Aqua­[4-chloro-2-(2-pyridylmethyl­imino­meth­yl)phenolato]copper(II) nitrate monohydrate

Liang, Q.; Chen, X.; Zhang, H.; Zou, Z.

doi:10.1107/S1600536809052350

Aqua[4-chloro-2-(2-pyridylmethyliminomethyl)phenolato]copper(II) nitrate monohydrate

In the title mononuclear complex, [Cu(C₁₃H₁₀ClN₂O)(H₂O)]NO₃·H₂O, the Cu^II atom is four-coordinated by two N atoms and one O atom of the tridentate Schiff base ligand and one O atom from the coordinated water molecule in a slightly distorted square-planar configuration. The nitrate ion interacts with the copper center [Cu1

O3 = 2.579 (4) Å]. In the crystal, the cations, anions and water molecules are linked by O—H

O and O—H

N hydrogen bonds.

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Supporting information

	Crystallographic Information File (CIF) https://doi.org/10.1107/S1600536809052350/zq2021sup1.cif Contains datablocks I, global
	Structure factor file (CIF format) https://doi.org/10.1107/S1600536809052350/zq2021Isup2.hkl Contains datablock I

CCDC reference: 766664

checkCIF report

Key indicators

Single-crystal X-ray study
T = 298 K
Mean (C-C) = 0.005 Å
R factor = 0.030
wR factor = 0.074
Data-to-parameter ratio = 12.4

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT241_ALERT_2_C Check High      Ueq as Compared to Neighbors for         O3
PLAT242_ALERT_2_C Check Low       Ueq as Compared to Neighbors for         N3
PLAT911_ALERT_3_C Missing # FCF Refl Between THmin & STh/L=  0.595         44
PLAT042_ALERT_1_C Calc. and Reported MoietyFormula Strings  Differ          ?

Alert level G
PLAT860_ALERT_3_G Note: Number of Least-Squares Restraints .......          1
PLAT710_ALERT_4_G Delete 1-2-3 or 2-3-4 Linear Torsion Angle ... #          2
            O2  -CU1 -N1  -C1   -106.30  0.70   1.555   1.555   1.555   1.555
PLAT710_ALERT_4_G Delete 1-2-3 or 2-3-4 Linear Torsion Angle ... #          5
            O2  -CU1 -N1  -C8     70.30  0.80   1.555   1.555   1.555   1.555
PLAT710_ALERT_4_G Delete 1-2-3 or 2-3-4 Linear Torsion Angle ... #          7
            O1  -CU1 -N2  -C13  -163.30  1.90   1.555   1.555   1.555   1.555
PLAT710_ALERT_4_G Delete 1-2-3 or 2-3-4 Linear Torsion Angle ... #         10
            O1  -CU1 -N2  -C9     12.00  2.00   1.555   1.555   1.555   1.555
PLAT710_ALERT_4_G Delete 1-2-3 or 2-3-4 Linear Torsion Angle ... #         15
            N2  -CU1 -O1  -C3    -19.00  2.00   1.555   1.555   1.555   1.555

   0 ALERT level A = In general: serious problem
   0 ALERT level B = Potentially serious problem
   4 ALERT level C = Check and explain
   6 ALERT level G = General alerts; check

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

Comment top

Metals ions are vital for living organisms because they are involved in many fundamental biological processes, e.g. copper proteins known to be involved in a crucial role, such as respiration, iron transport, oxidative stress protection, blood clotting and pigmentation (Arnesano et al., 2004). The study of copper compounds is of great interest in various aspects of chemistry (Downing & Urbach, 1969; Ganeshpure et al., 1996; Bosnich, 1968; Costes et al., 1995). The molecular structure of (I) is illustrated in Fig. 1, and selected bond distances and angles are given in Table 1. The Cu^II atom is four- coordinated by two nitrogen atoms and one oxygen atom of the tridentate Schiff base ligand, and one oxygen atom from the coordinated water molecule, forming a slightly distorted square-planar coordination configuration. The four coordinating atoms around the Cu centre are approximately coplanar. The Cu1—N2 bond [1.982 (2) Å; Table 1] is a little longer than the value [1.977 (4) Å] observed in a similar copper(II) complex (Sun et al., 2005). The Cu1—N1 bond length [1.936 (2) Å] is comparable with the corresponding value [1.934 (4) Å] observed in the same complex mentioned above (Sun et al., 2005). The Cu1—O1 bond length is 1.889 (18) Å. The nitrate ion is in interaction with the copper center [Cu1···O3 = 2.579 (4) Å]. The bond angles around the Cu^II centre show some deviations from ideal square-planar geometry. The Schiff base ligands from adjacent molecules are almost parallel due to by π-π interactions leading to the formation of two-dimensional parallel layers (Fig.2). The cations, anions and solvent water molecules are linked by O-H···O hydrogen bonds.

