Bis[2-hydr­oxy-N′-(3-phenyl­prop-2-enyl­idene)benzohydrazidato-κ²N′,O]bis­(methanol-κO)nickel(II) and bis­[2-hydr­oxy-N′-(3-phenyl­prop-2-enyl­idene)benzohydrazidato-κ²N′,O]bis(pyridine-κN)nickel(II)

In the two title complexes of cinnamaldehyde salicyloylhydra­zone [or 2-hydr­oxy-N′-(3-phenyl­prop-2-enyl­idene)­benzo­hy­dra­zide], [Ni(C₁₆H₁₃N₂O₂)₂(CH₄O)₂], (I), and [Ni(C₁₆H₁₃N₂O₂)₂(C₅H₅N)₂], (II), the Ni^II atoms lie on crystallographic inversion centres and have distorted octa­hedral geometries. The equatorial plane is defined by two carbonyl O atoms and two hydrazine N atoms of two bidentate trans-oriented salicyloylhydrazone ligands. The axial positions are occupied by two O atoms from two coordinated methanol mol­ecules in (I) and by two N atoms from two coordinated pyridine mol­ecules in (II). There is an extended chain structure in (I) resulting from inter­molecular O—H...O hydrogen bonds between coordinated methanol mol­ecules and phenol O atoms, while (II) comprises discrete mol­ecules. Complex (I) also exhibits weak π–π stacking inter­actions, and intra­molecular O—H...N hydrogen bonds are present in both (I) and (II). The salicyloylhydrazone ligands in (I) and (II) are coordinated to the metal atom through the carbohydrazide O and N² atoms, not via the phenol O atom. We have established a link between the reagents used and the nuclearity of the complex formed: the ligand produced by condensation between salicylhydrazide and an aldehyde leads to mononuclear complexes, while replacing the aldehyde in the reaction by a ketone leads to multinuclear complexes.

S1. Comment

The design and construction of the hydrazone complexes are of great interest, due to their intriguing structural topologies and potential applications (Sreekanth et al., 2004; Bai et al., 2006). To date, only a few structures of cinnamaldehyde hydrazone complexes have been reported (Son et al., 2002; Chumakov et al., 2006), although many hydrazone complexes have been synthesized and characterized. We present here the syntheses and structural characterization of the title nickel(II) complexes, [NiL₂(CH₃OH)₂], (I), and [NiL₂(C₅H₅N)₂], (II), where L⁻ is the monoanionic cinnamaldehyde salicyloylhydrazone. To the best of our knowledge, the title complexes represent the first examples of structurally characterized cinnamaldehyde salicyloylhydrazone complexes.

As shown in Fig. 1, compound (I) contains a distorted octahedrally coordinated Ni^II ion located on a crystallographic inversion centre, with two cinnamaldehyde salicyloylhydrazone L⁻ ligands acting in a bidentate manner to form five-membered chelate rings. Two methanol molecules coordinate axially via their O atoms. The four atoms O2, O2ⁱ, N2 and N2ⁱ [symmetry code: (i) −x + 1, −y, −z + 1] of the two hydrazone ligands form the equatorial plane, while the two O atoms (O3 and O3ⁱ) from the methanol molecules occupy the two axial positions. The Ni1—N2(hydrazine) bond distance of 2.0845 (15) Å in (I) is longer than the corresponding Ni—N values of 1.988 (2), 1.995 (2) and 1.983 (2) Å in similar complexes (Table 1). The Ni1—O3(methanol) bond length of 2.0970 (14) Å in (I) falls within the range 2.0661 (7)–2.148 (3) Å found for octahedral nickel complexes containing CH₃OH in axial positions (Table 2).

The Ni^II centre in complex (II) displays a slightly distorted octahedral coordination and lies on the inversion centre. The Ni^II centre is coordinated by two O (O2 and O2ⁱ) and two N atoms (N2 and N2ⁱ) of two cinnamaldehyde salicyloylhydrazone L⁻ ligands [symmetry code: (i) −x, −y + 1, −z + 1], and two N atoms (N3 and N3ⁱ ) of two coordinated pyridine molecules (see Fig. 2). In the equatorial plane, the Ni1—N2(hydrazine) bond distances of 2.082 (2) Å and Ni1—O2(carboxyl) bond distances of 2.0182 (15) Å are similar to the corresponding values in (I). The Ni1—N3(pyridine) bond length of 2.1487 (19) Å lies within the range 2.140 (2)—2.165 (2) Å found for related nickel complexes (Table 3).

The dihedral angles between the two benzene rings (C1–C6 and C11–C16) of the hydrazone ligand in complexes (I) and (II) are 8.1 (1) and 18.8 (1)°, respectively. These values indicate slightly different degrees of coplanarity for the cinnamaldehyde salicyloylhydrazone ligands in the two complexes.

Adjacent complex molecules in (I) are linked by two intermolecular O—H(methanol)···Oⁱⁱ(phenol) hydrogen bonds [symmetry code: (ii) x, y − 1, z] to form an extended one-dimensional chain along the b axis (see Table 4 and Fig. 3). However, as there is no comparable intermolecular hydrogen bonding in (II), this complex exists as discrete molecules. There are intramolecular O—H(phenol)···N(hydrazine) hydrogen bonds in complexes (I) and (II), forming a six-membered ring (H1/O1/C1/C2/C7/N1) (Tables 4 and 5).

