{4,4′-Dimethyl-2,2′-[(2,2-dimethyl­propane-1,3-di­yl)bis­(nitrilo­methanylyl­idene)]diphenolato}nickel(II) monohydrate

In the title compound, [Ni(C₂₁H₂₄N₂O₂)]·H₂O, both the complex mol­ecule and the water mol­ecule lie on a twofold rotation axis. The Ni^II ion is coordinated in a distorted square-planar geometry by the tetra­dentate ligand. The dihedral angle between the two symmetry-related benzene rings is 47.12 (8)°. In the crystal, pairs of symmetry-related O—H...O hydrogen bonds form R₂²(6) ring motifs. In addition, there are weak inter­molecular C—H...O hydrogen bonds, and π–π stacking inter­actions with a centroid–centroid distance of 3.4760 (8) Å.

Key indicators

• Single-crystal X-ray study
• T = 296 K
• Mean [sigma](C-C) = 0.003 Å
• R factor = 0.031
• wR factor = 0.083
• Data-to-parameter ratio = 20.5

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT242_ALERT_2_C Check Low       Ueq as Compared to Neighbors for        C10
PLAT910_ALERT_3_C Missing # of FCF Reflections Below Th(Min) .....          1

Alert level G
PLAT005_ALERT_5_G No _iucr_refine_instructions_details in CIF ....          ?
PLAT232_ALERT_2_G Hirshfeld Test Diff (M-X)  Ni1    --  O1      ..        7.1 su
PLAT232_ALERT_2_G Hirshfeld Test Diff (M-X)  Ni1    --  N1      ..        8.3 su

   0 ALERT level A = Most likely a serious problem - resolve or explain
   0 ALERT level B = A potentially serious problem, consider carefully
   2 ALERT level C = Check. Ensure it is not caused by an omission or oversight
   3 ALERT level G = General information/check it is not something unexpected

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

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S1. Comment

In continuation of our work on the crystal structures of a Schiff base ligands and complexes (Fun et al., 2008; Kargar et al., 2008,2011; Rayati et al., 2011; Kia et al., 2010), we have determined the X-ray structure of the title compound.

The molecular structure of the title compound is ahown in Fig. 1. The asymmetric unit comprises half of Schiff base complex and half a water molecule. The Ni^II ion, the central carbon atom of the diamine segment (C10) and the O atom of water molecule lie on a two-fold rotation axis. The coordination geometry of Ni1 is distorted square-planar formed by the tetradentate ligand. The bond lengths (Allen et al., 1987) and angles are within the normal ranges and are comparable to related structures (Fun et al. 2008; Kargar et al. 2008; Rayati et al., 2011). The dihedral angle between the two symmetry related benzene rings is 47.12 (8)°. A pair of symmetry related intermolecular O—H···O hydrogen bonds form an R²₂(6) ring motif (Bernstein et al., 1995). In the crystal, molecules are linked through weak intermolecular C—H···O interactions. The crystal structure is further stabilized by intermolecular π–π interactions [Cg1···Cg1ⁱⁱⁱ = 3.4760 (8)Å; (iii) -x, 1 - y, 1 - z; Cg1 is the centroid of the Ni1/O1/C1/C6/C8/N1 ring].

Related literature

For related structures, see for example: Fun et al. (2008); Kargar et al. (2008, 2011); Rayati et al. (2011); Kia et al. (2010). For standard bond lengths, see: Allen et al. (1987). For hydrogen-bond motifs, see: Bernstein et al. (1995).

S2. Experimental

The title compound was synthesized by adding bis(5-methylsalicylaldehyde)-2,2-dimethyl-1,3-propanediimine (2 mmol) to a solution of nickel(II) chloride hexahydrate (2.1 mmol) in ethanol (30 ml). The mixture was refluxed with stirring for half an hour. The resultant solution was filtered. Yellow single crystals of the title compound suitable for X-ray structure determination were recrystallized from an ethanol solution of the title compound by slow evaporation of the solvent at room temperature over several days.

