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Acta Cryst. (2008). E64, m323    [ doi:10.1107/S1600536807068663 ]

Di-[mu]-bromido-bis({bis[2-(2-pyridyl)ethyl]amine}copper(II)) bis(perchlorate)

R. J. Butcher, Y. Gultneh, T. B. Yisgedu and Y. T. Tesema

Abstract top

Each Cu atom in the dinuclear centrosymmetric title complex, [Cu2Br2(C14H17N3)2](ClO4)2, is ligated in a distorted square-pyramidal geometry ([tau] = 0.31) by a tridentate bis[2-(2-pyridyl)ethyl]amine ligand, and by two bridging Br atoms. In addition, the dinuclear species is stabilized by two hydrogen-bonded perchlorate anions.

Comment top

Complex (I), Fig. 1, contains two Cu(II) atoms, each within a distorted square-pyramidal geometry (τ = 0.31, Addison et al., 1984) where one amine-N atom, two pyridine-N atoms and one Br atom constitute the basal plane with Cu—Npyridine = 2.012 (3) and 2.000 (3) Å, Cu—Namine = 2.044 (3) Å and Cu—Br = 2.4542 (7) Å. The axial position is occupied by the second Br atom with Cu—Br = 2.8908 (8) Å, the longer distance being consistent with a Jahn-Teller elongation. Pairs of these square-pyramidal Cu complexes form dimers about a center of inversion, being mutually bridged by the Br atoms. In addition, the dinuclear complex is stabilized by two N—H···O hydrogen bonded ClO4- anions (Table 1) and the crystal packing is consolidated by a variety of hydrogen bonding interactions (Fig. 2 and Table 1).

Related literature top

For related literature, see: Chakrabarty et al. (2004); Helis et al. (1977); Marsh et al. (1983); Udugala-Ganehenege, et al. (2001); Xu et al. (2000). For calculation of coordination geometry, see: Addison et al. (1984).

Experimental top

The title complex was synthesized by reacting Cu(ClO4)2.6H2O (0.37 g, 1 mmol), bis[2-(2-pyridyl)ethyl]amine (0.227 g, 1 mmol) and potassium bromide (0.0297 g, 0.25 mmol) in acetonitrile (15 ml) for 4 h at room temperature. X-ray quality crystals were grown by slow diffusion of diethyl ether into an acetonitrile solution of the complex.

Refinement top

The perchlorate anion is disordered over two conformations with occupancy factors, from refinement, of 0.543 (17) and 0.457 (17). It was constrained to adopt a tetrahedral geometry. The H atoms were idealized with N—H = 0.91 Å and C—H = 0.93 (aromatic C—H), 0.96 (CH3), and 0.97 (CH2) Å, and with Uiso(H) = 1.2Ueq(C) (1.5Ueq(C) for the CH3).

Computing details top

Data collection: XSCANS (Bruker, 1997); cell refinement: XSCANS (Bruker, 1997); data reduction: XSCANS (Bruker, 1997); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Bruker, 2000); software used to prepare material for publication: SHELXTL (Bruker, 2000).

