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

Journal logoCRYSTALLOGRAPHIC
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ISSN: 2056-9890
Volume 65| Part 3| March 2009| Pages m303-m304

catena-Poly[[(pyridine-κN)copper(II)]-μ3-pyridine-2,6-di­carboxylato-κ3O2:O2′,N,O6:O6′]

aDepartment of Chemistry, Faculty of Science, Banaras Hindu University, Varanasi 221005, India, and bDepartment of Chemistry and Biochemistry, and Centre for Nanoscience, University of Missouri-St Louis, One University Boulevard, St Louis, MO 63121-4499, USA
*Correspondence e-mail: manojtri@gmail.com

(Received 20 January 2009; accepted 13 February 2009; online 21 February 2009)

In the title compound, [Cu(C7H3NO4)(C5H5N)]n, the CuII atom is in a slightly distorted octa­hedral coordination environment. Each CuII atom is bound to two N atoms and one O atom of the pyridine­dicarboxyl­ate (PDA) ligand in a tridentate manner, one N atom of the pyridine mol­ecule and two bridging carboxyl­ate O atoms of adjacent PDA ligands, leading to a linear one-dimensional chain running along the c axis. These chains are further assembled via weak C—H⋯O and ππ inter­actions into a three-dimensional supra­molecular network structure. The centroid–centroid distance between the ππ inter­acting pyridine rings is 3.9104 (13) Å. The two N atoms are trans to each other with respect to Cu.

Related literature

For background information on coordination polymers, see: Kitagawa et al. (2004[Kitagawa, S., Kitaura, R. & Noro, S. (2004). Angew. Chem. Int. Ed. 43, 2334-2375.]); Kirillov et al. (2008[Kirillov, A. M., Karabach, Y. Y., Haukka, M., Guedes da Silva, M. F. C., Sanchiz, J., Kopylovich, M. N. & Pombeiro, A. J. L. (2008). Inorg. Chem. 47, 162-175.]); Hoskins & Robson (1990[Hoskins, B. F. & Robson, R. (1990). J. Am. Chem. Soc. 112, 1546-1554.]); Eddaoudi et al. (2001[Eddaoudi, M., Moler, D. B., Li, H., Chen, B., Reineke, T. M., OKeeffe, M. & Yaghi, O. M. (2001). Acc. Chem. Res. 34, 319-330.]). For related polymeric structures of PDA complexes, see, for example: Zhao et al. (2003[Zhao, B., Cheng, P., Dai, Y., Cheng, C., Liao, D.-Z., Yan, S.-P., Jiang, Z.-H. & Wang, G.-L. (2003). Angew. Chem. Int. Ed. 42, 934-936.]); Choi et al. (2003[Choi, K.-Y., Ryu, H., Lim, Y.-M., Sung, N.-D., Shin, U.-S. & Suh, M. (2003). Inorg. Chem. Commun. 6, 412-415.]); Ghosh et al. (2004[Ghosh, S. K., Ribas, J. & Bharadwaj, P. K. (2004). CrystEngComm, 6, 250-256.]); Xie et al. (2004[Xie, C., Zhang, Z., Wang, X., Liu, X., Shen, G., Wang, R. & Shen, D. (2004). J. Coord. Chem. 57, 1173-1178.]). For related structures of Cu complexes, see: Uçar et al. (2007[Uçar, İ., Karabulut, B., Bulut, A. & Büyükgüngör, O. (2007). J. Mol. Struct. 834-836, 336-344.]); Manna et al. (2007[Manna, S. C., Ribas, J., Zangrando, E. & Chaudhuri, N. R. (2007). Inorg. Chim. Acta, 360, 2589-2597.]); Gao et al. (2006[Gao, H.-L., Yi, L., Zhao, B., Zhao, X.-Q., Cheng, P., Liao, D.-Z. & Yan, S.-P. (2006). Inorg. Chem. 45, 5980-5988.]).

