Di-μ-bromido-bis­[bromido(di-2-pyridylmethane­diol-κ2N,N′)copper(II)] dihydrate

Westcott, B.L.; Kopp-Vaughn, K.M.; Daniels, L.M.; Zeller, M.

doi:10.1107/S1600536808024203

metal-organic compounds

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ISSN: 2056-9890

Volume 64| Part 9| September 2008| Pages m1122-m1123

doi:10.1107/S1600536808024203

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Di-μ-bromido-bis[bromido(di-2-pyridylmethanediol-κ²N,N′)copper(II)] dihydrate

Barry L. Westcott,^a ^* Kristin M. Kopp-Vaughn,^a Lee M. Daniels ^b and Matthias Zeller ^c

^aDepartment of Chemistry and Biochemistry, Central Connecticut State University, New Britain, CT 06050, USA, ^bRigaku Americas Corp., 9009 New Trails Dr., The Woodlands, TX 77381, USA, and ^cDepartment of Chemistry, Youngstown State University, Youngstown, OH 44555, USA
^*Correspondence e-mail: westcottb@ccsu.edu

(Received 20 June 2008; accepted 29 July 2008; online 6 August 2008)

The centrosymmetric title complex, [Cu₂Br₄(C₁₁H₁₀N₂O₂)₂]·2H₂O, was one of three complexes isolated by slow evaporation of an acetonitrile reaction mixture of CuBr₂ with di-2-pyridyl ketone (1:1 molar ratio). The title complex contains a 1:1 metal-to-ligand ratio of copper(II) with the hydrated form of the ligand di-2-pyridylmethanediol. The copper centers are bridged by bromide donors, leading to a Cu—Cu distance of 4.090 (6) Å. The crystals form as non-merohedral twins with two components related by a 180° rotation around the normal to [100]; the selected sample had a twin ratio of 0.63:0.37.

Related literature

Apart from the title complex, two others were isolated from the reaction mixture and structurally characterized. One complex was reported previously by Parker et al. (2000 ), the other is reported in the preceding paper by Zeller et al. (2008 ). For other related structures, see: Wang et al. (1986 ); Mariezcurrena et al. (1999 ).

Experimental

Crystal data

[Cu₂Br₄(C₁₁H₁₀N₂O₂)₂]·2H₂O
M_r = 887.18
Monoclinic, C 2/c
a = 21.2685 (7) Å
b = 9.1275 (3) Å
c = 14.4731 (4) Å
β = 100.749 (2)°
V = 2760.34 (15) Å³
Z = 4
Mo Kα radiation
μ = 7.38 mm⁻¹
T = 100 (2) K
0.34 × 0.25 × 0.13 mm

Data collection

Rigaku R-AXIS RAPID diffractometer
Absorption correction: multi-scan (TwinSolve; Rigaku/MSC, 2002 ) T_min = 0.08, T_max = 0.38
46376 measured reflections
7508 independent reflections
6192 reflections with I > 2σ(I)
R_int = 0.058

Refinement

R[F² > 2σ(F²)] = 0.065
wR(F²) = 0.198
S = 1.13
7508 reflections
185 parameters
2 restraints
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 1.54 e Å⁻³
Δρ_min = −1.58 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O3—H11⋯Br1ⁱ	0.85 (6)	2.53 (6)	3.361 (5)	166 (9)
O2—H9⋯O1ⁱⁱ	0.77 (6)	2.21 (7)	2.961 (7)	147 (9)
O2—H9⋯Br1ⁱⁱ	0.77 (6)	2.87 (9)	3.411 (5)	123 (8)
O3—H10⋯Br2	0.85 (6)	2.80 (8)	3.542 (6)	147 (9)
Symmetry codes: (i) $[x, -y+1, z-{\script{1\over 2}}]$ ; (ii) $[-x+{\script{1\over 2}}, -y+{\script{1\over 2}}, -z+1]$ .

Data collection: CrystalClear (Rigaku/MSC, 2004 ); cell refinement: TwinSolve (Rigaku/MSC, 2002); data reduction: TwinSolve; program(s) used to solve structure: SIR92 (Altomare et al., 1994 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ); molecular graphics: CrystalStructure (Rigaku, 2006 ); software used to prepare material for publication: publCIF (Westrip, 2008 ).

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536808024203/fj2132sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536808024203/fj2132Isup2.hkl

checkCIF report

Comment top

The title compound was one of three Cu–dpkoh complexes isolated from the 1:1 molar mixture of copper(II)bromide and di-2-pyridyl ketone, and was the third isolated from solution. The remaining two strutcures are described in Parker et al. (2000) and Zeller et al. (2008).