The structure of (I) also exhibits weak π–π stacking interactions between the C9═C10 double bond and the phenyl ring (C1–C6) in adjacent molecules (Fig. 3). The distance between their centroids is 3.467 (1) Å.

Important structural conclusions can be drawn from the synthetic reactions and structural characterization of known salicyloylhydrazone complexes and the salicyloylhydrazone complexes synthesized in our group. Firstly, the salicyloylhydrazone product of the condensation between salicylhydrazide and an aldehyde coordinates to a metal atom through its carboxyl O atom and hydrazine N atoms, not via its phenolate O atom. Therefore, the salicyloylhydrazone complexes formed between a metal and this type of hydrazone are usually mononuclear (Bonardi et al., 1991; Bermejo et al., 2000; Dang et al., 2006) (see top of second scheme). Secondly, when a salicyloylhydrazone is synthesized by condensation between salicylhydrazide and a ketone, the salicyloylhydrazone is coordinated through its carboxyl O atom, hydrazine N atom and phenolate O atom. Therefore, this type of hydrazone ligand is trianionic, and the salicyloylhydrazone complexes formed between a metal and this type of hydrazone are usually linear multinuclear or cyclic multinuclear complexes (Liu et al., 2001; John et al., 2005; Moon et al., 2006) (see bottom of second scheme).

S2. Experimental

The ligand H₂L was prepared by the reaction of salicyloylhydrazide and cinnamaldehyde in a molar ratio of 1:1 under reflux in ethanol for 2 h. The yellow product obtained on cooling was washed first with anhydrous ethanol and then with ethoxyethane.

H₂L (0.1 mmol, 27 mg) and NiCl₂·6H₂O (0.1 mmol, 24 mg) were dissolved in a mixture of CH₃OH (8 ml) and CH₂Cl₂ (8 ml). The mixed solution was stirred for 1 h and then filtered. Yellow block-like crystals of complex (I) were obtained after 4 d.

H₂L (0.1 mmol, 27 mg) and NiCl₂·6H₂O (0.1 mmol, 24 mg) were dissolved in a mixture of CH₃OH (8 ml) and CH₂Cl₂ (8 ml). After stirring for 5 min, one drop of pyridine was added to the mixed solution, which was stirred for another 1 h and filtered. Yellow prismatic crystals of complex (II) were formed after 3 d.

The band at 3255 cm⁻¹ in the IR spectrum of the free cinnamaldehyde salicyloylhydrazone ligand is assigned to ν(NH) (Casabó et al., 1989). This absorption of ν(NH) is absent in the IR spectra of the two title nickel complexes, suggesting that the diazine N atom in the two complexes is coordinated to a Ni^II centre and that the hydrazone ligand is monoanionic. The bands at 3051 cm⁻¹ in (I) and 3055 cm⁻¹ in (II) are due to ν(OH) of the phenolate (Ding, Hu & Zhang, 2006 or Ding, Zhang et al., 2006 ?). Two bands at 1521 cm⁻¹ and 1563 cm⁻¹ in the spectrum of (II) are assigned to ν[C═ N—N═C(O⁻)] of the hydrazone and the coordinated pyridine N atom (Hu et al., 2006). The thermogravimetric and differential thermal analysis curves of complex (II) show that the decomposition of the mixed-ligand complex occurs in two regions. Loss of two pyridine molecules takes place in the first region between 436 and 531 K with a mass loss of 21.96% (calculated 21.14%). The second stage between 556 and 773 K corresponds to decomposition of the ligands with a mass loss of 68.43% (calculated 70.90%). The complex finally degraded completely into NiO with a mass of 9.01% (calculated 9.99%).

S3. Refinement

The H atom of the phenolate OH group in (I) and (II) and the H atom of the CH₃OH molecule in (I) were located in difference Fourier maps, and then allowed to ride on their parent O atoms, with U_eq(H) = 1.5U_eq(O) and O—H between 0.948 and 0.975 Å. The other H atoms in (I) and (II) were placed in idealized positions and treated as riding, with C—H = 0.93 Å and U_iso(H) = 1.2U_eq(C) for aromatic H, and C—H = 0.96 Å and U_iso(H) = 1.5U_eq(C) for methyl H.

Computing details

For both compounds, data collection: TEXRAY (Molecular Structure Corporation, 1999); cell refinement: TEXRAY (Molecular Structure Corporation, 1999); data reduction: TEXSAN (Molecular Structure Corporation, 1999); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEX (McArdle, 1995); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures

	Fig. 1. A view of compound (I), showing the atomic numbering scheme. Displacement ellipsoids are drawn at the 30% probability level. Dashed lines indicate hydrogen bonding. H atoms not involved in the hydrogen bonding have been omitted for clarity. [Symmetry code: (i) x, −y, 1 − z.]
	Fig. 2. A view of compound (II), showing the atomic numbering scheme. Displacement ellipsoids are drawn at the 30% probability level. Dashed lines indicate hydrogen bonding. H atoms not involved in the hydrogen bonding have been omitted for clarity. [Symmetry code: (i) −x, 1 − y, 1 − z.]
	Fig. 3. A packing diagram for (I), with hydrogen bonds shown as dashed lines and π–π stacking shown as double-dashed lines. H atoms not involved in hydrogen bonding have been omitted.

