{3,3′,5,5′-Tetra­meth­oxy-2,2′-[ethane-1,2-diylbis(nitrilo­methyl­idyne)]diphenolato}nickel(II)

Assey, G.E.; Butcher, R.J.; Gultneh, Y.

doi:10.1107/S1600536810016041

{3,3′,5,5′-Tetramethoxy-2,2′-[ethane-1,2-diylbis(nitrilomethylidyne)]diphenolato}nickel(II)

G. E. Assey, R. J. Butcher and Y. Gultneh

The title square-planar nickel complex, [Ni(C₂₀H₂₂N₂O₆)], has Ni—N and Ni—O bond lengths of 1.8448 (14)/1.8478 (14) and 1.8536 (12)/1.8520 (12) Å. There is a slight twist in the two benzene rings at each end of the complex [dihedral angle = 11.11 (5)°]. All the atoms of the methoxy substitutents are in the plane of the ring to which they are attached except for one which deviates slightly [0.365 (3) Å]. In the crystal, weak C—H

O intermolecular interactions connect the molecules.

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Supporting information

	Crystallographic Information File (CIF) https://doi.org/10.1107/S1600536810016041/bt5260sup1.cif Contains datablocks I, global
	Structure factor file (CIF format) https://doi.org/10.1107/S1600536810016041/bt5260Isup2.hkl Contains datablock I

CCDC reference: 781188

checkCIF report

Key indicators

Single-crystal X-ray study
T = 110 K
Mean (C-C) = 0.002 Å
R factor = 0.036
wR factor = 0.098
Data-to-parameter ratio = 13.5

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT910_ALERT_3_C Missing # of FCF Reflections Below Th(Min) .....          1
PLAT911_ALERT_3_C Missing # FCF Refl Between THmin & STh/L=  0.600          5
PLAT913_ALERT_3_C Missing # of Very Strong Reflections in FCF ....          1
PLAT480_ALERT_4_C Long H...A H-Bond Reported H8B    ..  O2      ..       2.61 Ang.
PLAT912_ALERT_4_C Missing # of FCF Reflections Above STh/L=  0.600        119

Alert level G
PLAT710_ALERT_4_G Delete 1-2-3 or 2-3-4 Linear Torsion Angle ... #          2
            N2  -NI  -O1  -C1    -98.50  1.10   1.555   1.555   1.555   1.555
PLAT710_ALERT_4_G Delete 1-2-3 or 2-3-4 Linear Torsion Angle ... #          4
            N1  -NI  -O2  -C16  -105.10  1.20   1.555   1.555   1.555   1.555
PLAT710_ALERT_4_G Delete 1-2-3 or 2-3-4 Linear Torsion Angle ... #          8
            O2  -NI  -N1  -C7    -73.90  1.20   1.555   1.555   1.555   1.555
PLAT710_ALERT_4_G Delete 1-2-3 or 2-3-4 Linear Torsion Angle ... #         11
            O2  -NI  -N1  -C8    106.10  1.20   1.555   1.555   1.555   1.555
PLAT710_ALERT_4_G Delete 1-2-3 or 2-3-4 Linear Torsion Angle ... #         15
            O1  -NI  -N2  -C10   -89.00  1.10   1.555   1.555   1.555   1.555
PLAT710_ALERT_4_G Delete 1-2-3 or 2-3-4 Linear Torsion Angle ... #         18
            O1  -NI  -N2  -C9     91.80  1.10   1.555   1.555   1.555   1.555

   0 ALERT level A = In general: serious problem
   0 ALERT level B = Potentially serious problem
   5 ALERT level C = Check and explain
   6 ALERT level G = General alerts; check

   0 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   0 ALERT type 2 Indicator that the structure model may be wrong or deficient
   3 ALERT type 3 Indicator that the structure quality may be low
   8 ALERT type 4 Improvement, methodology, query or suggestion
   0 ALERT type 5 Informative message, check

Comment top

Complexes of Ni(II) with N₂O₂ Schiff bases derived from salicylaldehyde have been studied for a long time as homogeneous catalysts due to their high activity and selectivity (Silva et al. 2002, Santos et al. 2000). These types of complexes have been described in the literature as catalytically active in oxidation and reduction reactions both as homogeneous and heterogeneous catalysts (Yoon & Burrows, 1988). Other areas where coordination chemistry has found application are in the areas of molecular adsorption, liquid-liquid extraction, ion exchange and metalloenzymes. They have been designed as potential transition metal host systems in host-guest chemistry in the similar way to that of enzyme substrate.

