Poly[(μ3-3,5-di­nitro­benzoato-κ3O1:O1′:O3)(μ2-hydroxido-κ2O:O)copper(II)]

Sinha, B.; Dey, G.C.; Sarkar, B.; Roy, A.; Ng, S.W.; Tiekink, E.R.T.

doi:10.1107/S1600536814004280

metal-organic compounds

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Volume 70| Part 3| March 2014| Pages m112-m113

doi:10.1107/S1600536814004280

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Poly[(μ₃-3,5-dinitrobenzoato-κ³O¹:O^1′:O³)(μ₂-hydroxido-κ²O:O)copper(II)]

B. Sinha,^a G. C. Dey,^a B. Sarkar,^a A. Roy,^a ‡ Seik Weng Ng ^b,^c and Edward R. T. Tiekink ^b ^*

^aDepartment of Chemistry, North Bengal University, Dt. Darjeeling, West Bengal 734 013, India, ^bDepartment of Chemistry, University of Malaya, 50603 Kuala Lumpur, Malaysia, and ^cChemistry Department, Faculty of Science, King Abdulaziz University, PO Box 80203 Jeddah, Saudi Arabia
^*Correspondence e-mail: edward.tiekink@gmail.com

(Received 24 February 2014; accepted 25 February 2014; online 28 February 2014)

The title complex, [Cu{μ₃-O₂CC₆H₃(NO₂)₂-3,5}(μ-OH)]_n, features zigzag chains in which successive pairs of Cu^II atoms are connected by OH bridges and bidentate carboxylate ligands, leading to six-membered Cu(O)(OCO)Cu rings. The zigzag chains are connected into a three-dimensional architecture by Cu—O(nitro) bonds. The coordination geometry of the Cu^II atom is square-pyramidal, with the axial position occupied by the nitro O atom, which forms the longer Cu—O bond. Bifurcated hydroxy–nitro O—H⋯O hydrogen bonds contribute to the stability of the crystal structure.

CCDC reference: 988599

Related literature

For related Cu^II structures featuring Cu(μ₂-carboxylate)(μ₂-hydroxyl)Cu rings, see: You et al. (2005 ); Chen et al. (2006 ); Xiao et al. (2006 ). For additional structural analysis, see: Addison et al. (1984 ).

Experimental

Crystal data

[Cu(C₇H₃N₂O₆)(OH)]
M_r = 291.66
Orthorhombic, P n a 2₁
a = 7.4665 (2) Å
b = 17.7858 (5) Å
c = 6.6821 (2) Å
V = 887.37 (4) Å³
Z = 4
Cu Kα radiation
μ = 3.87 mm⁻¹
T = 100 K
0.25 × 0.20 × 0.15 mm

Data collection

Agilent SuperNova Dual diffractometer with an Atlas detector
Absorption correction: multi-scan (CrysAlis PRO; Agilent, 2011 ) T_min = 0.873, T_max = 1.000
3156 measured reflections
1324 independent reflections
1318 reflections with I > 2σ(I)
R_int = 0.017

Refinement

R[F² > 2σ(F²)] = 0.027
wR(F²) = 0.077
S = 1.05
1324 reflections
155 parameters
1 restraint
H-atom parameters constrained
Δρ_max = 0.45 e Å⁻³
Δρ_min = −0.67 e Å⁻³
Absolute structure: Flack (1983 ), 360 Friedel pairs
Absolute structure parameter: 0.06 (5)

Table 1
Selected bond lengths (Å)

Cu—O1	1.9689 (18)
Cu—O7	1.899 (2)
Cu—O2ⁱ	1.9675 (18)
Cu—O5ⁱⁱ	2.5871 (18)
Cu—O7ⁱ	1.900 (2)
Symmetry codes: (i) $[-x, -y+1, z-{\script{1\over 2}}]$ ; (ii) $[x-{\script{1\over 2}}, -y+{\script{1\over 2}}, z]$ .

Table 2
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O7—H1⋯O3ⁱⁱⁱ	0.84	2.52	3.190 (3)	137
O7—H1⋯O4ⁱⁱⁱ	0.84	2.57	3.271 (2)	142
Symmetry code: (iii) $[-x-{\script{1\over 2}}, y+{\script{1\over 2}}, z-{\script{1\over 2}}]$ .

