catena-Poly[[aqua­glycolatocopper(II)]-μ-chlorido]

In the crystal structure of the title compound, [Cu(C₂H₃O₃)Cl(H₂O)]_n, the Cu^II ion is five-coordinate in a distorted square-pyramidal geometry. Two O atoms from a chelating glycolate anion, an O atom from a coordinated water mol­ecule and a chloride anion comprise the basal plane. A chloride ion from a neighbouring unit occupies the apical position and these Cu—Cl—Cu bridges link the aqua­glycolatocopper(II) units into one-dimensional chains along the [001] direction. These chains are connected by O—H...O and O—H...Cl hydrogen bonds, forming an infinite three-dimensional polymeric network.

Key indicators

• Single-crystal X-ray study
• T = 100 K
• Mean [sigma](C-C) = 0.002 Å
• R factor = 0.022
• wR factor = 0.058
• Data-to-parameter ratio = 25.5

checkCIF/PLATON results

No syntax errors found



Alert level B
PLAT232_ALERT_2_B Hirshfeld Test Diff (M-X)  Cu1    -   Cl1     ..      10.69 su

Alert level C
SHFSU01_ALERT_2_C  Test not performed. _refine_ls_shift/su_max and
            _refine_ls_shift/esd_max not present.
            Absolute value of the parameter shift to su ratio given   0.001
PLAT062_ALERT_4_C Rescale T(min) & T(max) by .....................       0.92
PLAT164_ALERT_4_C Nr. of Refined C-H H-Atoms in Heavy-At Struct...          2
PLAT232_ALERT_2_C Hirshfeld Test Diff (M-X)  Cu1    -   O2      ..       5.31 su
PLAT710_ALERT_4_C Delete 1-2-3 or 2-3-4 Linear Torsion Angle ... #          5
            O1W -CU1 -O1  -C1     39.60  0.30   1.555   1.555   1.555   1.555
PLAT720_ALERT_4_C Number of Unusual/Non-Standard Label(s) ........          3
PLAT764_ALERT_4_C Overcomplete CIF Bond List Detected (Rep/Expd) .       1.11 Ratio

Alert level G
ABSTM02_ALERT_3_G  When printed, the submitted absorption T values will be
            replaced by the scaled T values. Since the ratio of scaled T's
            is identical to the ratio of reported T values, the scaling
            does not imply a change to the absorption corrections used in
            the study.
            Ratio of Tmax expected/reported      0.918
            Tmax scaled      0.470 Tmin scaled      0.174

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

   0 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   3 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
   5 ALERT type 4 Improvement, methodology, query or suggestion
   0 ALERT type 5 Informative message, check

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S1. Comment

Glycolic acid (2-hydroxyethanoic acid) is a biologically active compound and has versatile binding modes for metals. (Gao et al., 2004). A number of structures of metal complexes containing the glycolate ligand have been reported (Medina et al., 2000; Prout et al.1993) with the chelating glycolate ligand coordinating to metal ions through the hydroxy and carboxy groups. In some coordination modes, the hydroxy groups of the glycolate are deprotonated (Dengel et al.,1987; Lanfranchi et al., 1993). In this paper we report the structure of a novel three dimensional polymeric chloro-bridged copper complex with glycolate and water as auxiliary ligands.

In the asymmetric unit of the title compound, the Cu^II ion is five–coordinated with a distorted square–pyramidal geometry. The basal plane is formed by atoms O1 and O2 from the glycolate ligand in a chelating mode, a water oxygen and a chloride anion. Cl^- anions from neighbouring molecules link the [C₂H₅ClCuO₄] units into polymeric chains along the [0 0 1] direction. The five membered ring [Cu1—O2—C2—C1—O1] is essentially planar with the maximum deviation from planarity being 0.008 (2)Å for the atom O1. The atom Cu1 is displaced by -0.1603 (1)Å out of the basal plane of the square pyramid towards atom Cl1.

The molecules are linked into one dimensional polymeric chains along the [0 0 1] direction through bridging chloride ions. Adjacent chains are interconnected by O—H···O, and O—H···Cl hydrogen bonds to form an infinite three dimensional polymeric network.

