Poly[bis­[μ2-8-ethyl-5-oxo-2-(piperazin-1-yl)-5,8-dihydro­pyrido[2,3-d]pyrimidine-6-carboxyl­ato]nickel(II)]

An, Z.; Zhu, L.

doi:10.1107/S1600536809055408

metal-organic compounds

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ISSN: 2056-9890

Volume 66| Part 2| February 2010| Page m123

https://doi.org/10.1107/S1600536809055408

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Poly[bis[μ₂-8-ethyl-5-oxo-2-(piperazin-1-yl)-5,8-dihydropyrido[2,3-d]pyrimidine-6-carboxylato]nickel(II)]

Zhe An ^a ^* and Ling Zhu ^a

^aSchool of Chemistry and Life Science, Maoming University, Maoming 525000, People's Republic of China
^*Correspondence e-mail: anzhe6409@sina.com

(Received 22 December 2009; accepted 24 December 2009; online 9 January 2010)

The title compound, [Ni(C₁₄H₁₆N₅O₃)₂]_n or [Ni(ppa)₂]_n, where ppa is 8-ethyl-5-oxo-2-(piperazin-1-yl)-5,8-dihydropyrido[2,3-d]pyrimidine-6-carboxylate, was synthesized under hydrothermal conditions. The Ni^II atom (site symmetry $[\overline{1}]$ ) exhibits a distorted trans-NiN₂O₄ octahedral geometry defined by two monodentate N-bonded and two bidentate O,O′-bonded ppa monoanions. The extended two-dimensional structure is a square grid. An intermolecular N—H⋯O hydrogen bond occurs.

Related literature

For manganese, cobalt and zinc complexes of the ppa anion, see: Huang et al. (2008 ); Xu et al. (2009 ); Qi et al. (2009 ), respectively. For background to the medicinal uses of pipemidic acid, see: Mizuki et al. (1996 ).

Experimental

Crystal data

[Ni(C₁₄H₁₆N₅O₃)₂]
M_r = 663.35
Monoclinic, P 2₁ /c
a = 6.1249 (6) Å
b = 21.250 (2) Å
c = 12.5511 (12) Å
β = 101.846 (2)°
V = 1598.8 (3) Å³
Z = 2
Mo Kα radiation
μ = 0.66 mm⁻¹
T = 296 K
0.43 × 0.28 × 0.22 mm

Data collection

Bruker APEXII CCD diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2004 ) T_min = 0.764, T_max = 0.868
7593 measured reflections
2762 independent reflections
2389 reflections with I > 2σ(I)
R_int = 0.034

Refinement

R[F² > 2σ(F²)] = 0.066
wR(F²) = 0.199
S = 1.00
2762 reflections
209 parameters
1 restraint
H-atom parameters not refined
Δρ_max = 0.89 e Å⁻³
Δρ_min = −0.39 e Å⁻³

Table 1
Selected bond lengths (Å)

Ni1—O2	2.013 (3)
Ni1—O1	2.051 (3)
Ni1—N5ⁱ	2.207 (3)
Symmetry code: (i) $[-x, y+{\script{1\over 2}}, -z+{\script{1\over 2}}]$ .

Table 2
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N5—H5N⋯O3ⁱⁱ	0.90 (4)	2.29 (4)	3.161 (5)	163 (5)
Symmetry code: (ii) $[-x+1, y-{\script{1\over 2}}, -z+{\script{1\over 2}}]$ .

Data collection: APEX2 (Bruker, 2004); cell refinement: SAINT-Plus (Bruker, 2004); data reduction: SAINT-Plus; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL.

Supporting information

Crystal structure: contains datablocks I, global. DOI: https://doi.org/10.1107/S1600536809055408/hb5292sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536809055408/hb5292Isup2.hkl

checkCIF report

Comment top

Pipemidic acid (Hppa, C₁₄H₁₆N₅O₃, 8-Ethyl-5,8-dihydro-5-oxo-2- (1-piperazinyl)-pyrido(2,3-d)-pyrimidine-6-carboxylic acid) is member of a class of quinolones used to treat infections (Mizuki et al., 1996). The manganese, cobalt and zinc complexes of the ppa anion have been reported (Huang et al., 2008; Xu et al. 2009; Qi Xu et al.2009). The title nickel(II) complex, (I), is reported here (Fig. 1).

The nickel(II) atom is coordinated by four oxygen atoms and two N atoms from four ppa ligands (two monodentate-N and two O,O-bidentate) to form a square grid propagating in (Fig. 2).