Figures top
[Figure 1] Fig. 1. Complex (I) showing numbering scheme and displacement ellipsoids at the 20% probabilty level.
[Figure 2] Fig. 2. The packing arrangement viewed down the a axis showing the intramolecular N—H···O and intermolecular C—H···O interactions (dashed bonds).
Di-µ-bromido-bis({bis[2-(2-pyridyl)ethyl]amine}copper(II)) bis(perchlorate) top
Crystal data top
[Cu2Br2(C14H17N3)2](ClO4)2Z = 1
Mr = 940.41F000 = 470
Triclinic, P1Dx = 1.769 Mg m−3
Hall symbol: -P 1Mo Kα radiation
λ = 0.71073 Å
a = 6.8002 (13) ÅCell parameters from 49 reflections
b = 11.413 (2) Åθ = 2.1–12.5º
c = 12.668 (2) ŵ = 3.68 mm−1
α = 67.212 (8)ºT = 293 (2) K
β = 77.019 (13)ºThick needle, blue
γ = 87.033 (15)º0.42 × 0.21 × 0.18 mm
V = 882.6 (3) Å3
Data collection top
Bruker P4
diffractometer		Rint = 0.018
Radiation source: fine-focus sealed tubeθmax = 27.5º
Monochromator: graphiteθmin = 2.1º
T = 293(2) Kh = −8→0
ω scansk = −13→13
Absorption correction: ψ scan
(North et al., 1968)		l = −16→16
Tmin = 0.569, Tmax = 0.9483 standard reflections
3951 measured reflections every 97 reflections
3936 independent reflections intensity decay: <2%
2960 reflections with I > 2σ˘I)
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)] = 0.042H-atom parameters constrained
wR(F2) = 0.095  w = 1/[σ2(Fo2) + (0.0336P)2 + 0.6582P]
where P = (Fo2 + 2Fc2)/3
S = 1.04(Δ/σ)max < 0.001
3936 reflectionsΔρmax = 0.50 e Å−3
255 parametersΔρmin = −0.36 e Å−3
50 restraintsExtinction correction: none
Primary atom site location: structure-invariant direct methods
Crystal data top
[Cu2Br2(C14H17N3)2](ClO4)2γ = 87.033 (15)º
Mr = 940.41V = 882.6 (3) Å3
Triclinic, P1Z = 1
a = 6.8002 (13) ÅMo Kα
b = 11.413 (2) ŵ = 3.68 mm−1
c = 12.668 (2) ÅT = 293 (2) K
α = 67.212 (8)º0.42 × 0.21 × 0.18 mm
β = 77.019 (13)º
Data collection top
Bruker P4
diffractometer		2960 reflections with I > 2σ˘I)
Absorption correction: ψ scan
(North et al., 1968)		Rint = 0.018
Tmin = 0.569, Tmax = 0.9483 standard reflections
3951 measured reflections every 97 reflections
3936 independent reflections intensity decay: <2%
Refinement top
R[F2 > 2σ(F2)] = 0.04250 restraints
wR(F2) = 0.095H-atom parameters constrained
S = 1.04Δρmax = 0.50 e Å−3
