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Tetra-μ-acetato-κ8O:O′-bis­­{[2-(m-tolyl­amino)pyridine-κN]copper(II)}

aDepartment of Chemistry, University of Malaya, 50603 Kuala Lumpur, Malaysia
*Correspondence e-mail: seikweng@um.edu.my

(Received 20 November 2009; accepted 20 November 2009; online 28 November 2009)

In the crystal structure of the title compound, [Cu2(C2H3O2)4(C12H12N2)2], the binuclear mol­ecule lies about a center of inversion; the four acetate groups each bridge a pair of CuII atoms. The coordination of the metal atom is distorted square-pyramidal, with the bonding O atoms comprising a square basal plane and the coordinating N atom of the N-heterocycle occupying the apical position. The pyridine ring is twisted with respect to the benzene ring at a dihedral angle of 45.68 (16)°. Intra­molecular N—H⋯O hydrogen bonding is present between the imino and carb­oxy groups.

Related literature

There are many examples of tetra­kisacetatobis[(substituted pyridine)copper] complexes. For examples of 2-amino­pyridyl derivatives, see: Barquín et al. (2004[Barquín, M., González Garmendia, M. J., Pacheco, S., Pinilla, E., Quintela, S., Seco, J. M. & Torres, M. R. (2004). Inorg. Chim. Acta, 357, 3230-3236.]); Seco et al. (2004[Seco, J. M., González Garmendia, M. J., Pinilla, E. & Torres, M. R. (2004). Polyhedron, 21, 457-464.]); Sieroń (2004[Sieroń, L. (2004). Acta Cryst. E60, m577-m578.]).

[Scheme 1]

Experimental

Crystal data
  • [Cu2(C2H3O2)4(C12H12N2)2]

  • Mr = 731.73

  • Triclinic, [P \overline 1]

  • a = 7.7143 (2) Å

  • b = 10.5625 (3) Å

  • c = 11.2413 (3) Å

  • α = 66.531 (2)°

  • β = 85.740 (2)°

  • γ = 78.568 (2)°

  • V = 823.51 (4) Å3

  • Z = 1

  • Mo Kα radiation

  • μ = 1.35 mm−1

  • T = 293 K

  • 0.25 × 0.15 × 0.05 mm

Data collection
  • Bruker SMART APEX diffractometer

  • Absorption correction: multi-scan (SADABS; Sheldrick, 1996[Sheldrick, G. M. (1996). SADABS. University of Göttingen, Germany.]) Tmin = 0.730, Tmax = 0.936

  • 6451 measured reflections

  • 3678 independent reflections

  • 2915 reflections with I > 2σ(I)

  • Rint = 0.023

Refinement
  • R[F2 > 2σ(F2)] = 0.038

  • wR(F2) = 0.098

  • S = 1.07

  • 3678 reflections

  • 211 parameters

  • H-atom parameters constrained

  • Δρmax = 0.49 e Å−3

  • Δρmin = −0.59 e Å−3

Table 1
Selected bond lengths (Å)

Cu1—O1 1.9762 (19)
Cu1—O2i 1.9866 (19)
Cu1—O3 1.967 (2)
Cu1—O4i 1.966 (2)
Cu1—N1 2.197 (2)
Symmetry code: (i) -x+1, -y+1, -z+1.

Table 2
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N2—H2⋯O2i 0.86 2.17 2.913 (3) 145
Symmetry code: (i) -x+1, -y+1, -z+1.

Data collection: APEX2 (Bruker, 2008[Bruker (2008). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2008[Bruker (2008). APEX2 and SAINT. Bruker AXS 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: X-SEED (Barbour, 2001[Barbour, L. J. (2001). J. Supramol. Chem. 1, 189-191.]); software used to prepare material for publication: publCIF (Westrip, 2009[Westrip, S. P. (2009). publCIF. In preparation.]).

Supporting information


Related literature top

There are many examples of tetrakisacetatobis[(substituted pyridine)copper] complexes. For examples of 2-aminopyridyl derivatives, see: Barquín et al. (2004); Seco et al. (2004); Sieroń (2004).

Experimental top

Copper acetate (0.1 g, 0.5 mmol) was dissolved in acetonitrile (5 ml). The solution was mixed with a solution of 3-tolylamino-2-pyridine (0.2 g, 1.1 mmol) dissolved in acetonitrile (15 ml). The green precipitate that formed was recrystallized from acetonitrile.

