Bis{2-meth­oxy-6-[3-(methyl­amino)­propyl­imino­meth­yl]phenolato}nickel(II)

The title complex, [Ni(C₁₂H₁₇N₂O₂)₂], possesses a crystallographically imposed center of symmetry occupied by the Ni^II ion. Each 2-meth­oxy-6-[3-(methyl­amino)propyl­imino­meth­yl]­phenolate ligand coordinates the Ni atom in a tridentate mode [Ni-O = 2.0356 (18) Å, and Ni-N = 2.048 (2) and 2.184 (2) Å], resulting in a distorted octa­hedral coordination geometry.

Key indicators

• Single-crystal X-ray study
• T = 298 K
• Mean [sigma](C-C) = 0.004 Å
• R factor = 0.035
• wR factor = 0.095
• Data-to-parameter ratio = 13.7

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT125_ALERT_4_C No _symmetry_space_group_name_Hall Given .......          ?
PLAT222_ALERT_3_C Large Non-Solvent    H     Ueq(max)/Ueq(min) ...       3.77 Ratio
PLAT245_ALERT_2_C U(iso) H2      Smaller than U(eq) N2      by ...       0.01 AngSq
PLAT420_ALERT_2_C D-H Without Acceptor       N2     -   H2     ...          ?

Alert level G
PLAT793_ALERT_1_G Check the Absolute Configuration of N2     = ...          S
PLAT860_ALERT_3_G Note: Number of Least-Squares Restraints .......          1

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

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

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S1. Comment

In continuation of our study of Ni complexes with Shiff base ligands (Tang, 2006), we report here the crystal structure of the title compound, NiL₂, where HL is a Shiff base 2-methoxy-6-[(3-methylaminopropylimino)methyl]phenol.

The title complex [Ni(C₁₂H₁₇N₂O₂)₂] is a centrosymmetric mononuclear nickel(II) complex (Fig. 1). The Ni atom, lying on the inversion centre, is six-coordinated by two phenolic oxygen atoms, two imine N atoms and two amine N atoms from two Schiff base ligands, forming an octahedral coordination geometry. The coordinative bond lengths and angles are within normal ranges and comparable with those observed in similar nickel(II) complexes (Zhu et al., 2004; Liu et al., 2006; Zhang, 2006; Diao, 2007; Diao, Li et al., 2007).

Related literature

For related crystal structures, see: Zhu et al. (2004); Liu et al. (2006); Zhang (2006); Tang (2006); Diao (2007); Diao et al. (2007).

S2. Experimental

3-Methoxy-2-hydroxybenzaldehyde (0.2 mmol, 30.5 mg) and N-methyl-1,3-diaminopropane (0.2 mmol, 17.6 mg) were dissolved in a methanol solution (10 ml). To the mixture was added an aqueous solution (1 ml) of nickel(II) chloride hexahydrate (0.1 mmol, 23.8 mg). The final mixture was stirred at room temperature for 30 min, resulting in a green solution. The solution was allowed to stand in air for three days, yielding green block-shaped crystals of the title complex.

S3. Refinement

H2 attached to N2 was located from a difference Fourier map and refined isotropically, with N–H distance restrained to 0.90 (1) Å. C-bound H atoms were geometrically positioned, with C–H = 0.93–0.97 Å, and refined as riding, with U_iso(H) set to 1.2U_eq(C) or 1.5U_eq(methyl C).

Computing details

Data collection: SMART (Bruker, 2002); cell refinement: SAINT (Bruker, 2002); data reduction: SAINT (Bruker, 2002); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997a); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997a); molecular graphics: SHELXTL (Sheldrick, 1997b); software used to prepare material for publication: SHELXTL (Sheldrick, 1997b).

Figures

Fig. 1. The structure of (I), showing the atom-numbering scheme. Displacement ellipsoids are drawn at the 30% probability level. Unlabelled atoms are related with the labelled ones by symmetry code (-x, 1 - y, 1 - z).

Bis{2-methoxy-6-[3-(methylamino)propyliminomethyl]phenolato}nickel(II)

Crystal data

[Ni(C12H17N2O2)2]	Dx = 1.440 Mg m^−3
Mr = 501.26	Mo Kα radiation, λ = 0.71073 Å
Orthorhombic, Pbca	Cell parameters from 1621 reflections
a = 8.762 (3) Å	θ = 2.3–24.5°
b = 15.297 (5) Å	µ = 0.88 mm^−1
c = 17.247 (5) Å	T = 298 K
V = 2311.5 (12) Å^3	Block, green
Z = 4	0.23 × 0.21 × 0.18 mm
F(000) = 1064

Data collection

Bruker SMART CCD area-detector diffractometer	2150 independent reflections
Radiation source: fine-focus sealed tube	1361 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.058
ω scans	θmax = 25.5°, θmin = 2.4°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	h = −10→8
Tmin = 0.824, Tmax = 0.858	k = −16→18
11114 measured reflections	l = −20→20

