Diaqua­bis­{2-hy­droxy-5-[(pyridin-2-yl)methyl­idene­amino]­benzoato-κ2N,N′}zinc(II) dihydrate

Bing, Y.; Li, X.; Zha, M.; Lu, Y.

doi:10.1107/S160053681004496X

metal-organic compounds

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ISSN: 2056-9890

Volume 66| Part 12| December 2010| Pages m1524-m1525

https://doi.org/10.1107/S160053681004496X

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Diaquabis{2-hydroxy-5-[(pyridin-2-yl)methylideneamino]benzoato-κ²N,N′}zinc(II) dihydrate

Yue Bing,^a Xing Li,^a ^* Meiqin Zha ^a and Yue Lu ^a

^aFaculty of Materials Science and Chemical Engineering, Ningbo University, Ningbo, Zhejiang 315211, People's Republic of China
^*Correspondence e-mail: lix905@126.com

(Received 28 October 2010; accepted 2 November 2010; online 6 November 2010)

The complex molecule of the title compound, [Zn(C₁₃H₉N₂O₃)₂(H₂O)₂]·2H₂O, has 2 symmetry with the Zn^II cation located on a twofold rotation axis. The Zn cation is N,N′-chelated by two 5-[(pyridin-2-yl)methylideneamino]-2-hydroxybenzoate anions and coordinated by two water molecules in a distorted octahedral geometry. Within the anionic ligand, the pyridine ring is oriented at a dihedral angle of 49.54 (10)° with respect to the benzene ring. The carboxylate group of the anionic ligand is not involved in coordination but is O—H⋯O hydrogen bonded to the coordinated and uncoordinated water molecules. Weak intermolecular C—H⋯O hydrogen bonding is also present in the crystal structure.

Related literature

The title compound is a Schiff base complex; for potential applications of Schiff base compounds, see: Bourque et al. (2005 ); Donald & Osit (2010 ); Feng et al. (2007 ); Gang et al. (2007 ); Shanta et al. (2003 ).

Experimental

Crystal data

[Zn(C₁₃H₉N₂O₃)₂(H₂O)₂]·2H₂O
M_r = 619.90
Orthorhombic, P b c n
a = 15.812 (2) Å
b = 10.6962 (15) Å
c = 15.636 (2) Å
V = 2644.5 (6) Å³
Z = 4
Mo Kα radiation
μ = 1.00 mm⁻¹
T = 296 K
0.43 × 0.32 × 0.27 mm

Data collection

Bruker SMART APEX CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2001 ) T_min = 0.689, T_max = 0.764
21797 measured reflections
3041 independent reflections
2291 reflections with I > 2σ(I)
R_int = 0.038

Refinement

R[F² > 2σ(F²)] = 0.030
wR(F²) = 0.083
S = 1.03
3041 reflections
206 parameters
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.33 e Å⁻³
Δρ_min = −0.29 e Å⁻³

Table 1
Selected bond lengths (Å)

Zn1—O1	2.0471 (15)
Zn1—N1	2.1414 (17)
Zn1—N2	2.2746 (14)

Table 2
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O1—H1⋯O4ⁱ	0.80 (3)	1.83 (3)	2.618 (2)	169 (3)
O1—H2⋯O5	0.84 (3)	1.90 (3)	2.744 (3)	178 (3)
O5—H3⋯O3ⁱⁱ	0.86 (3)	1.98 (3)	2.808 (2)	161 (3)
O5—H4⋯O2ⁱⁱⁱ	0.83 (3)	2.05 (3)	2.881 (3)	174 (3)
O2—H5⋯O3	0.95 (3)	1.58 (3)	2.473 (2)	156 (3)
C6—H6A⋯O2ⁱⁱ	0.93	2.57	3.346 (3)	142
Symmetry codes: (i) x, y+1, z; (ii) -x+1, -y, -z; (iii) $[x-{\script{1\over 2}}, -y+{\script{1\over 2}}, -z]$ .

Data collection: SMART (Bruker, 2001); cell refinement: SAINT (Bruker, 2001); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008 ); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL.