Refinement top

Carbon-bound H-atoms were placed in calculated positions (C–H 0.93–0.96 Å) and were included in the refinement in the riding model approximation, with U(H) set to 1.2–1.5U(C). The amino H-atom was similarly treated.

Computing details top

Data collection: APEX2 (Bruker, 2008); cell refinement: SAINT (Bruker, 2008); data reduction: SAINT (Bruker, 2008); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: X-SEED (Barbour, 2001); software used to prepare material for publication: publCIF (Westrip, 2009).

Figures top
[Figure 1] Fig. 1. Thermal ellipsoid plot (Barbour, 2001) of Cu2(C2H3O2)4(C12H12N2)2 at the 50% probability level; hydrogen atoms are drawn as spheres of arbitrary radius. Dashed lines indicate the hydrogen bonding.
Tetra-µ-acetato-κ8O:O'-bis{[2-(m-tolylamino)pyridine- κN]copper(II)} top
Crystal data top
[Cu2(C2H3O2)4(C12H12N2)2]Z = 1
Mr = 731.73F(000) = 378
Triclinic, P1Dx = 1.475 Mg m3
Hall symbol: -P 1Mo Kα radiation, λ = 0.71073 Å
a = 7.7143 (2) ÅCell parameters from 2561 reflections
b = 10.5625 (3) Åθ = 2.3–27.6°
c = 11.2413 (3) ŵ = 1.35 mm1
α = 66.531 (2)°T = 293 K
β = 85.740 (2)°Prism, green
γ = 78.568 (2)°0.25 × 0.15 × 0.05 mm
V = 823.51 (4) Å3
Data collection top
Bruker SMART APEX
diffractometer
3678 independent reflections
Radiation source: fine-focus sealed tube2915 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.023
ω scansθmax = 27.5°, θmin = 2.0°
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
h = 109
Tmin = 0.730, Tmax = 0.936k = 1313
6451 measured reflectionsl = 1414
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)] = 0.038Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.098H-atom parameters constrained
S = 1.07 w = 1/[σ2(Fo2) + (0.0426P)2 + 0.4239P]
where P = (Fo2 + 2Fc2)/3
3678 reflections(Δ/σ)max = 0.001
211 parametersΔρmax = 0.49 e Å3
0 restraintsΔρmin = 0.59 e Å3
Crystal data top
[Cu2(C2H3O2)4(C12H12N2)2]γ = 78.568 (2)°
Mr = 731.73V = 823.51 (4) Å3
Triclinic, P1Z = 1
a = 7.7143 (2) ÅMo Kα radiation
b = 10.5625 (3) ŵ = 1.35 mm1
c = 11.2413 (3) ÅT = 293 K
α = 66.531 (2)°0.25 × 0.15 × 0.05 mm
β = 85.740 (2)°
Data collection top
Bruker SMART APEX
diffractometer
3678 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
2915 reflections with I > 2σ(I)
Tmin = 0.730, Tmax = 0.936Rint = 0.023
6451 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0380 restraints
wR(F2) = 0.098H-atom parameters constrained
S = 1.07Δρmax = 0.49 e Å3
3678 reflectionsΔρmin = 0.59 e Å3
211 parameters
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
Cu10.58894 (4)0.46743 (4)0.60797 (3)0.03044 (12)
O10.6955 (3)0.6324 (2)0.50147 (18)0.0439 (5)
O20.5505 (3)0.6857 (2)0.31997 (18)0.0419 (5)
O30.7582 (3)0.3494 (2)0.53769 (19)0.0460 (5)
O40.6100 (3)0.4052 (2)0.35536 (19)0.0436 (5)
N10.7506 (3)0.4120 (2)0.7806 (2)0.0304 (5)
N20.5409 (3)0.3175 (3)0.9254 (2)0.0446 (6)
H20.47710.34360.85730.053*
C10.6579 (4)0.7076 (3)0.3856 (3)0.0342 (6)
C20.7467 (5)0.8317 (4)0.3197 (3)0.0570 (9)
H2A0.84480.82370.37170.085*
H2B0.66370.91620.30910.085*