3936 reflectionsΔρmin = −0.36 e Å−3
255 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*/UeqOcc. (<1)
Cu0.60810 (7)0.98360 (4)0.63720 (4)0.03731 (14)
Br0.76316 (6)0.97756 (4)0.44483 (3)0.03934 (12)
Cl0.19832 (18)1.27274 (11)0.86706 (12)0.0588 (3)
O11A0.062 (3)1.3663 (19)0.856 (2)0.149 (8)0.543 (17)
O12A0.117 (3)1.1516 (12)0.9388 (14)0.094 (5)0.543 (17)
O13A0.372 (2)1.2975 (11)0.8979 (15)0.110 (4)0.543 (17)
O14A0.2714 (18)1.2648 (13)0.7496 (8)0.101 (4)0.543 (17)
O11B0.010 (2)1.332 (2)0.8582 (19)0.100 (5)0.457 (17)
O12B0.346 (3)1.3175 (18)0.7719 (15)0.155 (7)0.457 (17)
O13B0.155 (3)1.1399 (11)0.9066 (16)0.072 (4)0.457 (17)
O14B0.256 (3)1.2875 (13)0.9664 (14)0.110 (5)0.457 (17)
N0.4740 (5)0.9948 (3)0.7943 (3)0.0424 (8)
H0A0.39201.06190.77550.051*
N1A0.6270 (5)0.7958 (3)0.7201 (3)0.0391 (7)
N1B0.6733 (5)1.1709 (3)0.5811 (3)0.0380 (7)
C1A0.8000 (7)0.7390 (4)0.6945 (4)0.0495 (10)
H1AA0.90930.78910.63980.059*
C2A0.8210 (9)0.6113 (5)0.7456 (5)0.0666 (14)
H2AA0.94330.57510.72790.080*
C3A0.6575 (9)0.5370 (5)0.8238 (5)0.0730 (16)
H3AA0.66620.44920.85720.088*
C4A0.4811 (8)0.5932 (4)0.8524 (4)0.0581 (12)
H4AA0.37020.54360.90580.070*
C5A0.4694 (6)0.7240 (4)0.8012 (3)0.0412 (9)
C6A0.2871 (6)0.7913 (4)0.8353 (4)0.0487 (10)
H6AA0.18590.72930.89420.058*
H6AB0.23040.83590.76720.058*
C7A0.3377 (8)0.8864 (4)0.8842 (4)0.0609 (13)
H7AA0.21340.91980.91440.073*
H7AB0.40220.84240.94920.073*
C1B0.6256 (7)1.2605 (4)0.4855 (4)0.0488 (10)
H1BA0.56191.23500.43970.059*
C2B0.6661 (8)1.3874 (4)0.4520 (5)0.0609 (13)
H2BA0.63391.44700.38420.073*
C3B0.7563 (8)1.4244 (5)0.5220 (6)0.0681 (15)
H3BA0.78191.51030.50310.082*
C4B0.8084 (7)1.3342 (5)0.6198 (5)0.0623 (14)
H4BA0.87251.35840.66620.075*
C5B0.7646 (6)1.2071 (4)0.6483 (4)0.0435 (10)
C6B0.8117 (7)1.1013 (5)0.7541 (4)0.0544 (12)
H6BB0.89241.13590.79020.065*
H6BC0.89171.04010.72900.065*
C7B0.6244 (7)1.0334 (5)0.8450 (4)0.0546 (12)
H7BB0.66420.95820.90430.065*
H7BC0.56131.08890.88350.065*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cu0.0479 (3)0.0350 (3)0.0253 (2)−0.0001 (2)−0.0020 (2)−0.01082 (19)
Br0.0328 (2)0.0541 (3)0.0300 (2)0.00276 (17)−0.00239 (15)−0.01773 (18)
Cl0.0517 (7)0.0459 (6)0.0707 (8)0.0054 (5)−0.0143 (6)−0.0138 (6)
