[μ-2,3,5,6-Tetra­kis(2-pyrid­yl)pyrazine-κ6N6,N1,N2:N3,N4,N5]bis­[diaqua(dihydrogen m-phenylene­diphospho­nato-κO)nickel(II)] dihydrate

DeBurgomaster, P.; Zubieta, J.

doi:10.1107/S1600536810041279

metal-organic compounds

CRYSTALLOGRAPHIC
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ISSN: 2056-9890

Volume 66| Part 11| November 2010| Pages m1424-m1425

https://doi.org/10.1107/S1600536810041279

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[μ-2,3,5,6-Tetrakis(2-pyridyl)pyrazine-κ⁶N⁶,N¹,N²:N³,N⁴,N⁵]bis[diaqua(dihydrogen m-phenylenediphosphonato-κO)nickel(II)] dihydrate

Paul DeBurgomaster ^a and Jon Zubieta ^a ^*

^aDepartment of Chemistry, Syracuse University, Syracuse, New York 13244, USA
^*Correspondence e-mail: jazubiet@syr.edu

(Received 27 September 2010; accepted 13 October 2010; online 23 October 2010)

The title compound [Ni₂(C₆H₆O₆P₂)₂(C₂₄H₁₆N₆)(H₂O)₄]·2H₂O or [Ni₂(tpyprz)(1,3-HO₃PC₆H₄PO₃H)₂(H₂O)₄]·2H₂O [tpyprz = tetrakis(2-pyridyl)pyrazine, C₂₄H₁₆N₆] is a binuclear complex with a crystallographic inversion center located at the center of the pyrazine ring. The equivalent nickel(II) sites exhibit a distorted {NiO₃N₃} octahedral coordination, with the three nitrogen donors of each terminus of the tpyprz ligand in a meridional orientation. An aqua ligand occupies the position trans to the pyrazine nitrogen donor, while the second aqua ligand is trans to the oxygen donor of the dihydrogen-1,3-phenyldiphosphonate ligand. The Ni—O and Ni—N bond lengths fall in the range 2.011 (3) to 2.089 (3) Å. The protonation sites on the organophosphonate ligand are evident in the significantly longer P—O bonds compared to the unprotonated sites. In the crystal structure, the complex molecules and the solvent water molecules are linked into a three-dimensional hydrogen-bonded framework through O—H⋯O interactions between the aqua ligands, the protonated organophosphonate oxygen atoms and the water molecules of crystallization. Intramolecular π-stacking between the phenyl group of the phosphonate ligand and a pyridyl group of the tpyprz ligand, at a distance of 3.244 (5) Å between ring centroids, is also observed.

Related literature

For general background to metal-organophosphonates, see: Alberti et al. (1978 ); Clearfield (1998 ); Finn et al. (2003 ); Vermeulen (1997 ). For nickel–organophosphonates, see: Bauer et al. (2008 ). For nickel–tetrakis(2-pyridyl)pyrazine complexes, see: Burkholder et al. (2003 ); Burkholder & Zubieta (2004 , 2005 ). For the use of tetrakis(2-pyridyl)pyrazine as a component in the construction of metal–organophosphonate materials, see: Armatas et al. (2008 ).

Experimental

Crystal data

[Ni₂(C₆H₆O₆P₂)₂(C₂₄H₁₆N₆)(H₂O)₄]·2H₂O
M_r = 1086.04
Triclinic, $[P \overline 1]$
a = 7.9702 (6) Å
b = 10.0785 (8) Å
c = 14.0960 (12) Å
α = 85.386 (2)°
β = 81.707 (1)°
γ = 69.364 (1)°
V = 1048.03 (15) Å³
Z = 1
Mo Kα radiation
μ = 1.14 mm⁻¹
T = 298 K
0.20 × 0.14 × 0.11 mm

Data collection

Bruker APEX CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 1998 ) T_min = 0.804, T_max = 0.885
10484 measured reflections
5044 independent reflections
4821 reflections with I > 2σ(I)
R_int = 0.023

Refinement

R[F² > 2σ(F²)] = 0.066
wR(F²) = 0.133
S = 1.32
5044 reflections
304 parameters
H-atom parameters constrained
Δρ_max = 0.91 e Å⁻³
Δρ_min = −0.80 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O2—H2′⋯O3ⁱ	0.82	1.91	2.536 (4)	132
O5—H5′⋯O6ⁱⁱ	0.82	1.82	2.606 (4)	162
O40—H40A⋯O3ⁱⁱⁱ	0.84	1.95	2.784 (4)	170
O40—H40B⋯O4^iv	0.88	1.83	2.711 (4)	175
O41—H41B⋯O6^iv	0.83	1.82	2.625 (4)	163
O90—H90B⋯O4^v	0.92	1.84	2.747 (4)	166
O41—H41A⋯O90	0.88	1.83	2.643 (4)	151
O90—H90A⋯O1	0.92	1.92	2.780 (4)	154
Symmetry codes: (i) -x+1, -y+1, -z+1; (ii) -x+1, -y, -z+2; (iii) x-1, y, z; (iv) x-1, y+1, z; (v) x, y+1, z.

