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

Trivedi, M.; Pandey, D.S.; Rath, N.P.

doi:10.1107/S1600536809005212

metal-organic compounds

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ISSN: 2056-9890

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

doi:10.1107/S1600536809005212

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

Manoj Trivedi,^a ^*‡ Daya Shankar Pandey ^a and Nigam P. Rath ^b

^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 Cu^II atom is in a slightly distorted octahedral coordination environment. Each Cu^II 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 π–π interactions into a three-dimensional supramolecular network structure. The centroid–centroid distance between the π–π 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 ); 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

Crystal data

[Cu(C₇H₃NO₄)(C₅H₅N)]
M_r = 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 ) T_min = 0.671, T_max = 0.848
3530 measured reflections
981 independent reflections
859 reflections with I > 2σ(I)
R_int = 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
Δρ_max = 0.41 e Å⁻³
Δρ_min = −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	D⋯A	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

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536809005212/is2384sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536809005212/is2384Isup2.hkl

checkCIF report

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%.

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

	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.
	Fig. 2. Packing view of (1), showing linear chains along the [001] direction.
	Fig. 3. Packing view of (1), showing connectivity with other polymeric chains through weak C—H···O hydrogen bond interactions.
	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:O^2',N,O⁶:O^6'] top

Crystal data top

[Cu(C₇H₃NO₄)(C₅H₅N)]	F(000) = 620
M_r = 307.74	D_x = 1.912 Mg m⁻³
Monoclinic, C2/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2yc	Cell parameters from 1607 reflections
a = 7.8042 (9) Å	θ = 3.0–25.3°
b = 13.6152 (17) Å	µ = 2.06 mm⁻¹
c = 10.0667 (12) Å	T = 100 K
β = 91.687 (4)°	Needle, blue
V = 1069.2 (2) Å³	0.21 × 0.13 × 0.08 mm
Z = 4

Data collection top

Bruker APEXII CCD area-detector diffractometer	981 independent reflections
Radiation source: fine-focus sealed tube	859 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.036
ϕ and ω scans	θ_max = 25.3°, θ_min = 3.0°
Absorption correction: multi-scan (SADABS; Bruker, 2007)	h = −9→8
T_min = 0.671, T_max = 0.848	k = −16→16
3530 measured reflections	l = −12→11

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)] = 0.029	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.074	H-atom parameters not refined
S = 1.10	w = 1/[σ²(F_o²) + (0.0347P)² + 1.5139P] where P = (F_o² + 2F_c²)/3
981 reflections	(Δ/σ)_max < 0.001
89 parameters	Δρ_max = 0.41 e Å⁻³
0 restraints	Δρ_min = −0.60 e Å⁻³

Crystal data top

[Cu(C₇H₃NO₄)(C₅H₅N)]	V = 1069.2 (2) Å³
M_r = 307.74	Z = 4
Monoclinic, C2/c	Mo Kα radiation
a = 7.8042 (9) Å	µ = 2.06 mm⁻¹
b = 13.6152 (17) Å	T = 100 K
c = 10.0667 (12) Å	0.21 × 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)
T_min = 0.671, T_max = 0.848	R_int = 0.036
3530 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.029	0 restraints
wR(F²) = 0.074	H-atom parameters not refined
S = 1.10	Δρ_max = 0.41 e Å⁻³
981 reflections	Δρ_min = −0.60 e Å⁻³
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