Related literature top

For manganese, cobalt and zinc complexes of the ppa anion, see: Huang et al. (2008); Xu et al. (2009); Qi et al. (2009), respectively. For background to the medicinal uses of pipemidic acid, see: Mizuki et al. (1996).

Experimental top

A mixture of Ni(CH₃COO)₂.4H₂O (0.063 g, 0.25 mmol), Hppa (0.15 g, 0.5 mmol), sodium hydroxide (0.04 g, 1 mmol) and water (15 ml) was stirred for 30 min in air. The mixture was then transferred to a 25 ml Teflon-lined hydrothermal bomb. The bomb was kept at 443 K for 72 h under autogenous pressure. Upon cooling, green prisms of (I) were obtained from the reaction mixture.

Structure description top

The nickel(II) atom is coordinated by four oxygen atoms and two N atoms from four ppa ligands (two monodentate-N and two O,O-bidentate) to form a square grid propagating in (Fig. 2).

For manganese, cobalt and zinc complexes of the ppa anion, see: Huang et al. (2008); Xu et al. (2009); Qi et al. (2009), respectively. For background to the medicinal uses of pipemidic acid, see: Mizuki et al. (1996).

Computing details top

Data collection: APEX2 (Bruker, 2004); cell refinement: SAINT-Plus (Bruker, 2004); data reduction: SAINT-Plus (Bruker, 2004); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top

	Fig. 1. The asymmetric unit of (I), expanded to show the metal atom coordination showing 50% displacement ellipsoids.
	Fig. 2. A view of part of a two-dimensional polymeric sheet in (I) showing the square-grid connectivity.

Poly[bis[µ₂-8-ethyl-5-oxo-2-(piperazin-1-yl)-5,8- dihydropyrido[2,3-d]pyrimidine-6-carboxylato]nickel(II)] top

Crystal data top

[Ni(C₁₄H₁₆N₅O₃)₂]	F(000) = 692
M_r = 663.35	D_x = 1.378 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 3258 reflections
a = 6.1249 (6) Å	θ = 2.5–28.3°
b = 21.250 (2) Å	µ = 0.66 mm⁻¹
c = 12.5511 (12) Å	T = 296 K
β = 101.846 (2)°	Prism, green
V = 1598.8 (3) Å³	0.43 × 0.28 × 0.22 mm
Z = 2

Data collection top

Bruker APEXII CCD diffractometer	2762 independent reflections
Radiation source: fine-focus sealed tube	2389 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.034
φ and ω scans	θ_max = 25.1°, θ_min = 2.5°
Absorption correction: multi-scan (SADABS; Bruker, 2004)	h = −7→7
T_min = 0.764, T_max = 0.868	k = −25→23
7593 measured reflections	l = −14→9

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) = 0.199	H-atom parameters not refined
S = 1.00	w = 1/[σ²(F_o²) + (0.122P)² + 2.8827P] where P = (F_o² + 2F_c²)/3
2762 reflections	(Δ/σ)_max = 0.007
209 parameters	Δρ_max = 0.89 e Å⁻³
1 restraint	Δρ_min = −0.39 e Å⁻³

Crystal data top

[Ni(C₁₄H₁₆N₅O₃)₂]	V = 1598.8 (3) Å³
M_r = 663.35	Z = 2
Monoclinic, P2₁/c	Mo Kα radiation
a = 6.1249 (6) Å	µ = 0.66 mm⁻¹
b = 21.250 (2) Å	T = 296 K
c = 12.5511 (12) Å	0.43 × 0.28 × 0.22 mm
β = 101.846 (2)°

