Bis[1-meth­oxy-2,2,2-tris­(pyrazol-1-yl-κN 2)ethane]­nickel(II) bis­(tri­fluoro­methane­sulfonate) dihydrate

Ganna Lyubartseva; Sean Parkin; Uma Prasad Mallik

doi:10.1107/S1600536813024252

. 2013 Sep 4;69(Pt 10):m532–m533. doi: 10.1107/S1600536813024252

Bis[1-methoxy-2,2,2-tris(pyrazol-1-yl-κN ²)ethane]nickel(II) bis(trifluoromethanesulfonate) dihydrate

Ganna Lyubartseva ^a,^*, Sean Parkin ^b, Uma Prasad Mallik ^a

PMCID: PMC3790345 PMID: 24098167

Abstract

In the title salt, [Ni(C₁₂H₁₄N₆O)₂](CF₃SO₃)₂·2H₂O, the Ni^II cation is located on an inversion centre and is coordinated by six N atoms from two tridentate 1-methoxy-2,2,2-tris(pyrazol-1-yl)ethane ligands in a distorted octahedral geometry. The Ni—N distances range from 2.0594 (12) to 2.0664 (12) Å, intra-ligand N—Ni—N angles range from 84.59 (5) to 86.06 (5)°, and adjacent inter-ligand N—Ni—N angles range between 93.94 (5) and 95.41 (5)°. In the crystal, inversion-related pyrazole rings are π–π stacked, with an interplanar spacing of 3.4494 (18) Å, forming chains that propagate parallel to the a-axis direction. Intermolecular O—H⋯O hydrogen bonds are present between water molecules and trifluoromethanesulfonate anions.

Related literature

Pyrazole-based tridentate ligands are drawing more attention because of their topology and nature of donor atoms, see: Paulo et al. (2004 ▶); Bigmore et al. (2005 ▶). For the ligand synthesis, see: Maria et al. (2007 ▶). The compound reported here was prepared as part of our ongoing research effort to study nitrogen-donor tridentate scorpionate ligands coordinated to nickel, see: Lyubartseva et al. (2011 ▶, 2012 ▶); Lyubartseva & Parkin (2009 ▶).

Experimental

Crystal data

[Ni(C₁₂H₁₄N₆O)₂](CF₃O₃S)₂·2H₂O
M _r = 909.46
Triclinic,
a = 8.5582 (2) Å
b = 9.6515 (2) Å
c = 12.2347 (2) Å
α = 110.399 (1)°
β = 103.665 (1)°
γ = 97.317 (1)°
V = 895.66 (3) Å³
Z = 1
Mo Kα radiation
μ = 0.76 mm⁻¹
T = 90 K
0.26 × 0.22 × 0.15 mm

Data collection

Nonius KappaCCD diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 2008a ▶) T _min = 0.760, T _max = 0.862
25573 measured reflections
4095 independent reflections
3708 reflections with I > 2σ(I)
R _int = 0.023

Refinement

R[F ² > 2σ(F ²)] = 0.029
wR(F ²) = 0.072
S = 1.07
4095 reflections
266 parameters
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.47 e Å⁻³
Δρ_min = −0.49 e Å⁻³

Data collection: COLLECT (Nonius, 1998 ▶); cell refinement: SCALEPACK (Otwinowski & Minor, 1997 ▶); data reduction: DENZO-SMN (Otwinowski & Minor, 1997 ▶); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008b ▶); program(s) used to refine structure: SHELXL2013 (Sheldrick, 2008b ▶); molecular graphics: XP in SHELXTL (Sheldrick, 2008b ▶); software used to prepare material for publication: SHELXL2013.

Supplementary Material

Crystal structure: contains datablock(s) global, I. DOI: 10.1107/S1600536813024252/tk5252sup1.cif

e-69-0m532-sup1.cif^{(751.8KB, cif)}

Structure factors: contains datablock(s) I. DOI: 10.1107/S1600536813024252/tk5252Isup2.hkl

e-69-0m532-Isup2.hkl^{(224.6KB, hkl)}

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

Table 1. Hydrogen-bond geometry (Å, °).

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O1W—H2W⋯O3A	0.94 (3)	2.06 (3)	2.994 (2)	174 (2)
O1W—H1W⋯O3A ⁱ	0.97 (3)	2.12 (3)	3.0613 (19)	163 (2)

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Symmetry code: (i) Inline graphic .

Acknowledgments

GL gratefully acknowledges the Southern Arkansas University Faculty Research Grant for financial support.

supplementary crystallographic information

1. Comment

The described structure was studied in continuation of on-going studies (Lyubartseva & Parkin, 2009; Lyubartseva et al., 2011, 2012) owing to interest in pyrazole-based tridentate ligands (Paulo et al., 2004; Bigmore et al., 2005). In an attempt to prepare mononuclear [LNi^II(CN)₃]^-, where L is 1-methoxy-2,2,2-tris(pyrazol-1-yl)ethane, a tridentate neutral nitrogen donor ligand, we isolated the major product [Ni(C₁₂H₁₄N₆0₂)₂][CF₃SO₃]₂·2H₂O as light-pink triclinic crystals. In the crystal, the Ni(II) cation is situated on an inversion centre and is coordinated by six N atoms from the two tridentate tpmOMe ligands, Fig. 1, (average Ni—N distance = 2.062 Å) in a distorted octahedral geometry. The average N—Ni—N angle between adjacent pyrazole-ring coordinated N atoms is 85.13° for the six acute angles and 94.87° for the six obtuse angles. In the crystal, inversion-related (-x, 1 - y, 1 - z) pyrazole rings are π—π stacked, with an interplanar spacing of 3.4494 (18) Å, forming chains that propagate parallel to the a axis. Intramolecular O—H···O hydrogen bonds are present between water and trifluoromethanesulfonate anion, Table 1.

2. Experimental

1-Methoxy-2,2,2-tris(pyrazol-1-yl)ethane ligand was synthesized according to the previously published procedure of Maria et al. (2007). Nickel trifluoromethanesulfonate was used as received. Ni(OTf)₂ (358 mg, 1 mmol), 1-methoxy-2,2,2-tris(pyrazol-1-yl)ethane (258 mg, 1 mmol) and NEt₄CN (312 mg, 2 mmol) were suspended in a mixture of methanol (20 ml) and water (10 ml), and stirred for 30 minutes. The resulting solution was filtered and solvent was slowly evaporated in air. Light-pink crystals were obtained after 3 weeks (294 mg, 64.6% yield). Elemental analysis, calculated for C₂₆H₃₂F₆N₁₂NiO₁₀S₂: C 34.34, H 3.55, N 18.48; found C 34.64, H 3.40, N 18.35. IR (cm^-1): 3624, 3487, 3145, 2920, 1615, 1523, 1410, 1388, 1340, 1323, 1257, 1225, 1199, 1164, 1105, 1069, 1059, 1028, 1010, 973, 919, 854, 755, 674, 653, 635, 602, 572, 516.