[Scheme 1]

Experimental

Crystal data
  • [Cu(C7H3NO4)(C5H5N)]

  • Mr = 307.74

  • Monoclinic, C 2/c

  • a = 7.8042 (9) Å

  • b = 13.6152 (17) Å

  • c = 10.0667 (12) Å

  • β = 91.687 (4)°

  • V = 1069.2 (2) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 2.06 mm−1

  • T = 100 K

  • 0.21 × 0.13 × 0.08 mm

Data collection
  • Bruker APEXII CCD area-detector diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2007[Bruker (2007). SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.671, Tmax = 0.848

  • 3530 measured reflections

  • 981 independent reflections

  • 859 reflections with I > 2σ(I)

  • Rint = 0.036

Refinement
  • R[F2 > 2σ(F2)] = 0.029

  • wR(F2) = 0.074

  • S = 1.10

  • 981 reflections

  • 89 parameters

  • H-atom parameters not refined

  • Δρmax = 0.41 e Å−3

  • Δρmin = −0.60 e Å−3

Table 1
Selected bond lengths (Å)

Cu1—N2 1.896 (3)
Cu1—N1 1.944 (3)
Cu1—O1 2.0110 (18)
Cu1—O1i 2.0110 (18)
Symmetry code: (i) [-x+1, y, -z+{\script{1\over 2}}].

Table 2
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
C3—H3⋯O2ii 0.95 2.44 3.187 (3) 135
C5—H5⋯O1i 0.95 2.48 3.070 (3) 120
C6—H6⋯O1iii 0.95 2.48 3.394 (3) 162
Symmetry codes: (i) [-x+1, y, -z+{\script{1\over 2}}]; (ii) [-x+{\script{1\over 2}}, -y-{\script{1\over 2}}, -z]; (iii) [x+{\script{1\over 2}}, -y+{\script{1\over 2}}, z+{\script{1\over 2}}].

Supporting information


Comment top

The rapidly expanding field of the crystal engineering (the design of crystalline materials) of polymeric coordination networks stems has recently attracted great interest because of their potential applications as zeolite-like materials for molecular selection, ion exchange, and catalysis, as well as in the variety of architectures and topologies (Kitagawa et al., 2004; Kirillov et al., 2008). The main strategy popularly used in this area is a building-block approach (Hoskins & Robson, 1990; Eddaoudi et al., 2001). 2,6-Pyridinedicarboxylic acid (H2PDA) is an efficient ligand. Polymeric structure of PDA complexes with transition and lanthanide metals have been reported, in which PDA not only chelates but also bridges to form diversified structures with three coordination sites (Zhao et al., 2003; Choi et al., 2003; Ghosh et al., 2004; Xie et al., 2004). We report the synthesis, and crystal structures of one compound, [Cu(µ-2,6-PDA)(py)]n, (1).

Molecular structure of (1) shows a slightly distorted octahedral coordination geometry. The equatorial sites are occupied by an NO2 donor from the carboxylate groups at the pyridine-2,6-position of PDA (N2, O1, O1i) and one N atom from pyridine (N1). Two O atoms from two other neighboring PDA ligands occupy the axial sites (O2, O2i) at a distance of 2.761 Å (Fig. 1). The equatorial Cu—O and Cu—N bond lengths of are normal [Cu1—O1 = 2.0110 (18) Å, Cu1—O1i = 2.0110 (18) Å, Cu1—N2 = 1.896 (3) Å, Cu1—N1 = 1.944 (3) Å], which are within ranges reported in other copper complexes (Uçar et al., 2007; Manna et al., 2007; Gao et al., 2006). The pyridine is essentially planar with no deviation from planarity for pyridyl N1-atom. The C—C—C angles about the pyridyl ring are 118.2 (3) to 128.5 (2)°, indicating sp2 hybridization. Two carboxylate O atoms (O2 and O2i) which are coordinated to the adjacent copper atom, have C—O distances [O2—C1 = 1.228 (3) Å, O1—C1 = 1.290 (3) Å] which are generally shorter than C—O distances, indicating the conjugation of the double bond after deprotonation. In this way, the PDA ligands bridge adjacent Cu atoms to form a [Cu(µ-2,6-PDC)(py)]n linear chains extending in the [001] direction (Fig. 2). The separations between the two Cu atom in the linear chains are 5.332 Å. The PDA ligand and pyridine are trans to each other (N2—Cu1—N1 = 180°). However, one-dimensional polymeric chains are connected in the solid state through weak C—H···O and π-π interactions. Weak C—H···O interactions that connects polymeric chains into two-dimensional network (Fig. 3). Contact distances for C—H···O interactions are 2.43–2.76 Å (Table 1). The weak π-π interactions are present in (1). Further, the importance of π-π stacking interactions between aromatic rings has widely been recognized in the intercalation of drugs with DNA especially in biological systems, which lie in the range 3.4–3.5 Å. The complex (1) exhibits intermolecular face-to-face π-π interactions [π-pyridyl/π-pyridyl ct/ct distance 3.9104 (13) Å; Fig. 4].