	x	y	z	U_iso*/U_eq
Cu1	0.5000	0.06463 (3)	0.2500	0.01055 (18)
O1	0.3461 (2)	0.04164 (13)	0.08928 (18)	0.0119 (4)
O2	0.2652 (2)	−0.07906 (13)	−0.05100 (19)	0.0137 (4)
N1	0.5000	0.2074 (2)	0.2500	0.0099 (7)
N2	0.5000	−0.0746 (2)	0.2500	0.0096 (7)
C1	0.3334 (3)	−0.04888 (19)	0.0526 (3)	0.0111 (6)
C2	0.4161 (3)	−0.1210 (2)	0.1514 (3)	0.0100 (6)
C3	0.4135 (3)	−0.2221 (2)	0.1484 (3)	0.0120 (6)
H3	0.3542	−0.2564	0.0789	0.014*
C4	0.5000	−0.2728 (3)	0.2500	0.0130 (8)
H4	0.5000	−0.3426	0.2500	0.016*
C5	0.5748 (3)	0.2583 (2)	0.3507 (3)	0.0124 (6)
H5	0.6286	0.2230	0.4218	0.015*
C6	0.5765 (4)	0.3594 (2)	0.3549 (3)	0.0154 (6)
H6	0.6290	0.3931	0.4281	0.018*
C7	0.5000	0.4112 (3)	0.2500	0.0159 (9)
H7	0.5000	0.4810	0.2500	0.019*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Cu1	0.0144 (3)	0.0059 (3)	0.0109 (3)	0.000	−0.00649 (18)	0.000
O1	0.0151 (10)	0.0074 (10)	0.0129 (10)	−0.0014 (8)	−0.0066 (8)	0.0000 (8)
O2	0.0173 (10)	0.0117 (11)	0.0118 (10)	−0.0026 (8)	−0.0068 (8)	−0.0017 (8)
N1	0.0095 (16)	0.0095 (17)	0.0108 (17)	0.000	−0.0009 (13)	0.000
N2	0.0085 (16)	0.0102 (17)	0.0100 (16)	0.000	−0.0009 (13)	0.000
C1	0.0114 (14)	0.0106 (14)	0.0114 (15)	−0.0017 (11)	−0.0007 (11)	0.0004 (11)
C2	0.0080 (13)	0.0125 (15)	0.0095 (14)	−0.0020 (11)	−0.0011 (11)	−0.0023 (11)
C3	0.0122 (14)	0.0131 (15)	0.0108 (14)	−0.0006 (11)	−0.0019 (11)	−0.0018 (11)
C4	0.014 (2)	0.009 (2)	0.016 (2)	0.000	0.0001 (16)	0.000
C5	0.0124 (14)	0.0138 (15)	0.0110 (15)	0.0001 (11)	−0.0012 (11)	0.0007 (11)
C6	0.0163 (15)	0.0136 (15)	0.0163 (16)	−0.0035 (12)	0.0025 (12)	−0.0042 (12)
C7	0.016 (2)	0.009 (2)	0.023 (2)	0.000	0.0055 (17)	0.000

Geometric parameters (Å, º) top

Cu1—N2	1.896 (3)	C2—C3	1.378 (4)
Cu1—N1	1.944 (3)	C3—C4	1.392 (3)
Cu1—O1	2.0110 (18)	C3—H3	0.9500
Cu1—O1ⁱ	2.0110 (18)	C4—C3ⁱ	1.392 (3)
O1—C1	1.290 (3)	C4—H4	0.9500
O2—C1	1.228 (3)	C5—C6	1.378 (4)
N1—C5ⁱ	1.347 (3)	C5—H5	0.9500
N1—C5	1.347 (3)	C6—C7	1.390 (3)
N2—C2	1.332 (3)	C6—H6	0.9500
N2—C2ⁱ	1.332 (3)	C7—C6ⁱ	1.390 (3)
C1—C2	1.527 (4)	C7—H7	0.9500

N2—Cu1—N1	180.0	N2—C2—C1	111.7 (2)
N2—Cu1—O1	81.05 (5)	C3—C2—C1	128.5 (2)
N1—Cu1—O1	98.95 (5)	C2—C3—C4	118.2 (3)
N2—Cu1—O1ⁱ	81.05 (5)	C2—C3—H3	120.9
N1—Cu1—O1ⁱ	98.95 (5)	C4—C3—H3	120.9
O1—Cu1—O1ⁱ	162.10 (10)	C3—C4—C3ⁱ	120.6 (4)
C1—O1—Cu1	114.71 (16)	C3—C4—H4	119.7
C5ⁱ—N1—C5	118.1 (3)	C3ⁱ—C4—H4	119.7
C5ⁱ—N1—Cu1	120.97 (16)	N1—C5—C6	122.8 (3)
C5—N1—Cu1	120.96 (16)	N1—C5—H5	118.6
C2—N2—C2ⁱ	123.4 (3)	C6—C5—H5	118.6
C2—N2—Cu1	118.28 (16)	C5—C6—C7	118.7 (3)
C2ⁱ—N2—Cu1	118.28 (16)	C5—C6—H6	120.7
O2—C1—O1	126.2 (2)	C7—C6—H6	120.7
O2—C1—C2	120.2 (2)	C6ⁱ—C7—C6	119.0 (4)
O1—C1—C2	113.6 (2)	C6ⁱ—C7—H7	120.5
N2—C2—C3	119.8 (3)	C6—C7—H7	120.5

