Crystal structure of poly[di­aqua­(μ-2-carb­oxy­acetato-κ3O,O′:O′′)(2-carb­oxy­acetato-κO)di-μ-chlorido-dicobalt(II)]

Bouaoud, Y.; Setifi, Z.; Buvailo, A.; Potaskalov, V.A.; Merazig, H.; Dénés, G.

doi:10.1107/S2056989015023269

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Volume 72| Part 1| January 2016| Pages 21-24

doi:10.1107/S2056989015023269

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Crystal structure of poly[diaqua(μ-2-carboxyacetato-κ³O,O′:O′′)(2-carboxyacetato-κO)di-μ-chlorido-dicobalt(II)]

Yasmina Bouaoud,^a Zouaoui Setifi,^a,^b ^* Andrii Buvailo,^c,^d ^* Vadim A. Potaskalov,^e Hocine Merazig ^a and Georges Dénés ^f

^aUnité de Recherche de Chimie de l'Environnement et Moléculaire Structurale (CHEMS), Université Constantine 1, Constantine 25000, Algeria, ^bLaboratoire de Chimie, Ingénierie Moléculaire et Nanostructures (LCIMN), Université Ferhat Abbas Sétif 1, Sétif 19000, Algeria, ^cNational Taras Shevchenko University of Kyiv, Department of Chemistry, Volodymyrska str. 64, 01601 Kiev, Ukraine, ^dSciMax LLC, 2 Marshala Yakubovskogo str. 03191, Kyiv, Ukraine, ^eDepartment of General and Inorganic Chemistry, National Technical University of Ukraine, `Kyiv Polytechnic Institute', 37 Prospect Peremogy, 03056 Kiev, Ukraine, and ^fLaboratory of Solid State Chemistry and Mössbauer Spectroscopy, Laboratories for Inorganic Materials, Department of Chemistry and Biochemistry, Concordia University, Montréal, Québec, H3G 1M8, Canada
^*Correspondence e-mail: setifi_zouaoui@yahoo.fr, futureintentions@gmail.com

Edited by M. Weil, Vienna University of Technology, Austria (Received 2 November 2015; accepted 3 December 2015; online 1 January 2016)

The asymmetric unit of the title polymer, [Co₂(C₃H₃O₄)₂Cl₂(H₂O)₂]_n, comprises one Co^II atom, one water molecule, one singly deprotonated malonic acid molecule (HMal⁻; systematic name 2-carboxyacetate) and one Cl⁻ anion. The Co^II atom is octahedrally coordinated by the O atom of a water molecule, by one terminally bound carboxylate O atom of an HMal⁻ anion and by two O atoms of a chelating HMal⁻ anion, as well as by two Cl⁻ anions. The Cl⁻ anions bridge two Co^II atoms, forming a centrosymmetric Co₂Cl₂ core. Each malonate ligand is involved in the formation of six-membered chelate rings involving one Co^II atom of the dinuclear unit and at the same time is coordinating to another Co^II atom of a neighbouring dinuclear unit in a bridging mode. The combination of chelating and bridging coordination modes leads to the formation of a two-dimensional coordination polymer extending parallel to (001). Within a layer, O—H_water⋯Cl and O—H_water⋯O hydrogen bonds are present. Adjacent layers are linked through O—H⋯O=C hydrogen bonds involving the carboxylic acid OH and carbonyl groups.

Keywords: crystal structure; malonate; cobalt; coordination polymer.

CCDC reference: 1440440

1. Chemical context

Complexes with paramagnetic metal ions and extended structures are interesting due to their potential applications in molecular magnetism (Moroz et al., 2012 ; Pavlishchuk et al., 2010 , 2011 ; Yuste et al., 2009 ). Malonic acid exhibits both chelating and bridging modes of coordination and is an efficient ligand for achieving two- or three-dimensional polymeric structures (Delgado et al., 2004 ). In the present communication we report on the structure of a two-dimensional coordination polymer, [Co(C₃H₃O₄)Cl(H₂O)]_n, containing both chelating and bridging functions of singly deprotonated malonic acid ligands.