Data collection: SMART (Bruker, 1998); cell refinement: SAINT (Bruker, 1998); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: DIAMOND (Brandenburg & Putz, 1999 ); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Supporting information

Crystal structure: contains datablocks I, New_Global_Publ_Block. DOI: https://doi.org/10.1107/S1600536810041279/pk2273sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536810041279/pk2273Isup2.hkl

checkCIF report

Comment top

The chemistry of metal-organophosphonates has witnessed dramatic growth (Clearfield, 1998; Finn et al., 2003; Vermeulen, 1997) since the first reports in the 1970s of the layered metal-organophosphonates (Alberti et al., 1978). In our investigations of metal oxide materials, we have used organodiphosphonates as tethers between metal or metal oxide nodes (Armatas et al., 2008). Structural expansion and diversity could be accomplished by introducing additional components, most commonly a M(II)-organonitrogen ligand complex. A particularly useful nitrogen donor ligand for structural manipulation is the dipodal tetrakis(2-pyridyl)pyrazine (tpyprz) (Armatas et al., 2008; Bauer et al., 2008). While Cu(II) has generally served as the secondary metal in the M(II)-organonitrogen ligand complex, Ni(II)-containing subunits have also been exploited as subunits (Burkholder et al., 2003; Burkholder and Zubieta, 2004; Burkholder and Zubieta, 2005). While the secondary metal M(II) bonds to the tpyprz ligand and aqua ligands and/or cluster oxide groups in such materials, the title complex was prepared in the absence of metal oxide, affording the binuclear [Ni₂(tpyprz)(1,3-HO₃PC₆H₄PO₃H) (H₂O)₄]dihydrate.

As shown in Fig. 1, the structure of the title compound is binuclear, with a crystallographic inversion center at the mid-point of the pyrazine group. The distorted {NiO₃N₃} octahedral geometry at the Ni(II) site is defined by the nitrogen donors of the tpyprz ligand in a meridional orientation, two aqua ligands and an oxygen donor from the pendant monodentate 1,3-phenyldiphosphonate ligand. One aqua ligand is trans to the pyrazine nitrogen donor of the tpyprz ligand, while the second occupies a position trans to the phosphonate oxygen donor. The shortest Ni—N distance is to the pyrazine nitrogen, Ni—N2 of 2.011 (3) Å, while the Ni-pyridyl bond distances are 2.076 (3) Å and 2.089 (3) Å. The Ni—O(aqua) distances are 2.015 (3) Å and 2.081 (3) Å, while the Ni—O(phosphonate) distance is 2.082 (3) Å.

Charge compensation considerations require that the phenyldiphosphonate ligand be in the doubly deprotonated state [H₂(O₃PC₆H₄PO₃)]^2-. The protonation sites were revealed in the difference Fourier map by peaks adjacent to O2 and O5 at distances consistent with bound hydrogen. The P—O bond lengths support these protonation sites with P—O2 and P—O5 of 1.567 (3) Å and 1.574 (3) Å, respectively, compared to an average P—O distance of 1.515 (4)Å for the remaining P—O distances.

The structure is stabilized by intermolecular hydrogen bonding between the aqua ligands, the P—OH groups and the waters of crystallization. The binuclear complexes and the water of crystallization are linked into a three-dimensional framework through this hydrogen bonding (Fig. 2). There is also intramolecular π-stacking between the phosphonate phenyl ring and a pyridyl group of the tpyprz ligand with a distance of 3.244 (5)Å between centroids. Intermolecular π-stacking between the phosphonate phenyl group and a pyridyl ring of a tpyprz ligand of an adjacent molecule exhibits a distance of 3.584 (5)Å between centroids.

Related literature top

For general background to metal-organophosphonates, see: Alberti et al. (1978); Clearfield (1998); Finn et al. (2003); Vermeulen (1997). For nickel–organophosphonates, see: Bauer et al. (2008). For nickel–tetrakis(2-pyridyl)pyrazine complexes, see: Burkholder et al. (2003); Burkholder & Zubieta (2004); Burkholder & Zubieta (2005). For the use of tetrakis(2-pyridyl)pyrazine as a component in the construction of metal–organophosphonate materials, see: Armatas et al. (2008).

