Bis{4-chloro-6-formyl-2-[(E)-2-(1H-imidazol-4-yl-κN³)ethyl­imino­methyl-κN]phenolato-κO¹}nickel(II)

In the title compound, [Ni(C₁₃H₁₁ClN₃O₂)₂], the Ni^II atom is located on a twofold rotation axis and is six-coordinated by four N atoms and two phenolate O atoms from the two equal Schiff base ligands in a distorted octa­hedral coordination geometry. The complex mol­ecules are connected by C—H...Cl, C—H...O and N—H...O hydrogen bonds.

Key indicators

• Single-crystal X-ray study
• T = 293 K
• Mean [sigma](C-C) = 0.008 Å
• R factor = 0.045
• wR factor = 0.081
• Data-to-parameter ratio = 13.0

checkCIF/PLATON results

No syntax errors found



Alert level B
RINTA01_ALERT_3_B  The value of Rint is greater than 0.15
            Rint given   0.154

Author Response: This is because of the poor quality and small size of the crystal selected for diffraction. Although many efforts were made to select better crystals for experiment, each time we failed.

PLAT020_ALERT_3_B The value of Rint is greater than 0.10 .........       0.15

Author Response: This is because of the poor quality and small size of the crystal selected for diffraction. Although many efforts were made to select better crystals for experiment, each time we failed.

Alert level C
PLAT341_ALERT_3_C Low Bond Precision on C-C Bonds (x 1000) Ang ...          8

Alert level G
REFLT03_ALERT_4_G Please check that the estimate of the number of Friedel pairs is
            correct. If it is not, please give the correct count in the
            _publ_section_exptl_refinement section of the submitted CIF.
           From the CIF: _diffrn_reflns_theta_max           24.99
           From the CIF: _reflns_number_total               2294
           Count of symmetry unique reflns         1370
           Completeness (_total/calc)            167.45%
           TEST3: Check Friedels for noncentro structure
           Estimate of Friedel pairs measured       924
           Fraction of Friedel pairs measured     0.674
           Are heavy atom types Z>Si present        yes
PLAT199_ALERT_1_G Check the Reported _cell_measurement_temperature        293 K
PLAT200_ALERT_1_G Check the Reported _diffrn_ambient_temperature .        293 K

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

   2 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
   1 ALERT type 4 Improvement, methodology, query or suggestion
   0 ALERT type 5 Informative message, check

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S1. Comment

Transition metal–Schiff base complexes have been an interesting field for a long time due to their striking biological activites (Casella & Gullotti, 1986; Hodnett & Dunn, 1970; Kim et al., 2005; May et al., 2004). In this paper, we report the crystal structure of a new nickel(II) complex with a Schiff base ligand, 2-[(E)-(2-(1H-imidazol-4-yl)ethylimino)methyl]-4-chloro -6-formylphenolate.

In the title compound, the Ni^II atom is located on a twofold rotation axis and six-coordinated by four N atoms and two phenolate O atoms from two Schiff base ligands (Fig. 1). The coordination geometry of the Ni atom can be described as distorted octahedral. The two phenolate O atoms and the two imidazole N atoms are located in the equatorial plane, with Ni—O distance of 2.054 (3)Å and Ni—N distance of 2.068 (4)Å (Table 1), and with the mean plane deviation of 0.0147 (2) Å. The other two N atoms from the imino groups of the Schiff base ligands occupy the axial positions, with somewhat long Ni—N distance of 2.102 (4) Å. The complex molecules are connected by C—H···Cl, C—H···O and N—H···O hydrogen bonds (Table 2).

Related literature

For related literature on transition metal–Schiff base complexes, see: Casella & Gullotti (1986); Hodnett & Dunn (1970); Kim et al. (2005); May et al. (2004). For literature related to the synthesis, see: Taniguchi (1984).

