Poly[bis­{μ-N′-[(pyridin-4-yl)methyl­idene]benzohydrazidato}copper(II)]

In the title complex, [Cu(C₁₃H₁₀N₃O)₂]_n, the copper(II) cation is located on a crystallographic inversion centre and adopts an elongated octa­hedral coordination geometry with the equatorial plane provided by trans-arranged bis-N,O-chelating acyl­hydrazine groups from two ligands and the apices by the N atoms of two pyridine rings belonging to symmetry-related ligands. The ligand adopts a Z conformation about the C=N double bond. The dihedral angle between the pyridine and phenyl rings is 2.99 (13)°. An intra­ligand C—H...N hydrogen bond is observed. In the crystal, each ligand bridges two adjacent metal ions, forming a (4,4) grid layered structure. π–π stacking inter­actions [centroid–centroid distances in the range 3.569 (4)–3.584 (9) Å] involving rings of adjacent layers result in the formation of a three-dimensional supra­molecular network.

Key indicators

• Single-crystal X-ray study
• T = 173 K
• Mean [sigma](C-C) = 0.003 Å
• R factor = 0.033
• wR factor = 0.080
• Data-to-parameter ratio = 15.4

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT910_ALERT_3_C Missing # of FCF Reflections Below Th(Min) .....          2

Alert level G
PLAT004_ALERT_5_G Info: Polymeric Structure Found with Dimension .          2
PLAT005_ALERT_5_G No _iucr_refine_instructions_details  in the CIF          ? Do !
PLAT232_ALERT_2_G Hirshfeld Test Diff (M-X)  Cu1    --  O1      ..        8.6 su
PLAT232_ALERT_2_G Hirshfeld Test Diff (M-X)  Cu1    --  N2      ..        7.0 su
PLAT794_ALERT_5_G Note: Tentative Bond Valency for Cu1     (II)          2.19
PLAT912_ALERT_4_G Missing # of FCF Reflections Above STh/L=  0.600          4

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

   0 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
   1 ALERT type 3 Indicator that the structure quality may be low
   1 ALERT type 4 Improvement, methodology, query or suggestion
   3 ALERT type 5 Informative message, check

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S1. Comment

Schiff bases and their metal compounds were widely synthesized in recent years and characterized for their wide range of applications as biocides and homogeneous catalysts in industry (Schurig et al., 1980; Siddall et al., 1983; Maurya et al., 2005). In previous reports, most of the Schiff base coordination compounds were oligomers such as zero-dimensional complexes with catalytic (Cozzi, 2004) or magnetic properties (Liu, et al., 2010). In this paper, the structure of a new two-dimensional polymeric copper(II) coordination compound is reported.

The asymmetric unit of the title complex contains one copper(II) ion located on an inversion centre and one deprotonated N'-(pyridin-4-ylmethyl) benzohydrazide ligand. The metal ion adopts a significantly elongated octahedral coordination geometry provided by four ligands (Fig. 1). The equatorial plane is occupied by two trans-arranged bis-N,O-chelating acylhydrazine groups from two ligands, while the axial positions are occupied by two N atoms of pyridine rings from other two ligands. In the equatorial plane, the Cu—O and Cu—N bond lengths are 1.942 (6) Å and 2.004 (4) Å, respectively, which are similar to those reported in the literature for related compounds (Yin 2008; Uçar et al., 2004; Sommerer et al., 1998). The apical Cu—N distances (2.578 (8) Å) are slightly longer than a common stretched Cu—N distance (Moya-Hernández et al., 2003), generating an elongated octahedral coordination geometry typically attributed to the Jahn-Teller effect. The ligand is approximately planar (maximum deviation from the least square plane is 0.0473 (13) Å for atom O1) and chelates to the copper atom to form a five-numbered ring (Cu1/O1/C7/N1/N2). The dihedral angle formed by the pyridine and phenyl rings is 2.99 (13)°. An intraligand C—H···N hydrogen bond is present (Table 1). In the crystal, each ligand bridges two adjacent metal ions (Fig. 2), meanwhile each copper atom is coordinated with four ligands to form a (4, 4) grid layered structure. Adjacent layers are further connected via π···π stacking interactions between benzene rings [Cg1···Cg1ⁱ =3.584 (9) Å; Cg1 is the centroid of the C1–C6 ring; symmetry code: (i) -1/2 - x, 1/2 - y, -z] and benzene and pyridine ring [Cg1···Cg2ⁱⁱ = 3.569 (4) Å; Cg2 is the centroid of the N1/C9–C13 ring; symmetry code: (ii) -x, -y, -z], forming a three-dimensional supramolecular structure (Fig. 3).