H2C0.78850.83460.23630.085*
C30.7354 (4)0.3375 (3)0.4329 (3)0.0378 (6)
C40.8709 (5)0.2335 (4)0.4000 (3)0.0578 (9)
H4A0.91750.15730.47840.087*
H4B0.96520.27870.35200.087*
H4C0.81690.19790.34850.087*
C50.9143 (4)0.4436 (3)0.7539 (3)0.0389 (7)
H50.94710.48350.66750.047*
C61.0348 (4)0.4198 (3)0.8479 (3)0.0438 (7)
H61.14540.44460.82590.053*
C70.9871 (4)0.3582 (3)0.9752 (3)0.0403 (7)
H71.06620.34001.04110.048*
C80.8228 (4)0.3236 (3)1.0051 (3)0.0395 (7)
H80.78960.28171.09120.047*
C90.7059 (3)0.3518 (3)0.9053 (2)0.0309 (6)
C100.4629 (4)0.2444 (3)1.0447 (2)0.0339 (6)
C110.3760 (4)0.1388 (3)1.0512 (3)0.0365 (6)
H110.37850.11490.97990.044*
C120.2858 (4)0.0682 (3)1.1613 (3)0.0417 (7)
C130.2886 (5)0.1024 (4)1.2678 (3)0.0513 (8)
H130.23270.05391.34400.062*
C140.3736 (5)0.2078 (4)1.2618 (3)0.0522 (8)
H140.37340.23021.33390.063*
C150.4592 (4)0.2808 (3)1.1506 (3)0.0420 (7)
H150.51370.35331.14680.050*
C160.1823 (5)0.0390 (4)1.1628 (4)0.0658 (10)
H16A0.22100.06851.09320.099*
H16B0.05870.00161.15220.099*
H16C0.20120.11871.24400.099*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cu10.02917 (19)0.0399 (2)0.02439 (17)0.01136 (14)0.00032 (12)0.01252 (14)
O10.0492 (13)0.0523 (13)0.0312 (10)0.0263 (10)0.0027 (9)0.0090 (9)
O20.0452 (12)0.0516 (13)0.0325 (10)0.0246 (10)0.0018 (9)0.0125 (9)
O30.0414 (12)0.0601 (14)0.0384 (11)0.0004 (10)0.0021 (9)0.0250 (10)
O40.0412 (12)0.0558 (13)0.0376 (11)0.0023 (10)0.0020 (9)0.0251 (10)
N10.0282 (12)0.0365 (13)0.0277 (11)0.0101 (10)0.0003 (9)0.0118 (10)
N20.0374 (14)0.0714 (18)0.0249 (11)0.0241 (13)0.0002 (10)0.0123 (12)
C10.0330 (15)0.0411 (16)0.0309 (14)0.0141 (12)0.0046 (11)0.0138 (12)
C20.065 (2)0.058 (2)0.0484 (19)0.0362 (19)0.0014 (16)0.0094 (16)
C30.0370 (16)0.0418 (17)0.0353 (15)0.0110 (13)0.0082 (12)0.0154 (13)
C40.058 (2)0.062 (2)0.051 (2)0.0063 (18)0.0032 (16)0.0289 (18)
C50.0349 (16)0.0487 (18)0.0323 (14)0.0123 (14)0.0022 (12)0.0133 (13)
C60.0298 (15)0.0532 (19)0.0489 (18)0.0094 (14)0.0038 (13)0.0191 (15)
C70.0344 (16)0.0476 (18)0.0387 (16)0.0007 (13)0.0117 (12)0.0179 (14)
C80.0398 (17)0.0489 (18)0.0277 (14)0.0074 (14)0.0039 (12)0.0125 (13)
C90.0293 (14)0.0353 (15)0.0289 (13)0.0068 (11)0.0014 (10)0.0129 (11)
C100.0299 (14)0.0421 (16)0.0272 (13)0.0056 (12)0.0013 (10)0.0117 (12)
C110.0327 (15)0.0406 (16)0.0362 (15)0.0027 (12)0.0003 (11)0.0171 (13)
C120.0366 (16)0.0317 (16)0.0494 (18)0.0040 (13)0.0041 (13)0.0100 (13)
C130.052 (2)0.055 (2)0.0358 (16)0.0099 (16)0.0131 (14)0.0090 (15)
C140.058 (2)0.068 (2)0.0357 (16)0.0142 (18)0.0102 (14)0.0261 (16)
C150.0450 (18)0.0476 (18)0.0385 (16)0.0129 (15)0.0054 (13)0.0210 (14)
C160.065 (3)0.047 (2)0.080 (3)0.0220 (19)0.006 (2)0.0163 (19)
Geometric parameters (Å, º) top
Cu1—O11.9762 (19)C4—H4C0.9600
Cu1—O2i1.9866 (19)C5—C61.372 (4)
Cu1—O31.967 (2)C5—H50.9300
Cu1—O4i1.966 (2)C6—C71.372 (4)
Cu1—N12.197 (2)C6—H60.9300
Cu1—Cu1i2.6532 (6)C7—C81.370 (4)
O1—C11.246 (3)C7—H70.9300
O2—C11.259 (3)C8—C91.393 (4)
O2—Cu1i1.9866 (19)C8—H80.9300
O3—C31.261 (3)C10—C111.387 (4)
O4—C31.250 (4)C10—C151.385 (4)