O11A0.161 (13)0.099 (11)0.191 (11)0.081 (10)−0.070 (10)−0.051 (9)
O12A0.097 (8)0.071 (7)0.085 (8)−0.005 (6)0.011 (6)−0.013 (5)
O13A0.106 (8)0.093 (6)0.145 (10)−0.012 (6)−0.050 (7)−0.047 (7)
O14A0.080 (7)0.125 (9)0.080 (6)0.007 (6)0.004 (5)−0.035 (5)
O11B0.098 (8)0.102 (11)0.128 (9)0.067 (8)−0.054 (7)−0.065 (8)
O12B0.120 (10)0.146 (11)0.119 (10)−0.020 (8)0.044 (9)0.000 (9)
O13B0.066 (7)0.050 (5)0.109 (11)0.007 (5)−0.025 (7)−0.037 (6)
O14B0.146 (13)0.105 (8)0.104 (10)−0.010 (9)−0.058 (9)−0.048 (8)
N0.049 (2)0.0437 (19)0.0311 (17)0.0068 (16)−0.0029 (15)−0.0148 (15)
N1A0.047 (2)0.0372 (17)0.0296 (16)0.0006 (15)−0.0069 (14)−0.0102 (14)
N1B0.0389 (18)0.0410 (18)0.0323 (17)−0.0025 (14)−0.0032 (14)−0.0143 (14)
C1A0.049 (3)0.051 (3)0.044 (2)0.007 (2)−0.008 (2)−0.016 (2)
C2A0.074 (4)0.052 (3)0.062 (3)0.018 (3)−0.007 (3)−0.015 (3)
C3A0.097 (4)0.037 (3)0.069 (3)0.009 (3)−0.009 (3)−0.010 (2)
C4A0.071 (3)0.043 (3)0.045 (3)−0.006 (2)0.001 (2)−0.007 (2)
C5A0.050 (2)0.042 (2)0.0287 (19)−0.0002 (18)−0.0094 (17)−0.0101 (17)
C6A0.044 (2)0.046 (2)0.041 (2)−0.0035 (19)−0.0038 (19)−0.0031 (19)
C7A0.074 (3)0.052 (3)0.042 (2)0.002 (2)0.012 (2)−0.016 (2)
C1B0.055 (3)0.046 (2)0.045 (2)−0.002 (2)−0.012 (2)−0.016 (2)
C2B0.059 (3)0.044 (3)0.063 (3)−0.003 (2)−0.004 (2)−0.007 (2)
C3B0.058 (3)0.043 (3)0.097 (4)−0.011 (2)0.006 (3)−0.032 (3)
C4B0.049 (3)0.073 (3)0.079 (4)−0.015 (2)−0.004 (3)−0.047 (3)
C5B0.037 (2)0.057 (3)0.042 (2)−0.0043 (19)−0.0035 (18)−0.026 (2)
C6B0.045 (2)0.083 (3)0.045 (3)0.012 (2)−0.015 (2)−0.033 (2)
C7B0.060 (3)0.074 (3)0.032 (2)0.011 (2)−0.014 (2)−0.021 (2)
Geometric parameters (Å, °) top
Cu—N1A2.000 (3)C3A—C4A1.373 (7)
Cu—N1B2.012 (3)C3A—H3AA0.9300
Cu—N2.044 (3)C4A—C5A1.385 (6)
Cu—Br2.4542 (7)C4A—H4AA0.9300
Cu—Bri2.8908 (8)C5A—C6A1.494 (6)
Br—Cui2.8908 (8)C6A—C7A1.528 (7)
Cl—O12B1.326 (11)C6A—H6AA0.9700
Cl—O11A1.361 (11)C6A—H6AB0.9700
Cl—O12A1.388 (11)C7A—H7AA0.9700
Cl—O13A1.397 (9)C7A—H7AB0.9700
Cl—O13B1.424 (11)C1B—C2B1.366 (6)
Cl—O11B1.424 (11)C1B—H1BA0.9300
Cl—O14B1.469 (10)C2B—C3B1.379 (8)
Cl—O14A1.495 (9)C2B—H2BA0.9300
N—C7B1.488 (6)C3B—C4B1.375 (8)
N—C7A1.496 (5)C3B—H3BA0.9300
N—H0A0.9100C4B—C5B1.384 (6)
N1A—C5A1.349 (5)C4B—H4BA0.9300
N1A—C1A1.350 (5)C5B—C6B1.502 (6)