2. Structural commentary

The structure of the title compound is characterized by the presence of a two-dimensional coordination polymer extending parallel to (001). The monomeric fragment can be described as being composed of a centrosymmetric binuclear Co₂Cl₄ motif with the Co^II atoms having an overall distorted octahedral environment. The two octahedra are fused together via two bridging Cl atoms with Co—Cl bond lengths of 2.4312 (12) and 2.4657 (16) Å.

In the octahedron, the Cl⁻ atoms occupy equatorial positions, the other two equatorial positions being defined by the carboxylate O atom of a bridging hydrogenmalonate anion (HMal⁻) and one O atom of a chelating HMal⁻ anion, while one water O atom and the other O atom of the chelating HMal⁻ anion are in axial positions (Fig. 1). The corresponding Co—O_malonate bond lengths range from 2.051 (3) to 2.165 (3) Å which is similar to other structures containing this ligand in chelating and bridging modes (Delgado et al., 2004). The Co—O_water bond has a length of 2.046 (3) Å. The C—O bond lengths in the carboxylic group differ significantly [1.225 (2) and 1.306 (4) Å] while those in the carboxylate group [1.258 (4) and 1.267 (4) Å] are more or less the same, which is typical for this functional group (Wörl et al., 2005a ,b ).

Figure 1
A fragment of the title coordination polymer, showing the atom labelling. All H atoms, except those of hydroxy groups, have been omitted for clarity. Displacement ellipsoids are drawn at the 30% probability level. The intralayer O—H⋯Cl hydrogen bonds are shown as dashed lines. [Symmetry codes: (a) $[{1\over 2}]$ + x, $[{3\over 2}]$ − y, 1 − z; (b) 1 − x, 1 − y, 1 − z; (c) $[{3\over 2}]$ − x, − $[{1\over 2}]$ + y, z; (d) $[{3\over 2}]$ − x, $[{1\over 2}]$ + y, z.]

3. Supramolecular features

The distribution of the dinuclear units within a coordination layer follows a chess-like pattern whereby each dinuclear coordination node is interconnected with each other through four bridging HMal⁻ ligands (Fig. 2). The binuclear coordination nodes are additionally connected via intralayer O—H_water⋯Cl and O—H_water⋯O hydrogen bonds (Table 1 and Fig. 3). Adjacent layers are linked along [001] via interlayer O—H⋯O=C hydrogen bonds involving two HMal⁻ ligands (Table 1 and Fig. 3).

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O2—H1O2⋯O5ⁱ	0.93	1.94	2.689 (4)	136
O2—H2O2⋯Cl1ⁱⁱ	0.92	2.32	3.135 (3)	147
O4—H1O4⋯O1ⁱⁱⁱ	0.97	1.67	2.629 (4)	169
Symmetry codes: (i) $[-x+{\script{3\over 2}}, y-{\script{1\over 2}}, z]$ ; (ii) $[x-{\script{1\over 2}}, -y+{\script{1\over 2}}, -z+1]$ ; (iii) $[-x+1, y-{\script{1\over 2}}, -z+{\script{3\over 2}}]$ .

Figure 2
A view of the polymeric coordination layer in the crystal of the title compound, extending parallel to (001).

Figure 3
A view along [010] of the crystal packing of the title compound showing the inter- and intralayer hydrogen-bonding system (dashed lines).

4. Database survey

A search of the Cambridge Structural Database (Groom & Allen, 2014 ) revealed a number of coordination polymeric structures containing cobalt(II) malonate moieties in different coordination modes. While the most typical coordination mode of malonate ligands in polymeric structures appears to be a μ₃-bridging mode of the fully deprotonated acid involving all four oxygen atoms (usually two of them forming a chelating ring with one Co^II atom) (Delgado et al., 2004; Xue et al., 2003 ; Lightfoot & Snedden, 1999 ; Walter-Levy et al., 1973 ; Zheng & Xie, 2004 ; Montney et al., 2008 ; Fu et al., 2006 ; Djeghri et al., 2006 ), there are also cases of less-common coordination modes in polymeric structures such as a μ₂-bridging mode of the fully deprotonated ligand connecting two metal atoms (Gil de Muro et al., 1999 ; Pérez-Yáñez et al., 2009 ; Jin & Chen, 2007 ). Much less common in coordination polymers is a mono-deprotonated state of malonic acid (Adarsh et al., 2010 ), while there are also few examples of non-polymeric coordination compounds (Walter-Levy et al., 1973; Clarkson et al., 2001 ; Wang et al., 2005 ).

