catena-Poly[[aqua­bromidocopper(II)]-μ₃-(picolinato N-oxide)]

Abstract

The title complex, [CuBr(C₆H₄NO₃)(H₂O)]_n, exhibits a layered structure which is stabilized by inter­molecular O—H⋯O and O—H⋯Br⁻ hydrogen bonds, van der Waals forces and π–π inter­actions [centroid–centroid distance = 3.747(4) Å] between the parallel pyridine rings from two neighboring layers.

Related literature

For the isotypic chlorido complex, see: Yang et al. (2004 ▶). For the synthesis, see: Wu et al. (2007 ▶).

Experimental

Crystal data

• [CuBr(C₆H₄NO₃)(H₂O)]

• M _r = 299.57

• Monoclinic,

• a = 9.7116 (3) Å

• b = 10.0302 (2) Å

• c = 9.4984 (3) Å

• β = 110.821 (2)°

• V = 864.81 (4) ų

• Z = 4

• Mo Kα radiation

• μ = 7.12 mm⁻¹

• T = 173 K

• 0.52 × 0.35 × 0.22 mm

Data collection

• Bruker SMART CCD area-detector diffractometer

• Absorption correction: multi-scan (SADABS; Sheldrick, 1996 ▶) T _min = 0.095, T _max = 0.241

• 2584 measured reflections

• 1515 independent reflections

• 1420 reflections with I > 2σ(I)

• R _int = 0.027

Refinement

• R[F ² > 2σ(F ²)] = 0.044

• wR(F ²) = 0.127

• S = 1.00

• 1515 reflections

• 118 parameters

• H-atom parameters constrained

• Δρ_max = 1.09 e Å⁻³

• Δρ_min = −0.93 e Å⁻³

Data collection: SMART (Bruker, 1999 ▶); cell refinement: SAINT (Bruker, 1999 ▶); data reduction: SAINT; 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.

Supplementary Material

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Table 1. Hydrogen-bond geometry (Å, °).

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O4—H4B2⋯O2i	0.85	1.97	2.738 (5)	149
O4—H4B2⋯Br1i	0.85	3.07	3.741 (4)	137
O4—H4B1⋯Br1ii	0.85	2.59	3.377 (4)	155

Symmetry codes: (i) ; (ii) .

supplementary crystallographic information

Comment

The title complex, [(C₆H₄NO₃)(H₂O)BrCu]_n, is isomorphous with the chloro complex (Yang et al., 2004). The atoms of C1,C2,C3,C4,C5,C6,N1 and O1 lie in a plane with r.m.s. of 0.0095Å (Figure 1). The Cu(II) ion is 6-coordinated by a bidentate picolinate N-oxide chelating ligand (O1 and O2), a N-oxide oxygen atom and a carboxylate oxygen atom from two other ligands, an aqua ligand and a bromine anion (Figure 2). The two axial Cu—O bond lengths Cu-O1 and Cu-O3 are 2.449 (4) and 2.499 (4)Å and are longer than those reported for the chloride complex (Yang et al., 2004), while the Cu—O4 bond length of 1.990 (4)Å is shorter. The distance of Cu—Br is 2.403 (8)Å.

The complex exhibits a layered crystal structure which is stabilized by intermolecular O—H···O and O—H···Br^- hydrogen bonds, van der Waals forces and π-π interactions between parallel pyridine rings from two neighboring layers (Figure 2). The distances between the layers are 3.318 (2) Å. The title complex forms Cu₂O₂ units interconnected via 2-carboxylic acid-pyridine-N-oxide ligands, and such unit formed a parallelogram (Figure 2).

Experimental

The title complex was synthesized according to the method of Wu et al., (2007). The CuBr₂ (0.1 g, 0.5 mmol) was dissolved in 20 ml methanol(20 ml), then 2-carboxylic acid-pyridine-N-oxide (0.07 g, 0.5 mmol) in THF (20 ml) was added slowly. The mixture was then stirred for a few hours. Brown crystals of the title complex were grown from the mother liquor by slow evapovation after three weeks.

Refinement

The position of the water H atoms were located in a difference Fourier map. However, during refinement, they were restrained to O—H=0.85 Å. The U_iso of each H atom = 1.5U_eq(O). The C-bound H atoms were included in the riding model approximation with C—H = 0.95 Å. The U_iso of each H atom = 1.2U_eq(C).

Figures

Fig. 1.

ORTEP drawing (at 30% probability) of the compound structure. [Symmetry code: (A) 1-x, 1-y, 1-z (B) x, 0.5-y, -0.5+z (C) 1-x, 0.5+y, 1.5-z].

