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Acta Crystallogr Sect E Struct Rep Online. 2009 July 1; 65(Pt 7): m703.
Published online 2009 June 6. doi:  10.1107/S1600536809019965
PMCID: PMC2969458

{4,4′-Dimeth­oxy-2,2′-[2,2-dimethyl­propane-1,3-diylbis(nitrilo­methyl­idyne)]diphenolato}nickel(II)

Abstract

In the title complex, [Ni(C21H24N2O4)], the NiII ion has a slightly distorted square-planar geometry, coordinated by the two N and two O atoms of a new tetra­dentate Schiff base ligand. The dihedral angle between the planes of the two NiNC3O chelate rings is 14.37 (12)°.

Related literature

For the structures of free Schiff bases, see: Garnovskii et al. (1993 [triangle]). Nickel(II) complexes with N2O2 Schiff-base ligands derived from salicylaldehyde have long been used as homogenous catalysts (Gosden et al., 1981 [triangle]; Healy & Pletcher, 1978 [triangle]). For related structures, see: Habibi et al. (2007a [triangle],b [triangle]). For Ni—O and Ni—N distances, see: Akhtar (1981 [triangle]); Shkolnikova et al. (1970 [triangle]).

An external file that holds a picture, illustration, etc.
Object name is e-65-0m703-scheme1.jpg

Experimental

Crystal data

  • [Ni(C21H24N2O4)]
  • M r = 427.13
  • Orthorhombic, An external file that holds a picture, illustration, etc.
Object name is e-65-0m703-efi1.jpg
  • a = 15.6110 (7) Å
  • b = 9.1151 (5) Å
  • c = 26.8142 (12) Å
  • V = 3815.5 (3) Å3
  • Z = 8
  • Mo Kα radiation
  • μ = 1.05 mm−1
  • T = 193 K
  • 0.30 × 0.20 × 0.20 mm

Data collection

  • Rigaku R-AXIS RAPID diffractometer
  • Absorption correction: multi-scan (ABSCOR; Higashi, 1995 [triangle]) T min = 0.744, T max = 0.818
  • 35644 measured reflections
  • 4362 independent reflections
  • 3946 reflections with I > 2σ(I)
  • R int = 0.020

Refinement

  • R[F 2 > 2σ(F 2)] = 0.026
  • wR(F 2) = 0.071
  • S = 1.05
  • 4362 reflections
  • 258 parameters
  • H-atom parameters constrained
  • Δρmax = 0.43 e Å−3
  • Δρmin = −0.18 e Å−3

Data collection: PROCESS-AUTO (Rigaku, 1998 [triangle]); cell refinement: PROCESS-AUTO; data reduction: CrystalStructure (Rigaku/MSC, 2004 [triangle]); program(s) used to solve structure: SIR2004 (Burla et al., 2005 [triangle]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 [triangle]); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997 [triangle]); software used to prepare material for publication: SHELXL97.

Supplementary Material

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536809019965/bt2968sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536809019965/bt2968Isup2.hkl

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

Acknowledgments

We thank Yasouj University and the University of Isfahan for partial support of this work.

supplementary crystallographic information

Comment

Schiff bases and their biologically active complexes have been studied extensively over the past decade. Although numerous transition metal complexes of Schiff bases have been structurally characterized, relatively few free Schiff bases have been similarly characterized (Garnovskii et al., 1993).

Nickel(II) complexes with N2O2 Schiff-base ligands derived from salicylaldehyde have long been used as homogenous catalysts (Gosden et al., 1981; Healy & Pletcher, 1978).

Recently we reported the structure of a copper(II) and nickel(II) complexes with the N,N'-bis(6-methoxysalicylidene)-1,3-diaminopropane ligand (Habibi et al., 2007a,b). The title compound is isostructural with its CuII and NiII analogues.

In the title compound (Figure 1), the Ni—O and Ni—N distances are larger than the comparable mean distances of 1.829 and 1.859 Å (Table 1), respectively, in N,N'-ethylenebis(salicylideneiminato)nickel(II) (Shkolnikova et al., 1970) and 1.849 (2) and 1.840 (2) Å, respectively, in N,N'-ethylenebis[(2-hydroxy-1-naphthyl)methaniminato]nickel(II) (Akhtar, 1981).