Related literature top

For the role of copper proteins in fundamental biological processes, see: Arnesano et al. (2004). For the chemistry of copper compounds, see: Bosnich (1968); Costes et al. (1995); Downing & Urbach (1969); Ganeshpure et al. (1996). For related structures, see: Sun et al. (2005); You et al. (2004). For related literature, see: Mizutani et al. (1999).

Experimental top

2-Aminomethylpyridine (0.1 mmol, 10.8 mg) and 5-chloro-salicylaldehyde (0.1 mmol, 15.6 mg) were dissolved in methanol (10 ml). The mixture was stirred for 1 h to give a clear yellow solution. To this solution was added a water solution (10 ml) of Cu(NO₃)2.3H₂O (0.1 mmol, 24.2 mg), with stirring. The mixture was stirred for 10 min to give a deep green solution, which was allowed to evaporate slowly in the open at room temperature. After 5 days, deep blue block-shaped crystals suitable for an X-ray diffraction study were formed at the bottom of the vessel.

Computing details top

Data collection: CrystalClear (Rigaku, 2005); cell refinement: CrystalClear (Rigaku, 2005); data reduction: CrystalClear (Rigaku, 2005); 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 structure of the title molecule, with the atom-numbering scheme. Displacement ellipsoids are drawn at the 30% probability level.
	Fig. 2. Crystal packing of the compound (I). Hydrogen bonds are shown as dashed lines.

Aqua[4-chloro-2-(2-pyridylmethyliminomethyl)phenolato]copper(II) nitrate monohydrate top

Crystal data top

[Cu(C₁₃H₁₀ClN₂O)(H₂O)]NO₃·H₂O	Z = 2
M_r = 407.26	F(000) = 414
Triclinic, P1	D_x = 1.729 Mg m⁻³
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 7.892 (2) Å	Cell parameters from 13380 reflections
b = 8.9741 (12) Å	θ = 1.8–25.0°
c = 11.8929 (15) Å	µ = 1.60 mm⁻¹
α = 106.841 (2)°	T = 298 K
β = 102.198 (1)°	Prism, dark blue
γ = 92.897 (1)°	0.47 × 0.41 × 0.30 mm
V = 782.3 (2) Å³

Data collection top

Rigaku SCXmini diffractometer	2714 independent reflections
Radiation source: Rotating Anode	2280 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.016
Detector resolution: 8.192 pixels mm^-1	θ_max = 25.0°, θ_min = 1.8°
ω scans	h = −9→9
Absorption correction: multi-scan (CrystalClear; Rigaku, 2005)	k = −8→10
T_min = 0.520, T_max = 0.645	l = −13→14
4114 measured reflections

Refinement top

Refinement on F²	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F² > 2σ(F²)] = 0.030	H-atom parameters constrained
wR(F²) = 0.074	w = 1/[σ²(F_o²) + (0.0271P)² + 0.5072P] where P = (F_o² + 2F_c²)/3
S = 1.06	(Δ/σ)_max = 0.001
2714 reflections	Δρ_max = 0.40 e Å⁻³
218 parameters	Δρ_min = −0.39 e Å⁻³
1 restraint	Extinction correction: SHELXL97 (Sheldrick, 2008), Fc^*=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.0320 (19)

