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

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 65| Part 1| January 2009| Pages m45-m46

Aquabis­(6-bromo­picolinato-κ2N,O)copper(II)

aCollege of Chemistry and Ecological Engineering, Guangxi University for Nationalities, Nanning 530006, People's Republic of China
*Correspondence e-mail: yxhphd@163.com

(Received 4 December 2008; accepted 8 December 2008; online 10 December 2008)

In the title compound, [Cu(C6H3BrNO2)2(H2O)], the Cu atom adopts a distorted trigonal-bipyramidal coordination arising from two N,O-bidentate ligands and a water mol­ecule, with one N atom in an axial site and the other in an equatorial site. The dihedral angle between the pyridine ring planes is 67.6 (2)°. In the crystal, O—H⋯O hydrogen bonds result in chains propagating in [100].

Related literature

For background, see: Mann et al. (1992[Mann, Y., Chiment, F., Balasco, A., Cenicola, M. L., Amico, M. D., Parrilo, C., Rossi, F. & Marmo, E. (1992). Eur. J. Med. Chem. 27, 633-639.]).

[Scheme 1]

Experimental

Crystal data
  • [Cu(C6H3BrNO2)2(H2O)]

  • Mr = 483.56

  • Triclinic, [P \overline 1]

  • a = 6.9447 (8) Å

  • b = 9.1350 (10) Å

  • c = 11.4510 (13) Å

  • α = 86.741 (2)°

  • β = 84.056 (2)°

  • γ = 76.728 (1)°

  • V = 702.84 (14) Å3

  • Z = 2

  • Mo Kα radiation

  • μ = 7.26 mm−1

  • T = 298 (2) K

  • 0.18 × 0.14 × 0.08 mm

Data collection
  • Siemens SMART CCD diffractometer

  • Absorption correction: multi-scan (SADABS; Sheldrick, 1996[Sheldrick, G. M. (1996). SADABS. University of Göttingen, Germany.]) Tmin = 0.354, Tmax = 0.594 (expected range = 0.333–0.559)

  • 3669 measured reflections

  • 2435 independent reflections

  • 2137 reflections with I > 2σ(I)

  • Rint = 0.018

Refinement
  • R[F2 > 2σ(F2)] = 0.032

  • wR(F2) = 0.082

  • S = 1.02

  • 2435 reflections

  • 199 parameters

  • H-atom parameters constrained

  • Δρmax = 0.61 e Å−3

  • Δρmin = −0.59 e Å−3

Table 1
Selected bond lengths (Å)

Cu1—O1 1.912 (3)
Cu1—N2 1.985 (3)
Cu1—O5 2.022 (3)
Cu1—O3 2.072 (3)
Cu1—N1 2.148 (3)

Table 2
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
O5—H5A⋯O1i 0.85 1.93 2.765 (4) 168
O5—H5B⋯O4ii 0.85 1.90 2.743 (4) 169
Symmetry codes: (i) -x+1, -y, -z+2; (ii) x+1, y, z.

Data collection: SMART (Siemens, 1996[Siemens (1996). SMART and SAINT. Siemens Analytical X-Ray Systems, Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Siemens, 1996[Siemens (1996). SMART and SAINT. Siemens Analytical X-Ray Systems, 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

The chemical and pharmacological properties of pyridine derivatives have been investigated extensively, owing to their chelating ability with metal ions and their potentially beneficial chemical and biological activities (e.g. Mann et al., 1992). As part of our studies on the synthesis and characterization of these compounds, we report here the synthesis and crystal structure of the title compound, (I), (Fig. 1).

The copper centre in (I) adopts distorted trigonal biyramid coordination geometry by being coordinated with two nitrogen atoms from the pyridine rings and three oxygen atoms from the ligands (Table 1). The dihedral angle of the two pyridine rings is 67.6 (2)°.

Analysis of the crystal packing of the title compound reveals the existence of intermolecular O—H···O hydrogen bonds between the carboxyl oxygen atoms and coordinated water molecule (Fig. 2), forming a one-dimensional chain parallel to the a-axis. The coordinated water molecule acts as a hydrogen-bond donor towards O1 and O4 of the adjacent complexes (Table 2), the carboxylate group that acts as an H bond acceptor towards the O5 via both of its O atoms O4 and O3 exhibits a delocalized π system with nearly identical C—O distances.

