[μ-1,2-Bis(4-pyrid­yl)ethene-κ2 N:N′]bis­[aqua­(pyridine-2,6-dicarboxyl­ato-κ3 O 2,N,O 6)copper(II)] dihydrate

Shie Fu Lush

doi:10.1107/S1600536811018411

. 2011 May 20;67(Pt 6):m775. doi: 10.1107/S1600536811018411

[μ-1,2-Bis(4-pyridyl)ethene-κ² N:N′]bis[aqua(pyridine-2,6-dicarboxylato-κ³ O ²,N,O ⁶)copper(II)] dihydrate

Shie Fu Lush ^a,^*

PMCID: PMC3120317 PMID: 21754658

Abstract

In the title dinuclear Cu^II complex, [Cu₂(C₇H₃NO₄)₂(C₁₂H₁₀N₂)(H₂O)₂]·2H₂O, the water-coordinated Cu^II cation is O,N,O′-chelated by a pyridine-2,6-dicarboxylate (pdc) dianion, and one pyridine N atom from a 1,2-bis(4-pyridyl)ethene ligand coordinates to the Cu^II cation, completing the CuN₂O₃ distorted square-pyriamidial geometry. The Cu—O_water bond [2.388 (4) Å] in the axial direction is much longer than the other Cu—O bonds. The 1,2-bis(4-pyridyl)ethene ligand is located across an inversion center with the mid-point of the C=C bond at the inversion center, and bridges two Cu^II cations, generating a centrosymmetric dinuclear complex. The crystal structure is stabilized by classical O—H⋯O and weak C—H⋯O hydrogen bonds.

Related literature

For related Cu^II complexes with pyridine-2,6-dicarboxylate ligands, see: Chaigneau et al. (2004 ▶); Dong et al. (2010 ▶); Ghosh et al. (2004 ▶).

Experimental

Crystal data

[Cu₂(C₇H₃NO₄)₂(C₁₂H₁₀N₂)(H₂O)₂]·2H₂O
M _r = 711.59
Triclinic,
a = 5.2616 (5) Å
b = 7.9316 (7) Å
c = 16.8063 (14) Å
α = 89.183 (2)°
β = 84.541 (2)°
γ = 72.557 (2)°
V = 666.01 (10) Å³
Z = 1
Mo Kα radiation
μ = 1.67 mm⁻¹
T = 295 K
0.25 × 0.10 × 0.10 mm

Data collection

Bruker SMART 1000 CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2001 ▶) T _min = 0.921, T _max = 0.976
5755 measured reflections
2373 independent reflections
2174 reflections with I > 2σ(I)
R _int = 0.036

Refinement

R[F ² > 2σ(F ²)] = 0.054
wR(F ²) = 0.126
S = 1.23
2373 reflections
200 parameters
H-atom parameters constrained
Δρ_max = 0.57 e Å⁻³
Δρ_min = −0.60 e Å⁻³

Data collection: SMART (Bruker, 2007 ▶); cell refinement: SAINT (Bruker, 2007 ▶); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXTL; molecular graphics: PLATON (Spek, 2009 ▶); software used to prepare material for publication: PLATON.

Supplementary Material

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536811018411/xu5212sup1.cif

e-67-0m775-sup1.cif^{(18.6KB, cif)}

Structure factors: contains datablocks I. DOI: 10.1107/S1600536811018411/xu5212Isup2.hkl

e-67-0m775-Isup2.hkl^{(116.6KB, hkl)}

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

Table 1. Selected bond lengths (Å).

Cu1—O1	2.388 (4)
Cu1—O2	2.053 (3)
Cu1—O4	2.003 (4)
Cu1—N1	1.902 (3)
Cu1—N2	1.951 (4)

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Table 2. Hydrogen-bond geometry (Å, °).

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O1—H1A⋯O6	0.82	2.10	2.669 (8)	126
O1—H1B⋯O2ⁱ	0.82	1.99	2.809 (5)	175
O6—H6A⋯O3ⁱ	0.82	2.31	2.919 (9)	132
O6—H6B⋯O3ⁱⁱ	0.82	2.06	2.851 (8)	163
C2—H2A⋯O1ⁱⁱⁱ	0.93	2.54	3.348 (6)	146
C4—H4A⋯O3^iv	0.93	2.52	3.411 (6)	160
C8—H8A⋯O1^v	0.93	2.49	3.381 (6)	161
C9—H9A⋯O5^vi	0.93	2.47	3.382 (6)	167
C13—H13A⋯O5^vii	0.93	2.35	3.265 (6)	166

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Symmetry codes: (i) Inline graphic ; (ii) ; (iii) ; (iv) ; (v) ; (vi) ; (vii) .

Acknowledgments

This work was supported financially by Yuanpei University, Taiwan.

supplementary crystallographic information

Comment

The pyridine-2,6-dicarboxylic acid (pdcH₂) has important coordination functions to transition metals by either carboxylate bridges between metal centers, to form dimeric complexes or tridentate (O, N, O') chelation to one metal ion. Some Cu^II pdc complexes have been reported (Chaigneau et al., 2004; Ghosh et al., 2004; Dong et al., 2010).

In the title compound, [Cu₂(C₁₂H₁₀N₂)(C₇H₃NO₄)₂(H₂O)₂].2(H₂O)], the Cu^II atom is coordinated by two oxygen atoms and one nitrogen atom of one pyridine-2,6-dicarboxylate (pdc) ligand, one pyrinyl N atom of the 1,2-bis(4-pyridyl)ethene ligand. The distorted square-pyriamidial geometry is completed by a longer axial bond to the O atom of a water molecule [Cu—O 2.390 (43) Å in the axial direction]. The Cu1—N2—N2ⁱ—Cu1ⁱ torsion angle is 180.0 (13)°, assemblies exhibiting M—anti-1,2-bis(4-pyridyl)ethene—M bridges. Two Cu^II atoms are bridged by one trans-1,2-bis(4-pyridyl)ethene ligand, generating a dinuclear molecule.The dinuclear molecule is located on a centre of inversion, which is in the middle of the ethylyne fragment of the bpe ligand.

The molecular structure and packing are stabilized by strong O—H···O and weak C—H···O hydrogen bonds, also including a crystal water molecule.

Experimental

A solution of Cu(NO₃)₂.6H₂O (0.296 g, 1 mmol) in 5 ml H₂O was added to pyridine-2,6-dicarboxylic acid (0.167, 1 mmol) and 1,2-bis(4-pyridyl)ethane (0.184 g, 1 mmol) in a Teflon-lined stainless steel autoclave which was heated under autogenous pressure to 453 K for 72 h and then allowed to cool to room temperature. Blue columnar crystals of the title compound were collected in 42.35% yield (based on Cu).