Experimental top

A solution of Ni(CH₃CO₂)₂•4H₂O (0.074 g, 0.297 mmol), tpyprz (0.085 g, 0.219 mmol) and 1,3-phenyldiphosphonic acid (0.071 g, 0.301 mmol) in water (10 ml) was placed in a Parr acid digestion bomb and heated to 170°C for 48 h. Yellow blocks of the compound suitable for x-ray diffraction studies were isolated in 65% yield. Anal Calcd. for C₃₆H₄₀N₆Ni₂O₁₈P₄: C, 39.8; H, 3.68; N. 7.73. Found: C, 39.6; H, 3.75; N, 7.65.

Structure description top

For general background to metal-organophosphonates, see: Alberti et al. (1978); Clearfield (1998); Finn et al. (2003); Vermeulen (1997). For nickel–organophosphonates, see: Bauer et al. (2008). For nickel–tetrakis(2-pyridyl)pyrazine complexes, see: Burkholder et al. (2003); Burkholder & Zubieta (2004); Burkholder & Zubieta (2005). For the use of tetrakis(2-pyridyl)pyrazine as a component in the construction of metal–organophosphonate materials, see: Armatas et al. (2008).

Computing details top

Data collection: SMART (Bruker, 1998); cell refinement: SAINT (Bruker, 1998); data reduction: SAINT (Bruker, 1998); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: DIAMOND (Brandenburg & Putz, 1999); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top

	Fig. 1. An ellipsoid plot of the structure of the binuclear complex [Ni₂(tpyprz)(HO₃PC₆H₄PO₃H)₂(H₂O)₄], showing the atom labeling scheme for the asymmetric unit and displacement ellipsoids at the 50% probability level for all non-H atoms. Hydrogen atms are shown as small arbitrary spheres. Color scheme: Ni, green; P, yellow; oxygen, red; nitrogen, blue; carbon, black.
	Fig. 2. Packing diagram in the bc plane. The hydrogen bonds are shown as rendered multi-band cylinders in red and gray.

[µ-2,3,5,6-Tetrakis(2-pyridyl)pyrazine- κ⁶N⁶,N¹,N²:N³,N⁴,N⁵] bis[diaqua(dihydrogen m-phenylenediphosphonato-κO)nickel(II)] dihydrate top

Crystal data top

[Ni₂(C₆H₆O₆P₂)₂(C₂₄H₁₆N₆)(H₂O)₄]·2H₂O	Z = 1
M_r = 1086.04	F(000) = 558
Triclinic, P1	D_x = 1.721 Mg m⁻³ D_m = 1.724 (2) Mg m⁻³ D_m measured by flotation
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 7.9702 (6) Å	Cell parameters from 3874 reflections
b = 10.0785 (8) Å	θ = 2.8–28.2°
c = 14.0960 (12) Å	µ = 1.14 mm⁻¹
α = 85.386 (2)°	T = 298 K
β = 81.707 (1)°	Block, yellow
γ = 69.364 (1)°	0.20 × 0.14 × 0.11 mm
V = 1048.03 (15) Å³

Data collection top

Bruker APEX CCD area-detector diffractometer	5044 independent reflections
Radiation source: fine-focus sealed tube	4821 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.023
φ and ω scans	θ_max = 28.1°, θ_min = 2.8°
Absorption correction: multi-scan (SADABS; Bruker, 1998)	h = −10→10
T_min = 0.804, T_max = 0.885	k = −13→13
10484 measured reflections	l = −18→18

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)] = 0.066	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.133	H-atom parameters constrained
S = 1.32	w = 1/[σ²(F_o²) + (0.0262P)² + 4.5072P] where P = (F_o² + 2F_c²)/3
5044 reflections	(Δ/σ)_max < 0.001
304 parameters	Δρ_max = 0.91 e Å⁻³
0 restraints	Δρ_min = −0.80 e Å⁻³

Crystal data top

[Ni₂(C₆H₆O₆P₂)₂(C₂₄H₁₆N₆)(H₂O)₄]·2H₂O	γ = 69.364 (1)°
M_r = 1086.04	V = 1048.03 (15) Å³
Triclinic, P1	Z = 1
a = 7.9702 (6) Å	Mo Kα radiation
b = 10.0785 (8) Å	µ = 1.14 mm⁻¹
c = 14.0960 (12) Å	T = 298 K
α = 85.386 (2)°	0.20 × 0.14 × 0.11 mm
β = 81.707 (1)°

Data collection top

Bruker APEX CCD area-detector diffractometer	5044 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 1998)	4821 reflections with I > 2σ(I)
T_min = 0.804, T_max = 0.885	R_int = 0.023
10484 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.066	0 restraints
wR(F²) = 0.133	H-atom parameters constrained
S = 1.32	Δρ_max = 0.91 e Å⁻³
5044 reflections	Δρ_min = −0.80 e Å⁻³
304 parameters

