Bis(2-eth­oxy-6-formyl­phenolato-κ2O1,O6)nickel(II)

Han, Z.-Q.

doi:10.1107/S160053680800809X

metal-organic compounds

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ISSN: 2056-9890

Volume 64| Part 4| April 2008| Page m592

doi:10.1107/S160053680800809X

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RETRACTED ARTICLE

This article has been retracted. To view the retraction notice, click here.

Retracted: Bis(2-ethoxy-6-formylphenolato-κ²O¹,O⁶)nickel(II)

Zhen-Quan Han ^a ^*

^aApplied Technical College, Qiqihar University, Qiqihar 161006, People's Republic of China
^*Correspondence e-mail: zhenquan_han@126.com

(Received 18 March 2008; accepted 25 March 2008; online 29 March 2008)

The title compound, [Ni(C₉H₉O₃)₂], was synthesized by the reaction of 3-ethoxysalicylaldehyde with nickel(II) nitrate in methanol solution. The asymmetric unit onsists of two half-molecules; each Ni atom lies on a centre of symmetry. The Ni^II ions are coordinated by four O atoms from two deprotonated 3-ethoxysalicylaldehyde ligands in a slightly distorted square-planar coordination environment.

Related literature

For related literature, see: Carlsson et al. (2004 ); Li & Chen (2006 ); Mounts & Fernando (1974 ); Volkmer et al. (1996 ).

Experimental

Crystal data

[Ni(C₉H₉O₃)₂]
M_r = 389.03
Triclinic, $[P \overline 1]$
a = 8.448 (2) Å
b = 10.123 (2) Å
c = 11.919 (3) Å
α = 111.175 (2)°
β = 97.377 (2)°
γ = 102.431 (3)°
V = 904.1 (4) Å³
Z = 2
Mo Kα radiation
μ = 1.10 mm⁻¹
T = 298 (2) K
0.32 × 0.32 × 0.30 mm

Data collection

Bruker SMART CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 1996 ) T_min = 0.719, T_max = 0.733
5465 measured reflections
3993 independent reflections
3187 reflections with I > 2σ(I)
R_int = 0.013

Refinement

R[F² > 2σ(F²)] = 0.041
wR(F²) = 0.116
S = 1.02
3993 reflections
231 parameters
H-atom parameters constrained
Δρ_max = 0.65 e Å⁻³
Δρ_min = −0.66 e Å⁻³

Table 1
Selected geometric parameters (Å, °)

Ni1—O5	1.837 (2)
Ni1—O4	1.852 (2)
Ni2—O1	1.843 (2)
Ni2—O2	1.851 (2)

O5—Ni1—O5ⁱ	180
O5—Ni1—O4	94.16 (9)
O5ⁱ—Ni1—O4	85.84 (9)
O4—Ni1—O4ⁱ	180
O1—Ni2—O1ⁱⁱ	180
O1—Ni2—O2	93.70 (9)
O1ⁱⁱ—Ni2—O2	86.30 (9)
O2ⁱⁱ—Ni2—O2	180
Symmetry codes: (i) -x, -y+1, -z; (ii) -x, -y, -z.

Data collection: SMART (Bruker, 1998 ); cell refinement: SAINT (Bruker, 1998); data reduction: SAINT; 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 global, I. DOI: 10.1107/S160053680800809X/lh2604sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S160053680800809X/lh2604Isup2.hkl

checkCIF report

Comment top

The authors interest in nickel(II) complexes arises from the fact that Ni(II) is the active center of the urease enzyme (Carlsson et al., 2004; Volkmer et al., 1996). The author reports herein the crystal structure of the title nickel(II) complex.

In the asymmetric unit of the title compound, there are two independent complex (Fig. 1). Each Ni^II ion lies on an inversion center and is coordinated by four O atoms from two deprotonated 3-ethoxysalicylaldehyde ligands. The coordinate bond values (Table 1) in each molecule are comparable to each other between the two independent complex molecules. The structure is similar to other nickel(II) complexes derived from the derivatives of salicylaldehyde (Li & Chen, 2006; Mounts & Fernando, 1974).

Related literature top

For related literature, see: Carlsson et al. (2004); Li & Chen (2006); Mounts & Fernando (1974); Volkmer et al. (1996).

