*
H2B0.18140.79790.11470.052*
C30.2706 (3)0.6337 (3)0.05563 (18)0.0378 (7)
C40.2375 (4)0.4895 (4)0.0332 (2)0.0553 (9)
H40.18590.43160.06480.066*
C50.2823 (5)0.4327 (4)0.0368 (3)0.0684 (12)
H50.26130.33570.05260.082*
C60.3568 (4)0.5184 (4)0.0824 (2)0.0557 (10)
H60.38660.48120.13000.067*
C70.3882 (3)0.6617 (3)0.05733 (18)0.0423 (8)
H70.44010.72050.08820.051*
C80.5714 (3)0.8170 (3)0.19992 (16)0.0346 (7)
H80.57890.76240.24800.042*
C90.6936 (3)0.8864 (3)0.17933 (16)0.0304 (6)
C100.7074 (3)0.9662 (3)0.10664 (16)0.0304 (6)
C110.8341 (3)1.0216 (3)0.09434 (18)0.0392 (7)
H110.84531.07020.04580.047*
C120.9435 (3)1.0062 (4)0.15249 (19)0.0429 (8)
H121.02671.04630.14390.051*
C130.9277 (3)0.9303 (3)0.22358 (19)0.0418 (8)
C140.8076 (3)0.8687 (3)0.23679 (18)0.0387 (7)
H140.80050.81440.28410.046*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cu10.0349 (2)0.0311 (2)0.02574 (19)0.00498 (15)0.00216 (14)0.00274 (14)
Cl10.0410 (5)0.1083 (9)0.0574 (6)0.0051 (5)0.0164 (4)0.0100 (5)
Cl20.0554 (5)0.0391 (5)0.0541 (5)0.0034 (4)0.0150 (4)0.0099 (4)
N10.0365 (14)0.0285 (13)0.0315 (13)0.0010 (11)0.0028 (10)0.0010 (10)
N20.0392 (14)0.0313 (13)0.0285 (12)0.0062 (11)0.0061 (10)0.0022 (10)
O10.0299 (11)0.0400 (11)0.0286 (10)0.0046 (9)0.0018 (8)0.0094 (9)
C10.048 (2)0.053 (2)0.0358 (17)0.0115 (16)0.0077 (14)0.0078 (15)
C20.0405 (18)0.0408 (18)0.0485 (19)0.0105 (15)0.0071 (14)0.0110 (15)
C30.0378 (18)0.0288 (16)0.0441 (18)0.0024 (13)0.0078 (14)0.0052 (13)
C40.067 (2)0.0361 (19)0.059 (2)0.0146 (17)0.0094 (18)0.0057 (17)
C50.090 (3)0.032 (2)0.077 (3)0.001 (2)0.022 (2)0.0097 (19)
C60.073 (3)0.042 (2)0.050 (2)0.0119 (19)0.0068 (18)0.0130 (17)
C70.0445 (19)0.0434 (19)0.0376 (17)0.0064 (15)0.0026 (14)0.0032 (14)
C80.0470 (19)0.0328 (16)0.0236 (14)0.0004 (14)0.0017 (12)0.0027 (12)
C90.0344 (16)0.0293 (15)0.0270 (15)0.0006 (12)0.0009 (12)0.0026 (11)
C100.0345 (16)0.0268 (15)0.0293 (15)0.0010 (12)0.0006 (12)0.0015 (11)
C110.0358 (18)0.0423 (18)0.0393 (17)0.0025 (14)0.0028 (13)0.0081 (14)
C120.0275 (16)0.0469 (19)0.053 (2)0.0012 (14)0.0005 (14)0.0035 (16)
C130.0336 (18)0.0494 (19)0.0402 (18)0.0040 (15)0.0070 (13)0.0002 (15)
C140.0416 (19)0.0407 (17)0.0321 (16)0.0058 (14)0.0031 (13)0.0030 (13)
Geometric parameters (Å, º) top
Cu1—O1i1.9547 (18)C4—C51.381 (5)
Cu1—N21.958 (2)C4—H40.9300
Cu1—N12.049 (2)C5—C61.353 (6)
Cu1—O12.0500 (19)C5—H50.9300
Cu1—Cl22.3187 (9)C6—C71.382 (5)
Cl1—C131.747 (3)C6—H60.9300
N1—C31.339 (4)C7—H70.9300
N1—C71.341 (4)C8—C91.441 (4)
N2—C81.282 (4)C8—H80.9300
N2—C11.478 (4)C9—C141.411 (4)
O1—C101.323 (3)C9—C101.417 (4)
O1—Cu1i1.9547 (18)C10—C111.392 (4)
C1—C21.525 (4)C11—C121.382 (4)
C1—H1A0.9700C11—H110.9300