(I) Bis[2-hydroxy-N'-(3-phenylprop-2-enylidene)benzohydrazidato- κ²N,O]bis(methanol-κO)nickel(II)

Crystal data

[Ni(C16H13N2O2)2(CH4O)2]	Dx = 1.353 Mg m^−3
Mr = 653.36	Mo Kα radiation, λ = 0.71073 Å
Orthorhombic, Pbca	Cell parameters from 3677 reflections
a = 17.536 (5) Å	θ = 3.3–27.5°
b = 8.016 (2) Å	µ = 0.66 mm^−1
c = 22.814 (8) Å	T = 293 K
V = 3207.2 (17) Å^3	Block, yellow
Z = 4	0.31 × 0.25 × 0.20 mm
F(000) = 1368

Data collection

Rigaku R-AXIS RAPID Imaging Plate diffractometer	3677 independent reflections
Radiation source: fine-focus sealed tube	2696 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.046
ω scans	θmax = 27.5°, θmin = 3.3°
Absorption correction: multi-scan (TEXRAY; Molecular Structure Corporation, 1999)	h = −22→22
Tmin = 0.721, Tmax = 0.906	k = −10→9
27936 measured reflections	l = −29→29

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) = 0.102	H-atom parameters constrained
S = 1.06	w = 1/[σ^2(Fo^2) + (0.0497P)^2 + 0.7005P] where P = (Fo^2 + 2Fc^2)/3
3677 reflections	(Δ/σ)max = 0.001
206 parameters	Δρmax = 0.25 e Å^−3
0 restraints	Δρmin = −0.42 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.

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

	x	y	z	Uiso*/Ueq
Ni1	0.5000	0.0000	0.5000	0.03518 (11)
O1	0.64110 (8)	0.58785 (16)	0.49628 (5)	0.0478 (3)
H1	0.6077	0.5057	0.5120	0.072*
O2	0.54359 (7)	0.14615 (14)	0.43587 (5)	0.0441 (3)
N1	0.56470 (9)	0.32859 (18)	0.51127 (7)	0.0407 (3)
N2	0.52531 (8)	0.21672 (17)	0.54659 (6)	0.0379 (3)
C1	0.64876 (10)	0.5423 (2)	0.43998 (9)	0.0423 (4)
C2	0.61404 (10)	0.3961 (2)	0.41775 (8)	0.0391 (4)
C3	0.62221 (11)	0.3582 (2)	0.35885 (9)	0.0481 (4)
H3	0.5984	0.2637	0.3438	0.058*
C4	0.66491 (13)	0.4578 (3)	0.32213 (10)	0.0549 (5)
H4	0.6696	0.4313	0.2826	0.066*
C5	0.70066 (12)	0.5972 (3)	0.34458 (10)	0.0561 (5)
H5	0.7303	0.6634	0.3201	0.067*
C6	0.69303 (11)	0.6393 (2)	0.40242 (10)	0.0524 (5)
H6	0.7177	0.7335	0.4168	0.063*
C7	0.57072 (9)	0.2811 (2)	0.45565 (8)	0.0374 (4)
C8	0.51641 (10)	0.2663 (2)	0.59974 (8)	0.0430 (4)
H8	0.5384	0.3673	0.6105	0.052*
C9	0.47495 (11)	0.1762 (2)	0.64321 (8)	0.0437 (4)
H9	0.4528	0.0742	0.6340	0.052*
C10	0.46797 (11)	0.2387 (3)	0.69731 (8)	0.0474 (4)
H10	0.4953	0.3357	0.7050	0.057*
C11	0.42278 (11)	0.1732 (3)	0.74552 (8)	0.0480 (4)
C12	0.37153 (12)	0.0419 (3)	0.73913 (9)	0.0572 (5)
H12	0.3661	−0.0099	0.7029	0.069*