The importance of nickel salen complexes with aromatic substituents range from biological (Bal and Ülküseven, 2004), activation of O₂ under very mild conditions (Soto-Garrodo, & Salas-Reyes, 2000) and mesogenic properties of substituted complexes. (Blake et al. 1995) reported metallomesogens based on nickel alkyl and alkoxy substituted salen.

The central Ni is in a square planar coordination environment of O1 O2, N1 and N2 with rms deviation of 0.0461 (6) Å (deviation from plane for Ni of 0.0034 (7) Å). The Ni—N and Ni—O bond distances are in the normal range for Ni-salen type complexes (Allen et al., 1987) at 1.8448 (14), and 1.8478 (14) Å for Ni—N and 1.8536 (12) Å and 1.8520 (12) Å for Ni—O. There is a slight twist in the two phenyl rings at each end of the complex (dihedral angle of 11.11 (5)°. All the atoms of the methoxy substitutents are in the plane of the ring to which they are attached except C19 which deviates slightly (0.365 (3) °). There are weak C—H···O intermolecular interactions connecting the molecules in the solid state.

Related literature top

For nickel–salen complexes with aromatic substituents, see: Bal & Ülküseven (2004). For their activation of O₂, see: Soto-Garrodo & Salas-Reyes (2000); For their catalytic activity: Silva et al. (2002); Santos et al. (2000); Yoon & Burrows (1988). For the mesogenic properties of substituted complexes, see: Blake et al. (1995). For bond-length data, see: Allen et al. (1987).

Experimental top

The ligand synthesis was accomplished by adding a solution of (2 g, 33.3 mmol) ethylenediamine in 25 mls of methanol to a solution of (12.13 g, 66.6 mmol) 4,6-dimethoxysalicylaldehyde in 40 ml of methanol. The mixture was refluxed overnight while stirring. Then the mixture was evaporated under reduced pressure to afford yellow solids.

The complex was synthesized by mixing a solution of (0.38 g, 1 mmol) N,N-ethylenebis(4,6-dimethoxysalicylaldimine) in 5 ml of CH₂Cl₂ with a solution of (0.29 g, 1 mmol) nickel nitrate hexahydrate in 5 ml methanol. The solution mixture was stirred for 1 hour then filtered and layered with diethyl ether for crystallization. Single crystals of X-ray quality were obtained.

Structure description top

Computing details top

Data collection: CrysAlis PRO (Oxford Diffraction, 2007); cell refinement: CrysAlis PRO (Oxford Diffraction, 2007); data reduction: CrysAlis PRO (Oxford Diffraction, 2007); 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. Diagram of the square planar nickel complex C₂₀H₂₂N₂NiO₆ showing atom labeling.
	Fig. 2. The molecular packing for C₂₀H₂₂N₂NiO₆ viewed down the a axis.

{3,3',5,5'-Tetramethoxy-2,2'-[ethane-1,2- diylbis(nitrilomethylidyne)]diphenolato}nickel(II) top

Crystal data top

[Ni(C₂₀H₂₂N₂O₆)]	F(000) = 928
M_r = 445.11	D_x = 1.617 Mg m⁻³
Monoclinic, P2₁/c	Cu Kα radiation, λ = 1.54184 Å
Hall symbol: -P 2ybc	Cell parameters from 5663 reflections
a = 7.41599 (12) Å	θ = 5.6–74.0°
b = 15.6945 (2) Å	µ = 1.91 mm⁻¹
c = 15.7203 (2) Å	T = 110 K
β = 91.9153 (13)°	Needle, red
V = 1828.67 (5) Å³	0.53 × 0.15 × 0.12 mm
Z = 4