Fig. 2.

Crystal Packing diagram of the title compound, showing the H-bonded interactions (dashed lines),π-π interactions diagram. [Symmetry code: (A) 1-x, -0.5+y, 0.5-z (B) x, 0.5-y, -0.5+z].

Fig. 3.

Packing diagram.

Fig. 4.

Packing diagram.

Crystal data

[CuBr(C6H4NO3)(H2O)]	F(000) = 580
Mr = 299.57	Dx = 2.301 Mg m−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 1539 reflections
a = 9.7116 (3) Å	θ = 2.2–25.1°
b = 10.0302 (2) Å	µ = 7.12 mm−1
c = 9.4984 (3) Å	T = 173 K
β = 110.821 (2)°	Prism, brown
V = 864.81 (4) Å3	0.52 × 0.35 × 0.22 mm
Z = 4

Data collection

Bruker SMART CCD area-detector diffractometer	1515 independent reflections
Radiation source: fine-focus sealed tube	1420 reflections with I > 2σ(I)
graphite	Rint = 0.027
Detector resolution: 0 pixels mm-1	θmax = 25.1°, θmin = 2.2°
φ and ω scans	h = −8→11
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	k = −11→11
Tmin = 0.095, Tmax = 0.241	l = −10→11
2584 measured reflections

Refinement

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)] = 0.044	Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.127	H-atom parameters constrained
S = 1.00	w = 1/[σ2(Fo2) + (0.081P)2 + 5.867P] where P = (Fo2 + 2Fc2)/3
1515 reflections	(Δ/σ)max = 0.012
118 parameters	Δρmax = 1.09 e Å−3
0 restraints	Δρmin = −0.93 e Å−3

Special details

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 (Ų)

	x	y	z	Uiso*/Ueq
Cu1	0.49099 (7)	0.34456 (6)	0.41130 (7)	0.0175 (2)
N1	0.2180 (5)	0.4606 (4)	0.3842 (5)	0.0152 (9)
O1	0.3577 (4)	0.4929 (4)	0.4067 (4)	0.0184 (8)
O2	0.4245 (4)	0.2618 (4)	0.5602 (4)	0.0256 (9)
O3	0.2807 (5)	0.2489 (5)	0.6967 (5)	0.0294 (10)
C1	0.1845 (6)	0.3627 (6)	0.4668 (6)	0.0193 (12)
C2	0.0387 (7)	0.3350 (6)	0.4398 (7)	0.0238 (13)
H2A	0.0140	0.2691	0.4987	0.029*
C3	−0.0713 (6)	0.4001 (7)	0.3300 (7)	0.0315 (15)
H3A	−0.1715	0.3771	0.3092	0.038*
C4	−0.0343 (7)	0.5010 (7)	0.2490 (8)	0.0338 (15)
H4A	−0.1092	0.5496	0.1744	0.041*
C5	0.1116 (7)	0.5293 (6)	0.2782 (7)	0.0259 (13)
H5A	0.1377	0.5978	0.2232	0.031*
C6	0.3066 (6)	0.2862 (5)	0.5851 (6)	0.0180 (11)
Br1	0.67758 (6)	0.17677 (6)	0.45034 (7)	0.0260 (2)
O4	0.5513 (4)	0.4396 (4)	0.2586 (4)	0.0216 (8)
H4B2	0.5328	0.3904	0.1812	0.032*
H4B1	0.4763	0.4764	0.1945	0.032*

Atomic displacement parameters (Ų)

	U11	U22	U33	U12	U13	U23
Cu1	0.0175 (4)	0.0176 (4)	0.0202 (4)	0.0022 (2)	0.0101 (3)	0.0019 (2)
N1	0.013 (2)	0.015 (2)	0.018 (2)	0.0020 (16)	0.0062 (18)	0.0016 (17)
O1	0.0139 (19)	0.0198 (19)	0.023 (2)	−0.0029 (14)	0.0085 (16)	−0.0027 (15)
O2	0.023 (2)	0.030 (2)	0.028 (2)	0.0079 (18)	0.0140 (19)	0.0088 (18)
O3	0.031 (2)	0.037 (2)	0.027 (2)	0.0078 (19)	0.0185 (19)	0.0154 (19)
C1	0.023 (3)	0.018 (3)	0.018 (3)	−0.001 (2)	0.009 (2)	−0.002 (2)
C2	0.019 (3)	0.025 (3)	0.028 (3)	−0.003 (2)	0.009 (3)	−0.002 (2)
C3	0.015 (3)	0.042 (4)	0.034 (4)	−0.005 (3)	0.005 (3)	−0.004 (3)
C4	0.024 (3)	0.039 (4)	0.033 (3)	0.008 (3)	0.003 (3)	0.007 (3)
C5	0.023 (3)	0.028 (3)	0.024 (3)	0.004 (2)	0.005 (2)	0.007 (2)
C6	0.019 (3)	0.016 (3)	0.019 (3)	0.000 (2)	0.006 (2)	0.001 (2)
Br1	0.0240 (4)	0.0251 (4)	0.0299 (4)	0.0071 (2)	0.0110 (3)	0.0003 (2)
O4	0.021 (2)	0.025 (2)	0.018 (2)	−0.0014 (16)	0.0058 (16)	−0.0016 (16)