Special details top

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
Ni1	−0.07580 (6)	0.67510 (5)	0.69829 (3)	0.00726 (13)
P1	0.36680 (13)	0.53302 (10)	0.64046 (7)	0.00822 (19)
P2	0.44896 (13)	0.03282 (10)	0.85848 (7)	0.0097 (2)
O1	0.1916 (4)	0.6581 (3)	0.6542 (2)	0.0117 (5)
O2	0.3592 (4)	0.4229 (3)	0.5703 (2)	0.0121 (5)
H2'	0.3391	0.4617	0.5177	0.018*
O3	0.5296 (4)	0.5787 (3)	0.60760 (19)	0.0118 (5)
O4	0.4279 (4)	−0.0163 (3)	0.76433 (19)	0.0125 (5)
O5	0.2948 (4)	0.0145 (3)	0.9359 (2)	0.0151 (6)
H5'	0.3043	0.0409	0.9878	0.023*
O6	0.6315 (4)	−0.0397 (3)	0.8936 (2)	0.0131 (6)
O40	−0.3505 (4)	0.7120 (3)	0.7354 (2)	0.0135 (6)
H40A	−0.3999	0.6770	0.6998	0.020 (13)*
H40B	−0.4191	0.8019	0.7417	0.019 (13)*
O41	−0.0740 (4)	0.7601 (3)	0.82264 (19)	0.0125 (6)
H41A	0.0129	0.7965	0.8162	0.041 (17)*
H41B	−0.1766	0.8105	0.8461	0.036 (17)*
O90	0.1372 (4)	0.9039 (3)	0.7492 (2)	0.0190 (6)
H90A	0.1811	0.8321	0.7059	0.038 (17)*
H90B	0.2363	0.9222	0.7635	0.049 (19)*
N1	−0.0352 (4)	0.4705 (3)	0.7536 (2)	0.0101 (6)
N2	−0.0652 (4)	0.5726 (3)	0.5797 (2)	0.0089 (6)
N3	−0.1409 (4)	0.8436 (3)	0.5978 (2)	0.0107 (6)
C1	0.3907 (5)	0.4355 (4)	0.7530 (3)	0.0102 (7)
C2	0.4116 (5)	0.2912 (4)	0.7604 (3)	0.0114 (7)
H2	0.4237	0.2423	0.7052	0.014*
C3	0.4145 (5)	0.2200 (4)	0.8494 (3)	0.0102 (7)
C4	0.3956 (6)	0.2949 (4)	0.9323 (3)	0.0145 (8)
H4	0.3961	0.2488	0.9922	0.017*
C5	0.3764 (6)	0.4373 (4)	0.9252 (3)	0.0149 (8)
H5	0.3654	0.4861	0.9803	0.018*
C6	0.3734 (5)	0.5074 (4)	0.8364 (3)	0.0132 (8)
H6	0.3598	0.6031	0.8324	0.016*
C7	−0.0568 (5)	0.4352 (4)	0.8473 (3)	0.0138 (8)
H7A	−0.0539	0.4973	0.8919	0.017*
C8	−0.0831 (6)	0.3106 (4)	0.8799 (3)	0.0175 (8)
H8A	−0.0939	0.2877	0.9452	0.021*
C9	−0.0931 (6)	0.2202 (4)	0.8141 (3)	0.0177 (8)
H9	−0.1152	0.1371	0.8347	0.021*
C10	−0.0699 (5)	0.2546 (4)	0.7170 (3)	0.0137 (8)
H10	−0.0761	0.1950	0.6716	0.016*
C11	−0.0373 (5)	0.3793 (4)	0.6889 (3)	0.0113 (7)
C12	−0.0117 (5)	0.4313 (4)	0.5878 (3)	0.0080 (7)
C13	−0.0605 (5)	0.6454 (4)	0.4965 (3)	0.0087 (7)
C14	−0.1448 (5)	0.8029 (4)	0.5091 (3)	0.0100 (7)
C15	−0.2340 (5)	0.8978 (4)	0.4408 (3)	0.0124 (7)
H15	−0.2421	0.8667	0.3818	0.015*
C16	−0.3113 (5)	1.0407 (4)	0.4623 (3)	0.0134 (8)
H16	−0.3729	1.1066	0.4180	0.016*
C17	−0.2956 (5)	1.0839 (4)	0.5507 (3)	0.0146 (8)
H17	−0.3395	1.1796	0.5649	0.017*
C18	−0.2134 (5)	0.9818 (4)	0.6170 (3)	0.0132 (8)
H18	−0.2083	1.0101	0.6774	0.016*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Ni1	0.0073 (2)	0.0063 (2)	0.0088 (2)	−0.00260 (17)	−0.00161 (17)	−0.00129 (17)