Related literature

For background to properties and applications of Schiff base–metal complexes, see: Schurig et al. (1980); Siddall et al. (1983); Maurya et al. (2005); Cozzi (2004); Liu, et al. (2010). For the structures of related compounds, see: Yin (2008); Uçar et al. (2004); Sommerer et al. (1998); Moya-Hernández et al. (2003).

S2. Experimental

A mixture of N'-(pyridin-4-ylmethyl)benzohydrazide (0.045 g, 0.02 mmol), Cu(CH₃COO)₂.4H₂O (0.026 g, 0.01 mmol) in ethanol (6 mL) was stirred for 40 minutes and then heated in a 25 mL Teflon-lined autoclave at 100°C for 3 days, followed by cooling to room temperature. The resulting mixture was washed with water, and brown crystals were collected and dried in air. Yield: 40% (based on Cu).

S3. Refinement

All H atoms were placed in idealized positions using a riding-model approximation, with C—H = 0.95 Å and U_iso(H) = 1.2U_eq(C).

Computing details

Data collection: CrystalClear (Rigaku, 2007); cell refinement: CrystalClear (Rigaku, 2007); data reduction: CrystalClear (Rigaku, 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: SHELXL97 (Sheldrick, 2008).

Figures

	Fig. 1. The molecular structure of the title compound with displacement ellipsoids drawn at the 30% probability level. H atoms are omitted for clarity. Symmetry codes: (i) 0.5 - x, 0.5 - y, -z; (ii) 0.5 - x, 0.5 + y, 0.5 - z; (iii) x, -y, -0.5 + z.
	Fig. 2. Capped sticks diagram of the two-dimensional grid in the title compound.
	Fig. 3. Packing diagram of the title compound, showing the π-π stacking interactions between phenyl rings (green dashed lines) or between phenyl and pyridine rings (red dashed lines). H atoms are omitted for clarity.

Poly[bis{µ-N'-[(pyridin-4-yl)methylidene]benzohydrazidato}copper(II)]

Crystal data

[Cu(C13H10N3O)2]	Z = 4
Mr = 512.02	F(000) = 1052
Monoclinic, C2/c	Dx = 1.586 Mg m^−3
Hall symbol: -C 2yc	Mo Kα radiation, λ = 0.71073 Å
a = 12.288 (3) Å	µ = 1.06 mm^−1
b = 13.349 (3) Å	T = 173 K
c = 14.244 (3) Å	Block, brown
β = 113.39 (3)°	0.40 × 0.20 × 0.12 mm
V = 2144.5 (10) Å^3

Data collection

Rigaku Mercury CCD area-detector diffractometer	2460 independent reflections
Radiation source: fine-focus sealed tube	2033 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.035
ω scan	θmax = 27.5°, θmin = 3.1°
Absorption correction: multi-scan (CrystalClear; Rigaku, 2007)	h = −15→15
Tmin = 0.843, Tmax = 1.000	k = −17→17
10356 measured reflections	l = −18→18