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.035	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.095	H atoms treated by a mixture of independent and constrained refinement
S = 1.02	w = 1/[σ^2(Fo^2) + (0.0401P)^2 + 0.8022P] where P = (Fo^2 + 2Fc^2)/3
2150 reflections	(Δ/σ)max < 0.001
157 parameters	Δρmax = 0.27 e Å^−3
1 restraint	Δρmin = −0.33 e Å^−3

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 (Ų)

	x	y	z	Uiso*/Ueq
Ni1	0.0000	0.5000	0.5000	0.02728 (16)
O1	0.1095 (2)	0.46563 (12)	0.40048 (10)	0.0328 (5)
O2	0.2997 (2)	0.38059 (13)	0.30828 (12)	0.0461 (6)
N1	0.0197 (3)	0.62692 (15)	0.46346 (14)	0.0321 (6)
N2	−0.2128 (3)	0.50609 (15)	0.43420 (14)	0.0345 (6)
C1	0.2275 (3)	0.60365 (18)	0.37150 (15)	0.0305 (7)
C2	0.2130 (3)	0.51145 (18)	0.36524 (15)	0.0289 (6)
C3	0.3187 (3)	0.46964 (19)	0.31390 (16)	0.0332 (7)
C4	0.4273 (4)	0.5157 (2)	0.27416 (16)	0.0416 (8)
H4	0.4941	0.4863	0.2413	0.050*
C5	0.4391 (4)	0.6059 (2)	0.28230 (18)	0.0452 (8)
H5	0.5142	0.6366	0.2555	0.054*
C6	0.3404 (3)	0.6492 (2)	0.32953 (16)	0.0394 (8)
H6	0.3474	0.7096	0.3342	0.047*
C7	0.1176 (3)	0.65523 (19)	0.41434 (16)	0.0345 (7)
H7	0.1180	0.7152	0.4052	0.041*
C8	−0.1012 (3)	0.6874 (2)	0.48796 (17)	0.0419 (8)
H8A	−0.0690	0.7473	0.4792	0.050*
H8B	−0.1214	0.6802	0.5429	0.050*
C9	−0.2454 (3)	0.6683 (2)	0.44154 (19)	0.0470 (8)
H9A	−0.3209	0.7126	0.4538	0.056*
H9B	−0.2216	0.6736	0.3868	0.056*
C10	−0.3154 (3)	0.5793 (2)	0.45555 (18)	0.0413 (8)
H10A	−0.3419	0.5742	0.5100	0.050*
H10B	−0.4089	0.5746	0.4257	0.050*
C11	−0.2999 (4)	0.4240 (2)	0.42889 (19)	0.0492 (9)
H11A	−0.3447	0.4110	0.4784	0.074*
H11B	−0.2328	0.3773	0.4140	0.074*
H11C	−0.3791	0.4302	0.3908	0.074*
C12	0.3999 (4)	0.3351 (2)	0.25727 (19)	0.0553 (9)
H12A	0.3926	0.3598	0.2062	0.083*
H12B	0.3718	0.2745	0.2555	0.083*
H12C	0.5028	0.3404	0.2757	0.083*
H2	−0.174 (3)	0.5177 (15)	0.3878 (8)	0.022 (7)*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Ni1	0.0236 (3)	0.0302 (3)	0.0281 (3)	0.0015 (2)	0.0041 (2)	−0.0008 (2)
O1	0.0306 (11)	0.0354 (11)	0.0325 (11)	−0.0025 (9)	0.0083 (10)	−0.0001 (9)
O2	0.0472 (14)	0.0403 (13)	0.0508 (13)	0.0030 (10)	0.0197 (11)	−0.0089 (11)
N1	0.0326 (15)	0.0325 (13)	0.0314 (12)	0.0035 (11)	0.0053 (12)	−0.0016 (11)
N2	0.0309 (14)	0.0408 (14)	0.0318 (13)	−0.0003 (12)	0.0030 (12)	−0.0002 (12)
C1	0.0284 (16)	0.0387 (17)	0.0244 (14)	−0.0011 (13)	−0.0005 (13)	0.0024 (13)
C2	0.0241 (15)	0.0426 (18)	0.0201 (13)	0.0000 (14)	−0.0029 (12)	0.0025 (12)
C3	0.0324 (17)	0.0400 (17)	0.0271 (15)	0.0022 (14)	0.0011 (14)	−0.0014 (13)
C4	0.0363 (18)	0.058 (2)	0.0307 (16)	0.0054 (16)	0.0105 (15)	0.0014 (15)
C5	0.041 (2)	0.051 (2)	0.0430 (18)	−0.0102 (17)	0.0111 (16)	0.0094 (16)
C6	0.0387 (18)	0.0422 (18)	0.0372 (17)	−0.0031 (15)	0.0054 (15)	0.0069 (15)
C7	0.0384 (18)	0.0318 (16)	0.0332 (15)	0.0019 (14)	−0.0047 (15)	0.0018 (13)
C8	0.043 (2)	0.0331 (17)	0.0495 (19)	0.0055 (15)	0.0078 (17)	−0.0031 (14)
C9	0.0404 (19)	0.046 (2)	0.055 (2)	0.0172 (16)	0.0023 (17)	0.0016 (17)
C10	0.0263 (17)	0.055 (2)	0.0428 (18)	0.0085 (15)	−0.0007 (15)	0.0007 (16)
C11	0.045 (2)	0.052 (2)	0.051 (2)	−0.0074 (17)	−0.0110 (17)	−0.0031 (16)
C12	0.063 (2)	0.052 (2)	0.052 (2)	0.0125 (18)	0.019 (2)	−0.0094 (17)