S3. Refinement

Hydrogen atoms bonded to C atoms were positioned geometrically with C—H = 0.93-0.97 Å and included in a riding model approximation with U_iso (H) = 1.2 or 1.5 U_eq (C) The unique water H atom was located in a difference Fourier map and then constrained to ride to the parent atom with U_iso (H) = 1.5 U_eq (O). A rotating group model was used only for the benzene- substituent methyl group.

Computing details

Data collection: APEX2 (Bruker, 2005); cell refinement: SAINT (Bruker, 2005); data reduction: SAINT (Bruker, 2005); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures

	Fig. 1. The molecular structure of the title compound, showing 40% probability displacement ellipsoids. The dashed lines show hydrogen bonds [symmetry code: (A) -x, y, -z+1/2].
	Fig. 2. A partial packing diagram of the title compound viewed approximately along the c-axis showing molecules linked through intermolecular hydrogen bonds (dashed lines). Only the H atoms involved in the interactions are shown.

{4,4'-Dimethyl-2,2'-[(2,2-dimethylpropane-1,3- diyl)bis(nitrilomethanylylidene)]diphenolato}nickel(II) monohydrate

Crystal data

[Ni(C21H24N2O2)]·H2O	F(000) = 872
Mr = 413.15	Dx = 1.335 Mg m^−3
Monoclinic, C2/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2yc	Cell parameters from 3245 reflections
a = 13.3333 (4) Å	θ = 2.8–27.8°
b = 15.9424 (5) Å	µ = 0.97 mm^−1
c = 9.9965 (3) Å	T = 296 K
β = 104.736 (1)°	Block, red
V = 2055.01 (11) Å^3	0.25 × 0.12 × 0.08 mm
Z = 4

Data collection

Bruker SMART APEXII CCD area-detector diffractometer	2557 independent reflections
Radiation source: fine-focus sealed tube	2131 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.040
ϕ and ω scans	θmax = 28.3°, θmin = 2.6°
Absorption correction: multi-scan (SADABS; Bruker, 2005)	h = −17→16
Tmin = 0.794, Tmax = 0.927	k = −21→21
17468 measured reflections	l = −13→13

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)] = 0.031	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.083	H-atom parameters constrained
S = 1.06	w = 1/[σ^2(Fo^2) + (0.0485P)^2] where P = (Fo^2 + 2Fc^2)/3
2557 reflections	(Δ/σ)max < 0.001
125 parameters	Δρmax = 0.21 e Å^−3
0 restraints	Δρmin = −0.31 e Å^−3