Related literature top

For background, see: Mann et al. (1992).

Experimental top

1 mmol (200.9 mg) of 6-bromopicolinic acid was added to 0.5 mmol (132 mg) of CuCl2 in 10 ml of anhydrous alcohol. The suspension was stirred for ca 4 h and filtered. After keeping the filtrate in air for one week, blue blocks of (I) precipitated. The crystals were isolated, washed with alcohol three times and dried in a vacuum desiccator using silica gel (Yield 75%). Elemental analysis: found C, 29.79; H, 1.68; N, 5.78; calc. for C12H8N2Br3O5Cu: C, 29.81; H, 1.67; N, 5.79.

Refinement top

The H atoms were positoned geometrically (C—H = 0.93Å, O—H = 0.85Å) and refined as riding with Uiso(H) = 1.2Ueq(C) or 1.5Ueq(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 molecular structure of (I) showing 30% probability displacement ellipsoids for the non-hydrogen atoms.
[Figure 2] Fig. 2. Part of the hydrogen bonding network, the hydrogen bonded interactions are showing as dashed lines. [symmetry codes: (I) -1+x, y, z; (II) 1-x, -y, 2-z; (III) 2-x, 1-y, 1-z; (IV) x, 1+y, -1+z; (V) 1-x, 1-y, 1-z.]
Aquabis(6-bromopicolinato-κ2N,O)copper(II) top
Crystal data top
[Cu(C6H3BrNO2)2(H2O)]Z = 2
Mr = 483.56F(000) = 466
Triclinic, P1Dx = 2.285 Mg m3
Hall symbol: -P 1Mo Kα radiation, λ = 0.71073 Å
a = 6.9447 (8) ÅCell parameters from 2146 reflections
b = 9.135 (1) Åθ = 2.3–28.1°
c = 11.4510 (13) ŵ = 7.26 mm1
α = 86.741 (2)°T = 298 K
β = 84.056 (2)°Block, blue
γ = 76.728 (1)°0.18 × 0.14 × 0.08 mm
V = 702.84 (14) Å3
Data collection top
Siemens SMART CCD
diffractometer
2435 independent reflections
Radiation source: fine-focus sealed tube2137 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.018
ω scansθmax = 25.0°, θmin = 1.8°
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
h = 78
Tmin = 0.354, Tmax = 0.594k = 910
3669 measured reflectionsl = 1312
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)] = 0.032Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.082H-atom parameters constrained
S = 1.02 w = 1/[σ2(Fo2) + (0.0433P)2 + 0.8458P]
where P = (Fo2 + 2Fc2)/3
2435 reflections(Δ/σ)max = 0.001
199 parametersΔρmax = 0.61 e Å3
0 restraintsΔρmin = 0.59 e Å3
Crystal data top
[Cu(C6H3BrNO2)2(H2O)]γ = 76.728 (1)°
Mr = 483.56V = 702.84 (14) Å3
Triclinic, P1Z = 2
a = 6.9447 (8) ÅMo Kα radiation
b = 9.135 (1) ŵ = 7.26 mm1
c = 11.4510 (13) ÅT = 298 K
α = 86.741 (2)°0.18 × 0.14 × 0.08 mm
β = 84.056 (2)°
Data collection top
Siemens SMART CCD
diffractometer
2435 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
2137 reflections with I > 2σ(I)
Tmin = 0.354, Tmax = 0.594Rint = 0.018
3669 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0320 restraints
wR(F2) = 0.082H-atom parameters constrained
S = 1.02Δρmax = 0.61 e Å3
2435 reflectionsΔρmin = 0.59 e Å3
199 parameters
Special details top

