Poly[diaqua­(μ₃-succinato)cadmium(II)]

Abstract

The title compound, [Cd(C₄H₄O₄)(H₂O)₂]_n, has been synthesized under hydro­thermal conditions. The asymmetric unit consists of one Cd²⁺ cation, one succinate anion and two aqua ligands. The Cd atoms present a distorted penta­gonal bipyramidal coordination and are bridged into layers parallel to (201) by succinate ligands.

Related literature

For different bridging modes in succinato complexes, see: Ng (1998 ▶); Rastsvetaeva et al. (1996 ▶); Brusau et al. (2000 ▶); He et al. (2006 ▶); He et al. (2007 ▶). For geometrical comparisons with related compounds, see Huo et al. (2005 ▶); Zhuo et al. (2006 ▶).

Experimental

Crystal data

• [Cd(C₄H₄O₄)(H₂O)₂]

• M _r = 264.51

• Monoclinic,

• a = 7.7130 (15) Å

• b = 12.231 (2) Å

• c = 8.0560 (16) Å

• β = 94.71 (3)°

• V = 757.4 (2) ų

• Z = 4

• Mo Kα radiation

• μ = 2.87 mm⁻¹

• T = 293 K

• 0.40 × 0.30 × 0.21 mm

Data collection

• Bruker SMART CCD area-detector diffractometer

• Absorption correction: multi-scan (SADABS; Bruker, 1998 ▶) T _min = 0.35, T _max = 0.55

• 6371 measured reflections

• 1409 independent reflections

• 1335 reflections with I > 2σ(I)

• R _int = 0.028

Refinement

• R[F ² > 2σ(F ²)] = 0.023

• wR(F ²) = 0.053

• S = 1.05

• 1409 reflections

• 116 parameters

• 6 restraints

• H atoms treated by a mixture of independent and constrained refinement

• Δρ_max = 0.40 e Å⁻³

• Δρ_min = −0.68 e Å⁻³

Data collection: SMART (Bruker, 1998 ▶); cell refinement: SAINT (Bruker, 1998 ▶); data reduction: SAINT; 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.

Supplementary Material

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Table 1. Selected bond lengths (Å).

Cd1—O4i	2.255 (2)
Cd1—O2	2.284 (2)
Cd1—O6	2.302 (3)
Cd1—O4ii	2.316 (2)
Cd1—O5	2.329 (3)
Cd1—O1	2.389 (2)
Cd1—O3i	2.690 (2)

Symmetry codes: (i) ; (ii) .

supplementary crystallographic information

Comment

The succinate dianion has been used as a bridging ligand in the preparation of multinuclear metal complexes. A variety of bridging modes have been found (Ng,1998; Rastsvetaeva et al., 1996; Brusau et al., 2000; He et al., 2006; He et al., 2007). We report herein the synthesis and crystal stucture of a new succinate complex [Cd(C₄H₄O₄)(H₂O)₂] (I).

The asymmetric unit consists of one Cd²⁺ cation, one succinate anion and two aqua ligands (Fig. 1). The Cd atom is coordinated by seven O atoms of three succinate anions and two aqua ligand, forming a distorted pentagonal bipyramidal coordination geometry (Table 1), with Cd—O bond lengths which agree well with those observed in analogous complexes (Huo et al., 2005; Zhuo et al., 2006). Cd atoms are bridged by succinate ligands into a two-dimensional layer (Fig. 2).

Experimental

Cd(NO₃)₂.4H₂O (0.5 mmol, 0.154 g), succinic acid (0.5 mmol, 0.059 g), sodium hydroxide (1 mmol, 0.04 g) and water (12 ml) were placed in a 23-ml Teflon-lined Parr bomb. The bomb was heated at 453 K for 3 d. The colourless block-shapped crystals were filtered off and washed with water and acetone (yield 45%, based on Cd).

Refinement

Water H atoms were located in a difference Fourier map and refined with restrained O-H (0.85 (1)Å) and free U_iso(H). H atoms on C atom were positoned geometrically and refined using a riding model, with C—H = 0.97 Å.

Figures

Fig. 1.

A view of the molecular structure of (I) with the atom-numbering scheme and 30% displacement ellipsoids. Atoms with the suffix A and B are generated by the symmetry operations x + 1, -y + 3/2, z + 1/2 and -x + 2, -y + 1, -z + 2, respectively.

Fig. 2.

The 2-D layer structure of compound (I) (H atoms of methylenes are omitted for clarity).