P1	0.0087 (4)	0.0077 (4)	0.0083 (4)	−0.0029 (3)	−0.0011 (3)	−0.0003 (3)
P2	0.0117 (5)	0.0082 (4)	0.0089 (4)	−0.0027 (4)	−0.0022 (4)	0.0002 (3)
O1	0.0107 (13)	0.0096 (13)	0.0151 (13)	−0.0043 (10)	−0.0013 (10)	0.0003 (10)
O2	0.0142 (13)	0.0122 (13)	0.0115 (13)	−0.0064 (11)	−0.0020 (10)	−0.0004 (10)
O3	0.0134 (13)	0.0162 (14)	0.0085 (12)	−0.0082 (11)	−0.0019 (10)	−0.0014 (10)
O4	0.0164 (14)	0.0101 (13)	0.0112 (13)	−0.0041 (11)	−0.0022 (11)	−0.0032 (10)
O5	0.0158 (14)	0.0177 (14)	0.0125 (14)	−0.0071 (12)	−0.0009 (11)	−0.0006 (11)
O6	0.0126 (13)	0.0123 (13)	0.0119 (13)	−0.0009 (11)	−0.0022 (10)	−0.0003 (10)
O40	0.0120 (13)	0.0124 (14)	0.0174 (14)	−0.0050 (11)	−0.0018 (11)	−0.0050 (11)
O41	0.0116 (13)	0.0121 (13)	0.0140 (13)	−0.0041 (11)	−0.0005 (11)	−0.0042 (11)
O90	0.0168 (15)	0.0183 (15)	0.0248 (16)	−0.0097 (12)	0.0010 (12)	−0.0063 (13)
N1	0.0075 (14)	0.0113 (15)	0.0109 (15)	−0.0017 (12)	−0.0027 (12)	−0.0003 (12)
N2	0.0062 (14)	0.0081 (15)	0.0136 (15)	−0.0026 (12)	−0.0040 (12)	−0.0017 (12)
N3	0.0091 (15)	0.0101 (15)	0.0142 (16)	−0.0046 (12)	−0.0015 (12)	−0.0023 (12)
C1	0.0090 (17)	0.0116 (18)	0.0100 (17)	−0.0039 (14)	−0.0001 (14)	−0.0004 (14)
C2	0.0106 (17)	0.0122 (18)	0.0126 (18)	−0.0041 (14)	−0.0040 (14)	−0.0022 (14)
C3	0.0095 (17)	0.0091 (17)	0.0128 (18)	−0.0035 (14)	−0.0036 (14)	0.0008 (14)
C4	0.019 (2)	0.0152 (19)	0.0095 (17)	−0.0062 (16)	−0.0027 (15)	0.0001 (15)
C5	0.020 (2)	0.0149 (19)	0.0112 (18)	−0.0061 (16)	−0.0019 (15)	−0.0052 (15)
C6	0.0157 (19)	0.0077 (17)	0.0169 (19)	−0.0046 (15)	−0.0031 (15)	−0.0006 (14)
C7	0.0126 (18)	0.0165 (19)	0.0117 (18)	−0.0037 (15)	−0.0004 (14)	−0.0041 (15)
C8	0.022 (2)	0.015 (2)	0.0118 (18)	−0.0031 (16)	−0.0012 (16)	0.0041 (15)
C9	0.021 (2)	0.0093 (18)	0.020 (2)	−0.0053 (16)	0.0039 (17)	0.0028 (15)
C10	0.0171 (19)	0.0086 (17)	0.0157 (19)	−0.0052 (15)	0.0001 (15)	−0.0021 (14)
C11	0.0096 (17)	0.0092 (17)	0.0145 (18)	−0.0015 (14)	−0.0024 (14)	−0.0031 (14)
C12	0.0095 (16)	0.0093 (17)	0.0076 (16)	−0.0052 (13)	−0.0054 (13)	0.0025 (13)
C13	0.0083 (16)	0.0064 (16)	0.0128 (17)	−0.0030 (13)	−0.0040 (14)	−0.0010 (13)
C14	0.0091 (17)	0.0085 (17)	0.0132 (18)	−0.0043 (14)	−0.0004 (14)	−0.0008 (14)
C15	0.0141 (18)	0.0119 (18)	0.0112 (18)	−0.0044 (15)	−0.0009 (14)	−0.0017 (14)
C16	0.0108 (17)	0.0112 (18)	0.0151 (19)	−0.0006 (14)	−0.0013 (15)	0.0028 (15)
C17	0.0165 (19)	0.0083 (18)	0.018 (2)	−0.0044 (15)	0.0008 (16)	−0.0030 (15)
C18	0.0115 (18)	0.0140 (19)	0.0154 (19)	−0.0063 (15)	0.0012 (15)	−0.0040 (15)