Data collection top

Bruker APEXII CCD diffractometer	2762 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2004)	2389 reflections with I > 2σ(I)
T_min = 0.764, T_max = 0.868	R_int = 0.034
7593 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.066	1 restraint
wR(F²) = 0.199	H-atom parameters not refined
S = 1.00	Δρ_max = 0.89 e Å⁻³
2762 reflections	Δρ_min = −0.39 e Å⁻³
209 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	0.5000	0.5000	0.5000	0.0219 (3)
C1	0.7141 (7)	0.47283 (19)	0.3080 (4)	0.0293 (9)
C2	0.5607 (7)	0.41749 (19)	0.2771 (3)	0.0310 (9)
C3	0.3908 (6)	0.39745 (18)	0.3348 (3)	0.0250 (8)
C4	0.2685 (7)	0.34232 (19)	0.2900 (3)	0.0287 (9)
C5	0.0880 (8)	0.3175 (2)	0.3310 (4)	0.0380 (11)
H5	0.0416	0.3397	0.3863	0.046*
C6	0.0596 (7)	0.2340 (2)	0.2186 (4)	0.0310 (9)
C7	0.3168 (7)	0.3083 (2)	0.2024 (4)	0.0333 (10)
C8	0.5934 (9)	0.3829 (2)	0.1908 (4)	0.0448 (12)
H8	0.7017	0.3972	0.1544	0.054*
C9	0.5451 (11)	0.2956 (3)	0.0587 (6)	0.0655 (18)
H9A	0.7027	0.3014	0.0599	0.079*
H9B	0.5179	0.2510	0.0652	0.079*
C10	0.4140 (17)	0.3190 (6)	−0.0446 (8)	0.0426 (8)
H10A	0.2601	0.3080	−0.0501	0.168*
H10B	0.4681	0.3005	−0.1039	0.168*
H10C	0.4278	0.3640	−0.0473	0.168*
C11	−0.1716 (9)	0.1431 (2)	0.2519 (4)	0.0462 (13)
H11A	−0.2457	0.1731	0.2908	0.055*
H11B	−0.0778	0.1164	0.3051	0.055*
C12	−0.3438 (8)	0.1034 (2)	0.1784 (4)	0.0375 (10)
H12A	−0.4224	0.0785	0.2233	0.045*
H12B	−0.4517	0.1311	0.1343	0.045*
C13	0.0646 (7)	0.1360 (2)	0.1181 (4)	0.0330 (10)
H13A	0.1711	0.1080	0.1622	0.040*
H13B	0.1435	0.1611	0.0735	0.040*
C14	−0.1164 (7)	0.0976 (2)	0.0452 (4)	0.0297 (9)
H14A	−0.2129	0.1259	−0.0039	0.036*
H14B	−0.0469	0.0694	0.0013	0.036*
H5N	−0.163 (7)	0.035 (2)	0.152 (3)	0.044*
N1	0.4839 (7)	0.3299 (2)	0.1527 (3)	0.0454 (11)
N2	0.2161 (6)	0.25401 (17)	0.1666 (3)	0.0354 (9)
N3	−0.0183 (7)	0.26577 (19)	0.2969 (4)	0.0427 (10)
N4	−0.0326 (6)	0.17705 (17)	0.1881 (3)	0.0327 (8)
N5	−0.2530 (5)	0.06053 (15)	0.1053 (3)	0.0262 (7)
O1	0.3477 (5)	0.42282 (13)	0.4188 (2)	0.0288 (7)
O2	0.6982 (5)	0.50474 (11)	0.3906 (2)	0.0270 (7)
O3	0.8546 (7)	0.4840 (2)	0.2525 (3)	0.0579 (11)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Ni1	0.0256 (4)	0.0139 (4)	0.0257 (4)	−0.0008 (2)	0.0040 (3)	−0.0028 (3)
C1	0.032 (2)	0.022 (2)	0.034 (2)	−0.0029 (17)	0.0055 (18)	−0.0007 (17)
C2	0.041 (2)	0.022 (2)	0.031 (2)	−0.0069 (17)	0.0088 (18)	−0.0052 (17)
C3	0.0291 (19)	0.0178 (18)	0.026 (2)	−0.0008 (15)	0.0020 (16)	−0.0002 (16)
C4	0.034 (2)	0.023 (2)	0.030 (2)	−0.0027 (17)	0.0072 (17)	−0.0047 (17)
C5	0.040 (2)	0.032 (2)	0.046 (3)	−0.0112 (19)	0.019 (2)	−0.019 (2)
C6	0.032 (2)	0.024 (2)	0.038 (2)	−0.0061 (17)	0.0082 (18)	−0.0090 (18)
C7	0.041 (2)	0.028 (2)	0.034 (2)	−0.0039 (18)	0.0117 (19)	−0.0074 (18)
C8	0.059 (3)	0.037 (3)	0.043 (3)	−0.017 (2)	0.022 (2)	−0.012 (2)
C9	0.077 (4)	0.060 (4)	0.068 (4)	−0.025 (3)	0.034 (3)	−0.018 (3)
C10	0.0396 (18)	0.047 (2)	0.0409 (17)	0.0122 (15)	0.0083 (14)	0.0059 (15)
C11	0.052 (3)	0.041 (3)	0.053 (3)	−0.025 (2)	0.028 (2)	−0.021 (2)
C12	0.039 (2)	0.031 (2)	0.045 (3)	−0.0097 (19)	0.015 (2)	−0.011 (2)
C13	0.029 (2)	0.029 (2)	0.045 (2)	−0.0055 (17)	0.0152 (19)	−0.0153 (19)
C14	0.032 (2)	0.0219 (19)	0.037 (2)	−0.0034 (16)	0.0120 (18)	−0.0042 (17)
N1	0.061 (3)	0.040 (2)	0.042 (2)	−0.025 (2)	0.026 (2)	−0.0145 (18)
N2	0.047 (2)	0.0271 (18)	0.035 (2)	−0.0156 (16)	0.0169 (17)	−0.0112 (16)
N3	0.044 (2)	0.030 (2)	0.057 (3)	−0.0140 (17)	0.0198 (19)	−0.0192 (19)
N4	0.0348 (18)	0.0239 (18)	0.042 (2)	−0.0081 (15)	0.0143 (16)	−0.0121 (16)
N5	0.0275 (17)	0.0193 (16)	0.0303 (18)	−0.0026 (13)	0.0020 (14)	−0.0004 (14)
O1	0.0317 (15)	0.0215 (14)	0.0351 (16)	−0.0043 (11)	0.0111 (12)	−0.0069 (12)
O2	0.0329 (16)	0.0184 (14)	0.0298 (16)	0.0003 (11)	0.0066 (12)	−0.0026 (11)
O3	0.069 (3)	0.061 (2)	0.055 (2)	−0.037 (2)	0.040 (2)	−0.026 (2)