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)] = 0.033	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.080	H-atom parameters constrained
S = 1.05	w = 1/[σ^2(Fo^2) + (0.038P)^2 + 1.4497P] where P = (Fo^2 + 2Fc^2)/3
2460 reflections	(Δ/σ)max < 0.001
160 parameters	Δρmax = 0.33 e Å^−3
0 restraints	Δρmin = −0.19 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
Cu1	0.2500	0.2500	0.0000	0.03006 (12)
O1	0.07807 (11)	0.24346 (9)	−0.06638 (10)	0.0309 (3)
N3	0.27033 (14)	−0.10391 (12)	0.38950 (12)	0.0319 (4)
N2	0.21900 (13)	0.15245 (10)	0.09372 (11)	0.0246 (3)
N1	0.09996 (13)	0.13652 (11)	0.06875 (12)	0.0278 (3)
C13	0.38186 (16)	−0.00109 (14)	0.32256 (15)	0.0323 (4)
H13	0.4576	0.0211	0.3281	0.039*
C10	0.17175 (16)	0.00125 (14)	0.24281 (15)	0.0321 (4)
H10	0.0988	0.0242	0.1923	0.038*
C11	0.17304 (17)	−0.06719 (15)	0.31632 (15)	0.0346 (4)
H11	0.0988	−0.0896	0.3143	0.042*
C9	0.27962 (16)	0.03584 (13)	0.24435 (14)	0.0265 (4)
C7	0.03622 (16)	0.18736 (13)	−0.01562 (14)	0.0258 (4)
C12	0.37330 (17)	−0.06991 (15)	0.39198 (15)	0.0329 (4)
H12	0.4444	−0.0941	0.4440	0.039*
C1	−0.16555 (18)	0.23105 (14)	−0.13975 (16)	0.0339 (4)
H1	−0.1296	0.2705	−0.1751	0.041*
C6	−0.09470 (16)	0.17841 (13)	−0.05313 (14)	0.0278 (4)
C8	0.29530 (15)	0.10671 (13)	0.17138 (14)	0.0265 (4)
H8	0.3756	0.1211	0.1839	0.032*
C3	−0.34020 (18)	0.16951 (16)	−0.12463 (17)	0.0405 (5)
H3	−0.4241	0.1675	−0.1482	0.049*
C4	−0.27127 (19)	0.11491 (17)	−0.03975 (18)	0.0418 (5)
H4	−0.3079	0.0743	−0.0058	0.050*
C2	−0.28764 (18)	0.22705 (15)	−0.17542 (17)	0.0389 (5)
H2	−0.3352	0.2638	−0.2347	0.047*
C5	−0.14871 (17)	0.11890 (15)	−0.00365 (16)	0.0362 (4)
H5	−0.1015	0.0810	0.0549	0.043*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Cu1	0.02433 (17)	0.0392 (2)	0.02625 (18)	−0.00444 (14)	0.00965 (13)	0.01200 (14)
O1	0.0302 (6)	0.0357 (7)	0.0279 (7)	−0.0040 (6)	0.0128 (6)	0.0066 (5)
N3	0.0378 (9)	0.0309 (8)	0.0280 (9)	0.0025 (7)	0.0141 (7)	0.0053 (6)
N2	0.0270 (7)	0.0247 (7)	0.0247 (8)	−0.0015 (6)	0.0130 (6)	−0.0002 (6)
N1	0.0257 (7)	0.0301 (8)	0.0282 (8)	−0.0026 (6)	0.0113 (6)	0.0050 (6)
C13	0.0284 (9)	0.0358 (10)	0.0337 (11)	0.0008 (8)	0.0136 (8)	0.0044 (8)
C10	0.0285 (9)	0.0346 (9)	0.0307 (10)	0.0012 (8)	0.0090 (8)	0.0077 (8)
C11	0.0315 (10)	0.0369 (10)	0.0363 (11)	−0.0004 (8)	0.0144 (9)	0.0088 (8)
C9	0.0309 (9)	0.0235 (8)	0.0262 (9)	0.0025 (7)	0.0125 (8)	0.0013 (7)
C7	0.0314 (9)	0.0238 (8)	0.0247 (9)	−0.0023 (7)	0.0139 (8)	−0.0017 (7)
C12	0.0320 (9)	0.0353 (10)	0.0289 (10)	0.0065 (8)	0.0094 (8)	0.0072 (8)
C1	0.0352 (10)	0.0333 (10)	0.0337 (11)	−0.0001 (8)	0.0143 (9)	0.0064 (8)
C6	0.0308 (9)	0.0272 (9)	0.0276 (10)	−0.0028 (7)	0.0139 (8)	−0.0006 (7)
C8	0.0279 (9)	0.0265 (8)	0.0272 (9)	0.0003 (7)	0.0133 (8)	0.0017 (7)
C3	0.0301 (10)	0.0448 (12)	0.0471 (13)	−0.0040 (9)	0.0159 (9)	−0.0033 (9)
C4	0.0391 (11)	0.0462 (12)	0.0455 (12)	−0.0106 (10)	0.0227 (10)	0.0031 (10)
C2	0.0340 (10)	0.0396 (11)	0.0382 (12)	0.0031 (9)	0.0092 (9)	0.0068 (8)
C5	0.0350 (10)	0.0402 (11)	0.0339 (11)	−0.0026 (9)	0.0141 (9)	0.0080 (8)

Geometric parameters (Å, º)