Geometric parameters (Å, º) top

Ni1—N2	2.011 (3)	C1—C2	1.402 (5)
Ni1—O41	2.016 (3)	C2—C3	1.393 (5)
Ni1—N1	2.076 (3)	C2—H2	0.9300
Ni1—O40	2.082 (3)	C3—C4	1.403 (5)
Ni1—O1	2.082 (3)	C4—C5	1.385 (6)
Ni1—N3	2.089 (3)	C4—H4	0.9300
P1—O1	1.516 (3)	C5—C6	1.385 (6)
P1—O3	1.525 (3)	C5—H5	0.9300
P1—O2	1.566 (3)	C6—H6	0.9300
P1—C1	1.795 (4)	C7—C8	1.377 (6)
P2—O4	1.504 (3)	C7—H7A	0.9300
P2—O6	1.515 (3)	C8—C9	1.380 (6)
P2—O5	1.574 (3)	C8—H8A	0.9300
P2—C3	1.805 (4)	C9—C10	1.387 (6)
O2—H2'	0.8200	C9—H9	0.9300
O5—H5'	0.8200	C10—C11	1.388 (5)
O40—H40A	0.8445	C10—H10	0.9300
O40—H40B	0.8824	C11—C12	1.489 (5)
O41—H41A	0.8831	C12—C13ⁱ	1.406 (5)
O41—H41B	0.8318	C13—C12ⁱ	1.406 (5)
O90—H90A	0.9213	C13—C14	1.504 (5)
O90—H90B	0.9235	C14—C15	1.386 (5)
N1—C7	1.342 (5)	C15—C16	1.392 (5)
N1—C11	1.353 (5)	C15—H15	0.9300
N2—C13	1.336 (5)	C16—C17	1.388 (6)
N2—C12	1.336 (5)	C16—H16	0.9300
N3—C18	1.339 (5)	C17—C18	1.382 (6)
N3—C14	1.355 (5)	C17—H17	0.9300
C1—C6	1.394 (5)	C18—H18	0.9300

N2—Ni1—O41	174.66 (12)	C3—C2—H2	119.6
N2—Ni1—N1	78.70 (13)	C1—C2—H2	119.6
O41—Ni1—N1	96.31 (12)	C2—C3—C4	119.1 (4)
N2—Ni1—O40	92.64 (12)	C2—C3—P2	120.8 (3)
O41—Ni1—O40	88.91 (11)	C4—C3—P2	120.1 (3)
N1—Ni1—O40	86.27 (12)	C5—C4—C3	120.2 (4)
N2—Ni1—O1	87.69 (12)	C5—C4—H4	119.9
O41—Ni1—O1	91.29 (11)	C3—C4—H4	119.9
N1—Ni1—O1	99.42 (11)	C4—C5—C6	120.4 (4)
O40—Ni1—O1	174.25 (11)	C4—C5—H5	119.8
N2—Ni1—N3	78.95 (13)	C6—C5—H5	119.8
O41—Ni1—N3	106.20 (12)	C5—C6—C1	120.5 (4)
N1—Ni1—N3	156.87 (13)	C5—C6—H6	119.7
O40—Ni1—N3	88.87 (12)	C1—C6—H6	119.7
O1—Ni1—N3	85.55 (12)	N1—C7—C8	122.5 (4)
O1—P1—O3	112.44 (16)	N1—C7—H7A	118.7
O1—P1—O2	112.43 (16)	C8—C7—H7A	118.7
O3—P1—O2	110.23 (15)	C7—C8—C9	119.0 (4)
O1—P1—C1	107.08 (17)	C7—C8—H8A	120.5
O3—P1—C1	110.95 (16)	C9—C8—H8A	120.5
O2—P1—C1	103.31 (17)	C8—C9—C10	119.2 (4)
O4—P2—O6	115.53 (16)	C8—C9—H9	120.4
O4—P2—O5	108.24 (16)	C10—C9—H9	120.4
O6—P2—O5	110.12 (16)	C9—C10—C11	118.9 (4)
O4—P2—C3	109.86 (17)	C9—C10—H10	120.6
O6—P2—C3	106.30 (17)	C11—C10—H10	120.6
O5—P2—C3	106.41 (17)	N1—C11—C10	121.7 (4)
P1—O1—Ni1	133.25 (16)	N1—C11—C12	113.1 (3)
P1—O2—H2'	109.5	C10—C11—C12	125.1 (3)
P2—O5—H5'	109.5	N2—C12—C13ⁱ	117.7 (3)
Ni1—O40—H40A	116.6	N2—C12—C11	112.5 (3)
Ni1—O40—H40B	115.1	C13ⁱ—C12—C11	129.9 (3)
H40A—O40—H40B	106.5	N2—C13—C12ⁱ	118.1 (3)
Ni1—O41—H41A	109.6	N2—C13—C14	112.0 (3)
Ni1—O41—H41B	112.7	C12ⁱ—C13—C14	129.8 (3)
H41A—O41—H41B	117.7	N3—C14—C15	122.0 (3)
H90A—O90—H90B	106.4	N3—C14—C13	113.7 (3)
C7—N1—C11	118.6 (3)	C15—C14—C13	124.0 (3)
C7—N1—Ni1	124.9 (3)	C14—C15—C16	118.5 (4)
C11—N1—Ni1	113.8 (3)	C14—C15—H15	120.7
C13—N2—C12	124.1 (3)	C16—C15—H15	120.7
C13—N2—Ni1	116.3 (2)	C17—C16—C15	119.4 (4)
C12—N2—Ni1	116.6 (2)	C17—C16—H16	120.3
C18—N3—C14	118.6 (3)	C15—C16—H16	120.3
C18—N3—Ni1	126.3 (3)	C18—C17—C16	118.6 (4)
C14—N3—Ni1	113.3 (2)	C18—C17—H17	120.7
C6—C1—C2	118.9 (3)	C16—C17—H17	120.7
C6—C1—P1	119.3 (3)	N3—C18—C17	122.6 (4)
C2—C1—P1	121.6 (3)	N3—C18—H18	118.7
C3—C2—C1	120.9 (3)	C17—C18—H18	118.7