Experimental top

All chemicals were of AR grade. 3-Ethoxysalicylaldehyde (33.2 mg, 0.2 mmol) and nickel(II) nitrate hexahydrate (29.0 mg, 0.1 mmol) were refluxed for 30 min in 10 ml methanol solution. The mixture was cooled to room temperature and filtered. Keeping the filtrate in air for a week, yielded red block crystals suitable for X-ray analysis.

Computing details top

Data collection: SMART (Bruker, 1998); cell refinement: SAINT (Bruker, 1998); data reduction: SAINT (Bruker, 1998); 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 molecular structures of the two centrosymmetric independent molecules, showing 30% probability displacement ellipsoids and the atom-numbering scheme. The unlabeled atoms are related by the symmetry operators (-x, -y+1, -z) and (-x, -y, -z) for the molecules containing Ni1 and Ni2 respectively.

Bis(2-ethoxy-6-formylphenolato-κ²O¹,O⁶)nickel(II) top

Crystal data top

[Ni(C₉H₉O₃)₂]	Z = 2
M_r = 389.03	F(000) = 404
Triclinic, P1	D_x = 1.429 Mg m⁻³
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 8.448 (2) Å	Cell parameters from 2386 reflections
b = 10.123 (2) Å	θ = 2.2–27.9°
c = 11.919 (3) Å	µ = 1.10 mm⁻¹
α = 111.175 (2)°	T = 298 K
β = 97.377 (2)°	Block, red
γ = 102.431 (3)°	0.32 × 0.32 × 0.30 mm
V = 904.1 (4) Å³

Data collection top

Bruker SMART CCD area-detector diffractometer	3993 independent reflections
Radiation source: fine-focus sealed tube	3187 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.013
ω scans	θ_max = 27.5°, θ_min = 2.3°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	h = −10→8
T_min = 0.719, T_max = 0.733	k = −13→13
5465 measured reflections	l = −11→15

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)] = 0.041	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.116	H-atom parameters constrained
S = 1.02	w = 1/[σ²(F_o²) + (0.0596P)² + 0.672P] where P = (F_o² + 2F_c²)/3
3993 reflections	(Δ/σ)_max < 0.001
231 parameters	Δρ_max = 0.65 e Å⁻³
0 restraints	Δρ_min = −0.66 e Å⁻³

Crystal data top

[Ni(C₉H₉O₃)₂]	γ = 102.431 (3)°
M_r = 389.03	V = 904.1 (4) Å³
Triclinic, P1	Z = 2
a = 8.448 (2) Å	Mo Kα radiation
b = 10.123 (2) Å	µ = 1.10 mm⁻¹
c = 11.919 (3) Å	T = 298 K
α = 111.175 (2)°	0.32 × 0.32 × 0.30 mm
β = 97.377 (2)°