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds 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 > 2sigma(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
Cu10.36391 (7)0.20148 (5)0.83934 (4)0.02864 (15)
Br10.09458 (7)0.53067 (5)0.65643 (4)0.04093 (15)
Br20.66479 (7)0.36146 (5)0.64489 (4)0.04116 (15)
N10.2408 (5)0.4351 (4)0.8722 (3)0.0258 (7)
N20.3743 (5)0.1983 (3)0.6656 (3)0.0256 (7)
O10.3617 (5)0.1928 (3)1.0067 (2)0.0382 (7)
O20.3544 (5)0.3296 (4)1.1627 (3)0.0485 (8)
O30.1337 (4)0.0956 (4)0.8258 (3)0.0382 (7)
O40.0273 (4)0.0169 (3)0.6914 (3)0.0383 (7)
O50.6281 (5)0.0513 (4)0.8380 (3)0.0558 (10)
H5A0.64540.02030.88930.067*
H5B0.73770.05080.79720.067*
C10.3350 (6)0.3182 (5)1.0602 (3)0.0320 (9)
C20.2678 (5)0.4583 (5)0.9843 (3)0.0283 (9)
C30.2265 (6)0.6001 (5)1.0303 (4)0.0379 (10)
H30.24590.61181.10810.046*
C40.1558 (7)0.7247 (5)0.9590 (4)0.0417 (11)
H40.13240.82130.98710.050*
C50.1210 (6)0.7029 (5)0.8466 (4)0.0366 (10)
H50.07030.78390.79730.044*
C60.1633 (6)0.5563 (5)0.8081 (4)0.0294 (9)
C70.1021 (6)0.0759 (4)0.7223 (3)0.0281 (9)
C80.2405 (6)0.1316 (4)0.6261 (3)0.0276 (8)
C90.2250 (6)0.1216 (5)0.5081 (4)0.0346 (10)
H90.12920.07730.48310.042*
C100.3536 (7)0.1783 (5)0.4273 (4)0.0379 (10)
H100.34630.17120.34720.045*
C110.4922 (7)0.2450 (5)0.4658 (4)0.0364 (10)
H110.58120.28270.41280.044*
C120.4961 (6)0.2548 (4)0.5859 (3)0.0291 (9)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cu10.0328 (3)0.0302 (3)0.0214 (3)0.0060 (2)0.00068 (19)0.0041 (2)
Br10.0450 (3)0.0414 (3)0.0322 (2)0.0002 (2)0.00934 (19)0.00599 (19)
Br20.0424 (3)0.0467 (3)0.0401 (3)0.0234 (2)0.00604 (19)0.0080 (2)
N10.0249 (17)0.0264 (17)0.0248 (17)0.0051 (14)0.0008 (13)0.0021 (13)
N20.0277 (17)0.0233 (16)0.0234 (16)0.0040 (13)0.0016 (13)0.0044 (13)
O10.0517 (19)0.0355 (17)0.0216 (14)0.0001 (14)0.0030 (13)0.0073 (12)
O20.057 (2)0.066 (2)0.0218 (16)0.0124 (17)0.0057 (14)0.0033 (15)
O30.0424 (18)0.0476 (18)0.0292 (16)0.0242 (14)0.0046 (13)0.0029 (13)
O40.0373 (17)0.0439 (18)0.0385 (17)0.0202 (14)0.0019 (13)0.0003 (14)
O50.047 (2)0.055 (2)0.045 (2)0.0162 (17)0.0127 (16)0.0257 (17)
C10.025 (2)0.044 (3)0.026 (2)0.0064 (18)0.0013 (16)0.0013 (18)
C20.0190 (19)0.037 (2)0.028 (2)0.0062 (16)0.0037 (15)0.0031 (17)
C30.034 (2)0.045 (3)0.037 (2)0.012 (2)0.0014 (18)0.012 (2)
C40.038 (3)0.035 (2)0.054 (3)0.012 (2)0.004 (2)0.010 (2)
C50.030 (2)0.027 (2)0.049 (3)0.0039 (18)0.0033 (19)0.0047 (19)
C60.0221 (19)0.036 (2)0.029 (2)0.0073 (17)0.0015 (16)0.0054 (17)
C70.031 (2)0.023 (2)0.029 (2)0.0046 (16)0.0003 (16)0.0024 (16)
C80.031 (2)0.0210 (19)0.029 (2)0.0027 (16)0.0025 (16)0.0045 (16)
C90.041 (2)0.029 (2)0.034 (2)0.0060 (19)0.0069 (19)0.0024 (18)
C100.052 (3)0.040 (3)0.021 (2)0.012 (2)0.0041 (19)0.0040 (18)
C110.045 (3)0.032 (2)0.027 (2)0.0048 (19)0.0056 (18)0.0056 (18)
C120.028 (2)0.028 (2)0.029 (2)0.0033 (17)0.0007 (16)0.0046 (16)
Geometric parameters (Å, º) top
Cu1—O11.912 (3)C1—C21.514 (6)