S2. Experimental

2,6-Diformyl-4-chlorophenol was prepared using the method of Taniguchi (1984). The title compound was synthesized by the following procedure: To an acetonitrile solution (10 ml) of 2,6-diformyl-4-chlorophenol (0.092 g, 0.5 mmol) and Ni(ClO₄)₂.6H₂O (0.018 g, 0.25 mmol), a solution of NaOH (0.041 g, 1 mmol) and histamine dihydrochloride (0.092 g, 0.5 mmol) in 15 ml of absolute methanol was added dropwise. After the mixture was stirred at ambient temperature for about 1 h, a red solution appeared and then the stirring was continued for 3 h. Red needle crystals of the title compound suitable for X-ray diffraction were obtained in about a month.

S3. Refinement

H atoms were positioned geometrically and refined as riding atoms, with C—H = 0.93(CH), 0.97(CH₂) Å and N—H = 0.86 Å and with U_iso(H) = 1.2U_eq(C,N).

Computing details

Data collection: SMART (Bruker, 2007); cell refinement: SAINT (Bruker, 2007); data reduction: SAINT (Bruker, 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

Fig. 1. Molecular structure of the title compound. Displacement ellipsoids are drawn at the 30% probability level. [Symmetry code: (i) x, y, -z.]

Bis{4-chloro-6-formyl-2-[(E)-2-(1H-imidazol-4- yl-κN³)ethyliminomethyl-κN]phenolato-κO¹}nickel(II)

Crystal data

[Ni(C13H11ClN3O2)2]	Dx = 1.568 Mg m^−3
Mr = 612.11	Mo Kα radiation, λ = 0.71073 Å
Tetragonal, P43212	Cell parameters from 1360 reflections
Hall symbol: P 4nw 2abw	θ = 2.6–15.1°
a = 13.5883 (16) Å	µ = 1.00 mm^−1
c = 14.0392 (16) Å	T = 293 K
V = 2592.2 (5) Å^3	Needle, red
Z = 4	0.10 × 0.04 × 0.02 mm
F(000) = 1256

Data collection

Bruker SMART APEX CCD area-detector diffractometer	2294 independent reflections
Radiation source: fine-focus sealed tube	1253 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.154
ϕ and ω scans	θmax = 25.0°, θmin = 2.1°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	h = −16→16
Tmin = 0.901, Tmax = 0.978	k = −16→16
21136 measured reflections	l = −14→16