Data collection top

Oxford Diffraction Xcalibur Ruby Gemini diffractometer	3603 independent reflections
Radiation source: Enhance (Cu) X-ray Source	3370 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.022
Detector resolution: 10.5081 pixels mm^-1	θ_max = 74.2°, θ_min = 5.6°
ω scans	h = −9→8
Absorption correction: multi-scan (CrysAlis PRO; Oxford Diffraction, 2007)	k = −11→19
T_min = 0.602, T_max = 1.000	l = −18→19
6746 measured reflections

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)] = 0.036	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.098	H-atom parameters constrained
S = 1.04	w = 1/[σ²(F_o²) + (0.0641P)² + 1.0294P] where P = (F_o² + 2F_c²)/3
3603 reflections	(Δ/σ)_max < 0.001
266 parameters	Δρ_max = 0.42 e Å⁻³
0 restraints	Δρ_min = −0.47 e Å⁻³

Crystal data top

[Ni(C₂₀H₂₂N₂O₆)]	V = 1828.67 (5) Å³
M_r = 445.11	Z = 4
Monoclinic, P2₁/c	Cu Kα radiation
a = 7.41599 (12) Å	µ = 1.91 mm⁻¹
b = 15.6945 (2) Å	T = 110 K
c = 15.7203 (2) Å	0.53 × 0.15 × 0.12 mm
β = 91.9153 (13)°

Data collection top

Oxford Diffraction Xcalibur Ruby Gemini diffractometer	3603 independent reflections
Absorption correction: multi-scan (CrysAlis PRO; Oxford Diffraction, 2007)	3370 reflections with I > 2σ(I)
T_min = 0.602, T_max = 1.000	R_int = 0.022
6746 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.036	0 restraints
wR(F²) = 0.098	H-atom parameters constrained
S = 1.04	Δρ_max = 0.42 e Å⁻³
3603 reflections	Δρ_min = −0.47 e Å⁻³
266 parameters