Geometric parameters (Å, º) top

Ni1—O2ⁱ	2.013 (3)	C9—C10	1.464 (12)
Ni1—O2	2.013 (3)	C9—N1	1.498 (7)
Ni1—O1ⁱ	2.051 (3)	C9—H9A	0.9700
Ni1—O1	2.051 (3)	C9—H9B	0.9700
Ni1—N5ⁱⁱ	2.207 (3)	C10—H10A	0.9600
Ni1—N5ⁱⁱⁱ	2.207 (3)	C10—H10B	0.9600
C1—O3	1.236 (6)	C10—H10C	0.9600
C1—O2	1.260 (5)	C11—N4	1.472 (6)
C1—C2	1.505 (6)	C11—C12	1.509 (6)
C2—C8	1.358 (6)	C11—H11A	0.9700
C2—C3	1.448 (6)	C11—H11B	0.9700
C3—O1	1.260 (5)	C12—N5	1.480 (6)
C3—C4	1.441 (6)	C12—H12A	0.9700
C4—C7	1.398 (6)	C12—H12B	0.9700
C4—C5	1.413 (6)	C13—N4	1.450 (5)
C5—N3	1.305 (6)	C13—C14	1.522 (6)
C5—H5	0.9300	C13—H13A	0.9700
C6—N2	1.334 (6)	C13—H13B	0.9700
C6—N4	1.357 (5)	C14—N5	1.467 (5)
C6—N3	1.357 (6)	C14—H14A	0.9700
C7—N2	1.341 (6)	C14—H14B	0.9700
C7—N1	1.382 (6)	N5—Ni1^iv	2.207 (3)
C8—N1	1.348 (6)	N5—H5N	0.90 (4)
C8—H8	0.9300