C13	0.32865 (15)	−0.0120 (4)	0.78620 (11)	0.0731 (7)
H13	0.2943	−0.0994	0.7815	0.088*
C14	0.33662 (17)	0.0630 (5)	0.83975 (11)	0.0846 (9)
H14	0.3079	0.0260	0.8715	0.102*
C15	0.38651 (18)	0.1915 (5)	0.84669 (10)	0.0886 (9)
H15	0.3918	0.2419	0.8832	0.106*
C16	0.42918 (14)	0.2474 (3)	0.79998 (10)	0.0680 (6)
H16	0.4627	0.3361	0.8051	0.082*
O3	0.60897 (7)	−0.09436 (16)	0.51828 (6)	0.0503 (3)
H18	0.6123	−0.2082	0.5073	0.075*
C17	0.67884 (13)	−0.0134 (3)	0.52493 (16)	0.0794 (8)
H17D	0.7160	−0.0908	0.5396	0.119*
H17A	0.6733	0.0773	0.5521	0.119*
H17B	0.6953	0.0291	0.4877	0.119*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Ni1	0.03923 (18)	0.02983 (17)	0.03647 (18)	−0.00613 (12)	0.00374 (12)	−0.00047 (12)
O1	0.0534 (8)	0.0366 (7)	0.0534 (8)	−0.0093 (6)	0.0001 (6)	−0.0004 (6)
O2	0.0555 (7)	0.0352 (6)	0.0416 (7)	−0.0124 (6)	0.0057 (6)	−0.0009 (5)
N1	0.0442 (8)	0.0332 (7)	0.0446 (9)	−0.0060 (6)	0.0072 (6)	0.0010 (6)
N2	0.0395 (7)	0.0345 (7)	0.0396 (8)	−0.0028 (6)	0.0027 (6)	−0.0005 (6)
C1	0.0371 (9)	0.0351 (8)	0.0548 (11)	0.0003 (7)	−0.0001 (8)	0.0066 (8)
C2	0.0374 (8)	0.0325 (8)	0.0472 (10)	0.0006 (7)	0.0040 (7)	0.0054 (8)
C3	0.0532 (11)	0.0411 (10)	0.0499 (11)	−0.0008 (9)	0.0085 (9)	0.0022 (9)
C4	0.0599 (12)	0.0538 (11)	0.0510 (12)	0.0042 (10)	0.0154 (10)	0.0081 (10)
C5	0.0503 (11)	0.0500 (11)	0.0680 (14)	−0.0027 (9)	0.0162 (10)	0.0177 (11)
C6	0.0477 (10)	0.0413 (10)	0.0682 (14)	−0.0087 (9)	0.0032 (9)	0.0083 (10)
C7	0.0366 (8)	0.0309 (8)	0.0448 (10)	−0.0017 (7)	0.0029 (7)	0.0022 (7)
C8	0.0449 (9)	0.0390 (9)	0.0450 (10)	−0.0032 (8)	0.0004 (8)	−0.0059 (8)
C9	0.0474 (9)	0.0430 (9)	0.0406 (9)	−0.0010 (9)	0.0022 (8)	−0.0038 (8)
C10	0.0504 (10)	0.0491 (10)	0.0427 (10)	−0.0016 (9)	−0.0023 (8)	−0.0070 (9)
C11	0.0506 (10)	0.0579 (11)	0.0354 (9)	0.0082 (10)	−0.0026 (8)	−0.0025 (9)
C12	0.0612 (12)	0.0689 (13)	0.0414 (11)	−0.0038 (11)	0.0042 (9)	−0.0015 (10)
C13	0.0646 (14)	0.0930 (19)	0.0618 (15)	−0.0054 (14)	0.0073 (11)	0.0163 (13)
C14	0.0758 (17)	0.134 (3)	0.0436 (13)	0.0173 (19)	0.0148 (12)	0.0185 (15)
C15	0.102 (2)	0.128 (3)	0.0361 (12)	0.011 (2)	0.0057 (13)	−0.0111 (14)
C16	0.0779 (15)	0.0836 (16)	0.0425 (12)	0.0042 (14)	−0.0033 (10)	−0.0146 (11)
O3	0.0427 (7)	0.0408 (7)	0.0674 (9)	−0.0018 (6)	−0.0020 (6)	−0.0050 (7)
C17	0.0474 (13)	0.0563 (14)	0.135 (2)	−0.0051 (11)	−0.0158 (15)	−0.0056 (15)