Data collection: CrysAlis PRO (Agilent, 2011); cell refinement: CrysAlis PRO; data reduction: CrysAlis PRO; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012 ) and DIAMOND (Brandenburg, 2006 ); software used to prepare material for publication: publCIF (Westrip, 2010 ).

Supporting information

CCDC reference: 988599

Crystal structure: contains datablocks general, I. DOI: 10.1107/S1600536814004280/hg5386sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536814004280/hg5386Isup2.hkl

checkCIF report

Structural commentary top

The title complex was synthesised employing hydrothermal methods, and X-ray crystallography revealed it to be three-dimensional. The crystallographic asymmetric unit comprises a Cu^II cation, and 3,5-dinitrobenzoate and hydroxide anions, Fig. 1. Zigzag rows of Cu^II ions are aligned along the c axis (glide symmetry) with pairs of Cu^II ions being bridged by a hydroxide and two O atoms of the carboxylate ligand leading to chains of six-membered rings. Neighbouring chains are linked via Cu—O(nitro) bonds, which are longer than the remaining Cu—O bonds, Table 1. The resulting O₅ donor set defines an axially distorted square pyramidal coordination geometry, with the nitro-O atom in the axial position, as quantified by the value of τ = 0.01 which compares to the τ values of 0.0 and 1.0 for ideal square pyramidal and trigonal bipyramidal geometries, respectively (Addison et al., 1984). Additional stability to the architecture is provided by bifurcated O—H···O(nitro) hydrogen bonds, Table 2.

Similar strings of Cu(µ₂-carboxylate)(µ₂-hydroxyl)Cu of varying dimensionality have been noted in other Cu^II structures (e.g. Chen et al., 2006; You et al., 2005; Xiao et al., 2006).

Synthesis and crystallization top

To a pulverised mixture of 3,5-dinitrobenzoic acid (0.1688 g), Cu(NO₃)₂.3H₂O (0.1932 g) and melamine (0.1002 g), all obtained from commercial sources in AR grade, distilled water (1.5 ml) was added. The mixture was stirred for 30 min to get a suspension. The reaction mixture was then sealed in a 10 ml Teflon-lined stainless steel autoclave and heated at 423 K for 45 h. The autoclave was subjected to natural cooling (for 5 h) to room temperature. The product containing blue crystals suitable for single crystal X-ray diffraction was collected by filtration and washed with adequate distilled water. The initial pH of the suspension was 5 and there was no apparent change in the pH when the reaction was over. The blue product was not formed in the absence of melamine which suggests that melamine acted as a base in this reaction. The product decomposed with explosion with green flashes above 553 K.

Refinement top

The H atoms were geometrically placed (O—H = 0.84 Å and C—H = 0.95 Å) and refined as riding with U_iso(H) = 1.2–1.5U_eq(O, C).

Related literature top

For related Cu^II structures featuring Cu(µ₂-carboxylate)(µ₂-hydroxyl)Cu rings, see: You et al. (2005); Chen et al. (2006); Xiao et al. (2006). For additional structural analysis, see: Addison et al. (1984).

Computing details top

Data collection: CrysAlis PRO (Agilent, 2011); cell refinement: CrysAlis PRO (Agilent, 2011); data reduction: CrysAlis PRO (Agilent, 2011); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012) and DIAMOND (Brandenburg, 2006); software used to prepare material for publication: publCIF (Westrip, 2010).

Figures top

	Fig. 1. The asymmetric unit of the title compound showing the atom-labelling scheme and displacement ellipsoids at the 70% probability level.
	Fig. 2. A view approximately normal to the zigzag chain along the c axis in the title compound. The coordinating nitro groups from carboxylates belong to other chains are shown as "O₂NC", for reasons of clarity.
	Fig. 3. A view of the unit-cell contents of the title compound in projection down the c axis, the axis along which the zigzag chains are propagated. The O—H···O hydrogen bonds are shown as orange dashed lines.