Related literature top

For background information on coordination polymers, see: Kitagawa et al. (2004); Kirillov et al. (2008); Hoskins & Robson (1990); Eddaoudi et al. (2001). For related polymeric structures of PDA complexes, see, for example: Zhao et al. (2003); Choi et al. (2003); Ghosh et al. (2004); Xie et al. (2004). For related structures of Cu complexes, see: Uçar et al. (2007); Manna et al. (2007); Gao et al. (2006).

Experimental top

A mixture of [Cu(NO3)2.6H2O] (0.466 g, 2 mmol), H2PDA (0.167 g, 1 mmol), 2-Pyridine thiol(0.111 g, 1 mmol) was dissolved in a mixture of MeOH (5 ml) and water (5 mL) and add pyridine (in excess). The solution was stirred for 24 h at room temperature. Slowly, color of the solution changes from blue to dark green. The resulting solution was filtered and left at room temperature for two days, which resulted in blue needle crystals which are suitable for X-ray diffraction analysis (yield 0.184 g, 60%). Anal. Calc. for C12H8N2O4Cu: C 48.83, H 2.62, N 9.10%; found: C 47.65, H 2.56, N 9.30%.

Refinement top

All H atoms were added in their calculated positions (C—H = 0.95 Å) and were treated using appropriate riding models, with Uiso(H) = 1.2Ueq(C).

Computing details top

Data collection: APEX2 (Bruker, 2006); cell refinement: SAINT (Bruker, 2006); data reduction: SAINT (Bruker, 2006); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. A view of the structure of (1), showing the atom-numbering scheme and the Cu coordination octahedra; displacement ellipsoids are drawn at the 50% probability level.
[Figure 2] Fig. 2. Packing view of (1), showing linear chains along the [001] direction.
[Figure 3] Fig. 3. Packing view of (1), showing connectivity with other polymeric chains through weak C—H···O hydrogen bond interactions.
[Figure 4] Fig. 4. Packing view of (1), showing face-to-face π-π interactions.
catena-Poly[[(pyridine-κN)copper(II)]-µ3-pyridine-2,6- dicarboxylato-κ3O2:O2',N,O6:O6'] top
Crystal data top
[Cu(C7H3NO4)(C5H5N)]F(000) = 620
Mr = 307.74Dx = 1.912 Mg m3
Monoclinic, C2/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2ycCell parameters from 1607 reflections
a = 7.8042 (9) Åθ = 3.0–25.3°
b = 13.6152 (17) ŵ = 2.06 mm1
c = 10.0667 (12) ÅT = 100 K
β = 91.687 (4)°Needle, blue
V = 1069.2 (2) Å30.21 × 0.13 × 0.08 mm
Z = 4
Data collection top
Bruker APEXII CCD area-detector
diffractometer
981 independent reflections
Radiation source: fine-focus sealed tube859 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.036
ϕ and ω scansθmax = 25.3°, θmin = 3.0°
Absorption correction: multi-scan
(SADABS; Bruker, 2007)
h = 98
Tmin = 0.671, Tmax = 0.848k = 1616
3530 measured reflectionsl = 1211
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)] = 0.029Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.074H-atom parameters not refined
S = 1.10 w = 1/[σ2(Fo2) + (0.0347P)2 + 1.5139P]
where P = (Fo2 + 2Fc2)/3
981 reflections(Δ/σ)max < 0.001
89 parametersΔρmax = 0.41 e Å3
0 restraintsΔρmin = 0.60 e Å3
Crystal data top
[Cu(C7H3NO4)(C5H5N)]V = 1069.2 (2) Å3
Mr = 307.74Z = 4
Monoclinic, C2/cMo Kα radiation
a = 7.8042 (9) ŵ = 2.06 mm1
b = 13.6152 (17) ÅT = 100 K
c = 10.0667 (12) Å0.21 × 0.13 × 0.08 mm
β = 91.687 (4)°
Data collection top
Bruker APEXII CCD area-detector
diffractometer
981 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2007)
859 reflections with I > 2σ(I)
Tmin = 0.671, Tmax = 0.848Rint = 0.036
3530 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0290 restraints
wR(F2) = 0.074H-atom parameters not refined
S = 1.10Δρmax = 0.41 e Å3
981 reflectionsΔρmin = 0.60 e Å3
89 parameters
Special details top

Experimental. All H atoms were added in their calculated positions and were treated using appropriate riding models.