Supporting information

Crystal structure: contains datablocks I, global. DOI: https://doi.org/10.1107/S160053681004496X/xu5074sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S160053681004496X/xu5074Isup2.hkl

checkCIF report

Comment top

The current interest in design and synthesis of new Schiff bases and their metal complexes stem from their potential applications in antimicrobial (Bourque et al., 2005), magnetic (Feng et al., 2007; Gang et al., 2007), anticancer (Shanta et al., 2003) and catalytic (Donald et al., 2010). Hereby design and synthesis of new Schiff bases is a important field in coordination chemistry. 5-aminosalicylic acid is widely used in medicine and dye chemistry. 2-pyridinecarboxaldehyde is the intermeadiate of the bisacodyl, which is a popular medicine. We synthesized a new Schiff base 5-((pyridin-2-yl)methyleneamino)-2-hydroxybenzoic acid (C₁₃H₉N₂O₃) from 5-aminosalicylic acid and 2-pyridinecarboxaldehyde by nucleophilic addition, followed by a dehydration. The Schiff base can coordinate to the metal atoms through N or O donor atoms. Herein we report the preparation and characterization of the first 5-((pyridin-2-yl)methyleneamino)-2-hydroxybenzoic-zinc(II) complex, [Zn(C₁₃H₉N₂O₃)₂(H₂O)₂].2H₂O.

Single-crystal X-ray diffraction analysis indicates the title complex possesses a mononuclear structure and crystallizes in the orthorhombic, space group Pbcn with Z = 4. The asymmetric unit consists of two Schiff base ligand, one zinc ion, two coordinated water and two guest water molecule. A view of the zinc ion coordination is shown in Figure 1, where the metal center is coordinated in an octahedral geometry by four N atoms of the Schiff base ligand with Zn—N distances ranging from 2.1416 (17) to 2.2742 (14) Å and two O atoms from water molecules with Zn—O distances ranging from 2.0491 (15) Å. The intromolecular interaction is helpful to the stabilization of the crystal structure (Figure 2).

Related literature top

The title compound is a Schiff base complex; for potential applications of Schiff base compounds, see: Bourque et al. (2005); Donald & Osit (2010); Feng et al. (2007); Gang et al. (2007); Shanta et al. (2003).

Experimental top

5-Aminosalicylic acid (1.53 g, 10 mmol), 2-pyridinecarboxaldehyde (1 ml, 10 mmol) and triethylamine (1 ml, 10 mmol) were added to 50 ml e thanol in a round flask, and this mixture was refluxed with agitation for 4 h at 323 K to give an yellow precipitate. After filtration and washing the precipitate with ethanol to give the pure Schiff base 5-((pyridin-2-yl)methyleneamino)-2-hydroxybenzoic acid (2.02 g, 84.00%).

Mixture of 5-((pyridin-2-yl)methyleneamino)-2-hydroxybenzoic acid (0.1 mmol, 0.024 g), Zn(OAc)₂.2H₂O (0.1 mmol, 0.022 g) and methanol (20 ml) to give an yellow solution. After evaporating the solution for one week, yellow crystals were obtained (yield, 50%).

Structure description top

The title compound is a Schiff base complex; for potential applications of Schiff base compounds, see: Bourque et al. (2005); Donald & Osit (2010); Feng et al. (2007); Gang et al. (2007); Shanta et al. (2003).

Computing details top

Data collection: SMART (Bruker, 2001); cell refinement: SAINT (Bruker, 2001); data reduction: SAINT (Bruker, 2001); 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 top

	Fig. 1. A view of the zinc ion coordination, showing the labeling of the non-H atoms and 30% probability ellipsoids. H atoms have been omitted for clarity.
	Fig. 2. Packing of title complex showing the three dimensional hydrogen bonding network.

Diaquabis{2-hydroxy-5-[(pyridin-2-yl)methylideneamino]benzoato- κ²N,N'}zinc(II) dihydrate top

Crystal data top

[Zn(C₁₃H₉N₂O₃)₂(H₂O)₂]·2H₂O	F(000) = 1280
M_r = 619.90	D_x = 1.557 Mg m⁻³
Orthorhombic, Pbcn	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2n 2ab	Cell parameters from 5445 reflections
a = 15.812 (2) Å	θ = 2.3–26.5°
b = 10.6962 (15) Å	µ = 1.00 mm⁻¹
c = 15.636 (2) Å	T = 296 K
V = 2644.5 (6) Å³	Block, yellow
Z = 4	0.43 × 0.32 × 0.27 mm