O4—Cu1i1.966 (2)C11—C121.384 (4)
N1—C91.339 (3)C11—H110.9300
N1—C51.352 (3)C12—C131.385 (4)
N2—C91.370 (3)C12—C161.503 (4)
N2—C101.413 (3)C13—C141.377 (5)
N2—H20.8600C13—H130.9300
C1—C21.498 (4)C14—C151.380 (4)
C2—H2A0.9600C14—H140.9300
C2—H2B0.9600C15—H150.9300
C2—H2C0.9600C16—H16A0.9600
C3—C41.500 (4)C16—H16B0.9600
C4—H4A0.9600C16—H16C0.9600
C4—H4B0.9600
O4i—Cu1—O3167.64 (8)H4A—C4—H4C109.5
O4i—Cu1—O188.77 (9)H4B—C4—H4C109.5
O3—Cu1—O190.33 (9)N1—C5—C6123.4 (3)
O4i—Cu1—O2i89.16 (9)N1—C5—H5118.3
O3—Cu1—O2i89.01 (9)C6—C5—H5118.3
O1—Cu1—O2i167.27 (8)C5—C6—C7118.1 (3)
O4i—Cu1—N198.40 (8)C5—C6—H6121.0
O3—Cu1—N193.96 (8)C7—C6—H6121.0
O1—Cu1—N194.60 (8)C8—C7—C6119.8 (3)
O2i—Cu1—N198.13 (8)C8—C7—H7120.1
O4i—Cu1—Cu1i84.47 (6)C6—C7—H7120.1
O3—Cu1—Cu1i83.19 (6)C7—C8—C9119.3 (3)
O1—Cu1—Cu1i83.69 (6)C7—C8—H8120.3
O2i—Cu1—Cu1i83.61 (6)C9—C8—H8120.3
N1—Cu1—Cu1i176.65 (6)N1—C9—N2115.0 (2)
C1—O1—Cu1124.57 (18)N1—C9—C8121.4 (2)
C1—O2—Cu1i123.80 (18)N2—C9—C8123.6 (2)
C3—O3—Cu1124.0 (2)C11—C10—C15119.4 (3)
C3—O4—Cu1i122.82 (18)C11—C10—N2117.7 (2)
C9—N1—C5118.0 (2)C15—C10—N2122.7 (3)
C9—N1—Cu1127.85 (17)C10—C11—C12121.6 (3)
C5—N1—Cu1114.18 (17)C10—C11—H11119.2
C9—N2—C10127.9 (2)C12—C11—H11119.2
C9—N2—H2116.1C13—C12—C11118.2 (3)
C10—N2—H2116.1C13—C12—C16121.2 (3)
O1—C1—O2124.3 (2)C11—C12—C16120.6 (3)
O1—C1—C2117.9 (2)C14—C13—C12120.5 (3)
O2—C1—C2117.8 (3)C14—C13—H13119.8
C1—C2—H2A109.5C12—C13—H13119.8
C1—C2—H2B109.5C13—C14—C15121.2 (3)
H2A—C2—H2B109.5C13—C14—H14119.4
C1—C2—H2C109.5C15—C14—H14119.4
H2A—C2—H2C109.5C14—C15—C10119.1 (3)
H2B—C2—H2C109.5C14—C15—H15120.5
O4—C3—O3125.3 (3)C10—C15—H15120.5
O4—C3—C4118.0 (3)C12—C16—H16A109.5
O3—C3—C4116.7 (3)C12—C16—H16B109.5
C3—C4—H4A109.5H16A—C16—H16B109.5
C3—C4—H4B109.5C12—C16—H16C109.5
H4A—C4—H4B109.5H16A—C16—H16C109.5
C3—C4—H4C109.5H16B—C16—H16C109.5
O4i—Cu1—O1—C184.3 (2)C9—N1—C5—C61.4 (4)
O3—Cu1—O1—C183.4 (2)Cu1—N1—C5—C6178.8 (2)
O2i—Cu1—O1—C13.6 (6)N1—C5—C6—C71.3 (5)
N1—Cu1—O1—C1177.4 (2)C5—C6—C7—C80.5 (5)
Cu1i—Cu1—O1—C10.3 (2)C6—C7—C8—C90.1 (5)
O4i—Cu1—O3—C30.2 (6)C5—N1—C9—N2177.5 (3)
O1—Cu1—O3—C385.6 (2)Cu1—N1—C9—N22.2 (4)
O2i—Cu1—O3—C381.7 (2)C5—N1—C9—C80.7 (4)
N1—Cu1—O3—C3179.8 (2)Cu1—N1—C9—C8179.6 (2)
Cu1i—Cu1—O3—C32.0 (2)C10—N2—C9—N1175.0 (3)
O4i—Cu1—N1—C958.8 (2)C10—N2—C9—C83.2 (5)
O3—Cu1—N1—C9121.1 (2)C7—C8—C9—N10.0 (4)
O1—Cu1—N1—C9148.2 (2)C7—C8—C9—N2178.1 (3)
O2i—Cu1—N1—C931.6 (2)C9—N2—C10—C11134.6 (3)
O4i—Cu1—N1—C5121.5 (2)C9—N2—C10—C1550.2 (5)
O3—Cu1—N1—C558.6 (2)C15—C10—C11—C120.2 (4)
O1—Cu1—N1—C532.0 (2)N2—C10—C11—C12175.6 (3)
O2i—Cu1—N1—C5148.2 (2)C10—C11—C12—C132.0 (4)
Cu1—O1—C1—O22.2 (4)C10—C11—C12—C16175.8 (3)
Cu1—O1—C1—C2178.1 (2)C11—C12—C13—C142.4 (5)
Cu1i—O2—C1—O13.4 (4)C16—C12—C13—C14175.4 (3)
Cu1i—O2—C1—C2176.9 (2)C12—C13—C14—C150.6 (5)
Cu1i—O4—C3—O35.7 (4)C13—C14—C15—C101.6 (5)
Cu1i—O4—C3—C4174.4 (2)C11—C10—C15—C142.0 (4)
Cu1—O3—C3—O45.2 (4)N2—C10—C15—C14177.2 (3)
Cu1—O3—C3—C4175.0 (2)
Symmetry code: (i) x+1, y+1, z+1.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N2—H2···O2i0.862.172.913 (3)145
Symmetry code: (i) x+1, y+1, z+1.