Special details top

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds 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
Ni	0.25525 (4)	0.522587 (16)	0.436449 (16)	0.01249 (11)
O1	0.25637 (17)	0.49637 (8)	0.32150 (7)	0.0166 (2)
O2	0.25493 (17)	0.63580 (7)	0.40321 (7)	0.0168 (2)
O3	0.36236 (18)	0.33461 (8)	0.07279 (8)	0.0209 (3)
O4	0.45100 (16)	0.20821 (7)	0.34353 (7)	0.0183 (3)
O5	0.10218 (18)	0.76296 (8)	0.66590 (7)	0.0192 (3)
O6	0.13141 (19)	0.93215 (8)	0.41651 (8)	0.0230 (3)
N1	0.26710 (19)	0.41000 (9)	0.46989 (8)	0.0143 (3)
N2	0.24084 (18)	0.54755 (10)	0.55089 (9)	0.0145 (3)
C1	0.3028 (2)	0.42368 (10)	0.28756 (10)	0.0142 (3)
C2	0.3067 (2)	0.41965 (10)	0.19756 (10)	0.0158 (3)
H2A	0.2743	0.4682	0.1643	0.019*
C3	0.3576 (2)	0.34513 (11)	0.15833 (10)	0.0163 (3)
C4	0.4124 (2)	0.27279 (11)	0.20515 (11)	0.0171 (3)
H4A	0.4539	0.2233	0.1771	0.020*
C5	0.4047 (2)	0.27513 (10)	0.29228 (11)	0.0150 (3)
C6	0.3462 (2)	0.34938 (10)	0.33579 (11)	0.0152 (3)
C7	0.3154 (2)	0.34535 (10)	0.42475 (11)	0.0145 (3)
H7A	0.3313	0.2920	0.4526	0.017*
C8	0.2141 (2)	0.39623 (11)	0.55814 (10)	0.0164 (3)
H8A	0.2732	0.3445	0.5820	0.020*
H8B	0.0818	0.3891	0.5605	0.020*
C9	0.2745 (2)	0.47426 (10)	0.60768 (11)	0.0171 (3)
H9A	0.2051	0.4801	0.6601	0.020*
H9B	0.4044	0.4702	0.6239	0.020*
C10	0.2071 (2)	0.62123 (11)	0.58443 (10)	0.0155 (3)
H10A	0.1973	0.6239	0.6445	0.019*
C11	0.1837 (2)	0.69804 (11)	0.53782 (10)	0.0155 (3)
C12	0.1328 (2)	0.77404 (11)	0.58121 (10)	0.0165 (3)
C13	0.1162 (2)	0.85044 (11)	0.53987 (11)	0.0188 (3)
H13A	0.0831	0.9005	0.5695	0.023*
C14	0.1498 (2)	0.85285 (11)	0.45184 (11)	0.0171 (3)
C15	0.1950 (2)	0.78148 (11)	0.40677 (10)	0.0165 (3)
H15A	0.2138	0.7853	0.3474	0.020*
C16	0.2134 (2)	0.70230 (10)	0.44895 (10)	0.0144 (3)
C17	0.3271 (3)	0.40816 (12)	0.02106 (11)	0.0264 (4)
H17A	0.3333	0.3925	−0.0391	0.040*
H17B	0.4174	0.4521	0.0347	0.040*
H17C	0.2065	0.4302	0.0322	0.040*
C18	0.5069 (3)	0.13184 (11)	0.30218 (12)	0.0213 (4)
H18A	0.5485	0.0903	0.3451	0.032*
H18B	0.6056	0.1450	0.2643	0.032*
H18C	0.4050	0.1080	0.2688	0.032*
C19	0.0109 (2)	0.83006 (11)	0.70858 (11)	0.0203 (4)
H19A	−0.0207	0.8109	0.7655	0.030*
H19B	−0.0992	0.8453	0.6759	0.030*
H19C	0.0901	0.8799	0.7136	0.030*
C20	0.1620 (3)	0.93901 (11)	0.32755 (12)	0.0232 (4)
H20A	0.1452	0.9983	0.3094	0.035*
H20B	0.0763	0.9025	0.2958	0.035*
H20C	0.2855	0.9209	0.3164	0.035*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Ni	0.01826 (18)	0.00876 (17)	0.01067 (17)	0.00064 (10)	0.00377 (11)	−0.00065 (9)
O1	0.0266 (6)	0.0109 (5)	0.0127 (5)	0.0024 (5)	0.0038 (4)	−0.0009 (4)
O2	0.0253 (6)	0.0111 (5)	0.0144 (6)	0.0006 (5)	0.0071 (4)	−0.0013 (4)
O3	0.0311 (7)	0.0181 (6)	0.0139 (6)	0.0004 (5)	0.0046 (5)	−0.0034 (5)
O4	0.0253 (6)	0.0112 (5)	0.0185 (6)	0.0045 (5)	0.0019 (5)	−0.0026 (4)
O5	0.0298 (7)	0.0148 (6)	0.0135 (6)	0.0034 (5)	0.0054 (5)	−0.0033 (4)
O6	0.0381 (8)	0.0110 (6)	0.0205 (6)	0.0021 (5)	0.0089 (5)	0.0003 (5)
N1	0.0170 (7)	0.0130 (6)	0.0130 (6)	0.0002 (5)	0.0033 (5)	0.0006 (5)
N2	0.0174 (7)	0.0133 (7)	0.0129 (6)	0.0001 (5)	0.0024 (5)	0.0007 (5)
C1	0.0143 (7)	0.0117 (7)	0.0167 (8)	−0.0022 (6)	0.0027 (6)	−0.0022 (6)
C2	0.0188 (8)	0.0128 (8)	0.0158 (8)	−0.0016 (6)	0.0029 (6)	−0.0002 (6)
C3	0.0162 (8)	0.0180 (8)	0.0149 (8)	−0.0035 (6)	0.0045 (6)	−0.0033 (6)
C4	0.0178 (8)	0.0137 (8)	0.0200 (8)	−0.0006 (6)	0.0042 (6)	−0.0061 (6)
C5	0.0138 (7)	0.0118 (7)	0.0195 (8)	−0.0010 (6)	0.0020 (6)	−0.0022 (6)
C6	0.0156 (7)	0.0127 (8)	0.0175 (8)	−0.0012 (6)	0.0023 (6)	−0.0025 (6)
C7	0.0154 (8)	0.0103 (7)	0.0178 (8)	0.0005 (6)	0.0012 (6)	−0.0004 (6)
C8	0.0229 (8)	0.0131 (8)	0.0134 (8)	0.0023 (6)	0.0046 (6)	0.0025 (6)
C9	0.0229 (9)	0.0161 (8)	0.0122 (7)	0.0024 (6)	0.0023 (6)	0.0011 (6)
C10	0.0176 (8)	0.0164 (8)	0.0128 (7)	−0.0002 (6)	0.0031 (6)	−0.0025 (6)
C11	0.0173 (8)	0.0127 (8)	0.0166 (8)	−0.0009 (6)	0.0022 (6)	−0.0030 (6)
C12	0.0192 (8)	0.0159 (8)	0.0145 (7)	−0.0010 (6)	0.0028 (6)	−0.0039 (6)
C13	0.0244 (9)	0.0127 (8)	0.0196 (8)	0.0001 (6)	0.0044 (6)	−0.0051 (6)
C14	0.0202 (8)	0.0109 (7)	0.0204 (8)	−0.0006 (6)	0.0027 (6)	0.0006 (6)
C15	0.0213 (8)	0.0131 (8)	0.0154 (7)	−0.0019 (6)	0.0050 (6)	−0.0012 (6)
C16	0.0148 (7)	0.0118 (7)	0.0169 (8)	−0.0026 (6)	0.0037 (6)	−0.0023 (6)
C17	0.0445 (12)	0.0206 (9)	0.0144 (8)	−0.0075 (8)	0.0067 (7)	0.0003 (7)
C18	0.0266 (9)	0.0127 (8)	0.0249 (9)	0.0053 (7)	0.0051 (7)	−0.0042 (6)
C19	0.0239 (9)	0.0187 (8)	0.0186 (8)	0.0024 (7)	0.0061 (6)	−0.0051 (6)
C20	0.0318 (10)	0.0153 (8)	0.0231 (9)	0.0041 (7)	0.0105 (7)	0.0053 (7)