Cu1—N21.985 (3)C2—C31.384 (6)
Cu1—O52.022 (3)C3—C41.387 (6)
Cu1—O32.072 (3)C3—H30.9300
Cu1—N12.148 (3)C4—C51.367 (7)
Br1—C61.889 (4)C4—H40.9300
Br2—C121.882 (4)C5—C61.391 (6)
N1—C61.330 (5)C5—H50.9300
N1—C21.351 (5)C7—C81.529 (6)
N2—C121.342 (5)C8—C91.377 (6)
N2—C81.348 (5)C9—C101.382 (6)
O1—C11.296 (5)C9—H90.9300
O2—C11.208 (5)C10—C111.371 (6)
O3—C71.257 (5)C10—H100.9300
O4—C71.239 (5)C11—C121.387 (6)
O5—H5A0.8499C11—H110.9300
O5—H5B0.8499
O1—Cu1—N2176.76 (12)C4—C3—H3120.4
O1—Cu1—O586.47 (13)C5—C4—C3118.8 (4)
N2—Cu1—O590.80 (13)C5—C4—H4120.6
O1—Cu1—O398.49 (13)C3—C4—H4120.6
N2—Cu1—O380.87 (13)C4—C5—C6118.2 (4)
O5—Cu1—O3111.31 (14)C4—C5—H5120.9
O1—Cu1—N181.11 (12)C6—C5—H5120.9
N2—Cu1—N1102.11 (12)N1—C6—C5124.4 (4)
O5—Cu1—N1139.28 (14)N1—C6—Br1118.9 (3)
O3—Cu1—N1108.83 (12)C5—C6—Br1116.6 (3)
C6—N1—C2116.5 (3)O4—C7—O3126.9 (4)
C6—N1—Cu1135.6 (3)O4—C7—C8117.7 (3)
C2—N1—Cu1107.6 (2)O3—C7—C8115.3 (4)
C12—N2—C8118.0 (3)N2—C8—C9122.1 (4)
C12—N2—Cu1127.6 (3)N2—C8—C7114.7 (3)
C8—N2—Cu1114.4 (3)C9—C8—C7123.2 (4)
C1—O1—Cu1118.1 (3)C8—C9—C10119.1 (4)
C7—O3—Cu1114.7 (3)C8—C9—H9120.4
Cu1—O5—H5A120.1C10—C9—H9120.4
Cu1—O5—H5B130.5C11—C10—C9119.6 (4)
H5A—O5—H5B109.1C11—C10—H10120.2
O2—C1—O1125.5 (4)C9—C10—H10120.2
O2—C1—C2119.8 (4)C10—C11—C12118.2 (4)
O1—C1—C2114.6 (3)C10—C11—H11120.9
N1—C2—C3122.8 (4)C12—C11—H11120.9
N1—C2—C1116.0 (3)N2—C12—C11122.9 (4)
C3—C2—C1121.2 (4)N2—C12—Br2116.4 (3)
C2—C3—C4119.1 (4)C11—C12—Br2120.5 (3)
C2—C3—H3120.4
O1—Cu1—N1—C6172.9 (4)O2—C1—C2—C30.5 (6)
N2—Cu1—N1—C67.5 (4)O1—C1—C2—C3177.7 (4)
O5—Cu1—N1—C6113.2 (4)N1—C2—C3—C40.5 (6)
O3—Cu1—N1—C676.9 (4)C1—C2—C3—C4176.8 (4)
O1—Cu1—N1—C213.3 (3)C2—C3—C4—C52.8 (6)
N2—Cu1—N1—C2166.3 (2)C3—C4—C5—C61.7 (6)
O5—Cu1—N1—C260.6 (3)C2—N1—C6—C54.0 (6)
O3—Cu1—N1—C2109.3 (2)Cu1—N1—C6—C5169.3 (3)
O1—Cu1—N2—C12103 (2)C2—N1—C6—Br1173.3 (3)
O5—Cu1—N2—C1270.2 (3)Cu1—N1—C6—Br113.4 (5)
O3—Cu1—N2—C12178.3 (3)C4—C5—C6—N11.9 (6)
N1—Cu1—N2—C1270.9 (3)C4—C5—C6—Br1175.5 (3)
O1—Cu1—N2—C878 (2)Cu1—O3—C7—O4179.4 (3)
O5—Cu1—N2—C8110.3 (3)Cu1—O3—C7—C80.8 (4)
O3—Cu1—N2—C81.2 (3)C12—N2—C8—C90.6 (5)
N1—Cu1—N2—C8108.6 (3)Cu1—N2—C8—C9179.0 (3)
N2—Cu1—O1—C1160 (2)C12—N2—C8—C7177.7 (3)
O5—Cu1—O1—C1127.0 (3)Cu1—N2—C8—C71.9 (4)
O3—Cu1—O1—C1122.0 (3)O4—C7—C8—N2178.3 (3)
N1—Cu1—O1—C114.1 (3)O3—C7—C8—N21.8 (5)
O1—Cu1—O3—C7176.6 (3)O4—C7—C8—C91.3 (6)
N2—Cu1—O3—C70.2 (3)O3—C7—C8—C9178.8 (4)
O5—Cu1—O3—C787.1 (3)N2—C8—C9—C101.6 (6)
N1—Cu1—O3—C7100.0 (3)C7—C8—C9—C10178.4 (4)
Cu1—O1—C1—O2170.2 (4)C8—C9—C10—C110.9 (6)
Cu1—O1—C1—C211.7 (5)C9—C10—C11—C120.8 (6)
C6—N1—C2—C32.8 (6)C8—N2—C12—C111.2 (6)
Cu1—N1—C2—C3172.3 (3)Cu1—N2—C12—C11179.3 (3)
C6—N1—C2—C1173.6 (3)C8—N2—C12—Br2174.8 (3)
Cu1—N1—C2—C111.2 (4)Cu1—N2—C12—Br24.7 (4)
O2—C1—C2—N1176.9 (4)C10—C11—C12—N21.9 (6)
O1—C1—C2—N11.2 (5)C10—C11—C12—Br2174.0 (3)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O5—H5A···O1i0.851.932.765 (4)168
O5—H5B···O4ii0.851.902.743 (4)169
Symmetry codes: (i) x+1, y, z+2; (ii) x+1, y, z.