Data collection top

Bruker SMART APEX CCD area-detector diffractometer	3041 independent reflections
Radiation source: fine-focus sealed tube	2291 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.038
φ and ω scans	θ_max = 27.5°, θ_min = 2.3°
Absorption correction: multi-scan (SADABS; Bruker, 2001)	h = −20→20
T_min = 0.689, T_max = 0.764	k = −13→13
21797 measured reflections	l = −20→20

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)] = 0.030	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.083	H atoms treated by a mixture of independent and constrained refinement
S = 1.03	w = 1/[σ²(F_o²) + (0.0389P)² + 0.7619P] where P = (F_o² + 2F_c²)/3
3041 reflections	(Δ/σ)_max < 0.001
206 parameters	Δρ_max = 0.33 e Å⁻³
0 restraints	Δρ_min = −0.29 e Å⁻³

Crystal data top

[Zn(C₁₃H₉N₂O₃)₂(H₂O)₂]·2H₂O	V = 2644.5 (6) Å³
M_r = 619.90	Z = 4
Orthorhombic, Pbcn	Mo Kα radiation
a = 15.812 (2) Å	µ = 1.00 mm⁻¹
b = 10.6962 (15) Å	T = 296 K
c = 15.636 (2) Å	0.43 × 0.32 × 0.27 mm

Data collection top

Bruker SMART APEX CCD area-detector diffractometer	3041 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2001)	2291 reflections with I > 2σ(I)
T_min = 0.689, T_max = 0.764	R_int = 0.038
21797 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.030	0 restraints
wR(F²) = 0.083	H atoms treated by a mixture of independent and constrained refinement
S = 1.03	Δρ_max = 0.33 e Å⁻³
3041 reflections	Δρ_min = −0.29 e Å⁻³
206 parameters

Special details top

Experimental. IR (KBr, cm-1): 3455(versus), 3088(w), 2924(w), 2361(w), 1919(w), 1668(s), 1602(m), 1578(m), 1489(versus), 1447(m), 1364(versus), 1299(m), 1245(s), 1161(m), 1084(m), 1054(s), 959(w), 893(m), 839(s), 792(versus), 655(m), 572(m), 512(m).