Geometric parameters (Å, º)

Ni1—O2	2.0242 (12)	C8—H8	0.9300
Ni1—N2	2.0845 (15)	C9—C10	1.338 (3)
Ni1—O3	2.0970 (14)	C9—H9	0.9300
O1—C1	1.342 (2)	C10—C11	1.454 (3)
O1—H1	0.9512	C10—H10	0.9300
O2—C7	1.265 (2)	C11—C16	1.382 (3)
N1—C7	1.329 (2)	C11—C12	1.392 (3)
N1—N2	1.390 (2)	C12—C13	1.380 (3)
N2—C8	1.285 (2)	C12—H12	0.9300
C1—C6	1.393 (3)	C13—C14	1.369 (4)
C1—C2	1.415 (2)	C13—H13	0.9300
C2—C3	1.385 (3)	C14—C15	1.361 (5)
C2—C7	1.474 (2)	C14—H14	0.9300
C3—C4	1.378 (3)	C15—C16	1.377 (4)
C3—H3	0.9300	C15—H15	0.9300
C4—C5	1.380 (3)	C16—H16	0.9300
C4—H4	0.9300	O3—C17	1.395 (3)
C5—C6	1.368 (3)	O3—H18	0.9484
C5—H5	0.9300	C17—H17D	0.9600
C6—H6	0.9300	C17—H17A	0.9600
C8—C9	1.426 (3)	C17—H17B	0.9600
O2—Ni1—N2	78.80 (6)	C10—C9—C8	119.94 (18)
O2—Ni1—O3	90.48 (6)	C10—C9—H9	120.0
N2—Ni1—O3	90.30 (6)	C8—C9—H9	120.0
C1—O1—H1	103.6	C9—C10—C11	127.77 (19)
C7—O2—Ni1	112.29 (11)	C9—C10—H10	116.1
C7—N1—N2	114.11 (14)	C11—C10—H10	116.1
C8—N2—N1	114.08 (15)	C16—C11—C12	118.2 (2)
C8—N2—Ni1	135.45 (13)	C16—C11—C10	118.7 (2)
N1—N2—Ni1	110.37 (11)	C12—C11—C10	123.10 (18)
O1—C1—C6	119.52 (18)	C13—C12—C11	120.5 (2)
O1—C1—C2	121.69 (16)	C13—C12—H12	119.8
C6—C1—C2	118.78 (18)	C11—C12—H12	119.8
C3—C2—C1	119.02 (16)	C14—C13—C12	120.1 (3)
C3—C2—C7	119.02 (16)	C14—C13—H13	120.0
C1—C2—C7	121.95 (17)	C12—C13—H13	120.0
C4—C3—C2	121.24 (19)	C15—C14—C13	120.1 (2)
C4—C3—H3	119.4	C15—C14—H14	119.9
C2—C3—H3	119.4	C13—C14—H14	119.9
C3—C4—C5	119.4 (2)	C14—C15—C16	120.4 (2)
C3—C4—H4	120.3	C14—C15—H15	119.8
C5—C4—H4	120.3	C16—C15—H15	119.8
C6—C5—C4	120.87 (19)	C15—C16—C11	120.8 (3)
C6—C5—H5	119.6	C15—C16—H16	119.6
C4—C5—H5	119.6	C11—C16—H16	119.6
C5—C6—C1	120.67 (19)	C17—O3—Ni1	130.86 (13)
C5—C6—H6	119.7	C17—O3—H18	115.0
C1—C6—H6	119.7	Ni1—O3—H18	110.5
O2—C7—N1	123.73 (15)	O3—C17—H17D	109.5
O2—C7—C2	121.28 (16)	O3—C17—H17A	109.5
N1—C7—C2	114.97 (15)	H17D—C17—H17A	109.5
N2—C8—C9	124.18 (17)	O3—C17—H17B	109.5
N2—C8—H8	117.9	H17D—C17—H17B	109.5
C9—C8—H8	117.9	H17A—C17—H17B	109.5
N2^i—Ni1—O2—C7	−173.08 (12)	Ni1—O2—C7—C2	172.08 (12)
N2—Ni1—O2—C7	6.92 (12)	N2—N1—C7—O2	−0.3 (2)
O3^i—Ni1—O2—C7	96.72 (12)	N2—N1—C7—C2	−178.50 (14)
O3—Ni1—O2—C7	−83.28 (12)	C3—C2—C7—O2	2.7 (3)
C7—N1—N2—C8	−176.92 (16)	C1—C2—C7—O2	−175.99 (16)
C7—N1—N2—Ni1	6.16 (17)	C3—C2—C7—N1	−178.96 (16)