Refinement

Refinement on F^2	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F^2 > 2σ(F^2)] = 0.045	H-atom parameters constrained
wR(F^2) = 0.081	w = 1/[σ^2(Fo^2) + (0.0298P)^2] where P = (Fo^2 + 2Fc^2)/3
S = 0.82	(Δ/σ)max = 0.003
2294 reflections	Δρmax = 0.35 e Å^−3
177 parameters	Δρmin = −0.24 e Å^−3
0 restraints	Absolute structure: Flack (1983), 920 Friedel pairs
Primary atom site location: structure-invariant direct methods	Absolute structure parameter: 0.02 (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. The reason of the large R_intvalue is the poor quality and small size of the crystal sample. Although many efforts were made to select better crystal for experiment, each time we failed.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
Ni1	0.23545 (4)	0.23545 (4)	0.0000	0.0433 (3)
C1	0.2375 (4)	0.0575 (3)	0.1277 (3)	0.0428 (12)
C2	0.2104 (4)	0.0113 (4)	0.2139 (4)	0.0564 (15)
C3	0.2586 (4)	−0.0728 (4)	0.2478 (4)	0.0656 (14)
H3	0.2381	−0.1026	0.3041	0.079*
C4	0.3356 (4)	−0.1106 (4)	0.1977 (5)	0.0642 (17)
C5	0.3666 (4)	−0.0659 (4)	0.1150 (4)	0.0593 (15)
H5	0.4202	−0.0920	0.0825	0.071*
C6	0.3205 (4)	0.0165 (3)	0.0790 (4)	0.0455 (13)
C7	0.1300 (4)	0.0521 (5)	0.2722 (4)	0.0800 (19)
H7	0.1037	0.1125	0.2545	0.096*
C8	0.3581 (3)	0.0522 (4)	−0.0096 (4)	0.0519 (13)
H8	0.4055	0.0129	−0.0384	0.062*
C9	0.3904 (4)	0.1472 (4)	−0.1444 (4)	0.0700 (17)
H9A	0.4022	0.0839	−0.1743	0.084*
H9B	0.4539	0.1760	−0.1294	0.084*
C10	0.3368 (4)	0.2136 (4)	−0.2143 (3)	0.0636 (15)
H10A	0.3701	0.2112	−0.2754	0.076*
H10B	0.2704	0.1892	−0.2233	0.076*
C11	0.3326 (4)	0.3166 (4)	−0.1810 (4)	0.0500 (14)
C12	0.3728 (4)	0.4001 (4)	−0.2169 (4)	0.0620 (16)
H12	0.4097	0.4056	−0.2724	0.074*
C13	0.2960 (3)	0.4340 (4)	−0.0856 (4)	0.0504 (14)
H13	0.2707	0.4695	−0.0345	0.060*
Cl1	0.39581 (12)	−0.21688 (11)	0.23773 (13)	0.1081 (7)
N1	0.3352 (3)	0.1319 (3)	−0.0552 (3)	0.0487 (11)
N2	0.2844 (3)	0.3389 (3)	−0.0971 (3)	0.0480 (11)
N3	0.3486 (3)	0.4739 (3)	−0.1563 (3)	0.0584 (12)
H3A	0.3641	0.5349	−0.1622	0.070*
O1	0.1862 (2)	0.1302 (2)	0.0935 (2)	0.0494 (9)
O2	0.0962 (3)	0.0119 (3)	0.3416 (3)	0.1061 (15)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Ni1	0.0453 (3)	0.0453 (3)	0.0393 (5)	0.0010 (4)	0.0040 (3)	−0.0040 (3)
C1	0.038 (3)	0.050 (3)	0.040 (3)	−0.012 (3)	−0.004 (3)	0.003 (3)
C2	0.057 (4)	0.056 (4)	0.056 (4)	−0.014 (3)	−0.008 (3)	0.009 (3)
C3	0.067 (4)	0.064 (4)	0.066 (4)	−0.024 (3)	−0.020 (5)	0.016 (4)
C4	0.059 (4)	0.055 (4)	0.079 (5)	0.001 (3)	−0.026 (4)	0.017 (4)
C5	0.041 (3)	0.060 (4)	0.077 (5)	−0.003 (3)	−0.011 (3)	−0.002 (3)
C6	0.043 (3)	0.043 (3)	0.050 (4)	−0.003 (3)	−0.006 (3)	0.001 (3)
C7	0.080 (5)	0.115 (5)	0.045 (5)	−0.021 (4)	0.001 (4)	0.030 (4)
C8	0.048 (3)	0.044 (3)	0.064 (4)	0.007 (3)	0.004 (3)	−0.013 (3)
C9	0.094 (4)	0.056 (4)	0.060 (4)	0.015 (3)	0.028 (4)	0.004 (3)
C10	0.082 (4)	0.069 (4)	0.040 (4)	0.011 (3)	0.020 (3)	−0.006 (3)
C11	0.060 (4)	0.053 (4)	0.038 (4)	0.003 (3)	0.002 (3)	0.002 (3)
C12	0.070 (4)	0.068 (4)	0.048 (4)	0.015 (3)	0.018 (3)	0.000 (3)
C13	0.052 (4)	0.054 (4)	0.045 (4)	0.004 (3)	0.009 (3)	0.006 (3)
Cl1	0.1068 (12)	0.0770 (11)	0.1405 (16)	0.0095 (10)	−0.0362 (12)	0.0368 (12)
N1	0.052 (3)	0.054 (3)	0.041 (3)	−0.001 (2)	0.009 (2)	−0.003 (2)
N2	0.063 (3)	0.042 (3)	0.039 (3)	−0.003 (2)	0.003 (2)	0.000 (2)
N3	0.063 (3)	0.053 (3)	0.059 (3)	−0.009 (2)	0.006 (3)	0.018 (3)
O1	0.043 (2)	0.059 (2)	0.046 (2)	0.0090 (17)	0.0044 (17)	0.0083 (18)
O2	0.116 (4)	0.135 (4)	0.068 (4)	−0.013 (3)	0.017 (3)	0.026 (3)