Data collection top

Bruker SMART CCD area-detector diffractometer	3993 independent reflections
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	3187 reflections with I > 2σ(I)
T_min = 0.719, T_max = 0.733	R_int = 0.013
5465 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.041	0 restraints
wR(F²) = 0.116	H-atom parameters constrained
S = 1.02	Δρ_max = 0.65 e Å⁻³
3993 reflections	Δρ_min = −0.66 e Å⁻³
231 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	0.0000	0.5000	0.0000	0.02805 (13)
Ni2	0.0000	0.0000	0.0000	0.02920 (14)
O1	0.0505 (2)	−0.0121 (2)	0.15045 (16)	0.0363 (4)
O2	−0.0576 (3)	0.1741 (2)	0.0663 (2)	0.0506 (5)
O3	0.1596 (3)	−0.0689 (2)	0.33683 (18)	0.0484 (5)
O4	0.0529 (3)	0.3494 (3)	−0.1190 (2)	0.0513 (5)
O5	0.1989 (2)	0.63719 (19)	0.02863 (17)	0.0350 (4)
O6	0.4541 (3)	0.8659 (2)	0.1053 (2)	0.0552 (6)
C1	0.3232 (3)	0.4873 (3)	−0.1220 (3)	0.0366 (6)
C2	0.3219 (3)	0.6192 (3)	−0.0278 (2)	0.0328 (5)
C3	0.4641 (3)	0.7438 (3)	0.0107 (3)	0.0416 (7)
C4	0.5959 (4)	0.7345 (4)	−0.0462 (3)	0.0534 (8)
H4	0.6872	0.8170	−0.0214	0.064*
C5	0.5940 (4)	0.6031 (4)	−0.1404 (3)	0.0583 (9)
H5	0.6837	0.5983	−0.1779	0.070*
C6	0.4608 (4)	0.4814 (4)	−0.1777 (3)	0.0508 (8)
H6	0.4606	0.3938	−0.2403	0.061*
C7	0.1866 (3)	0.3570 (3)	−0.1613 (3)	0.0387 (6)
H7	0.1946	0.2713	−0.2220	0.046*
C8	0.5934 (4)	0.9930 (4)	0.1562 (4)	0.0630 (10)
H8A	0.6162	1.0304	0.0939	0.076*
H8B	0.6910	0.9687	0.1859	0.076*
C9	0.5528 (5)	1.1062 (5)	0.2603 (4)	0.0745 (11)
H9A	0.4523	1.1251	0.2308	0.112*
H9B	0.6424	1.1959	0.2933	0.112*
H9C	0.5375	1.0706	0.3238	0.112*
C10	0.0426 (4)	0.2306 (3)	0.2817 (3)	0.0403 (6)
C11	0.0741 (3)	0.0937 (3)	0.2595 (2)	0.0344 (6)
C12	0.1373 (4)	0.0681 (3)	0.3646 (3)	0.0408 (6)
C13	0.1716 (5)	0.1762 (4)	0.4812 (3)	0.0603 (9)
H13	0.2143	0.1582	0.5484	0.072*
C14	0.1433 (6)	0.3135 (4)	0.5010 (3)	0.0737 (12)
H14	0.1689	0.3866	0.5806	0.088*
C15	0.0782 (5)	0.3389 (4)	0.4027 (3)	0.0604 (10)
H15	0.0571	0.4292	0.4158	0.073*
C16	−0.0311 (4)	0.2596 (3)	0.1806 (3)	0.0390 (6)
H16	−0.0617	0.3467	0.1996	0.047*
C17	0.2484 (5)	−0.0970 (4)	0.4322 (3)	0.0552 (8)
H17A	0.1831	−0.0992	0.4930	0.066*
H17B	0.3528	−0.0202	0.4733	0.066*
C18	0.2804 (6)	−0.2441 (5)	0.3720 (4)	0.0832 (14)
H18A	0.1769	−0.3208	0.3414	0.125*
H18B	0.3527	−0.2606	0.4315	0.125*
H18C	0.3322	−0.2449	0.3047	0.125*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Ni1	0.0239 (2)	0.0277 (2)	0.0327 (2)	0.00622 (17)	0.00861 (17)	0.01208 (19)
Ni2	0.0308 (2)	0.0285 (2)	0.0283 (2)	0.00865 (18)	0.00732 (18)	0.01098 (18)
O1	0.0484 (11)	0.0311 (9)	0.0290 (9)	0.0129 (8)	0.0067 (8)	0.0113 (8)
O2	0.0517 (13)	0.0484 (12)	0.0514 (13)	0.0158 (10)	0.0160 (10)	0.0173 (10)
O3	0.0639 (14)	0.0438 (12)	0.0361 (10)	0.0201 (10)	0.0001 (10)	0.0152 (9)
O4	0.0470 (12)	0.0502 (13)	0.0537 (13)	0.0132 (10)	0.0147 (10)	0.0164 (11)
O5	0.0277 (9)	0.0310 (9)	0.0459 (11)	0.0057 (7)	0.0132 (8)	0.0149 (8)
O6	0.0374 (11)	0.0432 (12)	0.0731 (16)	−0.0024 (9)	0.0148 (11)	0.0170 (11)
C1	0.0303 (13)	0.0484 (16)	0.0388 (14)	0.0144 (12)	0.0129 (11)	0.0225 (12)
C2	0.0246 (12)	0.0412 (14)	0.0404 (14)	0.0104 (10)	0.0093 (10)	0.0238 (12)
C3	0.0300 (13)	0.0469 (17)	0.0530 (18)	0.0070 (12)	0.0110 (12)	0.0272 (15)
C4	0.0316 (15)	0.061 (2)	0.072 (2)	0.0021 (14)	0.0163 (15)	0.0362 (18)
C5	0.0380 (17)	0.079 (3)	0.069 (2)	0.0179 (17)	0.0286 (16)	0.036 (2)
C6	0.0414 (16)	0.065 (2)	0.0521 (18)	0.0205 (15)	0.0228 (14)	0.0239 (16)
C7	0.0367 (14)	0.0426 (15)	0.0386 (14)	0.0161 (12)	0.0154 (12)	0.0132 (12)
C8	0.0436 (18)	0.055 (2)	0.076 (3)	−0.0064 (16)	0.0034 (17)	0.0253 (19)
C9	0.073 (3)	0.060 (2)	0.064 (2)	−0.008 (2)	0.005 (2)	0.0134 (19)
C10	0.0472 (16)	0.0387 (15)	0.0354 (14)	0.0168 (13)	0.0131 (12)	0.0114 (12)
C11	0.0318 (13)	0.0374 (14)	0.0314 (13)	0.0086 (11)	0.0091 (10)	0.0110 (11)
C12	0.0423 (15)	0.0421 (15)	0.0341 (14)	0.0127 (12)	0.0064 (12)	0.0115 (12)
C13	0.084 (3)	0.064 (2)	0.0297 (15)	0.030 (2)	0.0049 (16)	0.0120 (15)
C14	0.114 (3)	0.064 (2)	0.0347 (17)	0.041 (2)	0.0089 (19)	0.0036 (16)
C15	0.093 (3)	0.0484 (19)	0.0391 (17)	0.0340 (19)	0.0151 (17)	0.0092 (14)
C16	0.0474 (16)	0.0345 (14)	0.0392 (15)	0.0176 (12)	0.0166 (12)	0.0139 (12)
C17	0.062 (2)	0.065 (2)	0.0424 (17)	0.0247 (17)	0.0015 (15)	0.0249 (16)
C18	0.118 (4)	0.077 (3)	0.062 (2)	0.057 (3)	0.000 (2)	0.027 (2)