Crystal data top

[Cu(C₁₃H₁₀ClN₂O)(H₂O)]NO₃·H₂O	γ = 92.897 (1)°
M_r = 407.26	V = 782.3 (2) Å³
Triclinic, P1	Z = 2
a = 7.892 (2) Å	Mo Kα radiation
b = 8.9741 (12) Å	µ = 1.60 mm⁻¹
c = 11.8929 (15) Å	T = 298 K
α = 106.841 (2)°	0.47 × 0.41 × 0.30 mm
β = 102.198 (1)°

Data collection top

Rigaku SCXmini diffractometer	2714 independent reflections
Absorption correction: multi-scan (CrystalClear; Rigaku, 2005)	2280 reflections with I > 2σ(I)
T_min = 0.520, T_max = 0.645	R_int = 0.016
4114 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.030	1 restraint
wR(F²) = 0.074	H-atom parameters constrained
S = 1.06	Δρ_max = 0.40 e Å⁻³
2714 reflections	Δρ_min = −0.39 e Å⁻³
218 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
Cu1	0.19716 (5)	0.40689 (4)	0.59865 (3)	0.03271 (17)
Cl1	0.01878 (15)	0.28462 (12)	−0.04586 (8)	0.0556 (3)
N1	0.2799 (3)	0.5546 (3)	0.5259 (2)	0.0322 (6)
N2	0.3181 (3)	0.5696 (3)	0.7513 (2)	0.0329 (6)
N3	0.4694 (4)	0.1517 (4)	0.6974 (3)	0.0448 (7)
O1	0.0888 (3)	0.2574 (2)	0.44856 (19)	0.0391 (6)
O2	0.0886 (3)	0.2783 (3)	0.6801 (2)	0.0380 (6)
H2A	0.1681	0.2270	0.7049	0.046*
H2B	0.0040	0.2104	0.6350	0.046*
O3	0.4553 (4)	0.2453 (3)	0.6385 (3)	0.0632 (8)
O4	0.5942 (5)	0.0744 (5)	0.6999 (4)	0.0921 (12)
O5	0.3572 (3)	0.1310 (3)	0.7528 (2)	0.0513 (7)
O6	0.8275 (3)	0.0554 (3)	0.5520 (2)	0.0496 (7)
H6A	0.8662	−0.0326	0.5462	0.059*
H6B	0.7557	0.0650	0.5970	0.059*
C1	0.2497 (4)	0.5376 (4)	0.4119 (3)	0.0322 (7)
H1	0.2942	0.6191	0.3888	0.039*
C2	0.1531 (4)	0.4032 (4)	0.3176 (3)	0.0304 (7)
C3	0.0765 (4)	0.2710 (4)	0.3398 (3)	0.0323 (7)
C4	−0.0198 (5)	0.1487 (4)	0.2394 (3)	0.0381 (8)
H4	−0.0726	0.0618	0.2520	0.046*
C5	−0.0380 (5)	0.1543 (4)	0.1237 (3)	0.0395 (8)
H5	−0.1028	0.0722	0.0589	0.047*
C6	0.0411 (5)	0.2835 (4)	0.1032 (3)	0.0375 (8)
C7	0.1338 (4)	0.4054 (4)	0.1972 (3)	0.0377 (8)
H7	0.1850	0.4911	0.1822	0.045*
C8	0.3778 (5)	0.7018 (4)	0.6111 (3)	0.0382 (8)
H8A	0.3138	0.7891	0.6030	0.046*
H8B	0.4901	0.7184	0.5928	0.046*
C9	0.4047 (4)	0.6945 (4)	0.7380 (3)	0.0328 (7)
C10	0.5091 (5)	0.8088 (4)	0.8357 (3)	0.0420 (9)
H10	0.5697	0.8927	0.8243	0.050*