C1—H1B0.9700C12—C131.381 (4)
C2—C31.495 (4)C12—H120.9300
C2—H2A0.9700C13—C141.358 (4)
C2—H2B0.9700C14—H140.9300
C3—C41.382 (4)
O1i—Cu1—N2168.33 (9)C5—C4—C3118.9 (4)
O1i—Cu1—N193.65 (9)C5—C4—H4120.5
N2—Cu1—N186.74 (9)C3—C4—H4120.5
O1i—Cu1—O178.44 (8)C6—C5—C4119.9 (3)
N2—Cu1—O191.22 (8)C6—C5—H5120.0
N1—Cu1—O1119.75 (9)C4—C5—H5120.0
O1i—Cu1—Cl294.50 (6)C5—C6—C7119.1 (3)
N2—Cu1—Cl293.82 (7)C5—C6—H6120.4
N1—Cu1—Cl2132.43 (7)C7—C6—H6120.4
O1—Cu1—Cl2107.80 (6)N1—C7—C6121.3 (3)
C3—N1—C7119.7 (3)N1—C7—H7119.3
C3—N1—Cu1117.75 (19)C6—C7—H7119.3
C7—N1—Cu1122.2 (2)N2—C8—C9128.2 (3)
C8—N2—C1117.5 (2)N2—C8—H8115.9
C8—N2—Cu1125.7 (2)C9—C8—H8115.9
C1—N2—Cu1116.79 (18)C14—C9—C10118.9 (3)
C10—O1—Cu1i129.79 (18)C14—C9—C8115.7 (3)
C10—O1—Cu1128.60 (17)C10—C9—C8125.4 (2)
Cu1i—O1—Cu1101.56 (8)O1—C10—C11120.9 (3)
N2—C1—C2111.4 (2)O1—C10—C9120.7 (3)
N2—C1—H1A109.3C11—C10—C9118.4 (3)
C2—C1—H1A109.3C12—C11—C10121.6 (3)
N2—C1—H1B109.3C12—C11—H11119.2
C2—C1—H1B109.3C10—C11—H11119.2
H1A—C1—H1B108.0C13—C12—C11119.2 (3)
C3—C2—C1113.7 (3)C13—C12—H12120.4
C3—C2—H2A108.8C11—C12—H12120.4
C1—C2—H2A108.8C14—C13—C12121.3 (3)
C3—C2—H2B108.8C14—C13—Cl1119.0 (2)
C1—C2—H2B108.8C12—C13—Cl1119.6 (3)
H2A—C2—H2B107.7C13—C14—C9120.5 (3)
N1—C3—C4121.0 (3)C13—C14—H14119.7
N1—C3—C2115.7 (3)C9—C14—H14119.7
C4—C3—C2123.3 (3)
O1i—Cu1—N1—C3146.8 (2)C1—C2—C3—N166.8 (3)
N2—Cu1—N1—C344.9 (2)C1—C2—C3—C4112.9 (3)
O1—Cu1—N1—C3134.4 (2)N1—C3—C4—C50.2 (5)
Cl2—Cu1—N1—C347.3 (2)C2—C3—C4—C5179.8 (3)
O1i—Cu1—N1—C740.0 (2)C3—C4—C5—C60.3 (6)
N2—Cu1—N1—C7128.3 (2)C4—C5—C6—C70.7 (6)
O1—Cu1—N1—C738.7 (2)C3—N1—C7—C60.2 (4)
Cl2—Cu1—N1—C7139.5 (2)Cu1—N1—C7—C6173.2 (2)
O1i—Cu1—N2—C828.7 (6)C5—C6—C7—N10.7 (5)
N1—Cu1—N2—C8121.0 (2)C1—N2—C8—C9179.8 (3)
O1—Cu1—N2—C81.2 (2)Cu1—N2—C8—C91.8 (4)
Cl2—Cu1—N2—C8106.7 (2)N2—C8—C9—C14177.1 (3)
O1i—Cu1—N2—C1149.7 (4)N2—C8—C9—C104.4 (5)
N1—Cu1—N2—C157.5 (2)Cu1i—O1—C10—C114.6 (4)
O1—Cu1—N2—C1177.2 (2)Cu1—O1—C10—C11178.7 (2)
Cl2—Cu1—N2—C174.8 (2)Cu1i—O1—C10—C9175.26 (18)
O1i—Cu1—O1—C10177.4 (3)Cu1—O1—C10—C91.4 (4)
N2—Cu1—O1—C102.9 (2)C14—C9—C10—O1179.1 (3)
N1—Cu1—O1—C1089.8 (2)C8—C9—C10—O12.5 (4)
Cl2—Cu1—O1—C1091.5 (2)C14—C9—C10—C111.1 (4)
O1i—Cu1—O1—Cu1i0.0C8—C9—C10—C11177.4 (3)
N2—Cu1—O1—Cu1i174.53 (10)O1—C10—C11—C12177.3 (3)
N1—Cu1—O1—Cu1i87.59 (11)C9—C10—C11—C122.9 (4)
Cl2—Cu1—O1—Cu1i91.06 (8)C10—C11—C12—C131.8 (5)
C8—N2—C1—C2159.3 (3)C11—C12—C13—C141.1 (5)
Cu1—N2—C1—C219.3 (3)C11—C12—C13—Cl1177.7 (2)
N2—C1—C2—C350.8 (4)C12—C13—C14—C92.9 (5)
C7—N1—C3—C40.2 (4)Cl1—C13—C14—C9175.9 (2)
Cu1—N1—C3—C4173.1 (2)C10—C9—C14—C131.7 (4)
C7—N1—C3—C2179.8 (3)C8—C9—C14—C13179.7 (3)
Cu1—N1—C3—C26.5 (3)
Symmetry code: (i) x+1, y+2, z.