N1B—C1B1.342 (5)C6B—C7B1.517 (6)
N1B—C5B1.349 (5)C6B—H6BB0.9700
C1A—C2A1.361 (6)C6B—H6BC0.9700
C1A—H1AA0.9300C7B—H7BB0.9700
C2A—C3A1.374 (7)C7B—H7BC0.9700
C2A—H2AA0.9300
N1A—Cu—N1B159.15 (14)C5A—C4A—H4AA120.2
N1A—Cu—N89.40 (13)N1A—C5A—C4A120.4 (4)
N1B—Cu—N85.66 (13)N1A—C5A—C6A117.6 (4)
N1A—Cu—Br92.56 (9)C4A—C5A—C6A122.0 (4)
N1B—Cu—Br92.79 (9)C5A—C6A—C7A111.7 (4)
N—Cu—Br177.86 (10)C5A—C6A—H6AA109.3
N1A—Cu—Bri106.74 (10)C7A—C6A—H6AA109.3
N1B—Cu—Bri93.79 (10)C5A—C6A—H6AB109.3
N—Cu—Bri93.61 (10)C7A—C6A—H6AB109.3
Br—Cu—Bri85.00 (2)H6AA—C6A—H6AB107.9
Cu—Br—Cui95.00 (2)N—C7A—C6A112.9 (3)
O11A—Cl—O13A113.7 (9)N—C7A—H7AA109.0
O12A—Cl—O13A111.2 (9)C6A—C7A—H7AA109.0
O12B—Cl—O11B115.9 (11)N—C7A—H7AB109.0
O13B—Cl—O11B105.7 (9)C6A—C7A—H7AB109.0
O12B—Cl—O14B110.1 (9)H7AA—C7A—H7AB107.8
O13B—Cl—O14B104.4 (8)N1B—C1B—C2B123.3 (4)
O11B—Cl—O14B106.0 (9)N1B—C1B—H1BA118.4
O11A—Cl—O14A108.1 (10)C2B—C1B—H1BA118.4
O12A—Cl—O14A103.5 (7)C1B—C2B—C3B117.9 (5)
O13A—Cl—O14A105.2 (6)C1B—C2B—H2BA121.1
C7B—N—C7A112.0 (3)C3B—C2B—H2BA121.1
C7B—N—Cu110.9 (3)C4B—C3B—C2B119.9 (5)
C7A—N—Cu118.5 (3)C4B—C3B—H3BA120.0
C7B—N—H0A104.7C2B—C3B—H3BA120.0
C7A—N—H0A104.7C3B—C4B—C5B119.3 (5)
Cu—N—H0A104.7C3B—C4B—H4BA120.4
C5A—N1A—C1A119.0 (4)C5B—C4B—H4BA120.4
C5A—N1A—Cu121.3 (3)N1B—C5B—C4B120.9 (4)
C1A—N1A—Cu119.8 (3)N1B—C5B—C6B115.5 (4)
C1B—N1B—C5B118.7 (4)C4B—C5B—C6B123.6 (4)
C1B—N1B—Cu124.8 (3)C5B—C6B—C7B113.2 (4)
C5B—N1B—Cu116.4 (3)C5B—C6B—H6BB108.9
N1A—C1A—C2A122.7 (4)C7B—C6B—H6BB108.9
N1A—C1A—H1AA118.7C5B—C6B—H6BC108.9
C2A—C1A—H1AA118.7C7B—C6B—H6BC108.9
C1A—C2A—C3A118.5 (5)H6BB—C6B—H6BC107.8
C1A—C2A—H2AA120.7N—C7B—C6B113.2 (3)
C3A—C2A—H2AA120.7N—C7B—H7BB108.9
C4A—C3A—C2A119.7 (5)C6B—C7B—H7BB108.9
C4A—C3A—H3AA120.1N—C7B—H7BC108.9
C2A—C3A—H3AA120.1C6B—C7B—H7BC108.9
C3A—C4A—C5A119.6 (4)H7BB—C7B—H7BC107.7
C3A—C4A—H4AA120.2
N1A—Cu—Br—Cui106.59 (10)N1A—C1A—C2A—C3A1.8 (8)
N1B—Cu—Br—Cui−93.56 (10)C1A—C2A—C3A—C4A−2.8 (9)
N—Cu—Br—Cui−50 (3)C2A—C3A—C4A—C5A0.6 (8)
Bri—Cu—Br—Cui0.0C1A—N1A—C5A—C4A−3.7 (6)
N1A—Cu—N—C7B97.3 (3)Cu—N1A—C5A—C4A176.0 (3)
N1B—Cu—N—C7B−62.4 (3)C1A—N1A—C5A—C6A174.5 (4)
Br—Cu—N—C7B−106 (3)Cu—N1A—C5A—C6A−5.8 (5)
Bri—Cu—N—C7B−155.9 (3)C3A—C4A—C5A—N1A2.7 (7)
N1A—Cu—N—C7A−34.3 (3)C3A—C4A—C5A—C6A−175.4 (5)