Poly[(µ₃-3,5-dinitrobenzoato-κ³O¹:O^1':O³)(µ₂-hydroxido-κ²O:O)copper(II)] top

Crystal data top

[Cu(C₇H₃N₂O₆)(OH)]	F(000) = 580
M_r = 291.66	D_x = 2.183 Mg m⁻³
Orthorhombic, Pna2₁	Cu Kα radiation, λ = 1.54184 Å
Hall symbol: P 2c -2n	Cell parameters from 2719 reflections
a = 7.4665 (2) Å	θ = 5.0–74.1°
b = 17.7858 (5) Å	µ = 3.87 mm⁻¹
c = 6.6821 (2) Å	T = 100 K
V = 887.37 (4) Å³	Prism, blue
Z = 4	0.25 × 0.20 × 0.15 mm

Data collection top

Agilent SuperNova Dual diffractometer with an Atlas detector	1324 independent reflections
Radiation source: SuperNova (Cu) X-ray Source	1318 reflections with I > 2σ(I)
Mirror monochromator	R_int = 0.017
Detector resolution: 10.4041 pixels mm^-1	θ_max = 74.3°, θ_min = 5.0°
ω scan	h = −6→9
Absorption correction: multi-scan (CrysAlis PRO; Agilent, 2011)	k = −20→21
T_min = 0.873, T_max = 1.000	l = −7→8
3156 measured reflections

Refinement top

Refinement on F²	Hydrogen site location: inferred from neighbouring sites
Least-squares matrix: full	H-atom parameters constrained
R[F² > 2σ(F²)] = 0.027	w = 1/[σ²(F_o²) + (0.0617P)² + 0.2234P] where P = (F_o² + 2F_c²)/3
wR(F²) = 0.077	(Δ/σ)_max = 0.001
S = 1.05	Δρ_max = 0.45 e Å⁻³
1324 reflections	Δρ_min = −0.67 e Å⁻³
155 parameters	Extinction correction: SHELXL97 (Sheldrick, 2008), Fc^*=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4
1 restraint	Extinction coefficient: 0.0078 (6)
Primary atom site location: structure-invariant direct methods	Absolute structure: Flack (1983), 360 Friedel pairs
Secondary atom site location: difference Fourier map	Absolute structure parameter: 0.06 (5)

Crystal data top

[Cu(C₇H₃N₂O₆)(OH)]	V = 887.37 (4) Å³
M_r = 291.66	Z = 4
Orthorhombic, Pna2₁	Cu Kα radiation
a = 7.4665 (2) Å	µ = 3.87 mm⁻¹
b = 17.7858 (5) Å	T = 100 K
c = 6.6821 (2) Å	0.25 × 0.20 × 0.15 mm

Data collection top

Agilent SuperNova Dual diffractometer with an Atlas detector	1324 independent reflections
Absorption correction: multi-scan (CrysAlis PRO; Agilent, 2011)	1318 reflections with I > 2σ(I)
T_min = 0.873, T_max = 1.000	R_int = 0.017
3156 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.027	H-atom parameters constrained
wR(F²) = 0.077	Δρ_max = 0.45 e Å⁻³
S = 1.05	Δρ_min = −0.67 e Å⁻³
1324 reflections	Absolute structure: Flack (1983), 360 Friedel pairs
155 parameters	Absolute structure parameter: 0.06 (5)
1 restraint