Geometric parameters (Å, º) top

Ni—N1	1.8448 (14)	C8—C9	1.511 (2)
Ni—N2	1.8478 (14)	C8—H8A	0.9900
Ni—O2	1.8520 (12)	C8—H8B	0.9900
Ni—O1	1.8536 (12)	C9—H9A	0.9900
O1—C1	1.310 (2)	C9—H9B	0.9900
O2—C16	1.310 (2)	C10—C11	1.418 (2)
O3—C3	1.356 (2)	C10—H10A	0.9500
O3—C17	1.431 (2)	C11—C16	1.423 (2)
O4—C5	1.361 (2)	C11—C12	1.431 (2)
O4—C18	1.4316 (19)	C12—C13	1.368 (2)
O5—C12	1.369 (2)	C13—C14	1.415 (2)
O5—C19	1.4311 (19)	C13—H13A	0.9500
O6—C14	1.368 (2)	C14—C15	1.373 (2)
O6—C20	1.428 (2)	C15—C16	1.413 (2)
N1—C7	1.295 (2)	C15—H15A	0.9500
N1—C8	1.4705 (19)	C17—H17A	0.9800
N2—C10	1.299 (2)	C17—H17B	0.9800
N2—C9	1.472 (2)	C17—H17C	0.9800
C1—C2	1.418 (2)	C18—H18A	0.9800
C1—C6	1.422 (2)	C18—H18B	0.9800
C2—C3	1.381 (2)	C18—H18C	0.9800
C2—H2A	0.9500	C19—H19A	0.9800
C3—C4	1.406 (2)	C19—H19B	0.9800
C4—C5	1.373 (2)	C19—H19C	0.9800
C4—H4A	0.9500	C20—H20A	0.9800
C5—C6	1.426 (2)	C20—H20B	0.9800
C6—C7	1.426 (2)	C20—H20C	0.9800
C7—H7A	0.9500

