Tetra­aqua­bis(3,5-di-4-pyridyl-1,2,4-triazolato-κN)cobalt(II) dihydrate

Lin Yi Dong

doi:10.1107/S1600536809011982

. 2009 Apr 8;65(Pt 5):m487–m488. doi: 10.1107/S1600536809011982

Tetraaquabis(3,5-di-4-pyridyl-1,2,4-triazolato-κN)cobalt(II) dihydrate

Lin Yi Dong ^a,^*

PMCID: PMC2977553 PMID: 21583739

Abstract

The Co^II atom in the title compound, [Co(C₁₂H₈N₅)₂(H₂O)₄]·2H₂O, lies on a center of inversion and is bonded to two N-heterocycles and to four water molecules in a slightly distorted octahedral coordination. The coordinated and lattice water molecules interact with the N-heterocycles through O—H⋯N hydrogen bonds, generating a three-dimensional supramolecular architecture.

Related literature

For magnetic studies of transition metal complexes with 1,2,4-triazole derivatives, see: Haasnoot (2000 ▶). For the potential applications of complexes containing substituted 1,2,4-triazole ligands with spin-crossover properties in molecular-based memory devices, displays and optical switches, see: Kahn & Martinez (1998 ▶). For 3,5-di(4-pyridine)-1,2,4-triazole, see: Zhang et al. (2006 ▶); Sreenivasulu & Vittal (2004 ▶). For the structure of water, see: Tajkhorshid et al. (2002 ▶). For the synthesis, see: Basu & Dutta (1964 ▶). For a trinuclear water cluster, see: König (1944 ▶).

Experimental

Crystal data

[Co(C₁₂H₈N₅)₂(H₂O)₄]·2H₂O
M _r = 611.49
Monoclinic,
a = 7.3660 (15) Å
b = 15.654 (3) Å
c = 11.857 (2) Å
β = 107.34 (3)°
V = 1305.1 (5) Å³
Z = 2
Mo Kα radiation
μ = 0.72 mm⁻¹
T = 293 K
0.40 × 0.20 × 0.12 mm

Data collection

Bruker SMART CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 1996 ▶) T _min = 0.842, T _max = 0.917
11054 measured reflections
2423 independent reflections
2009 reflections with I > 2σ(I)
R _int = 0.065

Refinement

R[F ² > 2σ(F ²)] = 0.054
wR(F ²) = 0.108
S = 1.07
2420 reflections
243 parameters
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.29 e Å⁻³
Δρ_min = −0.41 e Å⁻³

Data collection: SMART (Bruker, 1997 ▶); cell refinement: SAINT (Bruker, 1997 ▶); data reduction: SAINT; program(s) used to solve structure: SHELXL97 (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: DIAMOND (Brandenburg, 1999 ▶); software used to prepare material for publication: publCIF (Westrip, 2009 ▶).

Supplementary Material

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536809011982/ng2566sup1.cif

e-65-0m487-sup1.cif^{(18.9KB, cif)}

Structure factors: contains datablocks I. DOI: 10.1107/S1600536809011982/ng2566Isup2.hkl

e-65-0m487-Isup2.hkl^{(118.9KB, hkl)}

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

Table 1. Selected geometric parameters (Å, °).

Co1—O1	2.100 (2)
Co1—O2	2.126 (2)
Co1—N1	2.134 (3)

Open in a new tab

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

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O1—H1A⋯N3ⁱⁱ	0.851 (10)	2.42 (3)	3.070 (4)	134 (3)
O1—H1A⋯N4ⁱⁱ	0.851 (10)	1.966 (12)	2.803 (4)	167 (4)
O1—H1B⋯O3ⁱⁱⁱ	0.852 (10)	1.99 (2)	2.791 (4)	155 (3)
O2—H2A⋯O3	0.851 (10)	1.973 (14)	2.801 (4)	164 (3)
O2—H2B⋯N3^iv	0.850 (10)	1.973 (19)	2.792 (4)	161 (5)
O2—H2B⋯N4^iv	0.850 (10)	2.60 (4)	3.220 (4)	130 (4)
O3—H3A⋯N2^v	0.852 (10)	2.077 (12)	2.926 (4)	174 (4)
O3—H3B⋯N5^vi	0.849 (10)	1.950 (14)	2.786 (4)	168 (5)

Open in a new tab

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

supplementary crystallographic information

Comment

Transition metal complexes with 1,2,4-triazole derivatives as ligands are of great interest as they are the subject of magnetic studies (Haasnoot, 2000). Some complexes containing substituted 1,2,4-triazole ligands have spin-crossover properties, which could be used in molecular-based memory devices, displays and optical switches (Kahn & Martinez, 1998). The ligand 3,5-di(4-pyridine)-1,2,4-triazole (L) is of special interest as it contains multi-dentate donor atoms and shows diverse coordination modes.. Especially only a few examples about the coordinaiton chemistry of L are reported. Some unusual coordination modes of L also have been reported forming interesting supramolecular isomerism systems (Zhang et al., 2006). On the other hand, water is quite important for our common life (Tajkhorshid et al., 2002). It has been the focus of intense research interests for their unusual properties in biological system and also plays an important role in biological self-assembly processes (Sreenivasulu & Vittal, 2004).

In this work, we synthesized a new compound [Co(L)₂(H₂O)₄](H₂O)₂ (I) (L = 3,5-di(4-pyridine)-1,2,4-triazole). 1 is composed of one cobalt(II) cation, two L ligand, four coordinated and two lattice water molecules. The cobalt(II) cation is six-coordinated in the octahedral geometry. The equatorial site of Cobalt cation is occupied by four aqua molecules while the axial site is occupied by two nitrogen atoms of two mono-dentate L ligands. The mono-dentate coordination mode of L is different from previously reported di-, tri- or tetra-dentate coordination modes of L.

O1, O2 from coordination water molecules and O3 from lattice water molecules generate strong intermolecular hydrogen bondings and construct trinuclear water clusters, in which O3 acts as the hydrogen acceptors and O1, O2 act as hydrogen bonding donors. The hydrogen-bonding distances are 2.791 (4) Å (O1—H1B···O3) and 2.801 (4) Å(O2—H2A···O3), respectively. The average O···O distance is 2.796 (4) Å, which is similar to that(2.75 Å) in the structure of ice (König, 1944).

strong N—H···O hydrogen bonds generated from water molecules and nitrogen atoms of pyridine or triazole groups are also observed rusulting in the three-dimensional supramolecular network(Table 2). π-π stacking interactions between two neighboring triazole groups further consolidating the architecture centroid-centroid distance 3.677 (4) Å]

Perspective drawing with the atomic numbering scheme is illustrated in figure 1. Selected geometric parameters (Å, °) for 1 are listed in table 1. Selected hydrogen-bonding geometric parameters (Å, °) for 1 are listed in table 2. The trinuclear water clusters, corresponding N—H···O hydrogen bonds and π-π stacking are shown in figure 2. The three-dimensional supramolecular packing architecture of (I) is shown in figure 3.

Experimental

The ligand was prepared according to the previous literature (Basu & Dutta, (1964)). [Co(L)₂(H₂O)₄](H₂O) (1) (L = 3,5-di(4-pyridine)-1,2,4-triazole) was prepared under the hydrotheraml conditions. [Co(ClO₄)₂].6H₂O (0.2 mmol), L (0.2 mmol) and 18 ml water was added to a 25 ml reaction vessel. the reaction vessel was then sealed and subsequently placed in an oven for 140 h at 160°C. well shaped red block crystals were obtained and washed with ethanol.