Geometric parameters (Å, º) top

Ni1—O5	1.837 (2)	C6—H6	0.9300
Ni1—O5ⁱ	1.837 (2)	C7—H7	0.9300
Ni1—O4	1.852 (2)	C8—C9	1.491 (5)
Ni1—O4ⁱ	1.852 (2)	C8—H8A	0.9700
Ni2—O1	1.843 (2)	C8—H8B	0.9700
Ni2—O1ⁱⁱ	1.843 (2)	C9—H9A	0.9600
Ni2—O2ⁱⁱ	1.851 (2)	C9—H9B	0.9600
Ni2—O2	1.851 (2)	C9—H9C	0.9600
O1—C11	1.309 (3)	C10—C11	1.405 (4)
O2—C16	1.282 (3)	C10—C15	1.406 (4)
O3—C12	1.365 (3)	C10—C16	1.438 (4)
O3—C17	1.429 (3)	C11—C12	1.430 (4)
O4—C7	1.294 (3)	C12—C13	1.369 (4)
O5—C2	1.319 (3)	C13—C14	1.402 (5)
O6—C3	1.367 (4)	C13—H13	0.9300
O6—C8	1.417 (4)	C14—C15	1.362 (5)
C1—C2	1.404 (4)	C14—H14	0.9300
C1—C6	1.412 (4)	C15—H15	0.9300
C1—C7	1.432 (4)	C16—H16	0.9300
C2—C3	1.426 (4)	C17—C18	1.502 (5)
C3—C4	1.380 (4)	C17—H17A	0.9700
C4—C5	1.391 (5)	C17—H17B	0.9700
C4—H4	0.9300	C18—H18A	0.9600
C5—C6	1.364 (5)	C18—H18B	0.9600
C5—H5	0.9300	C18—H18C	0.9600