Related literature top

Apart from the title complex, two others were isolated from the reaction mixture and structurally characterized. One complex was reported previously by Parker et al. (2000), the other is reported by Zeller et al. (2008). For other related structures, see: Wang et al. (1986); Mariezcurrena et al. (1999).

Experimental top

Di-2-pyridyl ketone (dpk) was purchased from Aldrich and used as received. Copper(II) bromide hexahydrate was dried in an oven at 110°C for 48 h before use. DPK (1 mmol) and copper(II) bromide (1 mmol) were combined in 40 ml acetonitrile and stirred for 30 minutes. The resulting olive crystals were isolated after 5 days by slow evaporation of the solution. Prior to harvesting these crystals, crystals of two other distinct complexes were removed by gravity filtration.

Computing details top

Data collection: CrystalClear (Rigaku/MSC, 2004); cell refinement: TwinSolve (Rigaku/MSC, 2002); data reduction: TwinSolve (Rigaku/MSC, 2002); program(s) used to solve structure: SIR92 (Altomare et al., 1994); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: CrystalStructure (Rigaku, 2006); software used to prepare material for publication: publCIF (Westrip, 2008).

Figures top

	Fig. 1. ORTEP view of the unique part of the Cu complex, drawn with 60% probability displacement ellipsoids for the non-H atoms. The water molecule that loosely bridges Br atoms between adjacent complexes is not shown.
	Fig. 2. A view of the dimeric unit generated by the association of one of the Br ligands with the Cu atom of an adjacent molecule. The longer interactions of the Br and O atoms are shown as dashed lines. Non-H atoms are drawn with 60% probability ellipsoids.

Di-µ-bromido-bis[bromido(di-2-pyridylmethanediol-κ²N,N')copper(II)] dihydrate top

Crystal data top

[Cu₂Br₄(C₁₁H₁₀N₂O₂)₂]·2H₂O	F(000) = 1720
M_r = 887.18	D_x = 2.135 Mg m⁻³
Monoclinic, C2/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2yc	Cell parameters from 13358 reflections
a = 21.2685 (7) Å	θ = 2.7–29.8°
b = 9.1275 (3) Å	µ = 7.38 mm⁻¹
c = 14.4731 (4) Å	T = 100 K
β = 100.749 (2)°	Blocks, green
V = 2760.34 (15) Å³	0.34 × 0.25 × 0.13 mm
Z = 4

Data collection top

Rigaku R-AXIS RAPID diffractometer	7508 independent reflections
Radiation source: fine-focus sealed tube	6192 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.058
Detector resolution: 10 pixels mm^-1	θ_max = 30.1°, θ_min = 2.7°
ω scans	h = −29→29
Absorption correction: multi-scan (TwinSolve; Rigaku/MSC, 2002)	k = −12→12
T_min = 0.08, T_max = 0.38	l = −20→20
46376 measured reflections

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F² > 2σ(F²)] = 0.065	Hydrogen site location: difference Fourier map
wR(F²) = 0.198	H atoms treated by a mixture of independent and constrained refinement
S = 1.13	w = 1/[σ²(F_o²) + (0.0753P)² + 82.8356P] where P = (F_o² + 2F_c²)/3
7508 reflections	(Δ/σ)_max = 0.002
185 parameters	Δρ_max = 1.54 e Å⁻³
2 restraints	Δρ_min = −1.58 e Å⁻³

Crystal data top

[Cu₂Br₄(C₁₁H₁₀N₂O₂)₂]·2H₂O	V = 2760.34 (15) Å³
M_r = 887.18	Z = 4
Monoclinic, C2/c	Mo Kα radiation
a = 21.2685 (7) Å	µ = 7.38 mm⁻¹
b = 9.1275 (3) Å	T = 100 K
c = 14.4731 (4) Å	0.34 × 0.25 × 0.13 mm
β = 100.749 (2)°

Data collection top

Rigaku R-AXIS RAPID diffractometer	7508 independent reflections
Absorption correction: multi-scan (TwinSolve; Rigaku/MSC, 2002)	6192 reflections with I > 2σ(I)
T_min = 0.08, T_max = 0.38	R_int = 0.058
46376 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.065	2 restraints
wR(F²) = 0.198	H atoms treated by a mixture of independent and constrained refinement
S = 1.13	w = 1/[σ²(F_o²) + (0.0753P)² + 82.8356P] where P = (F_o² + 2F_c²)/3
7508 reflections	Δρ_max = 1.54 e Å⁻³
185 parameters	Δρ_min = −1.58 e Å⁻³