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
Zn1	0.5000	0.40959 (2)	0.2500	0.03779 (10)
O1	0.49550 (12)	0.53276 (14)	0.14990 (11)	0.0590 (4)
O2	0.70387 (10)	−0.06373 (16)	−0.00402 (11)	0.0623 (4)
O3	0.62843 (10)	−0.24718 (13)	0.05467 (11)	0.0670 (4)
O4	0.51579 (10)	−0.22474 (13)	0.13984 (11)	0.0615 (4)
O5	0.37521 (14)	0.47962 (17)	0.02876 (13)	0.0709 (5)
N1	0.36496 (10)	0.39448 (14)	0.24957 (9)	0.0414 (4)
N2	0.47286 (10)	0.24704 (13)	0.16032 (9)	0.0364 (3)
C1	0.31145 (14)	0.4780 (2)	0.28233 (14)	0.0525 (5)
H1A	0.3329	0.5440	0.3144	0.063*
C2	0.22455 (15)	0.4697 (2)	0.27010 (15)	0.0625 (6)
H2A	0.1889	0.5311	0.2919	0.075*
C3	0.19182 (15)	0.3703 (2)	0.22564 (16)	0.0643 (6)
H3A	0.1337	0.3615	0.2190	0.077*
C4	0.24669 (13)	0.2838 (2)	0.19101 (14)	0.0537 (5)
H4A	0.2262	0.2158	0.1603	0.064*
C5	0.33299 (12)	0.30015 (17)	0.20284 (12)	0.0416 (4)
C6	0.39452 (12)	0.21815 (16)	0.16127 (12)	0.0415 (4)
H6A	0.3765	0.1445	0.1354	0.050*
C7	0.53077 (12)	0.16496 (16)	0.11906 (11)	0.0363 (4)
C8	0.59723 (12)	0.21657 (17)	0.07233 (12)	0.0458 (4)
H8A	0.6034	0.3029	0.0695	0.055*
C9	0.65391 (13)	0.14022 (19)	0.03025 (13)	0.0507 (5)
H9A	0.6977	0.1753	−0.0014	0.061*
C10	0.64583 (12)	0.01035 (18)	0.03502 (13)	0.0444 (4)
C11	0.57989 (11)	−0.04244 (16)	0.08294 (12)	0.0386 (4)
C12	0.52303 (11)	0.03585 (16)	0.12417 (11)	0.0374 (4)
H12A	0.4790	0.0013	0.1558	0.045*
C13	0.57306 (13)	−0.18215 (17)	0.09375 (13)	0.0470 (5)
H1	0.5058 (16)	0.606 (3)	0.152 (2)	0.081 (10)*
H2	0.4595 (18)	0.517 (3)	0.1115 (18)	0.083 (9)*
H3	0.3812 (19)	0.417 (3)	−0.005 (2)	0.084 (9)*
H4	0.326 (2)	0.507 (3)	0.025 (2)	0.124 (14)*
H5	0.685 (2)	−0.146 (3)	0.009 (2)	0.117 (11)*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Zn1	0.04294 (17)	0.02329 (15)	0.04715 (18)	0.000	−0.00043 (13)	0.000
O1	0.0828 (11)	0.0317 (8)	0.0625 (9)	−0.0157 (8)	−0.0203 (9)	0.0127 (7)
O2	0.0562 (9)	0.0523 (9)	0.0785 (11)	−0.0026 (7)	0.0186 (8)	−0.0231 (8)
O3	0.0642 (9)	0.0356 (8)	0.1011 (12)	0.0057 (7)	0.0064 (9)	−0.0178 (8)
O4	0.0744 (11)	0.0280 (7)	0.0820 (11)	−0.0052 (7)	0.0102 (8)	0.0028 (7)
O5	0.0746 (12)	0.0529 (10)	0.0851 (12)	0.0051 (9)	−0.0225 (10)	−0.0171 (9)
N1	0.0442 (8)	0.0357 (8)	0.0443 (8)	0.0064 (6)	0.0028 (7)	0.0041 (7)
N2	0.0446 (8)	0.0241 (7)	0.0406 (8)	0.0009 (6)	0.0000 (6)	0.0006 (6)
C1	0.0608 (13)	0.0453 (12)	0.0514 (11)	0.0133 (10)	0.0115 (10)	0.0046 (9)
C2	0.0562 (13)	0.0630 (15)	0.0684 (15)	0.0221 (11)	0.0210 (11)	0.0172 (12)
C3	0.0452 (12)	0.0712 (16)	0.0764 (15)	0.0103 (11)	0.0067 (11)	0.0232 (13)
C4	0.0462 (11)	0.0533 (12)	0.0616 (13)	−0.0023 (9)	−0.0050 (10)	0.0108 (10)
C5	0.0427 (10)	0.0356 (9)	0.0466 (10)	0.0005 (8)	−0.0012 (8)	0.0081 (8)
C6	0.0466 (11)	0.0302 (9)	0.0477 (10)	−0.0031 (8)	−0.0059 (8)	−0.0008 (8)
C7	0.0402 (9)	0.0283 (9)	0.0404 (9)	−0.0013 (7)	−0.0009 (8)	−0.0014 (7)
C8	0.0593 (12)	0.0284 (9)	0.0497 (10)	−0.0078 (8)	0.0067 (9)	−0.0001 (8)
C9	0.0572 (12)	0.0423 (11)	0.0525 (11)	−0.0125 (9)	0.0166 (10)	−0.0025 (9)
C10	0.0457 (10)	0.0416 (10)	0.0459 (10)	−0.0015 (8)	0.0015 (9)	−0.0118 (8)
C11	0.0429 (10)	0.0285 (8)	0.0443 (10)	−0.0031 (7)	−0.0054 (8)	−0.0039 (7)
C12	0.0394 (9)	0.0290 (9)	0.0438 (10)	−0.0047 (7)	−0.0017 (7)	0.0000 (7)
C13	0.0533 (12)	0.0284 (9)	0.0593 (12)	0.0014 (8)	−0.0092 (10)	−0.0067 (9)