O5—Ni1—O5ⁱ	180	O6—C8—H8B	110.2
O5—Ni1—O4	94.16 (9)	C9—C8—H8B	110.2
O5ⁱ—Ni1—O4	85.84 (9)	H8A—C8—H8B	108.5
O5—Ni1—O4ⁱ	85.84 (9)	C8—C9—H9A	109.5
O5ⁱ—Ni1—O4ⁱ	94.16 (9)	C8—C9—H9B	109.5
O4—Ni1—O4ⁱ	180	H9A—C9—H9B	109.5
O1—Ni2—O1ⁱⁱ	180	C8—C9—H9C	109.5
O1—Ni2—O2ⁱⁱ	86.30 (9)	H9A—C9—H9C	109.5
O1ⁱⁱ—Ni2—O2ⁱⁱ	93.70 (9)	H9B—C9—H9C	109.5
O1—Ni2—O2	93.70 (9)	C11—C10—C15	120.7 (3)
O1ⁱⁱ—Ni2—O2	86.30 (9)	C11—C10—C16	120.0 (2)
O2ⁱⁱ—Ni2—O2	180	C15—C10—C16	119.3 (3)
C11—O1—Ni2	126.59 (17)	O1—C11—C10	125.3 (2)
C16—O2—Ni2	127.6 (2)	O1—C11—C12	117.4 (2)
C12—O3—C17	118.6 (2)	C10—C11—C12	117.3 (2)
C7—O4—Ni1	127.6 (2)	O3—C12—C13	125.1 (3)
C2—O5—Ni1	127.62 (17)	O3—C12—C11	114.3 (2)
C3—O6—C8	118.6 (3)	C13—C12—C11	120.5 (3)
C2—C1—C6	120.1 (3)	C12—C13—C14	121.2 (3)
C2—C1—C7	120.5 (2)	C12—C13—H13	119.4
C6—C1—C7	119.4 (3)	C14—C13—H13	119.4
O5—C2—C1	125.0 (2)	C15—C14—C13	119.4 (3)
O5—C2—C3	117.0 (2)	C15—C14—H14	120.3
C1—C2—C3	118.0 (2)	C13—C14—H14	120.3
O6—C3—C4	125.7 (3)	C14—C15—C10	120.9 (3)
O6—C3—C2	114.0 (2)	C14—C15—H15	119.6
C4—C3—C2	120.3 (3)	C10—C15—H15	119.6
C3—C4—C5	120.8 (3)	O2—C16—C10	124.7 (3)
C3—C4—H4	119.6	O2—C16—H16	117.6
C5—C4—H4	119.6	C10—C16—H16	117.6
C6—C5—C4	120.2 (3)	O3—C17—C18	107.2 (3)
C6—C5—H5	119.9	O3—C17—H17A	110.3
C4—C5—H5	119.9	C18—C17—H17A	110.3
C5—C6—C1	120.6 (3)	O3—C17—H17B	110.3
C5—C6—H6	119.7	C18—C17—H17B	110.3
C1—C6—H6	119.7	H17A—C17—H17B	108.5
O4—C7—C1	125.0 (3)	C17—C18—H18A	109.5
O4—C7—H7	117.5	C17—C18—H18B	109.5
C1—C7—H7	117.5	H18A—C18—H18B	109.5
O6—C8—C9	107.6 (3)	C17—C18—H18C	109.5
O6—C8—H8A	110.2	H18A—C18—H18C	109.5
C9—C8—H8A	110.2	H18B—C18—H18C	109.5

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

Experimental details

Crystal data
Chemical formula	[Ni(C₉H₉O₃)₂]
M_r	389.03
Crystal system, space group	Triclinic, P1
Temperature (K)	298
a, b, c (Å)	8.448 (2), 10.123 (2), 11.919 (3)
α, β, γ (°)	111.175 (2), 97.377 (2), 102.431 (3)
V (Å³)	904.1 (4)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	1.10
Crystal size (mm)	0.32 × 0.32 × 0.30

Data collection
Diffractometer	Bruker SMART CCD area-detector diffractometer
Absorption correction	Multi-scan (SADABS; Sheldrick, 1996)
T_min, T_max	0.719, 0.733
No. of measured, independent and observed [I > 2σ(I)] reflections	5465, 3993, 3187
R_int	0.013
(sin θ/λ)_max (Å⁻¹)	0.649

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.041, 0.116, 1.02
No. of reflections	3993
No. of parameters	231
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.65, −0.66

Computer programs: SMART (Bruker, 1998), SAINT (Bruker, 1998), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Selected geometric parameters (Å, º) top

Ni1—O5	1.837 (2)	Ni2—O1	1.843 (2)
Ni1—O4	1.852 (2)	Ni2—O2	1.851 (2)

O5—Ni1—O5ⁱ	180	O1—Ni2—O1ⁱⁱ	180
O5—Ni1—O4	94.16 (9)	O1—Ni2—O2	93.70 (9)
O5ⁱ—Ni1—O4	85.84 (9)	O1ⁱⁱ—Ni2—O2	86.30 (9)
O4—Ni1—O4ⁱ	180	O2ⁱⁱ—Ni2—O2	180

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

Acknowledgements

The author acknowledges Qiqihar University for a research grant.

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