Experimental

A mixture of 6-methoxysalicylaldehyde (2.0 mmol, 304 mg) and 2,2-dimethylpropane-1,3-diamine (1.0 mmol, 102 mg) was dissolved in methanol (10 ml) with stirring for 15 min at room temperature, to give a clear yellow solution. A methanol solution (10 ml) of Ni(OAc)2.4H2O (1.0 mmol, 249 mg) was then added. The mixture was refluxed for a further 45 min and then filtered. After keeping the filtrate in air for 5 d, dark green block-shaped crystals were formed at the bottom of the vessel on slow evaporation of the solvent, in about 85% yield.

Refinement

All H atoms were placed in geometrically idealized positions and allowed to ride on their parent atoms, with C—H distances in the range 0.93–0.97 Å and with Uiso(H) = 1.2 or 1.5 times Ueq(C).

Figures

Fig. 1.
A view of the title compound, showing the atom-numbering scheme. Displacement ellipsoids are drawn at the 30% probability level and H atoms are shown as small spheres of arbitrary radii.

Crystal data

[Ni(C21H24N2O4)]Dx = 1.487 Mg m3
Mr = 427.13Mo Kα radiation, λ = 0.71075 Å
Orthorhombic, PbcaCell parameters from 27241 reflections
a = 15.6110 (7) Åθ = 3.0–27.5°
b = 9.1151 (5) ŵ = 1.05 mm1
c = 26.8142 (12) ÅT = 193 K
V = 3815.5 (3) Å3Block, dark-green
Z = 80.30 × 0.20 × 0.20 mm
F(000) = 1792

Data collection

Rigaku R-AXIS RAPID diffractometer4362 independent reflections
Radiation source: fine-focus sealed tube3946 reflections with I > 2σ(I)
graphiteRint = 0.020
Detector resolution: 10.00 pixels mm-1θmax = 27.5°, θmin = 3.0°
ω scansh = −20→20
Absorption correction: multi-scan (ABSCOR; Higashi, 1995)k = −11→11
Tmin = 0.744, Tmax = 0.818l = −34→32
35644 measured reflections

Refinement

Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.026Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.071H-atom parameters constrained
S = 1.05w = 1/[σ2(Fo2) + (0.0413P)2 + 1.3733P] where P = (Fo2 + 2Fc2)/3
4362 reflections(Δ/σ)max = 0.001
258 parametersΔρmax = 0.43 e Å3
0 restraintsΔρmin = −0.18 e Å3

Special details

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)

xyzUiso*/Ueq
Ni10.951753 (10)0.180679 (18)0.014687 (6)0.02025 (7)
O10.85263 (6)0.10007 (11)0.04139 (3)0.0281 (2)
O20.91005 (6)0.10714 (11)−0.04479 (3)0.0271 (2)
O30.75989 (7)0.00704 (12)0.23785 (4)0.0353 (2)
O41.01038 (8)0.20756 (14)−0.23918 (4)0.0398 (3)
N10.97892 (7)0.27883 (12)0.07416 (4)0.0215 (2)
N21.05801 (7)0.23220 (13)−0.01347 (4)0.0209 (2)
C10.83516 (8)0.08183 (15)0.08876 (5)0.0234 (3)
C20.76375 (9)−0.00620 (16)0.10235 (5)0.0287 (3)
H20.7304−0.05120.07700.034*
C30.74193 (9)−0.02755 (16)0.15133 (5)0.0304 (3)
H30.6940−0.08740.15920.036*
C40.78912 (9)0.03727 (15)0.19010 (5)0.0273 (3)
C50.85834 (8)0.12301 (15)0.17879 (5)0.0252 (3)
H50.89080.16690.20480.030*
C60.88167 (8)0.14645 (14)0.12825 (5)0.0227 (3)
C70.94728 (8)0.25124 (15)0.11773 (5)0.0229 (3)
H70.96960.30530.14510.028*
C80.79861 (12)0.0897 (2)0.27678 (6)0.0436 (4)
H8A0.76920.06930.30830.052*
H8B0.79420.19460.26910.052*
H8C0.85910.06230.27970.052*
C91.03568 (8)0.40646 (14)0.06956 (5)0.0231 (3)
H9A1.03360.46350.10090.028*
H9B1.01440.47040.04240.028*
C101.12843 (8)0.36428 (15)0.05867 (5)0.0238 (3)
C110.93847 (8)0.13593 (15)−0.08973 (5)0.0232 (3)
C120.88895 (9)0.08927 (15)−0.13120 (5)0.0272 (3)
H120.83680.0382−0.12550.033*
C130.91455 (9)0.11618 (16)−0.17925 (5)0.0290 (3)
H130.87940.0852−0.20620.035*
C140.99180 (10)0.18878 (15)−0.18915 (5)0.0289 (3)
C151.04265 (9)0.23295 (16)−0.15007 (5)0.0272 (3)
H151.09560.2807−0.15650.033*
C161.01630 (9)0.20742 (14)−0.10023 (5)0.0228 (3)
C171.07511 (8)0.23987 (14)−0.06053 (5)0.0226 (2)
H171.13130.2695−0.06970.027*
C181.08696 (13)0.2857 (2)−0.24969 (6)0.0474 (4)
H18A1.09400.2950−0.28590.057*
H18B1.13600.2325−0.23570.057*
H18C1.08380.3836−0.23470.057*
C191.13172 (8)0.23648 (15)0.02101 (5)0.0230 (3)
H19A1.18510.24460.00120.028*
H19B1.13410.14280.03960.028*
C201.17187 (10)0.31209 (18)0.10659 (6)0.0349 (3)
H20A1.22950.27610.09880.042*
H20B1.13810.23280.12150.042*
H20C1.17590.39400.13020.042*
C211.17386 (10)0.49902 (17)0.03763 (6)0.0364 (3)
H21A1.23480.47690.03290.044*
H21B1.16780.58110.06100.044*
H21C1.14820.52560.00550.044*