Crystal data

[Cd(C4H4O4)(H2O)2]	F(000) = 512.0
Mr = 264.51	Dx = 2.32 Mg m−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 2567 reflections
a = 7.7130 (15) Å	θ = 2.6–25.5°
b = 12.231 (2) Å	µ = 2.87 mm−1
c = 8.0560 (16) Å	T = 293 K
β = 94.71 (3)°	Block, colorless
V = 757.4 (2) Å3	0.40 × 0.30 × 0.21 mm
Z = 4

Data collection

Bruker SMART CD area-detector diffractometer	1409 independent reflections
Radiation source: fine-focus sealed tube	1335 reflections with I > 2σ(I)
graphite	Rint = 0.028
φ and ω scans	θmax = 25.5°, θmin = 3.0°
Absorption correction: multi-scan (SADABS; Bruker, 1998)	h = −9→9
Tmin = 0.35, Tmax = 0.55	k = −14→14
6371 measured reflections	l = −9→9

Refinement

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)] = 0.023	Hydrogen site location: constr
wR(F2) = 0.053	H atoms treated by a mixture of independent and constrained refinement
S = 1.05	w = 1/[σ2(Fo2) + (0.0207P)2 + 1.5P] where P = (Fo2 + 2Fc2)/3
1409 reflections	(Δ/σ)max < 0.001
116 parameters	Δρmax = 0.40 e Å−3
6 restraints	Δρmin = −0.68 e Å−3

Special details

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 > 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
Cd1	0.17614 (3)	0.587427 (19)	0.08353 (3)	0.02570 (10)
C1	0.4820 (4)	0.6353 (3)	0.2526 (4)	0.0274 (7)
C2	0.6501 (5)	0.6626 (3)	0.3501 (6)	0.0454 (10)
H2A	0.6471	0.6327	0.4613	0.055*
H2B	0.7436	0.6262	0.2983	0.055*
C3	0.6922 (4)	0.7799 (3)	0.3648 (5)	0.0349 (9)
H3A	0.6046	0.8150	0.4262	0.042*
H3B	0.6840	0.8113	0.2538	0.042*
C4	0.8675 (4)	0.8072 (3)	0.4482 (4)	0.0252 (7)
O1	0.4603 (3)	0.5387 (2)	0.2005 (3)	0.0367 (6)
O2	0.3664 (3)	0.70570 (19)	0.2216 (3)	0.0352 (6)
O3	0.9815 (3)	0.7385 (2)	0.4838 (3)	0.0399 (6)
O4	0.8946 (3)	0.90780 (18)	0.4832 (3)	0.0307 (6)
O5	0.0710 (4)	0.5424 (2)	0.3376 (3)	0.0402 (6)
H5A	−0.012 (5)	0.499 (3)	0.325 (6)	0.072 (18)*
H5B	0.047 (5)	0.598 (2)	0.392 (5)	0.056 (15)*
O6	0.2576 (3)	0.5909 (2)	−0.1850 (3)	0.0332 (6)
H6A	0.348 (4)	0.553 (3)	−0.197 (5)	0.044 (12)*
H6B	0.278 (5)	0.6562 (17)	−0.213 (5)	0.051 (13)*

Atomic displacement parameters (Ų)

	U11	U22	U33	U12	U13	U23
Cd1	0.01635 (14)	0.02632 (15)	0.03318 (16)	−0.00248 (9)	−0.00550 (10)	−0.00305 (10)
C1	0.0181 (16)	0.0294 (18)	0.0342 (18)	−0.0041 (14)	−0.0016 (14)	−0.0046 (15)
C2	0.032 (2)	0.034 (2)	0.065 (3)	−0.0035 (17)	−0.0250 (19)	0.0000 (19)
C3	0.0231 (18)	0.0299 (19)	0.049 (2)	−0.0034 (15)	−0.0132 (16)	−0.0034 (16)
C4	0.0213 (16)	0.0263 (18)	0.0278 (18)	−0.0025 (14)	−0.0003 (13)	−0.0029 (14)
O1	0.0220 (12)	0.0292 (14)	0.0572 (17)	0.0006 (10)	−0.0056 (11)	−0.0134 (12)
O2	0.0245 (13)	0.0274 (13)	0.0512 (16)	0.0008 (10)	−0.0117 (11)	−0.0102 (11)
O3	0.0264 (13)	0.0286 (13)	0.0619 (18)	0.0039 (11)	−0.0132 (12)	−0.0085 (12)
O4	0.0229 (12)	0.0228 (12)	0.0448 (15)	−0.0029 (9)	−0.0078 (11)	−0.0017 (10)
O5	0.0414 (16)	0.0419 (17)	0.0377 (16)	0.0015 (14)	0.0054 (12)	−0.0026 (13)
O6	0.0306 (14)	0.0266 (14)	0.0432 (15)	0.0036 (11)	0.0070 (11)	0.0052 (11)