Experimental details

Crystal data
Chemical formula[Cu2(C14H12ClN2O)2Cl2]
Mr717.39
Crystal system, space groupMonoclinic, P21/c
Temperature (K)298
a, b, c (Å)9.9703 (10), 9.0119 (11), 16.5018 (16)
β (°) 96.039 (1)
V3)1474.5 (3)
Z2
Radiation typeMo Kα
µ (mm1)1.84
Crystal size (mm)0.50 × 0.42 × 0.02
Data collection
DiffractometerBruker SMART CCD area-detector
diffractometer
Absorption correctionMulti-scan
(SADABS; Sheldrick, 1996)
Tmin, Tmax0.460, 0.957
No. of measured, independent and
observed [I > 2σ(I)] reflections
7139, 2587, 2101
Rint0.035
(sin θ/λ)max1)0.595
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.031, 0.082, 1.05
No. of reflections2587
No. of parameters181
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.38, 0.32

Computer programs: SMART (Siemens, 1996), SAINT (Siemens, 1996), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Selected bond lengths (Å) top
Cu1—O1i1.9547 (18)Cu1—Cl22.3187 (9)
Cu1—N21.958 (2)
Symmetry code: (i) x+1, y+2, z.
 

Acknowledgements

The author thanks the Science and Educational Fund of Shaanxi Province for a research grant (No. 06k16-G16).

References

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