O2ⁱ—Ni1—O2	180.0	C9—C10—H10B	109.5
O2ⁱ—Ni1—O1ⁱ	88.73 (11)	H10A—C10—H10B	109.5
O2—Ni1—O1ⁱ	91.27 (11)	C9—C10—H10C	109.5
O2ⁱ—Ni1—O1	91.27 (11)	H10A—C10—H10C	109.5
O2—Ni1—O1	88.73 (11)	H10B—C10—H10C	109.5
O1ⁱ—Ni1—O1	180.0	N4—C11—C12	110.6 (4)
O2ⁱ—Ni1—N5ⁱⁱ	90.14 (12)	N4—C11—H11A	109.5
O2—Ni1—N5ⁱⁱ	89.86 (12)	C12—C11—H11A	109.5
O1ⁱ—Ni1—N5ⁱⁱ	91.00 (11)	N4—C11—H11B	109.5
O1—Ni1—N5ⁱⁱ	89.00 (11)	C12—C11—H11B	109.5
O2ⁱ—Ni1—N5ⁱⁱⁱ	89.86 (12)	H11A—C11—H11B	108.1
O2—Ni1—N5ⁱⁱⁱ	90.14 (12)	N5—C12—C11	114.8 (4)
O1ⁱ—Ni1—N5ⁱⁱⁱ	89.00 (11)	N5—C12—H12A	108.6
O1—Ni1—N5ⁱⁱⁱ	91.00 (11)	C11—C12—H12A	108.6
N5ⁱⁱ—Ni1—N5ⁱⁱⁱ	180.0	N5—C12—H12B	108.6
O3—C1—O2	122.8 (4)	C11—C12—H12B	108.6
O3—C1—C2	118.4 (4)	H12A—C12—H12B	107.6
O2—C1—C2	118.9 (4)	N4—C13—C14	110.4 (3)
C8—C2—C3	118.6 (4)	N4—C13—H13A	109.6
C8—C2—C1	116.2 (4)	C14—C13—H13A	109.6
C3—C2—C1	125.1 (4)	N4—C13—H13B	109.6
O1—C3—C4	119.5 (4)	C14—C13—H13B	109.6
O1—C3—C2	126.1 (4)	H13A—C13—H13B	108.1
C4—C3—C2	114.4 (4)	N5—C14—C13	113.6 (4)
C7—C4—C5	113.6 (4)	N5—C14—H14A	108.8
C7—C4—C3	123.4 (4)	C13—C14—H14A	108.8
C5—C4—C3	122.9 (4)	N5—C14—H14B	108.8
N3—C5—C4	124.7 (4)	C13—C14—H14B	108.8
N3—C5—H5	117.6	H14A—C14—H14B	107.7
C4—C5—H5	117.6	C8—N1—C7	118.6 (4)
N2—C6—N4	116.5 (4)	C8—N1—C9	119.9 (4)
N2—C6—N3	126.2 (4)	C7—N1—C9	121.5 (4)
N4—C6—N3	117.4 (4)	C6—N2—C7	115.9 (4)
N2—C7—N1	117.8 (4)	C5—N3—C6	115.5 (4)
N2—C7—C4	123.5 (4)	C6—N4—C13	120.5 (4)
N1—C7—C4	118.6 (4)	C6—N4—C11	122.5 (4)
N1—C8—C2	126.3 (5)	C13—N4—C11	113.0 (3)
N1—C8—H8	116.9	C14—N5—C12	108.4 (3)
C2—C8—H8	116.9	C14—N5—Ni1^iv	113.5 (2)
C10—C9—N1	110.6 (7)	C12—N5—Ni1^iv	115.6 (2)
C10—C9—H9A	109.5	C14—N5—H5N	109 (3)
N1—C9—H9A	109.5	C12—N5—H5N	103 (4)
C10—C9—H9B	109.5	Ni1^iv—N5—H5N	107 (3)
N1—C9—H9B	109.5	C3—O1—Ni1	127.3 (3)
H9A—C9—H9B	108.1	C1—O2—Ni1	134.0 (3)
C9—C10—H10A	109.5