Experimental details

Crystal data
Chemical formula[Cu(C6H3BrNO2)2(H2O)]
Mr483.56
Crystal system, space groupTriclinic, P1
Temperature (K)298
a, b, c (Å)6.9447 (8), 9.135 (1), 11.4510 (13)
α, β, γ (°)86.741 (2), 84.056 (2), 76.728 (1)
V3)702.84 (14)
Z2
Radiation typeMo Kα
µ (mm1)7.26
Crystal size (mm)0.18 × 0.14 × 0.08
Data collection
DiffractometerSiemens SMART CCD
diffractometer
Absorption correctionMulti-scan
(SADABS; Sheldrick, 1996)
Tmin, Tmax0.354, 0.594
No. of measured, independent and
observed [I > 2σ(I)] reflections
3669, 2435, 2137
Rint0.018
(sin θ/λ)max1)0.595
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.032, 0.082, 1.02
No. of reflections2435
No. of parameters199
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.61, 0.59

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

Selected bond lengths (Å) top
Cu1—O11.912 (3)Cu1—O32.072 (3)
Cu1—N21.985 (3)Cu1—N12.148 (3)
Cu1—O52.022 (3)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O5—H5A···O1i0.851.932.765 (4)168
O5—H5B···O4ii0.851.902.743 (4)169
Symmetry codes: (i) x+1, y, z+2; (ii) x+1, y, z.
 

Acknowledgements

The authors thank the National Natural Science Foundation of China (20761002), the Natural Science Foundation of Guangxi (0832080), the Ministry of Education, Science and Technology Key projects (205121) and the Science Foundation of the State Ethnic Affairs Commission (07GX05). This project was supported by the Open Fund of the Key Laboratory of Development & Application of Forest Chemicals of Guangxi (GXFC08–07), the Fund of the Talent Highland Research Program of Guangxi University, the Development Foundation of Guangxi Research Institute of the Chemical Industry, the Science Foundation of Guangxi University for Nationalities (0409032, 0409012, 0509ZD047) and the Innovation Project of Guangxi University for Nationalities (gxun-chx0876).

References

First citationMann, Y., Chiment, F., Balasco, A., Cenicola, M. L., Amico, M. D., Parrilo, C., Rossi, F. & Marmo, E. (1992). Eur. J. Med. Chem. 27, 633–639.  Google Scholar
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ISSN: 2056-9890
Volume 65| Part 1| January 2009| Pages m45-m46
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