O3—P1—O1—Ni1	−179.15 (19)	O4—P2—C3—C4	168.7 (3)
O2—P1—O1—Ni1	55.7 (3)	O6—P2—C3—C4	−65.6 (3)
C1—P1—O1—Ni1	−57.0 (3)	O5—P2—C3—C4	51.8 (4)
N2—Ni1—O1—P1	−64.4 (2)	C2—C3—C4—C5	−0.7 (6)
O41—Ni1—O1—P1	110.4 (2)	P2—C3—C4—C5	177.4 (3)
N1—Ni1—O1—P1	13.8 (2)	C3—C4—C5—C6	0.8 (6)
N3—Ni1—O1—P1	−143.5 (2)	C4—C5—C6—C1	−0.4 (6)
N2—Ni1—N1—C7	−166.2 (3)	C2—C1—C6—C5	−0.1 (6)
O41—Ni1—N1—C7	15.7 (3)	P1—C1—C6—C5	174.7 (3)
O40—Ni1—N1—C7	−72.8 (3)	C11—N1—C7—C8	−0.8 (6)
O1—Ni1—N1—C7	108.1 (3)	Ni1—N1—C7—C8	159.6 (3)
N3—Ni1—N1—C7	−151.1 (3)	N1—C7—C8—C9	−2.0 (6)
N2—Ni1—N1—C11	−5.1 (3)	C7—C8—C9—C10	2.3 (6)
O41—Ni1—N1—C11	176.9 (3)	C8—C9—C10—C11	0.0 (6)
O40—Ni1—N1—C11	88.4 (3)	C7—N1—C11—C10	3.2 (6)
O1—Ni1—N1—C11	−90.8 (3)	Ni1—N1—C11—C10	−159.2 (3)
N3—Ni1—N1—C11	10.1 (5)	C7—N1—C11—C12	−179.9 (3)
N1—Ni1—N2—C13	−171.4 (3)	Ni1—N1—C11—C12	17.7 (4)
O40—Ni1—N2—C13	103.0 (3)	C9—C10—C11—N1	−2.8 (6)
O1—Ni1—N2—C13	−71.3 (3)	C9—C10—C11—C12	−179.3 (4)
N3—Ni1—N2—C13	14.6 (3)	C13—N2—C12—C13ⁱ	2.5 (6)
N1—Ni1—N2—C12	−10.2 (3)	Ni1—N2—C12—C13ⁱ	−157.1 (3)
O40—Ni1—N2—C12	−95.8 (3)	C13—N2—C12—C11	−178.3 (3)
O1—Ni1—N2—C12	89.9 (3)	Ni1—N2—C12—C11	22.1 (4)
N3—Ni1—N2—C12	175.8 (3)	N1—C11—C12—N2	−26.0 (4)
N2—Ni1—N3—C18	165.3 (3)	C10—C11—C12—N2	150.7 (4)
O41—Ni1—N3—C18	−16.1 (3)	N1—C11—C12—C13ⁱ	153.1 (4)
N1—Ni1—N3—C18	150.2 (3)	C10—C11—C12—C13ⁱ	−30.2 (6)
O40—Ni1—N3—C18	72.4 (3)	C12—N2—C13—C12ⁱ	−2.5 (6)
O1—Ni1—N3—C18	−106.2 (3)	Ni1—N2—C13—C12ⁱ	157.1 (3)
N2—Ni1—N3—C14	0.5 (3)	C12—N2—C13—C14	174.8 (3)
O41—Ni1—N3—C14	179.0 (2)	Ni1—N2—C13—C14	−25.5 (4)
N1—Ni1—N3—C14	−14.6 (5)	C18—N3—C14—C15	−5.4 (5)
O40—Ni1—N3—C14	−92.4 (3)	Ni1—N3—C14—C15	160.7 (3)
O1—Ni1—N3—C14	89.0 (3)	C18—N3—C14—C13	−179.6 (3)
O1—P1—C1—C6	−51.1 (3)	Ni1—N3—C14—C13	−13.5 (4)
O3—P1—C1—C6	72.0 (3)	N2—C13—C14—N3	25.5 (4)
O2—P1—C1—C6	−169.9 (3)	C12ⁱ—C13—C14—N3	−157.6 (4)
O1—P1—C1—C2	123.6 (3)	N2—C13—C14—C15	−148.6 (4)
O3—P1—C1—C2	−113.4 (3)	C12ⁱ—C13—C14—C15	28.3 (6)
O2—P1—C1—C2	4.7 (4)	N3—C14—C15—C16	4.3 (6)
C6—C1—C2—C3	0.2 (6)	C13—C14—C15—C16	178.0 (4)
P1—C1—C2—C3	−174.5 (3)	C14—C15—C16—C17	0.5 (6)
C1—C2—C3—C4	0.2 (6)	C15—C16—C17—C18	−4.2 (6)
C1—C2—C3—P2	−177.9 (3)	C14—N3—C18—C17	1.5 (6)
O4—P2—C3—C2	−13.2 (4)	Ni1—N3—C18—C17	−162.6 (3)
O6—P2—C3—C2	112.5 (3)	C16—C17—C18—N3	3.2 (6)
O5—P2—C3—C2	−130.2 (3)