N1—Ni—N2	85.95 (6)	N2—C9—H9B	110.5
N1—Ni—O2	177.34 (6)	C8—C9—H9B	110.5
N2—Ni—O2	94.11 (6)	H9A—C9—H9B	108.7
N1—Ni—O1	93.64 (6)	N2—C10—C11	124.68 (15)
N2—Ni—O1	176.89 (6)	N2—C10—H10A	117.7
O2—Ni—O1	86.44 (5)	C11—C10—H10A	117.7
C1—O1—Ni	126.87 (11)	C10—C11—C16	121.80 (15)
C16—O2—Ni	127.42 (10)	C10—C11—C12	119.46 (15)
C3—O3—C17	117.05 (13)	C16—C11—C12	118.73 (15)
C5—O4—C18	116.65 (13)	C13—C12—O5	123.95 (15)
C12—O5—C19	117.32 (13)	C13—C12—C11	121.68 (15)
C14—O6—C20	116.69 (13)	O5—C12—C11	114.37 (14)
C7—N1—C8	119.28 (14)	C12—C13—C14	118.19 (15)
C7—N1—Ni	127.27 (12)	C12—C13—H13A	120.9
C8—N1—Ni	113.45 (10)	C14—C13—H13A	120.9
C10—N2—C9	118.73 (13)	O6—C14—C15	123.75 (15)
C10—N2—Ni	127.03 (12)	O6—C14—C13	113.77 (15)
C9—N2—Ni	114.24 (11)	C15—C14—C13	122.48 (15)
O1—C1—C2	117.36 (14)	C14—C15—C16	119.78 (15)
O1—C1—C6	123.69 (15)	C14—C15—H15A	120.1
C2—C1—C6	118.94 (14)	C16—C15—H15A	120.1
C3—C2—C1	119.91 (15)	O2—C16—C15	117.64 (14)
C3—C2—H2A	120.0	O2—C16—C11	123.25 (15)
C1—C2—H2A	120.0	C15—C16—C11	119.11 (15)
O3—C3—C2	124.24 (16)	O3—C17—H17A	109.5
O3—C3—C4	113.82 (15)	O3—C17—H17B	109.5
C2—C3—C4	121.94 (15)	H17A—C17—H17B	109.5
C5—C4—C3	118.66 (15)	O3—C17—H17C	109.5
C5—C4—H4A	120.7	H17A—C17—H17C	109.5
C3—C4—H4A	120.7	H17B—C17—H17C	109.5
O4—C5—C4	123.50 (15)	O4—C18—H18A	109.5
O4—C5—C6	114.92 (14)	O4—C18—H18B	109.5
C4—C5—C6	121.58 (15)	H18A—C18—H18B	109.5
C1—C6—C7	121.24 (15)	O4—C18—H18C	109.5
C1—C6—C5	118.77 (15)	H18A—C18—H18C	109.5
C7—C6—C5	119.70 (15)	H18B—C18—H18C	109.5
N1—C7—C6	123.96 (15)	O5—C19—H19A	109.5
N1—C7—H7A	118.0	O5—C19—H19B	109.5
C6—C7—H7A	118.0	H19A—C19—H19B	109.5
N1—C8—C9	106.45 (13)	O5—C19—H19C	109.5
N1—C8—H8A	110.4	H19A—C19—H19C	109.5
C9—C8—H8A	110.4	H19B—C19—H19C	109.5
N1—C8—H8B	110.4	O6—C20—H20A	109.5
C9—C8—H8B	110.4	O6—C20—H20B	109.5
H8A—C8—H8B	108.6	H20A—C20—H20B	109.5
N2—C9—C8	106.22 (13)	O6—C20—H20C	109.5
N2—C9—H9A	110.5	H20A—C20—H20C	109.5
C8—C9—H9A	110.5	H20B—C20—H20C	109.5