Geometric parameters (Å, º)

Ni1—O1	2.054 (3)	C7—H7	0.9300
Ni1—O1^i	2.054 (3)	C8—N1	1.296 (5)
Ni1—N2^i	2.068 (4)	C8—H8	0.9300
Ni1—N2	2.068 (4)	C9—N1	1.474 (5)
Ni1—N1	2.102 (4)	C9—C10	1.519 (6)
Ni1—N1^i	2.102 (4)	C9—H9A	0.9700
C1—O1	1.301 (5)	C9—H9B	0.9700
C1—C2	1.412 (6)	C10—C11	1.477 (6)
C1—C6	1.431 (6)	C10—H10A	0.9700
C2—C3	1.401 (6)	C10—H10B	0.9700
C2—C7	1.474 (7)	C11—C12	1.355 (6)
C3—C4	1.362 (7)	C11—N2	1.382 (5)
C3—H3	0.9300	C12—N3	1.356 (5)
C4—C5	1.376 (7)	C12—H12	0.9300
C4—Cl1	1.752 (5)	C13—N2	1.312 (5)
C5—C6	1.380 (6)	C13—N3	1.337 (5)
C5—H5	0.9300	C13—H13	0.9300
C6—C8	1.429 (6)	N3—H3A	0.8600
C7—O2	1.208 (5)
O1—Ni1—O1^i	87.37 (17)	C2—C7—H7	117.9
O1—Ni1—N2^i	91.40 (14)	N1—C8—C6	128.9 (5)
O1^i—Ni1—N2^i	178.49 (14)	N1—C8—H8	115.5
O1—Ni1—N2	178.49 (14)	C6—C8—H8	115.5
O1^i—Ni1—N2	91.40 (14)	N1—C9—C10	112.8 (4)
N2^i—Ni1—N2	89.8 (2)	N1—C9—H9A	109.0
O1—Ni1—N1	88.84 (14)	C10—C9—H9A	109.0
O1^i—Ni1—N1	89.72 (13)	N1—C9—H9B	109.0
N2^i—Ni1—N1	91.14 (15)	C10—C9—H9B	109.0
N2—Ni1—N1	90.27 (15)	H9A—C9—H9B	107.8
O1—Ni1—N1^i	89.72 (13)	C11—C10—C9	112.2 (4)
O1^i—Ni1—N1^i	88.84 (14)	C11—C10—H10A	109.2
N2^i—Ni1—N1^i	90.27 (15)	C9—C10—H10A	109.2
N2—Ni1—N1^i	91.14 (15)	C11—C10—H10B	109.2
N1—Ni1—N1^i	178.0 (2)	C9—C10—H10B	109.2
O1—C1—C2	120.9 (5)	H10A—C10—H10B	107.9
O1—C1—C6	122.8 (4)	C12—C11—N2	108.9 (5)
C2—C1—C6	116.2 (5)	C12—C11—C10	131.3 (5)
C3—C2—C1	122.2 (5)	N2—C11—C10	119.7 (5)
C3—C2—C7	117.6 (5)	C11—C12—N3	106.8 (5)
C1—C2—C7	120.2 (5)	C11—C12—H12	126.6
C4—C3—C2	119.4 (5)	N3—C12—H12	126.6
C4—C3—H3	120.3	N2—C13—N3	111.9 (5)
C2—C3—H3	120.3	N2—C13—H13	124.1
C3—C4—C5	120.3 (5)	N3—C13—H13	124.1
C3—C4—Cl1	120.3 (5)	C8—N1—C9	114.6 (4)
C5—C4—Cl1	119.4 (5)	C8—N1—Ni1	122.1 (3)
C4—C5—C6	121.9 (5)	C9—N1—Ni1	123.2 (3)
C4—C5—H5	119.0	C13—N2—C11	105.3 (4)