C11	0.5229 (5)	0.7975 (4)	0.9502 (3)	0.0455 (9)
H11	0.5938	0.8729	1.0171	0.055*
C12	0.4294 (5)	0.6720 (4)	0.9639 (3)	0.0458 (9)
H12	0.4340	0.6634	1.0405	0.055*
C13	0.3297 (5)	0.5603 (4)	0.8633 (3)	0.0417 (9)
H13	0.2682	0.4755	0.8730	0.050*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Cu1	0.0408 (3)	0.0262 (2)	0.0313 (2)	−0.00137 (16)	0.00910 (17)	0.00954 (17)
Cl1	0.0840 (8)	0.0510 (6)	0.0315 (5)	0.0041 (5)	0.0125 (5)	0.0137 (4)
N1	0.0379 (16)	0.0245 (14)	0.0342 (15)	−0.0011 (11)	0.0080 (12)	0.0102 (12)
N2	0.0406 (16)	0.0255 (14)	0.0325 (15)	0.0042 (12)	0.0070 (12)	0.0101 (12)
N3	0.0422 (19)	0.0434 (18)	0.0477 (19)	−0.0011 (15)	0.0108 (15)	0.0134 (15)
O1	0.0565 (15)	0.0288 (12)	0.0320 (13)	−0.0077 (11)	0.0110 (11)	0.0112 (10)
O2	0.0428 (14)	0.0348 (13)	0.0371 (13)	−0.0023 (10)	0.0100 (10)	0.0131 (11)
O3	0.0651 (19)	0.0525 (17)	0.093 (2)	0.0078 (14)	0.0379 (17)	0.0412 (17)
O4	0.071 (2)	0.121 (3)	0.132 (3)	0.050 (2)	0.055 (2)	0.083 (3)
O5	0.0485 (16)	0.0679 (18)	0.0474 (15)	0.0065 (13)	0.0170 (13)	0.0288 (14)
O6	0.0546 (16)	0.0384 (14)	0.0572 (16)	−0.0014 (12)	0.0160 (13)	0.0162 (13)
C1	0.0331 (18)	0.0297 (17)	0.0395 (19)	0.0029 (14)	0.0115 (14)	0.0174 (15)
C2	0.0323 (17)	0.0266 (16)	0.0342 (17)	0.0037 (13)	0.0081 (14)	0.0119 (14)
C3	0.0364 (18)	0.0289 (17)	0.0338 (18)	0.0060 (14)	0.0105 (14)	0.0111 (14)
C4	0.046 (2)	0.0278 (18)	0.0387 (19)	−0.0032 (15)	0.0114 (16)	0.0083 (15)
C5	0.044 (2)	0.0333 (19)	0.0356 (19)	0.0023 (16)	0.0081 (15)	0.0043 (15)
C6	0.045 (2)	0.0371 (19)	0.0306 (18)	0.0078 (16)	0.0102 (15)	0.0099 (16)
C7	0.042 (2)	0.0374 (19)	0.0407 (19)	0.0049 (16)	0.0134 (15)	0.0194 (16)
C8	0.045 (2)	0.0274 (17)	0.0402 (19)	−0.0051 (15)	0.0077 (16)	0.0113 (15)
C9	0.0339 (18)	0.0261 (17)	0.0377 (18)	0.0064 (14)	0.0072 (14)	0.0091 (15)
C10	0.043 (2)	0.0322 (19)	0.046 (2)	−0.0008 (16)	0.0046 (16)	0.0095 (17)
C11	0.051 (2)	0.037 (2)	0.038 (2)	0.0044 (17)	−0.0016 (17)	0.0046 (17)
C12	0.062 (3)	0.039 (2)	0.0327 (19)	0.0069 (18)	0.0041 (17)	0.0095 (17)
C13	0.054 (2)	0.0351 (19)	0.0377 (19)	0.0024 (17)	0.0105 (17)	0.0140 (16)