N1—Ni—O1—C1	−16.22 (14)	O4—C5—C6—C7	−8.9 (2)
N2—Ni—O1—C1	−98.5 (11)	C4—C5—C6—C7	171.01 (15)
O2—Ni—O1—C1	161.12 (14)	C8—N1—C7—C6	171.34 (15)
N1—Ni—O2—C16	−105.1 (12)	Ni—N1—C7—C6	−8.6 (2)
N2—Ni—O2—C16	−13.82 (14)	C1—C6—C7—N1	−8.2 (3)
O1—Ni—O2—C16	163.11 (14)	C5—C6—C7—N1	177.99 (16)
N2—Ni—N1—C7	−165.37 (15)	C7—N1—C8—C9	146.29 (15)
O2—Ni—N1—C7	−73.9 (12)	Ni—N1—C8—C9	−33.74 (16)
O1—Ni—N1—C7	17.72 (15)	C10—N2—C9—C8	151.31 (15)
N2—Ni—N1—C8	14.66 (12)	Ni—N2—C9—C8	−29.43 (16)
O2—Ni—N1—C8	106.1 (12)	N1—C8—C9—N2	38.49 (17)
O1—Ni—N1—C8	−162.25 (11)	C9—N2—C10—C11	175.76 (15)
N1—Ni—N2—C10	−171.54 (15)	Ni—N2—C10—C11	−3.4 (3)
O2—Ni—N2—C10	11.12 (15)	N2—C10—C11—C16	−6.4 (3)
O1—Ni—N2—C10	−89.0 (11)	N2—C10—C11—C12	175.06 (16)
N1—Ni—N2—C9	9.28 (12)	C19—O5—C12—C13	14.1 (2)
O2—Ni—N2—C9	−168.06 (11)	C19—O5—C12—C11	−165.63 (15)
O1—Ni—N2—C9	91.8 (11)	C10—C11—C12—C13	177.11 (16)
Ni—O1—C1—C2	−175.30 (11)	C16—C11—C12—C13	−1.5 (3)
Ni—O1—C1—C6	5.7 (2)	C10—C11—C12—O5	−3.2 (2)
O1—C1—C2—C3	178.92 (15)	C16—C11—C12—O5	178.18 (14)
C6—C1—C2—C3	−2.0 (2)	O5—C12—C13—C14	−179.25 (16)
C17—O3—C3—C2	5.6 (2)	C11—C12—C13—C14	0.4 (3)
C17—O3—C3—C4	−173.47 (16)	C20—O6—C14—C15	−0.1 (3)
C1—C2—C3—O3	178.78 (15)	C20—O6—C14—C13	−179.51 (15)
C1—C2—C3—C4	−2.2 (3)	C12—C13—C14—O6	−179.43 (16)
O3—C3—C4—C5	−177.02 (15)	C12—C13—C14—C15	1.1 (3)
C2—C3—C4—C5	3.9 (2)	O6—C14—C15—C16	179.13 (16)
C18—O4—C5—C4	−1.1 (2)	C13—C14—C15—C16	−1.5 (3)
C18—O4—C5—C6	178.73 (14)	Ni—O2—C16—C15	−170.27 (11)
C3—C4—C5—O4	178.62 (15)	Ni—O2—C16—C11	8.7 (2)
C3—C4—C5—C6	−1.2 (2)	C14—C15—C16—O2	179.34 (15)
O1—C1—C6—C7	9.7 (3)	C14—C15—C16—C11	0.3 (2)
C2—C1—C6—C7	−169.32 (15)	C10—C11—C16—O2	3.6 (3)
O1—C1—C6—C5	−176.52 (15)	C12—C11—C16—O2	−177.85 (15)
C2—C1—C6—C5	4.5 (2)	C10—C11—C16—C15	−177.45 (15)
O4—C5—C6—C1	177.22 (14)	C12—C11—C16—C15	1.1 (2)
C4—C5—C6—C1	−2.9 (2)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C8—H8B···O2ⁱ	0.99	2.61	3.587 (2)	169
C17—H17A···O4ⁱⁱ	0.98	2.60	3.484 (2)	150

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

Experimental details

Crystal data
Chemical formula	[Ni(C₂₀H₂₂N₂O₆)]
M_r	445.11
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	110
a, b, c (Å)	7.41599 (12), 15.6945 (2), 15.7203 (2)
β (°)	91.9153 (13)
V (Å³)	1828.67 (5)
Z	4
Radiation type	Cu Kα
µ (mm⁻¹)	1.91
Crystal size (mm)	0.53 × 0.15 × 0.12

Data collection
Diffractometer	Oxford Diffraction Xcalibur Ruby Gemini
Absorption correction	Multi-scan (CrysAlis PRO; Oxford Diffraction, 2007)
T_min, T_max	0.602, 1.000
No. of measured, independent and observed [I > 2σ(I)] reflections	6746, 3603, 3370
R_int	0.022
(sin θ/λ)_max (Å⁻¹)	0.624

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.036, 0.098, 1.04
No. of reflections	3603
No. of parameters	266
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.42, −0.47

Computer programs: CrysAlis PRO (Oxford Diffraction, 2007), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).