5. Synthesis and crystallization

The title compound was synthesized by heating together 0.104 g (1 mmol) malonic acid dissolved in 15 ml of propanol and 0.238 g (1 mmol) of CoCl₂·6H₂O dissolved in 5 ml of water. Violet crystals suitable for X-ray analysis were isolated after two weeks by slow evaporation of the solvent from the resulting mixture. Crystals were washed with small amounts of propanol and dried in air yielding 0.071 g (36%) of the title compound.

6. Refinement

Crystal data, data collection and structure refinement details are summarized in Table 2. H atoms bound to O atoms were located from a difference-Fourier map and constrained to ride on their parent atoms, with U_iso(H) = 1.5 U_eq(O). All C-bound H atoms were positioned geometrically and were also constrained to ride on their parent atoms, with C—H = 0.97 Å, and U_iso(H) = 1.2U_eq(C).

Table 2
Experimental details

Crystal data
Chemical formula	[Co₂(C₃H₃O₄)₂Cl₂(H₂O)₂]
M_r	430.90
Crystal system, space group	Orthorhombic, Pbca
Temperature (K)	296
a, b, c (Å)	7.568 (5), 8.879 (5), 19.168 (5)
V (Å³)	1288.0 (12)
Z	4
Radiation type	Mo Kα
μ (mm⁻¹)	3.04
Crystal size (mm)	0.20 × 0.14 × 0.07

Data collection
Diffractometer	Nonius KappaCCD
Absorption correction	Multi-scan (SADABS; Bruker, 2004 )
T_min, T_max	0.632, 0.820
No. of measured, independent and observed [I > 2σ(I)] reflections	6888, 1875, 1400
R_int	0.055
(sin θ/λ)_max (Å⁻¹)	0.704

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.046, 0.116, 1.05
No. of reflections	1875
No. of parameters	91
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	1.05, −1.00
Computer programs: COLLECT (Nonius, 2000 ), DENZO/SCALEPACK (Otwinowski & Minor, 1997 ), SHELXS97 and SHELXL97 (Sheldrick, 2008 ) and DIAMOND (Brandenburg, 2010 ).

Supporting information

CCDC reference: 1440440

Crystal structure: contains datablock I. DOI: 10.1107/S2056989015023269/wm5235sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S2056989015023269/wm5235Isup2.hkl

checkCIF report

Computing details top

Data collection: COLLECT (Nonius, 2000); cell refinement: DENZO/SCALEPACK (Otwinowski & Minor, 1997); data reduction: DENZO/SCALEPACK (Otwinowski & Minor, 1997); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: DIAMOND (Brandenburg, 2010); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Poly[diaqua(µ-2-carboxyacetato-κ³O,O':O'')(2-carboxyacetato-κO)di-µ-chlorido-cobalt(II)] top

Crystal data top

[Co₂(C₃H₃O₄)₂Cl₂(H₂O)₂]	F(000) = 856
M_r = 430.90	D_x = 2.222 Mg m⁻³
Orthorhombic, Pbca	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ac 2ab	Cell parameters from 1003 reflections
a = 7.568 (5) Å	θ = 3.4–27.6°
b = 8.879 (5) Å	µ = 3.04 mm⁻¹
c = 19.168 (5) Å	T = 296 K
V = 1288.0 (12) Å³	Block, violet
Z = 4	0.20 × 0.14 × 0.07 mm

Data collection top

Nonius KappaCCD diffractometer	1875 independent reflections
Radiation source: fine-focus sealed tube	1400 reflections with I > 2σ(I)
Horizontally mounted graphite crystal monochromator	R_int = 0.055
Detector resolution: 9 pixels mm^-1	θ_max = 30.0°, θ_min = 3.4°
φ scans and ω scans with κ offset	h = −10→10
Absorption correction: multi-scan (SADABS; Bruker, 2004)	k = −12→12
T_min = 0.632, T_max = 0.820	l = −24→26
6888 measured reflections