Geometric parameters (Å, º) top

Cu1—O1	1.889 (2)	C2—C3	1.421 (4)
Cu1—N1	1.936 (3)	C3—C4	1.407 (4)
Cu1—O2	1.975 (2)	C4—C5	1.368 (5)
Cu1—N2	1.982 (3)	C4—H4	0.9300
Cl1—C6	1.747 (3)	C5—C6	1.396 (5)
N1—C1	1.288 (4)	C5—H5	0.9300
N1—C8	1.469 (4)	C6—C7	1.359 (5)
N2—C13	1.343 (4)	C7—H7	0.9300
N2—C9	1.349 (4)	C8—C9	1.500 (4)
N3—O4	1.233 (4)	C8—H8A	0.9700
N3—O3	1.236 (4)	C8—H8B	0.9700
N3—O5	1.247 (4)	C9—C10	1.379 (4)
O1—C3	1.318 (4)	C10—C11	1.376 (5)
O2—H2A	0.8500	C10—H10	0.9300
O2—H2B	0.8500	C11—C12	1.383 (5)
O6—H6A	0.8500	C11—H11	0.9300
O6—H6B	0.8499	C12—C13	1.372 (5)
C1—C2	1.433 (4)	C12—H12	0.9300
C1—H1	0.9300	C13—H13	0.9300
C2—C7	1.414 (4)

O1—Cu1—N1	93.94 (10)	C3—C4—H4	119.1
O1—Cu1—O2	88.85 (9)	C4—C5—C6	119.9 (3)
N1—Cu1—O2	171.60 (10)	C4—C5—H5	120.1
O1—Cu1—N2	176.81 (10)	C6—C5—H5	120.1
N1—Cu1—N2	82.98 (11)	C7—C6—C5	120.6 (3)
O2—Cu1—N2	94.32 (10)	C7—C6—Cl1	120.8 (3)
C1—N1—C8	118.5 (3)	C5—C6—Cl1	118.5 (3)
C1—N1—Cu1	125.9 (2)	C6—C7—C2	120.6 (3)
C8—N1—Cu1	115.6 (2)	C6—C7—H7	119.7
C13—N2—C9	118.7 (3)	C2—C7—H7	119.7
C13—N2—Cu1	125.8 (2)	N1—C8—C9	109.7 (3)
C9—N2—Cu1	115.3 (2)	N1—C8—H8A	109.7
O4—N3—O3	120.0 (3)	C9—C8—H8A	109.7
O4—N3—O5	118.9 (3)	N1—C8—H8B	109.7
O3—N3—O5	121.1 (3)	C9—C8—H8B	109.7
C3—O1—Cu1	127.6 (2)	H8A—C8—H8B	108.2
Cu1—O2—H2A	105.5	N2—C9—C10	121.7 (3)
Cu1—O2—H2B	115.4	N2—C9—C8	115.8 (3)
H2A—O2—H2B	106.1	C10—C9—C8	122.5 (3)
H6A—O6—H6B	107.8	C11—C10—C9	119.5 (3)
N1—C1—C2	125.3 (3)	C11—C10—H10	120.3
N1—C1—H1	117.3	C9—C10—H10	120.3
C2—C1—H1	117.3	C10—C11—C12	118.7 (3)
C7—C2—C3	119.4 (3)	C10—C11—H11	120.6
C7—C2—C1	117.3 (3)	C12—C11—H11	120.6
C3—C2—C1	123.4 (3)	C13—C12—C11	119.4 (3)
O1—C3—C4	118.5 (3)	C13—C12—H12	120.3
O1—C3—C2	123.8 (3)	C11—C12—H12	120.3
C4—C3—C2	117.7 (3)	N2—C13—C12	122.1 (3)
C5—C4—C3	121.8 (3)	N2—C13—H13	119.0
C5—C4—H4	119.1	C12—C13—H13	119.0