Symmetry code: (i) −x, −y+1, −z+1.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O2—H2′···O3ⁱⁱ	0.82	1.91	2.536 (4)	132
O5—H5′···O6ⁱⁱⁱ	0.82	1.82	2.606 (4)	162
O40—H40A···O3^iv	0.84	1.95	2.784 (4)	170
O40—H40B···O4^v	0.88	1.83	2.711 (4)	175
O41—H41B···O6^v	0.83	1.82	2.625 (4)	163
O90—H90B···O4^vi	0.92	1.84	2.747 (4)	166
O41—H41A···O90	0.88	1.83	2.643 (4)	151
O90—H90A···O1	0.92	1.92	2.780 (4)	154

Symmetry codes: (ii) −x+1, −y+1, −z+1; (iii) −x+1, −y, −z+2; (iv) x−1, y, z; (v) x−1, y+1, z; (vi) x, y+1, z.

Experimental details

Crystal data
Chemical formula	[Ni₂(C₆H₆O₆P₂)₂(C₂₄H₁₆N₆)(H₂O)₄]·2H₂O
M_r	1086.04
Crystal system, space group	Triclinic, P1
Temperature (K)	298
a, b, c (Å)	7.9702 (6), 10.0785 (8), 14.0960 (12)
α, β, γ (°)	85.386 (2), 81.707 (1), 69.364 (1)
V (Å³)	1048.03 (15)
Z	1
Radiation type	Mo Kα
µ (mm⁻¹)	1.14
Crystal size (mm)	0.20 × 0.14 × 0.11

Data collection
Diffractometer	Bruker APEX CCD area-detector
Absorption correction	Multi-scan (SADABS; Bruker, 1998)
T_min, T_max	0.804, 0.885
No. of measured, independent and observed [I > 2σ(I)] reflections	10484, 5044, 4821
R_int	0.023
(sin θ/λ)_max (Å⁻¹)	0.662

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.066, 0.133, 1.32
No. of reflections	5044
No. of parameters	304
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.91, −0.80

Computer programs: SMART (Bruker, 1998), SAINT (Bruker, 1998), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), DIAMOND (Brandenburg & Putz, 1999), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O2—H2'···O3ⁱ	0.82	1.91	2.536 (4)	131.9
O5—H5'···O6ⁱⁱ	0.82	1.82	2.606 (4)	161.6
O40—H40A···O3ⁱⁱⁱ	0.84	1.95	2.784 (4)	169.9
O40—H40B···O4^iv	0.88	1.83	2.711 (4)	174.9
O41—H41B···O6^iv	0.83	1.82	2.625 (4)	162.9
O90—H90B···O4^v	0.92	1.84	2.747 (4)	166.1
O41—H41A···O90	0.88	1.83	2.643 (4)	151.2
O90—H90A···O1	0.92	1.92	2.780 (4)	153.8

Symmetry codes: (i) −x+1, −y+1, −z+1; (ii) −x+1, −y, −z+2; (iii) x−1, y, z; (iv) x−1, y+1, z; (v) x, y+1, z.

Acknowledgements

This work was supported by a grant from the National Science Foundation, CHE-0907787.

References

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