Geometric parameters (Å, º) top

Zn1—O1ⁱ	2.0471 (15)	C1—H1A	0.9300
Zn1—O1	2.0471 (15)	C2—C3	1.372 (4)
Zn1—N1ⁱ	2.1414 (17)	C2—H2A	0.9300
Zn1—N1	2.1414 (17)	C3—C4	1.379 (3)
Zn1—N2	2.2746 (14)	C3—H3A	0.9300
Zn1—N2ⁱ	2.2746 (14)	C4—C5	1.388 (3)
O1—H1	0.81 (3)	C4—H4A	0.9300
O1—H2	0.84 (3)	C5—C6	1.462 (3)
O2—C10	1.357 (2)	C6—H6A	0.9300
O2—H5	0.95 (3)	C7—C12	1.389 (2)
O3—C13	1.274 (2)	C7—C8	1.394 (3)
O4—C13	1.244 (2)	C8—C9	1.380 (3)
O5—H3	0.86 (3)	C8—H8A	0.9300
O5—H4	0.84 (4)	C9—C10	1.397 (3)
N1—C1	1.333 (2)	C9—H9A	0.9300
N1—C5	1.344 (2)	C10—C11	1.403 (3)
N2—C6	1.277 (2)	C11—C12	1.388 (2)
N2—C7	1.423 (2)	C11—C13	1.508 (2)
C1—C2	1.390 (3)	C12—H12A	0.9300

O1ⁱ—Zn1—O1	99.88 (10)	C2—C3—H3A	120.6
O1ⁱ—Zn1—N1ⁱ	90.66 (6)	C4—C3—H3A	120.6
O1—Zn1—N1ⁱ	94.92 (7)	C3—C4—C5	118.8 (2)
O1ⁱ—Zn1—N1	94.92 (7)	C3—C4—H4A	120.6
O1—Zn1—N1	90.66 (6)	C5—C4—H4A	120.6
N1ⁱ—Zn1—N1	171.34 (8)	N1—C5—C4	122.45 (18)
O1ⁱ—Zn1—N2	165.91 (6)	N1—C5—C6	116.20 (16)
O1—Zn1—N2	90.80 (6)	C4—C5—C6	121.29 (18)
N1ⁱ—Zn1—N2	97.61 (5)	N2—C6—C5	120.37 (16)
N1—Zn1—N2	75.65 (6)	N2—C6—H6A	119.8
O1ⁱ—Zn1—N2ⁱ	90.80 (6)	C5—C6—H6A	119.8
O1—Zn1—N2ⁱ	165.91 (6)	C12—C7—C8	119.37 (17)
N1ⁱ—Zn1—N2ⁱ	75.65 (6)	C12—C7—N2	122.05 (16)
N1—Zn1—N2ⁱ	97.61 (5)	C8—C7—N2	118.58 (15)
N2—Zn1—N2ⁱ	80.29 (7)	C9—C8—C7	120.36 (17)
Zn1—O1—H1	126 (2)	C9—C8—H8A	119.8
Zn1—O1—H2	115.9 (19)	C7—C8—H8A	119.8
H1—O1—H2	111 (3)	C8—C9—C10	120.25 (17)
C10—O2—H5	103 (2)	C8—C9—H9A	119.9
H3—O5—H4	109 (3)	C10—C9—H9A	119.9
C1—N1—C5	118.25 (18)	O2—C10—C9	119.64 (18)
C1—N1—Zn1	125.53 (15)	O2—C10—C11	120.52 (18)
C5—N1—Zn1	115.68 (12)	C9—C10—C11	119.79 (17)
C6—N2—C7	118.70 (15)	C12—C11—C10	119.14 (16)
C6—N2—Zn1	111.15 (12)	C12—C11—C13	119.98 (17)
C7—N2—Zn1	129.02 (12)	C10—C11—C13	120.80 (17)
N1—C1—C2	122.1 (2)	C11—C12—C7	121.09 (17)
N1—C1—H1A	118.9	C11—C12—H12A	119.5
C2—C1—H1A	118.9	C7—C12—H12A	119.5
C3—C2—C1	119.5 (2)	O4—C13—O3	125.32 (18)
C3—C2—H2A	120.3	O4—C13—C11	118.69 (17)
C1—C2—H2A	120.3	O3—C13—C11	115.98 (18)
C2—C3—C4	118.8 (2)