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
Ni10.01948 (10)0.02097 (10)0.02030 (10)−0.00186 (6)0.00049 (6)−0.00188 (6)
O10.0253 (5)0.0358 (5)0.0231 (4)−0.0077 (4)0.0010 (4)−0.0026 (4)
O20.0279 (5)0.0305 (5)0.0229 (4)−0.0065 (4)0.0015 (4)−0.0025 (4)
O30.0381 (6)0.0421 (6)0.0258 (5)−0.0117 (5)0.0024 (5)0.0073 (4)
O40.0459 (7)0.0524 (7)0.0211 (5)−0.0077 (5)−0.0003 (5)0.0034 (4)
N10.0194 (5)0.0200 (5)0.0250 (5)−0.0007 (4)0.0011 (4)−0.0019 (4)
N20.0207 (5)0.0189 (5)0.0230 (5)0.0012 (4)−0.0007 (4)−0.0017 (4)
C10.0212 (6)0.0239 (6)0.0253 (6)0.0006 (5)0.0014 (5)−0.0005 (5)
C20.0258 (7)0.0303 (7)0.0302 (7)−0.0059 (5)−0.0019 (6)−0.0016 (5)
C30.0267 (7)0.0312 (7)0.0332 (7)−0.0076 (5)0.0014 (6)0.0037 (6)
C40.0290 (7)0.0281 (7)0.0248 (6)−0.0009 (5)0.0019 (5)0.0047 (5)
C50.0245 (6)0.0275 (7)0.0236 (6)−0.0004 (5)−0.0014 (5)0.0009 (5)
C60.0209 (6)0.0223 (6)0.0248 (6)0.0005 (5)0.0010 (5)−0.0006 (5)
C70.0217 (6)0.0235 (7)0.0236 (6)0.0005 (5)−0.0012 (5)−0.0031 (5)
C80.0474 (9)0.0601 (11)0.0234 (7)−0.0133 (8)−0.0003 (7)0.0057 (7)
C90.0246 (6)0.0191 (6)0.0255 (6)−0.0018 (5)0.0024 (5)−0.0028 (5)
C100.0213 (6)0.0239 (6)0.0262 (6)−0.0031 (5)0.0005 (5)−0.0032 (5)
C110.0256 (6)0.0198 (6)0.0242 (6)0.0024 (5)0.0003 (5)−0.0024 (5)
C120.0257 (6)0.0267 (7)0.0292 (7)−0.0003 (5)−0.0016 (5)−0.0041 (5)
C130.0321 (7)0.0295 (7)0.0254 (6)0.0030 (6)−0.0053 (6)−0.0042 (5)
C140.0356 (8)0.0293 (7)0.0219 (6)0.0026 (6)0.0003 (6)0.0011 (5)
C150.0291 (7)0.0263 (7)0.0262 (7)−0.0006 (5)0.0019 (5)0.0007 (5)
C160.0256 (6)0.0200 (6)0.0230 (6)0.0016 (5)−0.0004 (5)−0.0018 (5)
C170.0226 (6)0.0196 (6)0.0257 (6)−0.0004 (5)0.0019 (5)−0.0018 (5)
C180.0581 (11)0.0578 (11)0.0264 (7)−0.0113 (9)0.0073 (8)0.0074 (7)
C190.0190 (6)0.0244 (6)0.0256 (6)0.0011 (5)−0.0022 (5)−0.0024 (5)
C200.0314 (7)0.0428 (9)0.0304 (7)0.0021 (6)−0.0072 (6)−0.0077 (6)
C210.0331 (8)0.0281 (7)0.0480 (9)−0.0089 (6)0.0117 (7)−0.0044 (6)