Geometric parameters (Å, °)

Cd1—O4i	2.255 (2)	C2—H2A	0.9700
Cd1—O2	2.284 (2)	C2—H2B	0.9700
Cd1—O6	2.302 (3)	C3—C4	1.498 (4)
Cd1—O4ii	2.316 (2)	C3—H3A	0.9700
Cd1—O5	2.329 (3)	C3—H3B	0.9700
Cd1—O1	2.389 (2)	C4—O3	1.233 (4)
Cd1—O3i	2.690 (2)	C4—O4	1.275 (4)
C1—O2	1.250 (4)	O5—H5B	0.84 (3)
C1—O1	1.260 (4)	O5—H5A	0.84 (3)
C1—C2	1.498 (5)	O6—H6A	0.85 (3)
C2—C3	1.474 (5)	O6—H6B	0.85 (3)
O4i—Cd1—O2	136.02 (8)	C1—C2—H2B	108.3
O4i—Cd1—O6	89.54 (10)	H2A—C2—H2B	107.4
O2—Cd1—O6	103.41 (10)	C2—C3—C4	116.0 (3)
O4i—Cd1—O4ii	74.92 (9)	C2—C3—H3A	108.3
O2—Cd1—O4ii	147.52 (8)	C4—C3—H3A	108.3
O6—Cd1—O4ii	82.91 (9)	C2—C3—H3B	108.3
O4i—Cd1—O5	85.77 (10)	C4—C3—H3B	108.3
O2—Cd1—O5	88.74 (10)	H3A—C3—H3B	107.4
O6—Cd1—O5	166.39 (10)	O3—C4—O4	120.4 (3)
O4ii—Cd1—O5	83.54 (10)	O3—C4—C3	123.5 (3)
O4i—Cd1—O1	166.71 (8)	O4—C4—C3	116.1 (3)
O2—Cd1—O1	55.52 (8)	C1—O1—Cd1	89.42 (19)
O6—Cd1—O1	93.60 (10)	C1—O2—Cd1	94.6 (2)
O4ii—Cd1—O1	92.64 (8)	C4—O4—Cd1iii	103.8 (2)
O5—Cd1—O1	88.23 (10)	C4—O4—Cd1iv	146.3 (2)
O2—C1—O1	120.4 (3)	Cd1iii—O4—Cd1iv	105.08 (9)
O2—C1—C2	121.6 (3)	Cd1—O5—H5B	112 (3)
O1—C1—C2	118.0 (3)	Cd1—O5—H5A	111 (3)
C3—C2—C1	115.8 (3)	H5B—O5—H5A	112 (3)
C3—C2—H2A	108.3	Cd1—O6—H6A	113 (3)
C1—C2—H2A	108.3	Cd1—O6—H6B	110 (3)
C3—C2—H2B	108.3	H6A—O6—H6B	108 (3)
O2—C1—C2—C3	−16.9 (6)	O1—C1—O2—Cd1	2.1 (4)
O1—C1—C2—C3	162.3 (4)	C2—C1—O2—Cd1	−178.7 (3)
C1—C2—C3—C4	−174.5 (3)	O4i—Cd1—O2—C1	170.1 (2)
C2—C3—C4—O3	9.5 (6)	O6—Cd1—O2—C1	−86.3 (2)
C2—C3—C4—O4	−170.0 (4)	O4ii—Cd1—O2—C1	11.7 (3)
O2—C1—O1—Cd1	−2.0 (3)	O5—Cd1—O2—C1	87.5 (2)
C2—C1—O1—Cd1	178.7 (3)	O1—Cd1—O2—C1	−1.2 (2)
O4i—Cd1—O1—C1	−151.7 (4)	O3—C4—O4—Cd1iii	5.3 (4)
O2—Cd1—O1—C1	1.2 (2)	C3—C4—O4—Cd1iii	−175.2 (3)
O6—Cd1—O1—C1	105.0 (2)	O3—C4—O4—Cd1iv	153.9 (3)
O4ii—Cd1—O1—C1	−172.0 (2)	C3—C4—O4—Cd1iv	−26.5 (6)
O5—Cd1—O1—C1	−88.5 (2)

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