N2—Cu1—O1—C1	−6.98 (18)	Cu1—N2—C2—C3	−179.96 (18)
N1—Cu1—O1—C1	173.02 (18)	C2ⁱ—N2—C2—C1	−179.7 (2)
O1ⁱ—Cu1—O1—C1	−6.98 (18)	Cu1—N2—C2—C1	0.3 (2)
O1—Cu1—N1—C5ⁱ	−6.84 (14)	O2—C1—C2—N2	172.9 (2)
O1ⁱ—Cu1—N1—C5ⁱ	173.16 (14)	O1—C1—C2—N2	−6.2 (3)
O1—Cu1—N1—C5	173.16 (14)	O2—C1—C2—C3	−6.8 (4)
O1ⁱ—Cu1—N1—C5	−6.84 (14)	O1—C1—C2—C3	174.1 (3)
O1—Cu1—N2—C2	3.29 (14)	N2—C2—C3—C4	−0.1 (4)
O1ⁱ—Cu1—N2—C2	−176.71 (14)	C1—C2—C3—C4	179.6 (2)
O1—Cu1—N2—C2ⁱ	−176.71 (14)	C2—C3—C4—C3ⁱ	0.03 (18)
O1ⁱ—Cu1—N2—C2ⁱ	3.29 (14)	C5ⁱ—N1—C5—C6	0.47 (19)
Cu1—O1—C1—O2	−170.2 (2)	Cu1—N1—C5—C6	−179.53 (19)
Cu1—O1—C1—C2	8.8 (3)	N1—C5—C6—C7	−0.9 (4)
C2ⁱ—N2—C2—C3	0.04 (18)	C5—C6—C7—C6ⁱ	0.44 (18)

Symmetry code: (i) −x+1, y, −z+1/2.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	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+1/2; (ii) −x+1/2, −y−1/2, −z; (iii) x+1/2, −y+1/2, z+1/2.

Experimental details

Crystal data
Chemical formula	[Cu(C₇H₃NO₄)(C₅H₅N)]
M_r	307.74
Crystal system, space group	Monoclinic, C2/c
Temperature (K)	100
a, b, c (Å)	7.8042 (9), 13.6152 (17), 10.0667 (12)
β (°)	91.687 (4)
V (Å³)	1069.2 (2)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	2.06
Crystal size (mm)	0.21 × 0.13 × 0.08

Data collection
Diffractometer	Bruker APEXII CCD area-detector diffractometer
Absorption correction	Multi-scan (SADABS; Bruker, 2007)
T_min, T_max	0.671, 0.848
No. of measured, independent and observed [I > 2σ(I)] reflections	3530, 981, 859
R_int	0.036
(sin θ/λ)_max (Å⁻¹)	0.602

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.029, 0.074, 1.10
No. of reflections	981
No. of parameters	89
H-atom treatment	H-atom parameters not refined
Δρ_max, Δρ_min (e Å⁻³)	0.41, −0.60

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

Selected bond lengths (Å) top

Cu1—N2	1.896 (3)	Cu1—O1	2.0110 (18)
Cu1—N1	1.944 (3)	Cu1—O1ⁱ	2.0110 (18)

Symmetry code: (i) −x+1, y, −z+1/2.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	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+1/2; (ii) −x+1/2, −y−1/2, −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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