Symmetry code: (i) −x+1, y, −z+1/2.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1···O4ⁱⁱ	0.80 (3)	1.83 (3)	2.618 (2)	169 (3)
O1—H2···O5	0.84 (3)	1.90 (3)	2.744 (3)	178 (3)
O5—H3···O3ⁱⁱⁱ	0.86 (3)	1.98 (3)	2.808 (2)	161 (3)
O5—H4···O2^iv	0.83 (3)	2.05 (3)	2.881 (3)	174 (3)
O2—H5···O3	0.95 (3)	1.58 (3)	2.473 (2)	156 (3)
C6—H6A···O2ⁱⁱⁱ	0.93	2.57	3.346 (3)	142

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

Experimental details

Crystal data
Chemical formula	[Zn(C₁₃H₉N₂O₃)₂(H₂O)₂]·2H₂O
M_r	619.90
Crystal system, space group	Orthorhombic, Pbcn
Temperature (K)	296
a, b, c (Å)	15.812 (2), 10.6962 (15), 15.636 (2)
V (Å³)	2644.5 (6)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	1.00
Crystal size (mm)	0.43 × 0.32 × 0.27

Data collection
Diffractometer	Bruker SMART APEX CCD area-detector
Absorption correction	Multi-scan (SADABS; Bruker, 2001)
T_min, T_max	0.689, 0.764
No. of measured, independent and observed [I > 2σ(I)] reflections	21797, 3041, 2291
R_int	0.038
(sin θ/λ)_max (Å⁻¹)	0.649

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.030, 0.083, 1.03
No. of reflections	3041
No. of parameters	206
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.33, −0.29

Computer programs: SMART (Bruker, 2001), SAINT (Bruker, 2001), SHELXTL (Sheldrick, 2008).

Selected bond lengths (Å) top

Zn1—O1	2.0471 (15)	Zn1—N2	2.2746 (14)
Zn1—N1	2.1414 (17)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1···O4ⁱ	0.80 (3)	1.83 (3)	2.618 (2)	169 (3)
O1—H2···O5	0.84 (3)	1.90 (3)	2.744 (3)	178 (3)
O5—H3···O3ⁱⁱ	0.86 (3)	1.98 (3)	2.808 (2)	161 (3)
O5—H4···O2ⁱⁱⁱ	0.83 (3)	2.05 (3)	2.881 (3)	174 (3)
O2—H5···O3	0.95 (3)	1.58 (3)	2.473 (2)	156 (3)
C6—H6A···O2ⁱⁱ	0.93	2.57	3.346 (3)	142

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

Acknowledgements

The work was supported by the Ningbo Natural Science Foundation (2010 A610060), the `Qianjiang Talent' Projects of Zhejiang Province (2009R10032), the Ningbo University Foundation (XK1066), the Program for Innovative Research Team of Ningbo Novel Photoelectric Materials and Devices (2009B21007) and the K. C. Wong Magna Fund of Ningbo University.

References

Bourque, T. A., Nelles, M. E., Gullon, T. J., Garon, C. N., Ringer, M. K., Leger, L. J., Mason, J. W., Wheaton, S. L., Baerlocher, F. J., Vogels, C. M., Decken, A. & Westcott, S. A. (2005). Can. J. Chem. 83, 1063–1070. Web of Science CSD CrossRef CAS Google Scholar
Bruker (2001). SAINT, SMART and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA. Google Scholar
Donald, J. D. & Osit, K. (2010). Inorg. Chem. 49, 2360–2371. Web of Science PubMed Google Scholar
Feng, L., Ji, Z. & Mohamedally, K. (2007). Inorg. Chem. 46, 8448–8450. Web of Science CSD CrossRef PubMed Google Scholar
Gang, W., Ian, J. H., Samir, M., Yanhua, L., Rodolphe, C., Christopher, E. A., Shilun, Q. & Annie, K. P. (2007). Inorg. Chem. 46, 7229–7231. Web of Science PubMed Google Scholar
Shanta, D., Dulal, S., Puspendu, K. D., Pabitra, C., Munirathinam, N. & Akhil, R. C. (2003). J. Am. Chem. Soc. 125, 12118–12124. Web of Science PubMed Google Scholar
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. Web of Science CrossRef CAS IUCr Journals Google Scholar

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