O3—C1—C2—C8	1.5 (7)	N3—C6—N2—C7	5.9 (7)
O2—C1—C2—C8	−176.7 (4)	N1—C7—N2—C6	178.4 (4)
O3—C1—C2—C3	178.7 (4)	C4—C7—N2—C6	1.4 (7)
O2—C1—C2—C3	0.6 (6)	C4—C5—N3—C6	2.0 (8)
C8—C2—C3—O1	176.7 (4)	N2—C6—N3—C5	−7.5 (8)
C1—C2—C3—O1	−0.5 (7)	N4—C6—N3—C5	174.0 (4)
C8—C2—C3—C4	−1.8 (6)	N2—C6—N4—C13	11.1 (6)
C1—C2—C3—C4	−178.9 (4)	N3—C6—N4—C13	−170.2 (4)
O1—C3—C4—C7	−174.8 (4)	N2—C6—N4—C11	167.2 (4)
C2—C3—C4—C7	3.8 (6)	N3—C6—N4—C11	−14.2 (7)
O1—C3—C4—C5	5.1 (6)	C14—C13—N4—C6	−147.5 (4)
C2—C3—C4—C5	−176.4 (4)	C14—C13—N4—C11	54.4 (5)
C7—C4—C5—N3	4.1 (7)	C12—C11—N4—C6	149.6 (4)
C3—C4—C5—N3	−175.8 (5)	C12—C11—N4—C13	−52.7 (6)
C5—C4—C7—N2	−5.8 (7)	C13—C14—N5—C12	54.2 (5)
C3—C4—C7—N2	174.0 (4)	C13—C14—N5—Ni1^iv	−176.1 (3)
C5—C4—C7—N1	177.2 (4)	C11—C12—N5—C14	−53.0 (5)
C3—C4—C7—N1	−2.9 (7)	C11—C12—N5—Ni1^iv	178.4 (3)
C3—C2—C8—N1	−1.0 (8)	C4—C3—O1—Ni1	178.8 (3)
C1—C2—C8—N1	176.4 (5)	C2—C3—O1—Ni1	0.4 (6)
N4—C11—C12—N5	52.7 (6)	O2ⁱ—Ni1—O1—C3	179.7 (3)
N4—C13—C14—N5	−56.3 (5)	O2—Ni1—O1—C3	−0.3 (3)
C2—C8—N1—C7	2.0 (8)	N5ⁱⁱ—Ni1—O1—C3	89.6 (3)
C2—C8—N1—C9	−177.7 (6)	N5ⁱⁱⁱ—Ni1—O1—C3	−90.4 (3)
N2—C7—N1—C8	−177.2 (5)	O3—C1—O2—Ni1	−178.7 (4)
C4—C7—N1—C8	0.0 (7)	C2—C1—O2—Ni1	−0.7 (6)
N2—C7—N1—C9	2.6 (8)	O1ⁱ—Ni1—O2—C1	−179.5 (4)
C4—C7—N1—C9	179.8 (5)	O1—Ni1—O2—C1	0.5 (4)
C10—C9—N1—C8	−89.8 (8)	N5ⁱⁱ—Ni1—O2—C1	−88.5 (4)
C10—C9—N1—C7	90.4 (7)	N5ⁱⁱⁱ—Ni1—O2—C1	91.5 (4)
N4—C6—N2—C7	−175.6 (4)

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

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N5—H5N···O3^v	0.90 (4)	2.29 (4)	3.161 (5)	163 (5)

Symmetry code: (v) −x+1, y−1/2, −z+1/2.

Experimental details

Crystal data
Chemical formula	[Ni(C₁₄H₁₆N₅O₃)₂]
M_r	663.35
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	296
a, b, c (Å)	6.1249 (6), 21.250 (2), 12.5511 (12)
β (°)	101.846 (2)
V (Å³)	1598.8 (3)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	0.66
Crystal size (mm)	0.43 × 0.28 × 0.22

Data collection
Diffractometer	Bruker APEXII CCD
Absorption correction	Multi-scan (SADABS; Bruker, 2004)
T_min, T_max	0.764, 0.868
No. of measured, independent and observed [I > 2σ(I)] reflections	7593, 2762, 2389
R_int	0.034
(sin θ/λ)_max (Å⁻¹)	0.597

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.066, 0.199, 1.00
No. of reflections	2762
No. of parameters	209
No. of restraints	1
H-atom treatment	H-atom parameters not refined
Δρ_max, Δρ_min (e Å⁻³)	0.89, −0.39

Computer programs: APEX2 (Bruker, 2004), SAINT-Plus (Bruker, 2004), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Selected bond lengths (Å) top

Ni1—O2	2.013 (3)	Ni1—N5ⁱ	2.207 (3)
Ni1—O1	2.051 (3)

Symmetry code: (i) −x, y+1/2, −z+1/2.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N5—H5N···O3ⁱⁱ	0.90 (4)	2.29 (4)	3.161 (5)	163 (5)

Symmetry code: (ii) −x+1, y−1/2, −z+1/2.

Acknowledgements

The authors acknowledge financial support from the program for talent introduction in Guangdong Higher Education Institutions (grant No. 201191) and the scientific research start-up funds for talent introduction in Maoming University (grant No. 208058).

References

Bruker (2004). APEX2, SAINT-Plus and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA. Google Scholar
Huang, J., Hu, W.-P. & An, Z. (2008). Acta Cryst. E64, m547. Web of Science CSD CrossRef IUCr Journals Google Scholar
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Qi, X., Shao, M. & Li, C.-X. (2009). Acta Cryst. E65, m1334. Web of Science CSD CrossRef IUCr Journals Google Scholar
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. Web of Science CrossRef CAS IUCr Journals Google Scholar
Xu, W., Zhu, D.-S., Song, X.-D. & An, Z. (2009). Acta Cryst. E65, m1223. Web of Science CSD CrossRef IUCr Journals Google Scholar

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