Related literature

For background to the coordination chemistry of glycolic acid, see: Gao et al. (2004). For related structures, see: Dengel et al. (1987); Lanfranchi et al. (1993); Medina et al. (2000); Prout et al. (1993).

S2. Experimental

Equimolar amounts of glycolic acid and CuCl₂ were dissolved in ethanol. The solution was refluxed at a temperature of 333°K for a period of 48 h. The clear blue colour solution was allowed to evaporate slowly yielding blue crystals of (I) after one month.

S3. Refinement

All the hydrogen atoms were located from the Fourier map and were allowed to refine freely.

Computing details

Data collection: APEX2 (Bruker, 2005); cell refinement: APEX2 (Bruker, 2005); data reduction: SAINT (Bruker, 2005); 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) and PLATON (Spek, 2003).

Figures

	Fig. 1. The molecular structure of the title compound, showing 50% probability displacement ellipsoids and the atomic numbering scheme. Symmetry code for atoms labelled A: x, -y + 1/2, z + 1/2.
	Fig. 2. The crystal packing of the title compound, viewed along the a axis, showing a polymeric chain along the c axis.

catena-Poly[[aquaglycolatocopper(II)]-µ-chlorido]

Crystal data

[Cu(C2H3O3)Cl(H2O)]	F(000) = 380
Mr = 192.05	Dx = 2.358 Mg m^−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 6364 reflections
a = 7.6296 (2) Å	θ = 2.8–41.4°
b = 10.0896 (3) Å	µ = 4.45 mm^−1
c = 7.4603 (2) Å	T = 100 K
β = 109.632 (1)°	Block, blue
V = 540.91 (3) Å^3	0.56 × 0.19 × 0.17 mm
Z = 4

Data collection

Bruker SMART APEXII CCD area-detector diffractometer	2372 independent reflections
Radiation source: fine-focus sealed tube	2147 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.025
ϕ and ω scans	θmax = 35.0°, θmin = 2.8°
Absorption correction: multi-scan (SADABS; Bruker, 2005)	h = −12→12
Tmin = 0.189, Tmax = 0.512	k = −15→16
10874 measured reflections	l = −12→12

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)] = 0.022	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.058	All H-atom parameters refined
S = 1.05	w = 1/[σ^2(Fo^2) + (0.035P)^2 + 0.0909P] where P = (Fo^2 + 2Fc^2)/3
2372 reflections	(Δ/σ)max < 0.001
93 parameters	Δρmax = 0.80 e Å^−3
0 restraints	Δρmin = −0.66 e Å^−3

Special details

Experimental. The data was collected with the Oxford Cyrosystem Cobra low-temperature attachment.

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	0.709943 (18)	0.143386 (14)	0.84591 (2)	0.01140 (5)
Cl1	0.55544 (4)	0.22147 (3)	0.48054 (4)	0.01285 (6)
O1	0.92698 (11)	0.26130 (9)	0.90217 (13)	0.01339 (15)
O2	0.87233 (11)	0.01710 (9)	0.78289 (13)	0.01408 (15)
O3	1.15672 (12)	−0.01023 (10)	0.76906 (14)	0.01787 (17)
C1	1.08255 (15)	0.20052 (12)	0.86756 (17)	0.01349 (19)
C2	1.03389 (15)	0.05935 (12)	0.80059 (16)	0.01302 (18)
O1W	0.52646 (12)	0.00559 (10)	0.80898 (13)	0.01492 (16)
H1A	1.114 (3)	0.2483 (19)	0.773 (3)	0.017 (4)*
H1B	1.183 (3)	0.2001 (19)	0.981 (3)	0.014 (4)*
H1W1	0.526 (3)	−0.050 (3)	0.740 (3)	0.033 (6)*
H2W1	0.422 (3)	0.026 (2)	0.809 (3)	0.034 (6)*
H1O1	0.904 (3)	0.331 (2)	0.849 (3)	0.025 (5)*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Cu1	0.01055 (7)	0.00927 (8)	0.01456 (7)	−0.00050 (4)	0.00446 (5)	−0.00081 (4)
Cl1	0.01344 (10)	0.01174 (12)	0.01357 (10)	−0.00079 (9)	0.00481 (8)	0.00024 (8)
O1	0.0120 (3)	0.0100 (4)	0.0183 (4)	0.0004 (3)	0.0053 (3)	0.0003 (3)
O2	0.0115 (3)	0.0117 (4)	0.0188 (4)	−0.0006 (3)	0.0049 (3)	−0.0012 (3)
O3	0.0139 (3)	0.0142 (4)	0.0264 (4)	0.0003 (3)	0.0078 (3)	−0.0043 (3)
C1	0.0127 (4)	0.0117 (5)	0.0170 (4)	0.0001 (4)	0.0063 (4)	−0.0010 (4)
C2	0.0119 (4)	0.0122 (5)	0.0143 (4)	0.0003 (4)	0.0034 (3)	0.0009 (4)
O1W	0.0141 (3)	0.0129 (4)	0.0193 (4)	−0.0030 (3)	0.0076 (3)	−0.0037 (3)