Geometric parameters (Å, º)

Ni1—O1^i	2.0356 (18)	C4—H4	0.9300
Ni1—O1	2.0356 (18)	C5—C6	1.360 (4)
Ni1—N1	2.048 (2)	C5—H5	0.9300
Ni1—N1^i	2.048 (2)	C6—H6	0.9300
Ni1—N2^i	2.184 (2)	C7—H7	0.9300
Ni1—N2	2.184 (2)	C8—C9	1.524 (4)
O1—C2	1.297 (3)	C8—H8A	0.9700
O2—C3	1.376 (3)	C8—H8B	0.9700
O2—C12	1.424 (3)	C9—C10	1.513 (4)
N1—C7	1.281 (3)	C9—H9A	0.9700
N1—C8	1.469 (3)	C9—H9B	0.9700
N2—C11	1.473 (4)	C10—H10A	0.9700
N2—C10	1.483 (4)	C10—H10B	0.9700
N2—H2	0.886 (10)	C11—H11A	0.9600
C1—C6	1.410 (4)	C11—H11B	0.9600
C1—C2	1.420 (4)	C11—H11C	0.9600
C1—C7	1.448 (4)	C12—H12A	0.9600
C2—C3	1.432 (4)	C12—H12B	0.9600
C3—C4	1.368 (4)	C12—H12C	0.9600
C4—C5	1.392 (4)
O1^i—Ni1—O1	180.0	C6—C5—H5	120.1
O1^i—Ni1—N1	93.12 (8)	C4—C5—H5	120.1
O1—Ni1—N1	86.88 (8)	C5—C6—C1	120.9 (3)
O1^i—Ni1—N1^i	86.88 (8)	C5—C6—H6	119.6
O1—Ni1—N1^i	93.12 (8)	C1—C6—H6	119.6
N1—Ni1—N1^i	180.0	N1—C7—C1	126.8 (3)
O1^i—Ni1—N2^i	88.59 (8)	N1—C7—H7	116.6
O1—Ni1—N2^i	91.41 (8)	C1—C7—H7	116.6
N1—Ni1—N2^i	97.37 (9)	N1—C8—C9	109.0 (2)
N1^i—Ni1—N2^i	82.63 (9)	N1—C8—H8A	109.9
O1^i—Ni1—N2	91.41 (8)	C9—C8—H8A	109.9
O1—Ni1—N2	88.59 (8)	N1—C8—H8B	109.9
N1—Ni1—N2	82.63 (9)	C9—C8—H8B	109.9
N1^i—Ni1—N2	97.37 (9)	H8A—C8—H8B	108.3
N2^i—Ni1—N2	180.0	C10—C9—C8	115.1 (3)
C2—O1—Ni1	125.81 (17)	C10—C9—H9A	108.5
C3—O2—C12	116.9 (2)	C8—C9—H9A	108.5
C7—N1—C8	117.4 (2)	C10—C9—H9B	108.5
C7—N1—Ni1	125.5 (2)	C8—C9—H9B	108.5
C8—N1—Ni1	116.60 (19)	H9A—C9—H9B	107.5
C11—N2—C10	110.2 (2)	N2—C10—C9	113.2 (2)
C11—N2—Ni1	116.00 (19)	N2—C10—H10A	108.9
C10—N2—Ni1	114.88 (18)	C9—C10—H10A	108.9
C11—N2—H2	108.1 (16)	N2—C10—H10B	108.9
C10—N2—H2	107.6 (16)	C9—C10—H10B	108.9
Ni1—N2—H2	98.9 (17)	H10A—C10—H10B	107.7
C6—C1—C2	121.0 (3)	N2—C11—H11A	109.5
C6—C1—C7	117.3 (3)	N2—C11—H11B	109.5
C2—C1—C7	121.3 (3)	H11A—C11—H11B	109.5
O1—C2—C1	124.3 (2)	N2—C11—H11C	109.5
O1—C2—C3	120.0 (3)	H11A—C11—H11C	109.5
C1—C2—C3	115.6 (2)	H11B—C11—H11C	109.5
C4—C3—O2	124.0 (3)	O2—C12—H12A	109.5
C4—C3—C2	122.0 (3)	O2—C12—H12B	109.5
O2—C3—C2	114.0 (2)	H12A—C12—H12B	109.5
C3—C4—C5	120.8 (3)	O2—C12—H12C	109.5
C3—C4—H4	119.6	H12A—C12—H12C	109.5
C5—C4—H4	119.6	H12B—C12—H12C	109.5
C6—C5—C4	119.7 (3)

Symmetry code: (i) −x, −y+1, −z+1.