Geometric parameters (Å, °)

Ni1—O21.8483 (9)C9—C101.5264 (17)
Ni1—O11.8566 (9)C9—H9A0.9900
Ni1—N11.8770 (11)C9—H9B0.9900
Ni1—N21.8821 (11)C10—C211.5263 (19)
O1—C11.3098 (16)C10—C201.529 (2)
O2—C111.3107 (16)C10—C191.5425 (18)
O3—C41.3869 (16)C11—C161.4072 (18)
O3—C81.4222 (19)C11—C121.4196 (19)
O4—C141.3833 (17)C12—C131.3710 (19)
O4—C181.420 (2)C12—H120.9500
N1—C71.2932 (17)C13—C141.401 (2)
N1—C91.4676 (16)C13—H130.9500
N2—C171.2917 (17)C14—C151.375 (2)
N2—C191.4765 (16)C15—C161.4174 (19)
C1—C61.4124 (18)C15—H150.9500
C1—C21.4211 (18)C16—C171.4368 (18)
C2—C31.371 (2)C17—H170.9500
C2—H20.9500C18—H18A0.9800
C3—C41.404 (2)C18—H18B0.9800
C3—H30.9500C18—H18C0.9800
C4—C51.3678 (19)C19—H19A0.9900
C5—C61.4195 (18)C19—H19B0.9900
C5—H50.9500C20—H20A0.9800
C6—C71.4286 (18)C20—H20B0.9800
C7—H70.9500C20—H20C0.9800
C8—H8A0.9800C21—H21A0.9800
C8—H8B0.9800C21—H21B0.9800
C8—H8C0.9800C21—H21C0.9800
O2—Ni1—O184.02 (4)C21—C10—C20110.79 (12)
O2—Ni1—N1170.21 (5)C9—C10—C20109.78 (11)
O1—Ni1—N192.82 (4)C21—C10—C19110.51 (11)
O2—Ni1—N293.14 (4)C9—C10—C19110.31 (10)
O1—Ni1—N2171.13 (5)C20—C10—C19107.48 (11)
N1—Ni1—N291.30 (5)O2—C11—C16124.67 (12)
C1—O1—Ni1126.72 (8)O2—C11—C12118.43 (12)
C11—O2—Ni1126.98 (9)C16—C11—C12116.88 (12)
C4—O3—C8115.62 (11)C13—C12—C11121.59 (13)
C14—O4—C18115.53 (12)C13—C12—H12119.2
C7—N1—C9117.43 (11)C11—C12—H12119.2
C7—N1—Ni1126.06 (9)C12—C13—C14120.89 (13)
C9—N1—Ni1116.29 (8)C12—C13—H13119.6
C17—N2—C19116.69 (11)C14—C13—H13119.6
C17—N2—Ni1125.98 (9)C15—C14—O4125.58 (14)
C19—N2—Ni1116.25 (8)C15—C14—C13119.40 (13)
O1—C1—C6124.53 (12)O4—C14—C13115.01 (13)
O1—C1—C2118.93 (12)C14—C15—C16120.19 (13)
C6—C1—C2116.53 (12)C14—C15—H15119.9
C3—C2—C1121.38 (13)C16—C15—H15119.9
C3—C2—H2119.3C11—C16—C15121.02 (12)
C1—C2—H2119.3C11—C16—C17119.92 (12)
C2—C3—C4121.28 (13)C15—C16—C17118.64 (12)
C2—C3—H3119.4N2—C17—C16125.50 (12)
C4—C3—H3119.4N2—C17—H17117.2
C5—C4—O3125.32 (13)C16—C17—H17117.2
C5—C4—C3119.38 (13)O4—C18—H18A109.5
O3—C4—C3115.30 (12)O4—C18—H18B109.5
C4—C5—C6120.03 (12)H18A—C18—H18B109.5
C4—C5—H5120.0O4—C18—H18C109.5
C6—C5—H5120.0H18A—C18—H18C109.5
C1—C6—C5121.40 (12)H18B—C18—H18C109.5
C1—C6—C7119.97 (12)N2—C19—C10113.82 (11)
C5—C6—C7118.23 (12)N2—C19—H19A108.8
N1—C7—C6125.60 (12)C10—C19—H19A108.8