Experimental details

Crystal data
Chemical formula[Cu2(C2H3O2)4(C12H12N2)2]
Mr731.73
Crystal system, space groupTriclinic, P1
Temperature (K)293
a, b, c (Å)7.7143 (2), 10.5625 (3), 11.2413 (3)
α, β, γ (°)66.531 (2), 85.740 (2), 78.568 (2)
V3)823.51 (4)
Z1
Radiation typeMo Kα
µ (mm1)1.35
Crystal size (mm)0.25 × 0.15 × 0.05
Data collection
DiffractometerBruker SMART APEX
diffractometer
Absorption correctionMulti-scan
(SADABS; Sheldrick, 1996)
Tmin, Tmax0.730, 0.936
No. of measured, independent and
observed [I > 2σ(I)] reflections
6451, 3678, 2915
Rint0.023
(sin θ/λ)max1)0.649
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.038, 0.098, 1.07
No. of reflections3678
No. of parameters211
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.49, 0.59

Computer programs: APEX2 (Bruker, 2008), SAINT (Bruker, 2008), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), X-SEED (Barbour, 2001), publCIF (Westrip, 2009).

Selected bond lengths (Å) top
Cu1—O11.9762 (19)Cu1—O4i1.966 (2)
Cu1—O2i1.9866 (19)Cu1—N12.197 (2)
Cu1—O31.967 (2)
Symmetry code: (i) x+1, y+1, z+1.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N2—H2···O2i0.862.172.913 (3)145.0
Symmetry code: (i) x+1, y+1, z+1.
 

Acknowledgements

We thank the University of Malaya (grant No. RG027/09AFR, PS374/09 A) for supporting this study.

References

First citationBarbour, L. J. (2001). J. Supramol. Chem. 1, 189–191.  CrossRef CAS Google Scholar
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