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)] = 0.046	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.116	H-atom parameters constrained
S = 1.05	w = 1/[σ²(F_o²) + (0.0552P)² + 0.9469P] where P = (F_o² + 2F_c²)/3
1875 reflections	(Δ/σ)_max < 0.001
91 parameters	Δρ_max = 1.05 e Å⁻³
0 restraints	Δρ_min = −1.00 e Å⁻³

Special details top

Experimental. The O-H hydrogens were located from the difference Fourier map but constrained to ride it's parent atom, with U_iso = 1.5 U_eq(parent atom). Other hydrogens were positioned geometrically and were also constrained to ride on their parent atoms, with C—H = 0.97 Å, and U_iso = 1.2 U_eq(parent atom).

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds 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 > 2sigma(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
Co1	0.57087 (6)	0.47694 (6)	0.58530 (2)	0.01449 (15)
Cl1	0.71412 (10)	0.46924 (11)	0.47183 (5)	0.0223 (2)
C1	0.4104 (4)	0.6347 (4)	0.70892 (19)	0.0177 (7)
C2	0.4303 (4)	0.7853 (4)	0.6731 (2)	0.0176 (7)
H2A	0.3323	0.7991	0.6411	0.021*
H2B	0.4237	0.8644	0.7079	0.021*
C3	0.6012 (4)	0.8016 (4)	0.63323 (18)	0.0133 (7)
O1	0.6877 (3)	0.9227 (3)	0.64044 (14)	0.0179 (5)
O2	0.5004 (3)	0.2544 (3)	0.58516 (16)	0.0276 (6)
H1O2	0.5966	0.1929	0.5746	0.041*
H2O2	0.3970	0.2004	0.5857	0.041*
O3	0.4575 (3)	0.5133 (3)	0.68488 (14)	0.0202 (6)
O4	0.3363 (4)	0.6465 (3)	0.77023 (15)	0.0321 (7)
H1O4	0.3361	0.5574	0.7994	0.048*
O5	0.6515 (3)	0.6967 (3)	0.59383 (13)	0.0175 (5)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Co1	0.0156 (2)	0.0112 (2)	0.0167 (3)	−0.00042 (16)	−0.00079 (17)	−0.00210 (19)
Cl1	0.0181 (4)	0.0284 (5)	0.0204 (4)	0.0089 (3)	0.0002 (3)	−0.0038 (4)
C1	0.0123 (13)	0.0175 (19)	0.0233 (19)	−0.0019 (12)	0.0039 (13)	0.0013 (15)
C2	0.0146 (13)	0.0125 (17)	0.0257 (19)	0.0004 (12)	0.0054 (13)	0.0009 (15)
C3	0.0148 (13)	0.0099 (16)	0.0152 (17)	0.0007 (11)	0.0005 (11)	0.0014 (13)
O1	0.0206 (11)	0.0110 (12)	0.0220 (13)	−0.0028 (9)	0.0063 (10)	−0.0034 (11)
O2	0.0171 (11)	0.0177 (15)	0.0481 (19)	−0.0021 (10)	−0.0059 (12)	−0.0016 (13)
O3	0.0274 (13)	0.0133 (13)	0.0198 (14)	−0.0018 (10)	0.0038 (10)	−0.0005 (11)
O4	0.0514 (17)	0.0192 (15)	0.0257 (15)	0.0046 (13)	0.0211 (14)	0.0029 (12)
O5	0.0213 (11)	0.0116 (12)	0.0196 (13)	−0.0021 (9)	0.0052 (10)	−0.0047 (10)

Geometric parameters (Å, º) top

Co1—O2	2.046 (3)	C2—C3	1.509 (4)
Co1—O5	2.051 (3)	C2—H2A	0.9700
Co1—O3	2.118 (3)	C2—H2B	0.9700
Co1—O1ⁱ	2.165 (3)	C3—O5	1.258 (4)
Co1—Cl1	2.4312 (12)	C3—O1	1.267 (4)
Co1—Cl1ⁱⁱ	2.4657 (16)	O1—Co1ⁱⁱⁱ	2.165 (3)
Cl1—Co1ⁱⁱ	2.4657 (16)	O2—H1O2	0.9325
C1—O3	1.225 (5)	O2—H2O2	0.9180
C1—O4	1.306 (4)	O4—H1O4	0.9698
C1—C2	1.511 (5)