Cu1—O1^i	1.9440 (15)	C11—H11	0.9500
Cu1—O1	1.9440 (15)	C9—C8	1.474 (2)
Cu1—N2^i	2.0066 (14)	C7—C6	1.485 (2)
Cu1—N2	2.0066 (14)	C12—H12	0.9500
O1—C7	1.282 (2)	C1—C2	1.381 (3)
N3—C11	1.329 (2)	C1—C6	1.386 (3)
N3—C12	1.331 (2)	C1—H1	0.9500
N2—C8	1.285 (2)	C6—C5	1.393 (3)
N2—N1	1.378 (2)	C8—H8	0.9500
N1—C7	1.331 (2)	C3—C4	1.377 (3)
C13—C12	1.384 (3)	C3—C2	1.379 (3)
C13—C9	1.397 (3)	C3—H3	0.9500
C13—H13	0.9500	C4—C5	1.386 (3)
C10—C11	1.385 (3)	C4—H4	0.9500
C10—C9	1.395 (3)	C2—H2	0.9500
C10—H10	0.9500	C5—H5	0.9500
O1^i—Cu1—O1	180.0	N1—C7—C6	116.68 (15)
O1^i—Cu1—N2^i	80.66 (6)	N3—C12—C13	123.25 (18)
O1—Cu1—N2^i	99.34 (6)	N3—C12—H12	118.4
O1^i—Cu1—N2	99.34 (6)	C13—C12—H12	118.4
O1—Cu1—N2	80.66 (6)	C2—C1—C6	120.98 (18)
N2^i—Cu1—N2	180.00 (8)	C2—C1—H1	119.5
C7—O1—Cu1	110.72 (12)	C6—C1—H1	119.5
C11—N3—C12	116.40 (16)	C1—C6—C5	118.85 (17)
C8—N2—N1	119.06 (15)	C1—C6—C7	119.16 (16)
C8—N2—Cu1	127.92 (12)	C5—C6—C7	121.98 (17)
N1—N2—Cu1	113.01 (11)	N2—C8—C9	131.08 (16)
C7—N1—N2	109.77 (14)	N2—C8—H8	114.5
C12—C13—C9	120.31 (18)	C9—C8—H8	114.5
C12—C13—H13	119.8	C4—C3—C2	120.16 (19)
C9—C13—H13	119.8	C4—C3—H3	119.9
C11—C10—C9	118.73 (18)	C2—C3—H3	119.9
C11—C10—H10	120.6	C3—C4—C5	120.28 (19)
C9—C10—H10	120.6	C3—C4—H4	119.9
N3—C11—C10	124.95 (18)	C5—C4—H4	119.9
N3—C11—H11	117.5	C3—C2—C1	119.68 (19)
C10—C11—H11	117.5	C3—C2—H2	120.2
C10—C9—C13	116.34 (17)	C1—C2—H2	120.2
C10—C9—C8	126.20 (17)	C4—C5—C6	120.01 (19)
C13—C9—C8	117.45 (16)	C4—C5—H5	120.0
O1—C7—N1	125.68 (16)	C6—C5—H5	120.0
O1—C7—C6	117.64 (16)
N2^i—Cu1—O1—C7	−176.85 (12)	C11—N3—C12—C13	−0.8 (3)
N2—Cu1—O1—C7	3.15 (12)	C9—C13—C12—N3	−0.5 (3)
O1^i—Cu1—N2—C8	−2.68 (16)	C2—C1—C6—C5	1.6 (3)
O1—Cu1—N2—C8	177.32 (16)	C2—C1—C6—C7	−178.12 (18)
O1^i—Cu1—N2—N1	176.46 (11)	O1—C7—C6—C1	−0.6 (3)
O1—Cu1—N2—N1	−3.54 (11)	N1—C7—C6—C1	178.95 (17)
C8—N2—N1—C7	−177.64 (15)	O1—C7—C6—C5	179.64 (17)
Cu1—N2—N1—C7	3.13 (17)	N1—C7—C6—C5	−0.8 (3)
C12—N3—C11—C10	1.3 (3)	N1—N2—C8—C9	−0.2 (3)
C9—C10—C11—N3	−0.3 (3)	Cu1—N2—C8—C9	178.87 (14)
C11—C10—C9—C13	−1.0 (3)	C10—C9—C8—N2	0.8 (3)
C11—C10—C9—C8	178.68 (18)	C13—C9—C8—N2	−179.51 (18)
C12—C13—C9—C10	1.4 (3)	C2—C3—C4—C5	1.2 (3)
C12—C13—C9—C8	−178.30 (17)	C4—C3—C2—C1	−1.1 (3)
Cu1—O1—C7—N1	−2.6 (2)	C6—C1—C2—C3	−0.3 (3)
Cu1—O1—C7—C6	176.93 (12)	C3—C4—C5—C6	0.1 (3)
N2—N1—C7—O1	−0.4 (2)	C1—C6—C5—C4	−1.5 (3)
N2—N1—C7—C6	−179.92 (14)	C7—C6—C5—C4	178.24 (19)

Symmetry code: (i) −x+1/2, −y+1/2, −z.

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
C10—H10···N1	0.95	2.32	2.907 (3)	120