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

	x	y	z	U_iso*/U_eq
Br1	0.15441 (3)	0.62635 (7)	0.55691 (4)	0.01359 (14)
Br2	0.02135 (3)	0.54295 (7)	0.38142 (4)	0.01492 (15)
Cu1	0.08934 (3)	0.41245 (8)	0.50766 (5)	0.00990 (16)
O1	0.1794 (2)	0.2937 (5)	0.4473 (3)	0.0137 (8)
H12	0.165 (4)	0.306 (9)	0.394 (3)	0.014*
O2	0.2056 (2)	0.0447 (5)	0.4596 (4)	0.0163 (9)
H9	0.241 (2)	0.052 (10)	0.484 (6)	0.016*
O3	0.1174 (2)	0.3109 (6)	0.2691 (4)	0.0216 (10)
H10	0.091 (5)	0.391 (10)	0.270 (6)	0.022*
H11	0.126 (4)	0.334 (10)	0.215 (7)	0.022*
N1	0.1400 (2)	0.2914 (6)	0.6142 (4)	0.0121 (9)
N2	0.0544 (2)	0.2175 (6)	0.4509 (4)	0.0107 (9)
C1	0.1432 (3)	0.3159 (8)	0.7059 (5)	0.0199 (14)
H1	0.1210	0.3957	0.7238	0.024*
C2	0.1773 (3)	0.2300 (8)	0.7748 (5)	0.0208 (14)
H2	0.1792	0.2528	0.8379	0.025*
C3	0.2088 (3)	0.1091 (9)	0.7493 (5)	0.0231 (15)
H3	0.2320	0.0486	0.7951	0.028*
C4	0.2058 (3)	0.0783 (8)	0.6545 (5)	0.0168 (12)
H4	0.2256	−0.0045	0.6356	0.020*
C5	0.1724 (3)	0.1751 (7)	0.5888 (4)	0.0134 (11)
C6	0.1666 (3)	0.1538 (7)	0.4830 (4)	0.0103 (10)
C7	0.0974 (3)	0.1111 (6)	0.4443 (4)	0.0106 (10)
C8	0.0795 (3)	−0.0259 (7)	0.4077 (4)	0.0139 (11)
H5	0.1098	−0.0990	0.4065	0.017*
C9	0.0145 (3)	−0.0511 (7)	0.3725 (4)	0.0146 (11)
H6	0.0010	−0.1415	0.3465	0.017*
C10	−0.0295 (3)	0.0584 (7)	0.3766 (4)	0.0149 (12)
H7	−0.0727	0.0438	0.3522	0.018*
C11	−0.0078 (3)	0.1923 (7)	0.4184 (5)	0.0137 (11)
H8	−0.0374	0.2654	0.4237	0.016*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Br1	0.0089 (2)	0.0146 (3)	0.0168 (3)	0.0002 (2)	0.0011 (2)	−0.0018 (2)
Br2	0.0159 (3)	0.0139 (3)	0.0133 (3)	0.0015 (2)	−0.0015 (2)	0.0027 (2)
Cu1	0.0087 (3)	0.0108 (3)	0.0095 (3)	0.0007 (2)	−0.0003 (2)	−0.0002 (3)
O1	0.012 (2)	0.020 (2)	0.0103 (19)	−0.0023 (17)	0.0046 (16)	0.0041 (17)
O2	0.0081 (19)	0.018 (2)	0.023 (2)	0.0049 (17)	0.0022 (17)	−0.0022 (18)
O3	0.019 (2)	0.033 (3)	0.013 (2)	−0.002 (2)	0.0031 (18)	0.008 (2)
N1	0.007 (2)	0.017 (2)	0.011 (2)	−0.0003 (18)	−0.0015 (17)	0.0040 (19)
N2	0.010 (2)	0.011 (2)	0.011 (2)	0.0045 (18)	0.0031 (17)	0.0051 (18)
C1	0.020 (3)	0.028 (4)	0.013 (3)	−0.007 (3)	0.007 (2)	−0.009 (3)
C2	0.020 (3)	0.032 (4)	0.010 (3)	−0.009 (3)	0.001 (2)	0.001 (3)
C3	0.012 (3)	0.039 (4)	0.018 (3)	0.003 (3)	0.001 (2)	0.018 (3)
C4	0.007 (2)	0.024 (3)	0.019 (3)	0.001 (2)	0.001 (2)	0.009 (3)
C5	0.009 (2)	0.018 (3)	0.012 (3)	−0.001 (2)	0.001 (2)	0.000 (2)
C6	0.003 (2)	0.013 (3)	0.014 (3)	0.0023 (19)	0.0003 (19)	0.001 (2)
C7	0.012 (3)	0.010 (3)	0.010 (2)	0.003 (2)	0.004 (2)	0.003 (2)
C8	0.014 (3)	0.013 (3)	0.016 (3)	0.004 (2)	0.006 (2)	0.002 (2)
C9	0.014 (3)	0.015 (3)	0.014 (3)	−0.001 (2)	0.000 (2)	0.000 (2)
C10	0.010 (3)	0.019 (3)	0.015 (3)	−0.005 (2)	0.000 (2)	0.004 (2)
C11	0.011 (3)	0.012 (3)	0.017 (3)	0.003 (2)	0.000 (2)	0.005 (2)