O1—Cu1—N1—C1	2.8 (3)	O1—C3—C4—C5	−179.8 (3)
O2—Cu1—N1—C1	−106.3 (7)	C2—C3—C4—C5	1.0 (5)
N2—Cu1—N1—C1	−178.0 (3)	C3—C4—C5—C6	0.3 (5)
O1—Cu1—N1—C8	179.4 (2)	C4—C5—C6—C7	−1.1 (5)
O2—Cu1—N1—C8	70.3 (8)	C4—C5—C6—Cl1	178.7 (3)
N2—Cu1—N1—C8	−1.4 (2)	C5—C6—C7—C2	0.5 (5)
O1—Cu1—N2—C13	−163.3 (19)	Cl1—C6—C7—C2	−179.3 (3)
N1—Cu1—N2—C13	−178.8 (3)	C3—C2—C7—C6	0.8 (5)
O2—Cu1—N2—C13	9.1 (3)	C1—C2—C7—C6	−178.7 (3)
O1—Cu1—N2—C9	12 (2)	C1—N1—C8—C9	−177.7 (3)
N1—Cu1—N2—C9	−3.5 (2)	Cu1—N1—C8—C9	5.5 (4)
O2—Cu1—N2—C9	−175.5 (2)	C13—N2—C9—C10	2.4 (5)
N1—Cu1—O1—C3	−3.4 (3)	Cu1—N2—C9—C10	−173.3 (3)
O2—Cu1—O1—C3	168.7 (3)	C13—N2—C9—C8	−176.7 (3)
N2—Cu1—O1—C3	−19 (2)	Cu1—N2—C9—C8	7.6 (4)
C8—N1—C1—C2	−178.5 (3)	N1—C8—C9—N2	−8.4 (4)
Cu1—N1—C1—C2	−2.0 (5)	N1—C8—C9—C10	172.5 (3)
N1—C1—C2—C7	−179.8 (3)	N2—C9—C10—C11	−1.4 (5)
N1—C1—C2—C3	0.7 (5)	C8—C9—C10—C11	177.7 (3)
Cu1—O1—C3—C4	−176.1 (2)	C9—C10—C11—C12	−0.8 (5)
Cu1—O1—C3—C2	3.1 (5)	C10—C11—C12—C13	1.8 (6)
C7—C2—C3—O1	179.3 (3)	C9—N2—C13—C12	−1.3 (5)
C1—C2—C3—O1	−1.2 (5)	Cu1—N2—C13—C12	173.9 (3)
C7—C2—C3—C4	−1.5 (5)	C11—C12—C13—N2	−0.8 (6)
C1—C2—C3—C4	178.0 (3)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O2—H2a···O5	0.85	1.83	2.676 (4)	173
O2—H2a···N3	0.85	2.52	3.253 (4)	146
O2—H2a···O3	0.85	2.57	3.052 (4)	117
O2—H2b···O6ⁱ	0.85	1.81	2.657 (4)	174
O6—H6a···O1ⁱⁱ	0.85	2.08	2.915 (3)	166
O6—H6b···O4	0.85	1.93	2.782 (5)	177

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

Experimental details

Crystal data
Chemical formula	[Cu(C₁₃H₁₀ClN₂O)(H₂O)]NO₃·H₂O
M_r	407.26
Crystal system, space group	Triclinic, P1
Temperature (K)	298
a, b, c (Å)	7.892 (2), 8.9741 (12), 11.8929 (15)
α, β, γ (°)	106.841 (2), 102.198 (1), 92.897 (1)
V (Å³)	782.3 (2)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	1.60
Crystal size (mm)	0.47 × 0.41 × 0.30

Data collection
Diffractometer	Rigaku SCXmini diffractometer
Absorption correction	Multi-scan (CrystalClear; Rigaku, 2005)
T_min, T_max	0.520, 0.645
No. of measured, independent and observed [I > 2σ(I)] reflections	4114, 2714, 2280
R_int	0.016
(sin θ/λ)_max (Å⁻¹)	0.595

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.030, 0.074, 1.06
No. of reflections	2714
No. of parameters	218
No. of restraints	1
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.40, −0.39

Computer programs: CrystalClear (Rigaku, 2005), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Selected geometric parameters (Å, º) top

Cu1—O1	1.889 (2)	Cu1—O2	1.975 (2)
Cu1—N1	1.936 (3)	Cu1—N2	1.982 (3)

O1—Cu1—N1	93.94 (10)	O1—Cu1—N2	176.81 (10)
O1—Cu1—O2	88.85 (9)	N1—Cu1—N2	82.98 (11)
N1—Cu1—O2	171.60 (10)	O2—Cu1—N2	94.32 (10)