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
Cu	0.00521 (5)	0.502896 (17)	0.50002 (17)	0.00920 (17)
O1	0.0918 (2)	0.40286 (10)	0.5811 (3)	0.0146 (4)
O2	0.0673 (3)	0.39533 (9)	0.9179 (3)	0.0136 (4)
O3	−0.0991 (3)	0.14441 (11)	1.1700 (3)	0.0155 (4)
O4	−0.0088 (2)	0.04569 (11)	1.0096 (4)	0.0186 (4)
O5	0.2389 (2)	0.07033 (9)	0.3473 (3)	0.0141 (4)
O6	0.3041 (2)	0.18099 (10)	0.2336 (3)	0.0187 (4)
O7	−0.1161 (2)	0.51396 (9)	0.7481 (3)	0.0105 (4)
H1	−0.2242	0.5270	0.7463	0.016*
N1	−0.0260 (3)	0.11347 (12)	1.0269 (4)	0.0124 (5)
N2	0.2439 (3)	0.13903 (11)	0.3632 (3)	0.0119 (4)
C1	0.0847 (3)	0.36866 (12)	0.7455 (4)	0.0099 (4)
C2	0.0984 (3)	0.28424 (13)	0.7318 (4)	0.0110 (5)
C3	0.0397 (4)	0.23927 (14)	0.8891 (4)	0.0121 (5)
H3	−0.0025	0.2611	1.0100	0.014*
C4	0.0445 (4)	0.16166 (14)	0.8649 (4)	0.0109 (5)
C5	0.1101 (4)	0.12656 (13)	0.6959 (4)	0.0108 (5)
H5	0.1135	0.0734	0.6839	0.013*
C6	0.1710 (3)	0.17364 (13)	0.5442 (4)	0.0113 (5)
C7	0.1637 (3)	0.25149 (13)	0.5565 (4)	0.0111 (5)
H7	0.2024	0.2819	0.4478	0.013*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Cu	0.0143 (3)	0.0092 (2)	0.0042 (3)	0.00052 (10)	0.00062 (13)	0.00047 (15)
O1	0.0228 (10)	0.0118 (8)	0.0092 (9)	0.0025 (6)	0.0030 (7)	0.0015 (7)
O2	0.0210 (10)	0.0118 (8)	0.0081 (9)	0.0024 (7)	−0.0017 (7)	−0.0004 (7)
O3	0.0177 (9)	0.0182 (9)	0.0105 (9)	−0.0005 (8)	0.0047 (7)	−0.0002 (7)
O4	0.0268 (11)	0.0112 (8)	0.0179 (10)	−0.0027 (6)	0.0038 (8)	0.0013 (10)
O5	0.0173 (9)	0.0119 (8)	0.0129 (9)	0.0024 (6)	−0.0015 (7)	−0.0019 (7)
O6	0.0258 (10)	0.0180 (9)	0.0122 (9)	−0.0006 (7)	0.0079 (9)	0.0013 (8)
O7	0.0124 (9)	0.0129 (7)	0.0061 (8)	0.0010 (6)	−0.0013 (8)	−0.0012 (8)
N1	0.0134 (10)	0.0153 (10)	0.0085 (12)	0.0000 (8)	−0.0008 (8)	0.0025 (9)
N2	0.0131 (10)	0.0150 (9)	0.0075 (10)	0.0030 (7)	−0.0005 (8)	−0.0006 (8)
C1	0.0092 (10)	0.0126 (11)	0.0080 (11)	0.0015 (8)	−0.0009 (10)	−0.0015 (10)
C2	0.0111 (10)	0.0121 (11)	0.0099 (12)	0.0004 (9)	−0.0028 (11)	0.0014 (11)
C3	0.0124 (11)	0.0158 (13)	0.0080 (12)	0.0018 (9)	−0.0014 (10)	−0.0014 (10)
C4	0.0116 (11)	0.0130 (12)	0.0081 (12)	−0.0019 (9)	−0.0010 (11)	0.0033 (9)
C5	0.0118 (11)	0.0109 (11)	0.0098 (13)	0.0012 (9)	−0.0010 (9)	−0.0007 (9)
C6	0.0113 (11)	0.0144 (10)	0.0081 (13)	0.0010 (8)	−0.0022 (9)	−0.0003 (8)
C7	0.0121 (11)	0.0117 (10)	0.0095 (12)	−0.0004 (9)	−0.0016 (9)	−0.0009 (8)

Geometric parameters (Å, º) top

Cu—O1	1.9689 (18)	O7—H1	0.8400
Cu—O7	1.899 (2)	N1—C4	1.478 (3)
Cu—O2ⁱ	1.9675 (18)	N2—C6	1.462 (3)
Cu—O5ⁱⁱ	2.5871 (18)	C1—C2	1.508 (3)
Cu—O7ⁱ	1.900 (2)	C2—C3	1.392 (4)
O1—C1	1.257 (4)	C2—C7	1.396 (4)
O2—C1	1.252 (3)	C3—C4	1.390 (4)
O2—Cuⁱⁱⁱ	1.9675 (18)	C3—H3	0.9500
O3—N1	1.231 (3)	C4—C5	1.380 (4)
O4—N1	1.218 (3)	C5—C6	1.391 (3)
O5—N2	1.227 (3)	C5—H5	0.9500
O6—N2	1.228 (3)	C6—C7	1.388 (3)
O7—Cuⁱⁱⁱ	1.900 (2)	C7—H7	0.9500