O2—Co1—O5	174.98 (11)	O4—C1—C2	112.4 (3)
O2—Co1—O3	92.46 (11)	C3—C2—C1	113.6 (3)
O5—Co1—O3	84.46 (10)	C3—C2—H2A	108.8
O2—Co1—O1ⁱ	90.35 (10)	C1—C2—H2A	108.8
O5—Co1—O1ⁱ	85.50 (10)	C3—C2—H2B	108.8
O3—Co1—O1ⁱ	86.33 (10)	C1—C2—H2B	108.8
O2—Co1—Cl1	95.04 (9)	H2A—C2—H2B	107.7
O5—Co1—Cl1	88.02 (7)	O5—C3—O1	122.5 (3)
O3—Co1—Cl1	172.49 (8)	O5—C3—C2	119.5 (3)
O1ⁱ—Co1—Cl1	93.10 (8)	O1—C3—C2	118.0 (3)
O2—Co1—Cl1ⁱⁱ	87.62 (8)	C3—O1—Co1ⁱⁱⁱ	124.9 (2)
O5—Co1—Cl1ⁱⁱ	96.38 (8)	Co1—O2—H1O2	111.3
O3—Co1—Cl1ⁱⁱ	90.93 (8)	Co1—O2—H2O2	136.6
O1ⁱ—Co1—Cl1ⁱⁱ	176.52 (8)	H1O2—O2—H2O2	111.2
Cl1—Co1—Cl1ⁱⁱ	89.89 (4)	C1—O3—Co1	126.2 (3)
Co1—Cl1—Co1ⁱⁱ	90.11 (4)	C1—O4—H1O4	117.0
O3—C1—O4	122.3 (4)	C3—O5—Co1	131.5 (2)
O3—C1—C2	125.3 (3)

O2—Co1—Cl1—Co1ⁱⁱ	87.60 (8)	C2—C1—O3—Co1	−2.5 (5)
O5—Co1—Cl1—Co1ⁱⁱ	−96.39 (8)	O2—Co1—O3—C1	−158.3 (3)
O1ⁱ—Co1—Cl1—Co1ⁱⁱ	178.22 (8)	O5—Co1—O3—C1	25.7 (3)
Cl1ⁱⁱ—Co1—Cl1—Co1ⁱⁱ	0.0	O1ⁱ—Co1—O3—C1	111.5 (3)
O3—C1—C2—C3	−38.3 (5)	Cl1ⁱⁱ—Co1—O3—C1	−70.6 (3)
O4—C1—C2—C3	141.5 (3)	O1—C3—O5—Co1	166.5 (2)
C1—C2—C3—O5	46.5 (5)	C2—C3—O5—Co1	−14.4 (5)
C1—C2—C3—O1	−134.3 (4)	O3—Co1—O5—C3	−17.1 (3)
O5—C3—O1—Co1ⁱⁱⁱ	2.2 (5)	O1ⁱ—Co1—O5—C3	−103.9 (3)
C2—C3—O1—Co1ⁱⁱⁱ	−176.9 (2)	Cl1—Co1—O5—C3	162.9 (3)
O4—C1—O3—Co1	177.8 (2)	Cl1ⁱⁱ—Co1—O5—C3	73.2 (3)

Symmetry codes: (i) −x+3/2, y−1/2, z; (ii) −x+1, −y+1, −z+1; (iii) −x+3/2, y+1/2, z.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O2—H1O2···O5ⁱ	0.93	1.94	2.689 (4)	136
O2—H2O2···Cl1^iv	0.92	2.32	3.135 (3)	147
O4—H1O4···O1^v	0.97	1.67	2.629 (4)	169

Symmetry codes: (i) −x+3/2, y−1/2, z; (iv) x−1/2, −y+1/2, −z+1; (v) −x+1, y−1/2, −z+3/2.

Acknowledgements

The authors acknowledge the Algerian MESRS (Ministère de l'Enseignement Supérieur et de la Recherche Scientifique), the DGRSDT (Direction Générale de la Recherche Scientifique et du Développement Technologique) and URCHEMS for financial support.

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