Geometric parameters (Å, º)

Cu1—O1W	1.9260 (9)	O2—C2	1.2686 (13)
Cu1—O2	1.9419 (8)	O3—C2	1.2548 (14)
Cu1—O1	1.9664 (9)	C1—C2	1.5138 (17)
Cu1—Cl1^i	2.2480 (3)	C1—H1A	0.951 (19)
Cu1—Cl1	2.6983 (3)	C1—H1B	0.928 (19)
Cl1—Cu1^ii	2.2479 (3)	O1W—H1W1	0.76 (3)
O1—C1	1.4344 (14)	O1W—H2W1	0.82 (2)
O1—H1O1	0.80 (2)
O1W—Cu1—O2	89.08 (4)	C2—O2—Cu1	115.53 (8)
O1W—Cu1—O1	170.67 (4)	O1—C1—C2	109.61 (9)
O2—Cu1—O1	83.61 (4)	O1—C1—H1A	110.3 (11)
O1W—Cu1—Cl1^i	92.11 (3)	C2—C1—H1A	109.0 (12)
O2—Cu1—Cl1^i	168.29 (3)	O1—C1—H1B	108.4 (11)
O1—Cu1—Cl1^i	93.90 (3)	C2—C1—H1B	109.3 (12)
O1W—Cu1—Cl1	90.94 (3)	H1A—C1—H1B	110.2 (16)
O2—Cu1—Cl1	92.56 (3)	O3—C2—O2	123.59 (11)
O1—Cu1—Cl1	95.15 (3)	O3—C2—C1	118.20 (10)
Cl1^i—Cu1—Cl1	99.065 (9)	O2—C2—C1	118.20 (10)
Cu1^ii—Cl1—Cu1	120.780 (12)	Cu1—O1W—H1W1	118.1 (17)
C1—O1—Cu1	113.04 (7)	Cu1—O1W—H2W1	118.3 (16)
C1—O1—H1O1	109.9 (16)	H1W1—O1W—H2W1	114 (2)
Cu1—O1—H1O1	113.7 (16)
O1W—Cu1—Cl1—Cu1^ii	−165.23 (3)	O1—Cu1—O2—C2	−0.62 (8)
O2—Cu1—Cl1—Cu1^ii	−76.11 (3)	Cl1^i—Cu1—O2—C2	−78.90 (16)
O1—Cu1—Cl1—Cu1^ii	7.70 (3)	Cl1—Cu1—O2—C2	94.27 (8)
Cl1^i—Cu1—Cl1—Cu1^ii	102.489 (19)	Cu1—O1—C1—C2	−1.27 (11)
O1W—Cu1—O1—C1	39.6 (3)	Cu1—O2—C2—O3	178.65 (9)
O2—Cu1—O1—C1	1.08 (8)	Cu1—O2—C2—C1	0.04 (13)
Cl1^i—Cu1—O1—C1	169.58 (7)	O1—C1—C2—O3	−177.86 (10)
Cl1—Cu1—O1—C1	−90.94 (7)	O1—C1—C2—O2	0.83 (15)
O1W—Cu1—O2—C2	−174.83 (8)

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

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O1W—H1W1···Cl1^iii	0.76 (3)	2.32 (3)	3.0654 (10)	166 (2)
O1W—H2W1···O3^iv	0.82 (2)	1.98 (2)	2.7400 (12)	153 (2)
O1—H1O1···O3^v	0.80 (2)	1.81 (2)	2.6086 (13)	177 (2)

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