N1B—Cu—N—C7A166.0 (3)N1A—C5A—C6A—C7A−58.6 (5)
Br—Cu—N—C7A122 (3)C4A—C5A—C6A—C7A119.6 (5)
Bri—Cu—N—C7A72.5 (3)C7B—N—C7A—C6A−142.0 (4)
N1B—Cu—N1A—C5A121.2 (4)Cu—N—C7A—C6A−10.9 (5)
N—Cu—N1A—C5A45.1 (3)C5A—C6A—C7A—N65.9 (5)
Br—Cu—N1A—C5A−134.1 (3)C5B—N1B—C1B—C2B0.4 (7)
Bri—Cu—N1A—C5A−48.5 (3)Cu—N1B—C1B—C2B177.7 (4)
N1B—Cu—N1A—C1A−59.1 (5)N1B—C1B—C2B—C3B−1.5 (7)
N—Cu—N1A—C1A−135.2 (3)C1B—C2B—C3B—C4B2.1 (8)
Br—Cu—N1A—C1A45.6 (3)C2B—C3B—C4B—C5B−1.7 (8)
Bri—Cu—N1A—C1A131.2 (3)C1B—N1B—C5B—C4B0.1 (6)
N1A—Cu—N1B—C1B157.2 (4)Cu—N1B—C5B—C4B−177.4 (3)
N—Cu—N1B—C1B−126.0 (3)C1B—N1B—C5B—C6B179.6 (4)
Br—Cu—N1B—C1B52.5 (3)Cu—N1B—C5B—C6B2.1 (4)
Bri—Cu—N1B—C1B−32.6 (3)C3B—C4B—C5B—N1B0.6 (7)
N1A—Cu—N1B—C5B−25.4 (5)C3B—C4B—C5B—C6B−178.9 (4)
N—Cu—N1B—C5B51.3 (3)N1B—C5B—C6B—C7B−66.2 (5)
Br—Cu—N1B—C5B−130.2 (3)C4B—C5B—C6B—C7B113.3 (5)
Bri—Cu—N1B—C5B144.7 (3)C7A—N—C7B—C6B156.6 (4)
C5A—N1A—C1A—C2A1.4 (7)Cu—N—C7B—C6B21.7 (5)
Cu—N1A—C1A—C2A−178.3 (4)C5B—C6B—C7B—N49.4 (5)
Symmetry codes: (i) −x+1, −y+2, −z+1.
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
N—H0A···O14A0.912.343.205 (12)159
N—H0A···O13B0.912.443.089 (18)129
C6A—H6AB···Bri0.972.703.588 (4)153
C6B—H6BC···Brii0.972.893.706 (4)142
C6B—H6BB···O13Biii0.972.573.487 (18)158
C2A—H2AA···O11Aiv0.932.523.162 (14)126
C7A—H7AA···O12Av0.972.513.322 (16)141
C7A—H7AA···O13B0.972.493.179 (15)128
C3A—H3AA···O13Avi0.932.543.142 (12)122
Symmetry codes: (i) −x+1, −y+2, −z+1; (ii) −x+2, −y+2, −z+1; (iii) x+1, y, z; (iv) x+1, y−1, z; (v) −x, −y+2, −z+2; (vi) x, y−1, z.
Table 1
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
N—H0A···O14A0.912.343.205 (12)159
N—H0A···O13B0.912.443.089 (18)129
C6A—H6AB···Bri0.972.703.588 (4)153
C6B—H6BC···Brii0.972.893.706 (4)142
C6B—H6BB···O13Biii0.972.573.487 (18)158
C2A—H2AA···O11Aiv0.932.523.162 (14)126
C7A—H7AA···O12Av0.972.513.322 (16)141
C7A—H7AA···O13B0.972.493.179 (15)128
C3A—H3AA···O13Avi0.932.543.142 (12)122
Symmetry codes: (i) −x+1, −y+2, −z+1; (ii) −x+2, −y+2, −z+1; (iii) x+1, y, z; (iv) x+1, y−1, z; (v) −x, −y+2, −z+2; (vi) x, y−1, z.
Acknowledgements top

RJB acknowledges the DoD for funds to uprade the diffractometer.

references
References top

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