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*/Ueq
Cu10.50000.06463 (3)0.25000.01055 (18)
O10.3461 (2)0.04164 (13)0.08928 (18)0.0119 (4)
O20.2652 (2)0.07906 (13)0.05100 (19)0.0137 (4)
N10.50000.2074 (2)0.25000.0099 (7)
N20.50000.0746 (2)0.25000.0096 (7)
C10.3334 (3)0.04888 (19)0.0526 (3)0.0111 (6)
C20.4161 (3)0.1210 (2)0.1514 (3)0.0100 (6)
C30.4135 (3)0.2221 (2)0.1484 (3)0.0120 (6)
H30.35420.25640.07890.014*
C40.50000.2728 (3)0.25000.0130 (8)
H40.50000.34260.25000.016*
C50.5748 (3)0.2583 (2)0.3507 (3)0.0124 (6)
H50.62860.22300.42180.015*
C60.5765 (4)0.3594 (2)0.3549 (3)0.0154 (6)
H60.62900.39310.42810.018*
C70.50000.4112 (3)0.25000.0159 (9)
H70.50000.48100.25000.019*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cu10.0144 (3)0.0059 (3)0.0109 (3)0.0000.00649 (18)0.000
O10.0151 (10)0.0074 (10)0.0129 (10)0.0014 (8)0.0066 (8)0.0000 (8)
O20.0173 (10)0.0117 (11)0.0118 (10)0.0026 (8)0.0068 (8)0.0017 (8)
N10.0095 (16)0.0095 (17)0.0108 (17)0.0000.0009 (13)0.000
N20.0085 (16)0.0102 (17)0.0100 (16)0.0000.0009 (13)0.000
C10.0114 (14)0.0106 (14)0.0114 (15)0.0017 (11)0.0007 (11)0.0004 (11)
C20.0080 (13)0.0125 (15)0.0095 (14)0.0020 (11)0.0011 (11)0.0023 (11)
C30.0122 (14)0.0131 (15)0.0108 (14)0.0006 (11)0.0019 (11)0.0018 (11)
C40.014 (2)0.009 (2)0.016 (2)0.0000.0001 (16)0.000
C50.0124 (14)0.0138 (15)0.0110 (15)0.0001 (11)0.0012 (11)0.0007 (11)
C60.0163 (15)0.0136 (15)0.0163 (16)0.0035 (12)0.0025 (12)0.0042 (12)
C70.016 (2)0.009 (2)0.023 (2)0.0000.0055 (17)0.000
Geometric parameters (Å, º) top
Cu1—N21.896 (3)C2—C31.378 (4)
Cu1—N11.944 (3)C3—C41.392 (3)
Cu1—O12.0110 (18)C3—H30.9500
Cu1—O1i2.0110 (18)C4—C3i1.392 (3)
O1—C11.290 (3)C4—H40.9500
O2—C11.228 (3)C5—C61.378 (4)
N1—C5i1.347 (3)C5—H50.9500
N1—C51.347 (3)C6—C71.390 (3)
N2—C21.332 (3)C6—H60.9500
N2—C2i1.332 (3)C7—C6i1.390 (3)
C1—C21.527 (4)C7—H70.9500
N2—Cu1—N1180.0N2—C2—C1111.7 (2)
N2—Cu1—O181.05 (5)C3—C2—C1128.5 (2)
N1—Cu1—O198.95 (5)C2—C3—C4118.2 (3)
N2—Cu1—O1i81.05 (5)C2—C3—H3120.9
N1—Cu1—O1i98.95 (5)C4—C3—H3120.9
O1—Cu1—O1i162.10 (10)C3—C4—C3i120.6 (4)
C1—O1—Cu1114.71 (16)C3—C4—H4119.7
C5i—N1—C5118.1 (3)C3i—C4—H4119.7
C5i—N1—Cu1120.97 (16)N1—C5—C6122.8 (3)
C5—N1—Cu1120.96 (16)N1—C5—H5118.6
C2—N2—C2i123.4 (3)C6—C5—H5118.6
C2—N2—Cu1118.28 (16)C5—C6—C7118.7 (3)
C2i—N2—Cu1118.28 (16)C5—C6—H6120.7
O2—C1—O1126.2 (2)C7—C6—H6120.7
O2—C1—C2120.2 (2)C6i—C7—C6119.0 (4)
O1—C1—C2113.6 (2)C6i—C7—H7120.5
N2—C2—C3119.8 (3)C6—C7—H7120.5
N2—Cu1—O1—C16.98 (18)Cu1—N2—C2—C3179.96 (18)
N1—Cu1—O1—C1173.02 (18)C2i—N2—C2—C1179.7 (2)
O1i—Cu1—O1—C16.98 (18)Cu1—N2—C2—C10.3 (2)
O1—Cu1—N1—C5i6.84 (14)O2—C1—C2—N2172.9 (2)
O1i—Cu1—N1—C5i173.16 (14)O1—C1—C2—N26.2 (3)
O1—Cu1—N1—C5173.16 (14)O2—C1—C2—C36.8 (4)
O1i—Cu1—N1—C56.84 (14)O1—C1—C2—C3174.1 (3)
O1—Cu1—N2—C23.29 (14)N2—C2—C3—C40.1 (4)
O1i—Cu1—N2—C2176.71 (14)C1—C2—C3—C4179.6 (2)
O1—Cu1—N2—C2i176.71 (14)C2—C3—C4—C3i0.03 (18)
O1i—Cu1—N2—C2i3.29 (14)C5i—N1—C5—C60.47 (19)
Cu1—O1—C1—O2170.2 (2)Cu1—N1—C5—C6179.53 (19)
Cu1—O1—C1—C28.8 (3)N1—C5—C6—C70.9 (4)
C2i—N2—C2—C30.04 (18)C5—C6—C7—C6i0.44 (18)
Symmetry code: (i) x+1, y, z+1/2.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C3—H3···O2ii0.952.443.187 (3)135
C5—H5···O1i0.952.483.070 (3)120
C6—H6···O1iii0.952.483.394 (3)162
Symmetry codes: (i) x+1, y, z+1/2; (ii) x+1/2, y1/2, z; (iii) x+1/2, y+1/2, z+1/2.