Geometric parameters (Å, º) top

Br1—Cu1	2.4222 (10)	C2—C3	1.377 (11)
Br2—Cu1	2.4212 (9)	C2—H2	0.9300
Cu1—N1	2.034 (5)	C3—C4	1.390 (10)
Cu1—N2	2.041 (5)	C3—H3	0.9300
Cu1—Br2ⁱ	3.1138 (10)	C4—C5	1.392 (9)
O1—C6	1.423 (7)	C4—H4	0.9300
O1—H12	0.78 (4)	C5—C6	1.527 (8)
O2—C6	1.378 (7)	C6—C7	1.525 (8)
O2—H9	0.77 (4)	C7—C8	1.382 (9)
O3—H10	0.92 (10)	C8—C9	1.402 (9)
O3—H11	0.86 (10)	C8—H5	0.9300
N1—C1	1.335 (8)	C9—C10	1.377 (9)
N1—C5	1.353 (8)	C9—H6	0.9300
N2—C11	1.339 (8)	C10—C11	1.403 (9)
N2—C7	1.349 (7)	C10—H7	0.9300
C1—C2	1.367 (10)	C11—H8	0.9300
C1—H1	0.9300

N1—Cu1—N2	86.2 (2)	C3—C4—C5	118.0 (7)
N1—Cu1—Br2	175.12 (15)	C3—C4—H4	121.0
N2—Cu1—Br2	90.21 (14)	C5—C4—H4	121.0
N1—Cu1—Br1	91.25 (15)	N1—C5—C4	122.3 (6)
N2—Cu1—Br1	165.08 (15)	N1—C5—C6	115.0 (5)
Br2—Cu1—Br1	93.07 (3)	C4—C5—C6	122.7 (6)
N1—Cu1—Br2ⁱ	91.44 (15)	O2—C6—O1	113.3 (5)
N2—Cu1—Br2ⁱ	93.91 (15)	O2—C6—C7	108.0 (5)
Br2—Cu1—Br2ⁱ	85.54 (3)	O1—C6—C7	109.5 (4)
Br1—Cu1—Br2ⁱ	100.85 (3)	O2—C6—C5	113.5 (5)
C6—O1—H12	114 (6)	O1—C6—C5	105.3 (5)
C6—O2—H9	114 (7)	C7—C6—C5	107.1 (5)
H10—O3—H11	93 (8)	N2—C7—C8	122.5 (6)
C1—N1—C5	117.9 (6)	N2—C7—C6	114.2 (5)
C1—N1—Cu1	125.7 (5)	C8—C7—C6	123.3 (5)
C5—N1—Cu1	116.5 (4)	C7—C8—C9	118.0 (6)
C11—N2—C7	119.3 (5)	C7—C8—H5	121.0
C11—N2—Cu1	123.6 (4)	C9—C8—H5	121.0
C7—N2—Cu1	117.1 (4)	C10—C9—C8	119.9 (6)
N1—C1—C2	123.4 (7)	C10—C9—H6	120.1
N1—C1—H1	118.3	C8—C9—H6	120.1
C2—C1—H1	118.3	C9—C10—C11	118.6 (6)
C1—C2—C3	119.0 (6)	C9—C10—H7	120.7
C1—C2—H2	120.5	C11—C10—H7	120.7
C3—C2—H2	120.5	N2—C11—C10	121.7 (6)
C2—C3—C4	119.4 (6)	N2—C11—H8	119.2
C2—C3—H3	120.3	C10—C11—H8	119.2
C4—C3—H3	120.3