Special details

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 > 2sigma(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	0.489837 (15)	0.2500	0.03589 (11)
O1	0.09186 (9)	0.57316 (6)	0.34800 (11)	0.0457 (3)
N1	0.04523 (10)	0.40475 (8)	0.39178 (12)	0.0414 (3)
C1	0.16634 (12)	0.56212 (9)	0.46203 (15)	0.0401 (3)
C2	0.23779 (14)	0.62692 (10)	0.50786 (17)	0.0497 (4)
H2A	0.2346	0.6747	0.4537	0.060*
C3	0.31279 (14)	0.62162 (12)	0.63132 (18)	0.0567 (5)
H3A	0.3589	0.6660	0.6581	0.068*
C4	0.32147 (14)	0.55163 (13)	0.71719 (17)	0.0550 (4)
C5	0.25490 (14)	0.48675 (11)	0.67168 (18)	0.0487 (4)
H5A	0.2604	0.4390	0.7265	0.058*
C6	0.17758 (13)	0.48878 (9)	0.54427 (17)	0.0410 (3)
C7	0.40114 (17)	0.54821 (18)	0.85526 (19)	0.0817 (7)
H7A	0.4556	0.5101	0.8494	0.123*
H7B	0.3687	0.5292	0.9252	0.123*
H7C	0.4297	0.6031	0.8788	0.123*
C8	0.11388 (13)	0.41566 (10)	0.50691 (15)	0.0431 (4)
H8A	0.1230	0.3725	0.5714	0.052*
C9	−0.01669 (14)	0.32780 (10)	0.36982 (16)	0.0488 (4)
H9A	−0.0895	0.3426	0.3512	0.059*
H9B	0.0006	0.2949	0.4542	0.059*
C10	0.0000	0.27358 (15)	0.2500	0.0564 (7)
C11	0.0973 (2)	0.21930 (15)	0.2981 (2)	0.1038 (9)
H11A	0.1569	0.2548	0.3287	0.156*
H11B	0.1057	0.1851	0.2226	0.156*
H11C	0.0903	0.1840	0.3729	0.156*
O1W	0.0000	0.72531 (12)	0.2500	0.0992 (8)
H1	−0.0556	0.6878	0.2007	0.149*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Ni1	0.03715 (18)	0.03024 (16)	0.03666 (16)	0.000	0.00274 (11)	0.000
O1	0.0462 (7)	0.0353 (6)	0.0472 (6)	−0.0002 (5)	−0.0032 (5)	0.0020 (5)
N1	0.0448 (8)	0.0367 (7)	0.0424 (7)	−0.0023 (6)	0.0110 (6)	0.0012 (5)
C1	0.0364 (8)	0.0408 (8)	0.0418 (8)	0.0035 (6)	0.0075 (6)	−0.0040 (6)
C2	0.0470 (10)	0.0449 (9)	0.0540 (9)	−0.0035 (7)	0.0069 (8)	−0.0022 (7)
C3	0.0434 (10)	0.0635 (12)	0.0586 (10)	−0.0101 (8)	0.0047 (8)	−0.0118 (9)
C4	0.0391 (10)	0.0794 (13)	0.0432 (9)	−0.0003 (9)	0.0042 (7)	−0.0047 (9)
C5	0.0428 (10)	0.0604 (11)	0.0413 (8)	0.0055 (8)	0.0076 (7)	0.0051 (7)
C6	0.0373 (9)	0.0449 (9)	0.0390 (8)	0.0040 (7)	0.0065 (7)	−0.0010 (6)
C7	0.0590 (14)	0.121 (2)	0.0537 (11)	−0.0122 (13)	−0.0074 (10)	−0.0005 (12)
C8	0.0472 (10)	0.0411 (8)	0.0408 (8)	0.0029 (7)	0.0109 (7)	0.0055 (6)
C9	0.0603 (11)	0.0394 (9)	0.0494 (9)	−0.0103 (8)	0.0189 (8)	0.0006 (7)
C10	0.0806 (19)	0.0355 (12)	0.0563 (14)	0.000	0.0236 (14)	0.000
C11	0.159 (3)	0.0726 (15)	0.0929 (16)	0.0629 (16)	0.0553 (17)	0.0332 (13)
O1W	0.1069 (18)	0.0426 (11)	0.1201 (18)	0.000	−0.0225 (15)	0.000

Geometric parameters (Å, º)