C6—C5—H5	119.0	C13—N2—Ni1	128.9 (4)
C5—C6—C8	115.6 (5)	C11—N2—Ni1	124.4 (3)
C5—C6—C1	119.9 (5)	C13—N3—C12	107.2 (4)
C8—C6—C1	124.4 (4)	C13—N3—H3A	126.4
O2—C7—C2	124.1 (6)	C12—N3—H3A	126.4
O2—C7—H7	117.9	C1—O1—Ni1	126.1 (3)
O1—C1—C2—C3	173.9 (4)	C10—C9—N1—Ni1	−28.0 (6)
C6—C1—C2—C3	−3.1 (6)	O1—Ni1—N1—C8	−17.2 (4)
O1—C1—C2—C7	−7.0 (7)	O1^i—Ni1—N1—C8	−104.6 (4)
C6—C1—C2—C7	176.0 (4)	N2^i—Ni1—N1—C8	74.1 (4)
C1—C2—C3—C4	1.5 (7)	N2—Ni1—N1—C8	164.0 (4)
C7—C2—C3—C4	−177.6 (5)	O1—Ni1—N1—C9	167.8 (4)
C2—C3—C4—C5	0.8 (8)	O1^i—Ni1—N1—C9	80.4 (4)
C2—C3—C4—Cl1	−179.0 (3)	N2^i—Ni1—N1—C9	−100.8 (4)
C3—C4—C5—C6	−1.3 (8)	N2—Ni1—N1—C9	−11.0 (4)
Cl1—C4—C5—C6	178.5 (4)	N3—C13—N2—C11	−0.2 (5)
C4—C5—C6—C8	−177.3 (5)	N3—C13—N2—Ni1	166.5 (3)
C4—C5—C6—C1	−0.4 (7)	C12—C11—N2—C13	0.6 (6)
O1—C1—C6—C5	−174.4 (4)	C10—C11—N2—C13	178.1 (5)
C2—C1—C6—C5	2.5 (6)	C12—C11—N2—Ni1	−166.8 (3)
O1—C1—C6—C8	2.2 (7)	C10—C11—N2—Ni1	10.7 (6)
C2—C1—C6—C8	179.2 (4)	N2^i—Ni1—N2—C13	−52.1 (4)
C3—C2—C7—O2	−8.3 (8)	N1—Ni1—N2—C13	−143.3 (4)
C1—C2—C7—O2	172.5 (5)	N2^i—Ni1—N2—C11	112.2 (4)
C5—C6—C8—N1	−173.5 (5)	N1—Ni1—N2—C11	21.0 (4)
C1—C6—C8—N1	9.8 (8)	N1^i—Ni1—N2—C11	−157.6 (4)
N1—C9—C10—C11	69.3 (6)	N2—C13—N3—C12	−0.3 (6)
C9—C10—C11—C12	115.1 (6)	C11—C12—N3—C13	0.6 (6)
C9—C10—C11—N2	−61.8 (6)	C2—C1—O1—Ni1	157.3 (3)
N2—C11—C12—N3	−0.7 (6)	C6—C1—O1—Ni1	−25.9 (6)
C10—C11—C12—N3	−177.9 (5)	O1^i—Ni1—O1—C1	118.8 (4)
C6—C8—N1—C9	178.7 (5)	N1—Ni1—O1—C1	29.0 (4)
C6—C8—N1—Ni1	3.3 (7)	N1^i—Ni1—O1—C1	−152.4 (3)
C10—C9—N1—C8	156.6 (4)

Symmetry code: (i) y, x, −z.

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
C9—H9B···Cl1^ii	0.97	2.82	3.475 (5)	125
C12—H12···O2^iii	0.93	2.36	3.287 (7)	174
N3—H3A···O1^iv	0.86	2.06	2.899 (5)	166

Symmetry codes: (ii) −x+1, −y, z−1/2; (iii) y+1/2, −x+1/2, z−3/4; (iv) −y+1/2, x+1/2, z−1/4.