Geometric parameters (Å, °)

Cu1—O2	1.938 (4)	C1—C6	1.520 (8)
Cu1—O1	1.963 (4)	C2—C3	1.365 (9)
Cu1—O4	1.990 (4)	C2—H2A	0.9500
Cu1—Br1	2.4034 (8)	C3—C4	1.393 (10)
N1—O1	1.336 (6)	C3—H3A	0.9500
N1—C5	1.348 (7)	C4—C5	1.373 (9)
N1—C1	1.366 (7)	C4—H4A	0.9500
O2—C6	1.272 (7)	C5—H5A	0.9500
O3—C6	1.232 (7)	O4—H4B2	0.8500
C1—C2	1.375 (8)	O4—H4B1	0.8500
O2—Cu1—O1	87.31 (16)	C1—C2—H2A	119.3
O2—Cu1—O4	176.34 (17)	C2—C3—C4	119.0 (6)
O1—Cu1—O4	89.04 (16)	C2—C3—H3A	120.5
O2—Cu1—Br1	90.90 (12)	C4—C3—H3A	120.5
O1—Cu1—Br1	171.71 (12)	C5—C4—C3	119.3 (6)
O4—Cu1—Br1	92.68 (12)	C5—C4—H4A	120.4
O1—N1—C5	117.5 (4)	C3—C4—H4A	120.4
O1—N1—C1	121.2 (4)	N1—C5—C4	120.5 (6)
C5—N1—C1	121.4 (5)	N1—C5—H5A	119.8
N1—O1—Cu1	116.3 (3)	C4—C5—H5A	119.8
C6—O2—Cu1	127.5 (4)	O3—C6—O2	125.1 (5)
N1—C1—C2	118.5 (5)	O3—C6—C1	116.4 (5)
N1—C1—C6	120.3 (5)	O2—C6—C1	118.5 (5)
C2—C1—C6	121.1 (5)	Cu1—O4—H4B2	109.1
C3—C2—C1	121.3 (6)	Cu1—O4—H4B1	109.3
C3—C2—H2A	119.3	H4B2—O4—H4B1	76.6
C5—N1—O1—Cu1	−131.2 (4)	C1—C2—C3—C4	−3.0 (10)
C1—N1—O1—Cu1	49.5 (5)	C2—C3—C4—C5	2.1 (10)
O2—Cu1—O1—N1	−52.2 (3)	O1—N1—C5—C4	179.8 (5)
O4—Cu1—O1—N1	128.0 (3)	C1—N1—C5—C4	−0.9 (9)
O1—Cu1—O2—C6	20.4 (5)	C3—C4—C5—N1	−0.1 (10)
Br1—Cu1—O2—C6	−167.7 (5)	Cu1—O2—C6—O3	−166.6 (4)
O1—N1—C1—C2	179.2 (5)	Cu1—O2—C6—C1	15.8 (7)
C5—N1—C1—C2	0.0 (8)	N1—C1—C6—O3	147.3 (5)
O1—N1—C1—C6	−1.1 (7)	C2—C1—C6—O3	−33.0 (8)
C5—N1—C1—C6	179.6 (5)	N1—C1—C6—O2	−34.8 (8)
N1—C1—C2—C3	2.0 (9)	C2—C1—C6—O2	144.8 (6)
C6—C1—C2—C3	−177.7 (6)

Hydrogen-bond geometry (Å, °)

D—H···A	D—H	H···A	D···A	D—H···A
O4—H4B2···O2i	0.85	1.97	2.738 (5)	149
O4—H4B2···Br1i	0.85	3.07	3.741 (4)	137
O4—H4B1···Br1ii	0.85	2.59	3.377 (4)	155

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