O2^i—Ni1—N2—C8	−2.94 (19)	C1—C2—C7—N1	2.3 (2)
O2—Ni1—N2—C8	177.06 (19)	N1—N2—C8—C9	177.06 (17)
O3^i—Ni1—N2—C8	87.49 (18)	Ni1—N2—C8—C9	−7.1 (3)
O3—Ni1—N2—C8	−92.51 (18)	N2—C8—C9—C10	−179.22 (18)
O2^i—Ni1—N2—N1	173.04 (11)	C8—C9—C10—C11	174.13 (19)
O2—Ni1—N2—N1	−6.96 (11)	C9—C10—C11—C16	173.6 (2)
O3^i—Ni1—N2—N1	−96.53 (11)	C9—C10—C11—C12	−8.3 (3)
O3—Ni1—N2—N1	83.47 (11)	C16—C11—C12—C13	−0.1 (3)
O1—C1—C2—C3	178.16 (17)	C10—C11—C12—C13	−178.2 (2)
C6—C1—C2—C3	−3.0 (3)	C11—C12—C13—C14	−0.4 (4)
O1—C1—C2—C7	−3.1 (3)	C12—C13—C14—C15	0.4 (4)
C6—C1—C2—C7	175.78 (17)	C13—C14—C15—C16	0.1 (5)
C1—C2—C3—C4	1.6 (3)	C14—C15—C16—C11	−0.7 (4)
C7—C2—C3—C4	−177.17 (18)	C12—C11—C16—C15	0.7 (4)
C2—C3—C4—C5	0.5 (3)	C10—C11—C16—C15	178.8 (2)
C3—C4—C5—C6	−1.2 (3)	O2^i—Ni1—O3—C17	−134.3 (2)
C4—C5—C6—C1	−0.2 (3)	O2—Ni1—O3—C17	45.7 (2)
O1—C1—C6—C5	−178.83 (18)	N2^i—Ni1—O3—C17	146.9 (2)
C2—C1—C6—C5	2.3 (3)	N2—Ni1—O3—C17	−33.1 (2)
Ni1—O2—C7—N1	−6.1 (2)

Symmetry code: (i) −x+1, −y, −z+1.

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1···N1	0.95	1.61	2.496 (2)	154
O3—H18···O1^ii	0.95	1.73	2.657 (2)	165

Symmetry code: (ii) x, y−1, z.

(II) bis[2-hydroxy-N'-(3-phenylprop-2-enylidene)benzohydrazidato- κ²N,O]bis(pyridine-κN)nickel(II)

Crystal data

[Ni(C16H13N2O2)2(C5H5N)2]	Z = 1
Mr = 747.48	F(000) = 390
Triclinic, P1	Dx = 1.384 Mg m^−3
a = 7.699 (6) Å	Mo Kα radiation, λ = 0.71073 Å
b = 9.814 (5) Å	Cell parameters from 4060 reflections
c = 12.412 (7) Å	θ = 3.1–27.7°
α = 78.02 (2)°	µ = 0.59 mm^−1
β = 82.59 (3)°	T = 293 K
γ = 79.00 (3)°	Prism, yellow
V = 896.6 (10) Å^3	0.20 × 0.20 × 0.11 mm

Data collection

Rigaku R-AXIS RAPID Imaging Plate diffractometer	3177 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	Rint = 0.041
Graphite monochromator	θmax = 27.7°, θmin = 3.1°
ω scans	h = −9→9
8839 measured reflections	k = −12→12
4060 independent reflections	l = −16→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)] = 0.042	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.100	H-atom parameters constrained
S = 1.00	w = 1/[σ^2(Fo^2) + (0.0493P)^2] where P = (Fo^2 + 2Fc^2)/3
4060 reflections	(Δ/σ)max = 0.001
241 parameters	Δρmax = 0.55 e Å^−3
0 restraints	Δρmin = −0.37 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.