Ni1—O1	1.901 (1)	C5—H5A	0.9300
Ni1—O1^i	1.9010 (10)	C6—C8	1.435 (2)
Ni1—N1^i	1.9436 (12)	C7—H7A	0.9600
Ni1—N1	1.9436 (12)	C7—H7B	0.9600
O1—C1	1.3194 (17)	C7—H7C	0.9600
N1—C8	1.2870 (19)	C8—H8A	0.9300
N1—C9	1.4638 (19)	C9—C10	1.539 (2)
C1—C2	1.401 (2)	C9—H9A	0.9700
C1—C6	1.415 (2)	C9—H9B	0.9700
C2—C3	1.379 (2)	C10—C11	1.532 (2)
C2—H2A	0.9300	C10—C11^i	1.532 (2)
C3—C4	1.394 (3)	C10—C9^i	1.539 (2)
C3—H3A	0.9300	C11—H11A	0.9600
C4—C5	1.364 (3)	C11—H11B	0.9600
C4—C7	1.513 (2)	C11—H11C	0.9600
C5—C6	1.421 (2)	O1W—H1	0.9818
O1—Ni1—O1^i	91.34 (6)	C4—C7—H7A	109.5
O1—Ni1—N1^i	154.58 (6)	C4—C7—H7B	109.5
O1^i—Ni1—N1^i	94.14 (5)	H7A—C7—H7B	109.5
O1—Ni1—N1	94.14 (5)	C4—C7—H7C	109.5
O1^i—Ni1—N1	154.58 (6)	H7A—C7—H7C	109.5
N1^i—Ni1—N1	91.48 (7)	H7B—C7—H7C	109.5
C1—O1—Ni1	126.63 (9)	N1—C8—C6	125.58 (15)
C8—N1—C9	119.54 (13)	N1—C8—H8A	117.2
C8—N1—Ni1	125.16 (11)	C6—C8—H8A	117.2
C9—N1—Ni1	114.64 (10)	N1—C9—C10	113.57 (13)
O1—C1—C2	118.94 (14)	N1—C9—H9A	108.9
O1—C1—C6	123.87 (14)	C10—C9—H9A	108.9
C2—C1—C6	117.16 (15)	N1—C9—H9B	108.9
C3—C2—C1	121.69 (16)	C10—C9—H9B	108.9
C3—C2—H2A	119.2	H9A—C9—H9B	107.7
C1—C2—H2A	119.2	C11—C10—C11^i	111.2 (3)
C2—C3—C4	121.84 (17)	C11—C10—C9^i	106.43 (11)
C2—C3—H3A	119.1	C11^i—C10—C9^i	110.61 (11)
C4—C3—H3A	119.1	C11—C10—C9	110.61 (11)
C5—C4—C3	117.16 (16)	C11^i—C10—C9	106.43 (11)
C5—C4—C7	121.55 (19)	C9^i—C10—C9	111.63 (18)
C3—C4—C7	121.28 (19)	C10—C11—H11A	109.5
C4—C5—C6	122.98 (17)	C10—C11—H11B	109.5
C4—C5—H5A	118.5	H11A—C11—H11B	109.5
C6—C5—H5A	118.5	C10—C11—H11C	109.5
C1—C6—C5	119.02 (15)	H11A—C11—H11C	109.5
C1—C6—C8	123.49 (15)	H11B—C11—H11C	109.5
C5—C6—C8	117.48 (14)
O1^i—Ni1—O1—C1	163.48 (15)	C7—C4—C5—C6	178.41 (17)
N1^i—Ni1—O1—C1	−93.95 (16)	O1—C1—C6—C5	−174.24 (15)
N1—Ni1—O1—C1	8.32 (13)	C2—C1—C6—C5	4.2 (2)
O1—Ni1—N1—C8	1.34 (13)	O1—C1—C6—C8	5.0 (2)
O1^i—Ni1—N1—C8	−100.61 (16)	C2—C1—C6—C8	−176.58 (15)
N1^i—Ni1—N1—C8	156.53 (16)	C4—C5—C6—C1	−2.0 (3)
O1—Ni1—N1—C9	171.99 (11)	C4—C5—C6—C8	178.70 (16)
O1^i—Ni1—N1—C9	70.04 (15)	C9—N1—C8—C6	−177.90 (15)
N1^i—Ni1—N1—C9	−32.82 (8)	Ni1—N1—C8—C6	−7.7 (2)
Ni1—O1—C1—C2	169.47 (11)	C1—C6—C8—N1	5.6 (3)
Ni1—O1—C1—C6	−12.1 (2)	C5—C6—C8—N1	−175.14 (16)
O1—C1—C2—C3	175.28 (15)	C8—N1—C9—C10	−117.17 (16)
C6—C1—C2—C3	−3.2 (2)	Ni1—N1—C9—C10	71.61 (15)
C1—C2—C3—C4	−0.1 (3)	N1—C9—C10—C11	82.3 (2)
C2—C3—C4—C5	2.4 (3)	N1—C9—C10—C11^i	−156.78 (16)
C2—C3—C4—C7	−177.33 (18)	N1—C9—C10—C9^i	−36.00 (9)
C3—C4—C5—C6	−1.3 (3)

Symmetry code: (i) −x, y, −z+1/2.

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O1W—H1···O1^i	0.98	1.92	2.781 (2)	145
C3—H3A···O1W^ii	0.93	2.55	3.477 (2)	173

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