N1—C7—H7117.2N2—C19—H19B108.8
C6—C7—H7117.2C10—C19—H19B108.8
O3—C8—H8A109.5H19A—C19—H19B107.7
O3—C8—H8B109.5C10—C20—H20A109.5
H8A—C8—H8B109.5C10—C20—H20B109.5
O3—C8—H8C109.5H20A—C20—H20B109.5
H8A—C8—H8C109.5C10—C20—H20C109.5
H8B—C8—H8C109.5H20A—C20—H20C109.5
N1—C9—C10112.90 (10)H20B—C20—H20C109.5
N1—C9—H9A109.0C10—C21—H21A109.5
C10—C9—H9A109.0C10—C21—H21B109.5
N1—C9—H9B109.0H21A—C21—H21B109.5
C10—C9—H9B109.0C10—C21—H21C109.5
H9A—C9—H9B107.8H21A—C21—H21C109.5
C21—C10—C9107.99 (11)H21B—C21—H21C109.5
O2—Ni1—O1—C1167.96 (12)C9—N1—C7—C6170.27 (12)
N1—Ni1—O1—C1−21.33 (12)Ni1—N1—C7—C6−4.06 (19)
N2—Ni1—O1—C196.3 (3)C1—C6—C7—N1−11.4 (2)
O1—Ni1—O2—C11168.52 (11)C5—C6—C7—N1175.86 (13)
N1—Ni1—O2—C1197.0 (3)C7—N1—C9—C10112.05 (13)
N2—Ni1—O2—C11−19.91 (11)Ni1—N1—C9—C10−73.06 (12)
O2—Ni1—N1—C787.7 (3)N1—C9—C10—C21161.18 (11)
O1—Ni1—N1—C716.86 (11)N1—C9—C10—C20−77.94 (14)
N2—Ni1—N1—C7−155.28 (11)N1—C9—C10—C1940.32 (15)
O2—Ni1—N1—C9−86.7 (3)Ni1—O2—C11—C1612.44 (19)
O1—Ni1—N1—C9−157.53 (9)Ni1—O2—C11—C12−169.17 (9)
N2—Ni1—N1—C930.33 (9)O2—C11—C12—C13179.71 (13)
O2—Ni1—N2—C1714.38 (12)C16—C11—C12—C13−1.8 (2)
O1—Ni1—N2—C1785.4 (3)C11—C12—C13—C141.2 (2)
N1—Ni1—N2—C17−156.90 (12)C18—O4—C14—C15−3.2 (2)
O2—Ni1—N2—C19−153.30 (9)C18—O4—C14—C13177.78 (14)
O1—Ni1—N2—C19−82.3 (3)C12—C13—C14—C150.3 (2)
N1—Ni1—N2—C1935.43 (9)C12—C13—C14—O4179.37 (13)
Ni1—O1—C1—C613.03 (19)O4—C14—C15—C16179.91 (13)
Ni1—O1—C1—C2−168.29 (10)C13—C14—C15—C16−1.1 (2)
O1—C1—C2—C3−179.21 (13)O2—C11—C16—C15179.35 (13)
C6—C1—C2—C3−0.4 (2)C12—C11—C16—C150.93 (19)
C1—C2—C3—C40.3 (2)O2—C11—C16—C176.8 (2)
C8—O3—C4—C59.4 (2)C12—C11—C16—C17−171.57 (12)
C8—O3—C4—C3−170.61 (14)C14—C15—C16—C110.5 (2)
C2—C3—C4—C5−0.2 (2)C14—C15—C16—C17173.07 (13)
C2—C3—C4—O3179.77 (14)C19—N2—C17—C16166.28 (12)
O3—C4—C5—C6−179.65 (13)Ni1—N2—C17—C16−1.35 (19)
C3—C4—C5—C60.3 (2)C11—C16—C17—N2−12.5 (2)
O1—C1—C6—C5179.26 (13)C15—C16—C17—N2174.77 (13)
C2—C1—C6—C50.56 (19)C17—N2—C19—C10121.25 (13)
O1—C1—C6—C76.7 (2)Ni1—N2—C19—C10−69.89 (13)
C2—C1—C6—C7−171.96 (12)C21—C10—C19—N2−90.70 (14)
C4—C5—C6—C1−0.5 (2)C9—C10—C19—N228.64 (15)
C4—C5—C6—C7172.12 (12)C20—C10—C19—N2148.30 (11)

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: BT2968).

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