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

	x	y	z	Uiso*/Ueq
Ni1	0.0000	0.5000	0.5000	0.03495 (12)
O1	0.3758 (2)	0.4223 (2)	0.85177 (14)	0.0728 (6)
H1	0.3680	0.4032	0.7787	0.109*
O2	−0.01315 (17)	0.59205 (13)	0.63258 (10)	0.0388 (3)
N1	0.2561 (2)	0.45066 (18)	0.66275 (12)	0.0413 (4)
N2	0.2449 (2)	0.41453 (16)	0.56100 (12)	0.0381 (4)
N3	0.1076 (2)	0.67528 (17)	0.39805 (13)	0.0401 (4)
C1	0.2408 (3)	0.5250 (2)	0.87246 (16)	0.0460 (5)
C2	0.1180 (3)	0.5882 (2)	0.79660 (15)	0.0381 (4)
C3	−0.0129 (3)	0.6954 (2)	0.82375 (17)	0.0507 (5)
H3	−0.0959	0.7395	0.7739	0.061*
C4	−0.0234 (4)	0.7387 (3)	0.9236 (2)	0.0615 (6)
H4	−0.1114	0.8127	0.9399	0.074*
C5	0.0957 (3)	0.6730 (3)	0.99868 (18)	0.0596 (6)
H5	0.0865	0.7006	1.0668	0.071*
C6	0.2266 (3)	0.5681 (3)	0.97415 (18)	0.0573 (6)
H6	0.3078	0.5243	1.0253	0.069*
C7	0.1173 (3)	0.54223 (18)	0.68994 (14)	0.0350 (4)
C8	0.3820 (3)	0.3312 (2)	0.52883 (17)	0.0457 (5)
H8	0.4744	0.3009	0.5742	0.055*
C9	0.3995 (3)	0.2824 (2)	0.42630 (16)	0.0445 (5)
H9	0.3130	0.3189	0.3773	0.053*
C10	0.5356 (3)	0.1865 (2)	0.39919 (18)	0.0532 (6)
H10	0.6177	0.1502	0.4511	0.064*
C11	0.5696 (3)	0.1319 (2)	0.29584 (18)	0.0472 (5)
C12	0.6757 (3)	0.0015 (3)	0.2947 (2)	0.0624 (7)
H12	0.7245	−0.0499	0.3587	0.075*
C13	0.7093 (4)	−0.0527 (3)	0.1968 (3)	0.0761 (8)
H13	0.7798	−0.1408	0.1962	0.091*
C14	0.6399 (4)	0.0223 (3)	0.1029 (2)	0.0736 (8)
H14	0.6629	−0.0143	0.0382	0.088*
C15	0.5367 (4)	0.1513 (3)	0.1035 (2)	0.0627 (7)
H15	0.4896	0.2027	0.0389	0.075*
C16	0.5015 (3)	0.2057 (2)	0.19881 (18)	0.0506 (5)
H16	0.4305	0.2939	0.1980	0.061*
C17	0.0723 (3)	0.8012 (2)	0.42732 (18)	0.0512 (5)
H17	0.0023	0.8104	0.4932	0.061*
C18	0.1335 (4)	0.9182 (2)	0.3656 (2)	0.0627 (7)
H18	0.1054	1.0039	0.3899	0.075*
C19	0.2366 (3)	0.9086 (2)	0.2677 (2)	0.0571 (6)
H19	0.2788	0.9869	0.2243	0.069*
C20	0.2748 (3)	0.7800 (2)	0.23638 (19)	0.0538 (5)
H20	0.3449	0.7688	0.1709	0.065*
C21	0.2088 (3)	0.6671 (2)	0.30252 (17)	0.0469 (5)
H21	0.2358	0.5803	0.2798	0.056*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Ni1	0.0415 (2)	0.03634 (19)	0.02703 (18)	−0.00144 (14)	−0.00781 (13)	−0.00795 (14)
O1	0.0700 (11)	0.0925 (13)	0.0543 (9)	0.0261 (10)	−0.0325 (8)	−0.0301 (10)
O2	0.0427 (8)	0.0420 (7)	0.0321 (6)	0.0011 (6)	−0.0106 (6)	−0.0107 (6)
N1	0.0454 (9)	0.0472 (9)	0.0335 (8)	0.0014 (7)	−0.0121 (7)	−0.0156 (8)
N2	0.0445 (9)	0.0400 (8)	0.0309 (8)	−0.0036 (7)	−0.0080 (7)	−0.0097 (7)
N3	0.0423 (9)	0.0421 (8)	0.0360 (8)	−0.0044 (7)	−0.0068 (7)	−0.0084 (7)
C1	0.0503 (12)	0.0528 (12)	0.0378 (10)	−0.0072 (10)	−0.0098 (9)	−0.0131 (10)
C2	0.0443 (11)	0.0405 (10)	0.0323 (9)	−0.0104 (8)	−0.0050 (8)	−0.0093 (8)
C3	0.0606 (14)	0.0500 (12)	0.0428 (11)	0.0005 (10)	−0.0120 (10)	−0.0163 (10)
C4	0.0728 (16)	0.0629 (14)	0.0518 (13)	−0.0002 (12)	−0.0046 (12)	−0.0287 (12)
C5	0.0718 (16)	0.0779 (16)	0.0384 (11)	−0.0186 (13)	−0.0023 (11)	−0.0283 (12)
C6	0.0636 (15)	0.0776 (16)	0.0361 (11)	−0.0148 (13)	−0.0176 (10)	−0.0123 (12)
C7	0.0442 (11)	0.0327 (9)	0.0292 (9)	−0.0091 (8)	−0.0059 (8)	−0.0048 (8)
C8	0.0422 (11)	0.0515 (11)	0.0447 (11)	0.0035 (9)	−0.0122 (9)	−0.0172 (10)
C9	0.0444 (11)	0.0480 (11)	0.0411 (11)	−0.0008 (9)	−0.0061 (9)	−0.0137 (9)
C10	0.0456 (12)	0.0632 (14)	0.0524 (12)	0.0061 (10)	−0.0134 (10)	−0.0226 (12)
C11	0.0374 (11)	0.0533 (12)	0.0538 (12)	−0.0049 (9)	0.0002 (9)	−0.0218 (11)
C12	0.0513 (14)	0.0619 (14)	0.0730 (16)	0.0073 (11)	−0.0064 (12)	−0.0256 (14)
C13	0.0639 (17)	0.0673 (16)	0.102 (2)	0.0033 (14)	0.0084 (16)	−0.0486 (18)
C14	0.0748 (18)	0.088 (2)	0.0684 (17)	−0.0220 (15)	0.0178 (15)	−0.0456 (17)
C15	0.0721 (16)	0.0718 (16)	0.0475 (13)	−0.0219 (13)	0.0076 (12)	−0.0175 (13)
C16	0.0565 (13)	0.0476 (11)	0.0481 (12)	−0.0123 (10)	0.0061 (10)	−0.0133 (10)
C17	0.0615 (14)	0.0427 (11)	0.0479 (12)	−0.0056 (10)	0.0016 (10)	−0.0122 (10)
C18	0.0795 (18)	0.0413 (11)	0.0657 (15)	−0.0089 (11)	−0.0006 (13)	−0.0112 (12)
C19	0.0574 (14)	0.0519 (12)	0.0588 (14)	−0.0162 (11)	−0.0063 (11)	0.0039 (11)
C20	0.0522 (13)	0.0605 (13)	0.0447 (12)	−0.0090 (11)	0.0008 (10)	−0.0045 (11)
C21	0.0548 (13)	0.0449 (11)	0.0390 (10)	−0.0056 (9)	−0.0018 (9)	−0.0077 (9)