N2—Cu1—N1—C1	−131.0 (6)	C4—C5—C6—O2	−10.3 (9)
Br1—Cu1—N1—C1	63.9 (5)	N1—C5—C6—O1	49.0 (7)
N2—Cu1—N1—C5	47.9 (5)	C4—C5—C6—O1	−134.4 (6)
Br1—Cu1—N1—C5	−117.3 (4)	N1—C5—C6—C7	−67.6 (7)
N1—Cu1—N2—C11	131.8 (6)	C4—C5—C6—C7	109.0 (7)
Br1—Cu1—N2—C11	−147.0 (5)	C11—N2—C7—C8	−1.5 (9)
Br2—Cu1—N2—C11	−44.9 (5)	Cu1—N2—C7—C8	179.3 (5)
N1—Cu1—N2—C7	−49.1 (5)	C11—N2—C7—C6	179.7 (6)
Br2—Cu1—N2—C7	134.2 (4)	Cu1—N2—C7—C6	0.6 (7)
C5—N1—C1—C2	0.3 (10)	O2—C6—C7—N2	−171.3 (5)
Cu1—N1—C1—C2	179.1 (5)	O1—C6—C7—N2	−47.5 (7)
N1—C1—C2—C3	−2.1 (11)	C5—C6—C7—N2	66.6 (7)
C1—C2—C3—C4	0.8 (11)	O2—C6—C7—C8	10.0 (8)
C2—C3—C4—C5	2.2 (10)	O1—C6—C7—C8	133.8 (6)
C1—N1—C5—C4	2.9 (9)	C5—C6—C7—C8	−112.1 (7)
Cu1—N1—C5—C4	−176.0 (5)	N2—C7—C8—C9	3.0 (9)
C1—N1—C5—C6	179.6 (6)	C6—C7—C8—C9	−178.4 (6)
Cu1—N1—C5—C6	0.6 (7)	C7—C8—C9—C10	−2.0 (10)
C3—C4—C5—N1	−4.2 (10)	C7—N2—C11—C10	−1.0 (10)
C3—C4—C5—C6	179.4 (6)	C9—C10—C11—N2	1.9 (10)
N1—C5—C6—O2	173.1 (5)

Symmetry code: (i) −x, −y+1, −z+1.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O3—H11···Br1ⁱⁱ	0.85 (6)	2.53 (6)	3.361 (5)	166 (9)
O2—H9···O1ⁱⁱⁱ	0.77 (6)	2.21 (7)	2.961 (7)	147 (9)
O2—H9···Br1ⁱⁱⁱ	0.77 (6)	2.87 (9)	3.411 (5)	123 (8)
O3—H10···Br2	0.85 (6)	2.80 (8)	3.542 (6)	147 (9)

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

Experimental details

Crystal data
Chemical formula	[Cu₂Br₄(C₁₁H₁₀N₂O₂)₂]·2H₂O
M_r	887.18
Crystal system, space group	Monoclinic, C2/c
Temperature (K)	100
a, b, c (Å)	21.2685 (7), 9.1275 (3), 14.4731 (4)
β (°)	100.749 (2)
V (Å³)	2760.34 (15)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	7.38
Crystal size (mm)	0.34 × 0.25 × 0.13

Data collection
Diffractometer	Rigaku R-AXIS RAPID diffractometer
Absorption correction	Multi-scan (TwinSolve; Rigaku/MSC, 2002)
T_min, T_max	0.08, 0.38
No. of measured, independent and observed [I > 2σ(I)] reflections	46376, 7508, 6192
R_int	0.058
(sin θ/λ)_max (Å⁻¹)	0.705

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.065, 0.198, 1.13
No. of reflections	7508
No. of parameters	185
No. of restraints	2
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
	w = 1/[σ²(F_o²) + (0.0753P)² + 82.8356P] where P = (F_o² + 2F_c²)/3
Δρ_max, Δρ_min (e Å⁻³)	1.54, −1.58

Computer programs: CrystalClear (Rigaku/MSC, 2004), TwinSolve (Rigaku/MSC, 2002), SIR92 (Altomare et al., 1994), SHELXL97 (Sheldrick, 2008), CrystalStructure (Rigaku, 2006), publCIF (Westrip, 2008).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O3—H11···Br1ⁱ	0.85 (6)	2.53 (6)	3.361 (5)	166 (9)
O2—H9···O1ⁱⁱ	0.77 (6)	2.21 (7)	2.961 (7)	147 (9)
O2—H9···Br1ⁱⁱ	0.77 (6)	2.87 (9)	3.411 (5)	123 (8)
O3—H10···Br2	0.85 (6)	2.80 (8)	3.542 (6)	147 (9)

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

Acknowledgements

The authors thank Dr Guy Crundwell (CCSU) for helpful discussions. BLW acknowledges funding from the National Science Foundation (NSF #0420322). MZ acknowledge funding from the National Science Foundation (NSF #0087210) and the Ohio Board of Regents (CAP-491).

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