Experimental details

Crystal data
Chemical formula[Cu(C7H3NO4)(C5H5N)]
Mr307.74
Crystal system, space groupMonoclinic, C2/c
Temperature (K)100
a, b, c (Å)7.8042 (9), 13.6152 (17), 10.0667 (12)
β (°) 91.687 (4)
V3)1069.2 (2)
Z4
Radiation typeMo Kα
µ (mm1)2.06
Crystal size (mm)0.21 × 0.13 × 0.08
Data collection
DiffractometerBruker APEXII CCD area-detector
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 2007)
Tmin, Tmax0.671, 0.848
No. of measured, independent and
observed [I > 2σ(I)] reflections
3530, 981, 859
Rint0.036
(sin θ/λ)max1)0.602
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.029, 0.074, 1.10
No. of reflections981
No. of parameters89
H-atom treatmentH-atom parameters not refined
Δρmax, Δρmin (e Å3)0.41, 0.60

Computer programs: APEX2 (Bruker, 2006), SAINT (Bruker, 2006), SHELXTL (Sheldrick, 2008).

Selected bond lengths (Å) top
Cu1—N21.896 (3)Cu1—O12.0110 (18)
Cu1—N11.944 (3)Cu1—O1i2.0110 (18)
Symmetry code: (i) x+1, y, z+1/2.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C3—H3···O2ii0.952.443.187 (3)135
C5—H5···O1i0.952.483.070 (3)120
C6—H6···O1iii0.952.483.394 (3)162
Symmetry codes: (i) x+1, y, z+1/2; (ii) x+1/2, y1/2, z; (iii) x+1/2, y+1/2, z+1/2.
 

Footnotes

Present Address: Department of Chemistry, University of Delhi, Delhi 110007, India.

Acknowledgements

The authors gratefully acknowledge financial support by the Council of Scientific and Industrial Research, New Delhi, and the University Grants Commission, New Delhi [grant No. F.4-2/2006(BSR)/13-76/2008(BSR)]. The authors also thank Dr Rajamani Nagarajan and the Head, Department of Chemistry, University of Delhi, and the Head, Department of Chemistry, Faculty of Science, Banaras Hindu University, Varanasi, for their support. Funding from the National Science Foundation (grant No. CHE0420497) for the purchase of the APEXII diffractometer is acknowledged.

References

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Volume 65| Part 3| March 2009| Pages m303-m304
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