Geometric parameters (Å, º)

Ni1—O2	2.0182 (15)	C9—C10	1.327 (3)
Ni1—N2	2.082 (2)	C9—H9	0.9300
Ni1—N3	2.1487 (19)	C10—C11	1.465 (3)
O1—C1	1.342 (3)	C10—H10	0.9300
O1—H1	0.9748	C11—C16	1.381 (3)
O2—C7	1.268 (2)	C11—C12	1.382 (3)
N1—C7	1.315 (2)	C12—C13	1.400 (3)
N1—N2	1.398 (2)	C12—H12	0.9300
N2—C8	1.280 (2)	C13—C14	1.357 (4)
N3—C17	1.329 (3)	C13—H13	0.9300
N3—C21	1.340 (2)	C14—C15	1.361 (4)
C1—C2	1.388 (3)	C14—H14	0.9300
C1—C6	1.397 (3)	C15—C16	1.373 (3)
C2—C3	1.375 (3)	C15—H15	0.9300
C2—C7	1.486 (2)	C16—H16	0.9300
C3—C4	1.380 (3)	C17—C18	1.369 (3)
C3—H3	0.9300	C17—H17	0.9300
C4—C5	1.367 (4)	C18—C19	1.373 (3)
C4—H4	0.9300	C18—H18	0.9300
C5—C6	1.350 (3)	C19—C20	1.365 (3)
C5—H5	0.9300	C19—H19	0.9300
C6—H6	0.9300	C20—C21	1.375 (3)
C8—C9	1.432 (3)	C20—H20	0.9300
C8—H8	0.9300	C21—H21	0.9300
O2—Ni1—N2	77.85 (6)	C8—C9—H9	119.0
O2—Ni1—N3	89.47 (7)	C9—C10—C11	126.6 (2)
N2—Ni1—N3	91.13 (8)	C9—C10—H10	116.7
C1—O1—H1	108.4	C11—C10—H10	116.7
C7—O2—Ni1	112.54 (10)	C16—C11—C12	118.32 (19)
C7—N1—N2	111.90 (15)	C16—C11—C10	122.83 (19)
C8—N2—N1	113.80 (16)	C12—C11—C10	118.8 (2)
C8—N2—Ni1	134.16 (13)	C11—C12—C13	119.7 (2)
N1—N2—Ni1	111.91 (11)	C11—C12—H12	120.1
C17—N3—C21	116.18 (19)	C13—C12—H12	120.1
C17—N3—Ni1	120.19 (14)	C14—C13—C12	120.5 (2)
C21—N3—Ni1	123.61 (14)	C14—C13—H13	119.7
O1—C1—C2	122.20 (17)	C12—C13—H13	119.7
O1—C1—C6	117.74 (19)	C13—C14—C15	119.9 (2)
C2—C1—C6	120.06 (19)	C13—C14—H14	120.0
C3—C2—C1	118.08 (17)	C15—C14—H14	120.0
C3—C2—C7	118.61 (17)	C14—C15—C16	120.3 (3)
C1—C2—C7	123.26 (16)	C14—C15—H15	119.8
C2—C3—C4	121.2 (2)	C16—C15—H15	119.8
C2—C3—H3	119.4	C15—C16—C11	121.2 (2)
C4—C3—H3	119.4	C15—C16—H16	119.4
C5—C4—C3	120.0 (2)	C11—C16—H16	119.4
C5—C4—H4	120.0	N3—C17—C18	123.5 (2)
C3—C4—H4	120.0	N3—C17—H17	118.3
C6—C5—C4	120.14 (19)	C18—C17—H17	118.3
C6—C5—H5	119.9	C17—C18—C19	119.8 (2)
C4—C5—H5	119.9	C17—C18—H18	120.1
C5—C6—C1	120.4 (2)	C19—C18—H18	120.1
C5—C6—H6	119.8	C20—C19—C18	117.6 (2)
C1—C6—H6	119.8	C20—C19—H19	121.2
O2—C7—N1	125.00 (15)	C18—C19—H19	121.2
O2—C7—C2	119.15 (15)	C19—C20—C21	119.4 (2)
N1—C7—C2	115.85 (16)	C19—C20—H20	120.3
N2—C8—C9	123.08 (19)	C21—C20—H20	120.3
N2—C8—H8	118.5	N3—C21—C20	123.53 (19)
C9—C8—H8	118.5	N3—C21—H21	118.2
C10—C9—C8	121.9 (2)	C20—C21—H21	118.2
C10—C9—H9	119.0
N2—Ni1—O2—C7	−7.23 (13)	C2—C1—C6—C5	−1.1 (4)
N2^i—Ni1—O2—C7	172.76 (13)	Ni1—O2—C7—N1	6.2 (2)
N3^i—Ni1—O2—C7	81.49 (14)	Ni1—O2—C7—C2	−173.76 (13)
N3—Ni1—O2—C7	−98.51 (14)	N2—N1—C7—O2	0.7 (3)
C7—N1—N2—C8	176.55 (18)	N2—N1—C7—C2	−179.41 (15)
C7—N1—N2—Ni1	−6.9 (2)	C3—C2—C7—O2	−7.3 (3)
O2—Ni1—N2—C8	−176.8 (2)	C1—C2—C7—O2	170.26 (19)
O2^i—Ni1—N2—C8	3.2 (2)	C3—C2—C7—N1	172.77 (18)
N3^i—Ni1—N2—C8	92.5 (2)	C1—C2—C7—N1	−9.7 (3)
N3—Ni1—N2—C8	−87.5 (2)	N1—N2—C8—C9	−179.14 (18)
O2—Ni1—N2—N1	7.63 (12)	Ni1—N2—C8—C9	5.3 (3)
O2^i—Ni1—N2—N1	−172.37 (12)	N2—C8—C9—C10	−174.0 (2)
N3^i—Ni1—N2—N1	−83.16 (13)	C8—C9—C10—C11	−178.2 (2)
N3—Ni1—N2—N1	96.84 (13)	C9—C10—C11—C16	23.3 (4)
O2—Ni1—N3—C17	−25.85 (16)	C9—C10—C11—C12	−157.3 (2)
O2^i—Ni1—N3—C17	154.15 (16)	C16—C11—C12—C13	−0.8 (4)
N2—Ni1—N3—C17	−103.69 (16)	C10—C11—C12—C13	179.8 (2)
N2^i—Ni1—N3—C17	76.31 (16)	C11—C12—C13—C14	0.6 (4)
O2—Ni1—N3—C21	155.48 (17)	C12—C13—C14—C15	−0.1 (4)
O2^i—Ni1—N3—C21	−24.52 (17)	C13—C14—C15—C16	−0.3 (4)
N2—Ni1—N3—C21	77.64 (17)	C14—C15—C16—C11	0.1 (4)
N2^i—Ni1—N3—C21	−102.36 (17)	C12—C11—C16—C15	0.4 (3)
O1—C1—C2—C3	−178.1 (2)	C10—C11—C16—C15	179.8 (2)
C6—C1—C2—C3	1.6 (3)	C21—N3—C17—C18	0.0 (3)
O1—C1—C2—C7	4.3 (3)	Ni1—N3—C17—C18	−178.8 (2)
C6—C1—C2—C7	−176.0 (2)	N3—C17—C18—C19	0.3 (4)
C1—C2—C3—C4	−0.4 (3)	C17—C18—C19—C20	−0.5 (4)
C7—C2—C3—C4	177.3 (2)	C18—C19—C20—C21	0.4 (4)
C2—C3—C4—C5	−1.3 (4)	C17—N3—C21—C20	0.0 (3)
C3—C4—C5—C6	1.8 (4)	Ni1—N3—C21—C20	178.74 (17)
C4—C5—C6—C1	−0.6 (4)	C19—C20—C21—N3	−0.2 (4)
O1—C1—C6—C5	178.6 (2)

Symmetry code: (i) −x, −y+1, −z+1.

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1···N1	0.97	1.71	2.573 (3)	146