O7—Cu—O7ⁱ	176.03 (4)	O2—C1—O1	128.7 (2)
O7—Cu—O2ⁱ	90.98 (8)	O2—C1—C2	116.1 (2)
O7ⁱ—Cu—O2ⁱ	91.02 (9)	O1—C1—C2	115.2 (2)
O7—Cu—O1	90.57 (9)	C3—C2—C7	120.3 (2)
O7ⁱ—Cu—O1	87.60 (8)	C3—C2—C1	120.3 (2)
O2ⁱ—Cu—O1	176.81 (9)	C7—C2—C1	119.4 (2)
O7—Cu—O5ⁱⁱ	91.71 (7)	C4—C3—C2	118.3 (2)
O7ⁱ—Cu—O5ⁱⁱ	84.60 (8)	C4—C3—H3	120.8
O2ⁱ—Cu—O5ⁱⁱ	98.13 (7)	C2—C3—H3	120.8
O1—Cu—O5ⁱⁱ	84.60 (7)	C5—C4—C3	123.6 (2)
C1—O1—Cu	131.60 (17)	C5—C4—N1	117.6 (2)
C1—O2—Cuⁱⁱⁱ	129.32 (16)	C3—C4—N1	118.8 (2)
Cu—O7—Cuⁱⁱⁱ	123.32 (10)	C4—C5—C6	116.1 (2)
Cu—O7—H1	118.3	C4—C5—H5	122.0
Cuⁱⁱⁱ—O7—H1	118.3	C6—C5—H5	122.0
O4—N1—O3	124.3 (2)	C7—C6—C5	123.0 (2)
O4—N1—C4	117.8 (2)	C7—C6—N2	118.9 (2)
O3—N1—C4	117.9 (2)	C5—C6—N2	118.1 (2)
O5—N2—O6	123.7 (2)	C6—C7—C2	118.6 (2)
O5—N2—C6	118.7 (2)	C6—C7—H7	120.7
O6—N2—C6	117.62 (19)	C2—C7—H7	120.7

O7—Cu—O1—C1	−8.5 (2)	O4—N1—C4—C5	6.0 (3)
O7ⁱ—Cu—O1—C1	175.0 (2)	O3—N1—C4—C5	−173.7 (2)
O2ⁱ—Cu—O7—Cuⁱⁱⁱ	−127.01 (11)	O4—N1—C4—C3	−174.7 (2)
O1—Cu—O7—Cuⁱⁱⁱ	50.20 (11)	O3—N1—C4—C3	5.7 (4)
Cuⁱⁱⁱ—O2—C1—O1	14.1 (4)	C3—C4—C5—C6	−0.9 (4)
Cuⁱⁱⁱ—O2—C1—C2	−165.63 (15)	N1—C4—C5—C6	178.3 (2)
Cu—O1—C1—O2	−22.7 (4)	C4—C5—C6—C7	−1.5 (3)
Cu—O1—C1—C2	156.98 (16)	C4—C5—C6—N2	179.2 (2)
O2—C1—C2—C3	19.2 (3)	O5—N2—C6—C7	−175.1 (2)
O1—C1—C2—C3	−160.6 (2)	O6—N2—C6—C7	3.6 (3)
O2—C1—C2—C7	−163.4 (2)	O5—N2—C6—C5	4.2 (3)
O1—C1—C2—C7	16.8 (3)	O6—N2—C6—C5	−177.0 (2)
C7—C2—C3—C4	−1.3 (4)	C5—C6—C7—C2	2.4 (3)
C1—C2—C3—C4	176.0 (2)	N2—C6—C7—C2	−178.3 (2)
C2—C3—C4—C5	2.3 (4)	C3—C2—C7—C6	−0.9 (3)
C2—C3—C4—N1	−176.9 (2)	C1—C2—C7—C6	−178.3 (2)

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

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O7—H1···O3^iv	0.84	2.52	3.190 (3)	137
O7—H1···O4^iv	0.84	2.57	3.271 (2)	142

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

Selected bond lengths (Å) top

Cu—O1	1.9689 (18)	Cu—O5ⁱⁱ	2.5871 (18)
Cu—O7	1.899 (2)	Cu—O7ⁱ	1.900 (2)
Cu—O2ⁱ	1.9675 (18)

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

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O7—H1···O3ⁱⁱⁱ	0.84	2.52	3.190 (3)	137
O7—H1···O4ⁱⁱⁱ	0.84	2.57	3.271 (2)	142

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

Footnotes

‡Additional correspondence author, e-mail: abhijitchem1947@yahoo.co.in.

Acknowledgements

This research was supported by High Impact Research MoE grant UM.C/625/1/HIR/MoE/SC/03 from the Ministry of Higher Education Malaysia.

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Volume 70| Part 3| March 2014| Pages m112-m113

doi:10.1107/S1600536814004280

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