Poly[trans-diaqua­bis[μ-3-(3-pyrid­yl)propionato-κ2N,O]cadmium(II)]

Jang, Y.O.; Lee, S.W.

doi:10.1107/S1600536810005222

metal-organic compounds

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Volume 66| Part 3| March 2010| Page m293

doi:10.1107/S1600536810005222

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Poly[trans-diaquabis[μ-3-(3-pyridyl)propionato-κ²N,O]cadmium(II)]

Young Ok Jang ^a and Soon W. Lee ^a ^*

^aDepartment of Chemistry (BK21), Sungkyunkwan University, Natural Science Campus, Suwon 440-746, Republic of Korea
^*Correspondence e-mail: soonwlee@skku.edu

(Received 2 February 2010; accepted 9 February 2010; online 13 February 2010)

The title compound [Cd(L)₂(H₂O)₂]_n (L = 3-pyridinepropionic acid, C₈H₈NO₂), is a two-dimensional coordination polymer in which the Cd^II ion lies on an inversion center and is coordinated in a slightly distorted octahedral environment. The aqua H atoms are involved in intermolecular O–H⋯O hydrogen bonds, which extend the two-dimensional structure to a three-dimensional architecture. The Cd⋯Cd separation within a layer is 9.0031 (1) Å.

Related literature

For the isostructural zinc analog, see: Wang et al. (2006 ) and for the cobalt and nickel analogs, see: Martin et al. (2007 ). For background information on coordination polymers, see: Batten et al. (2009 ); Lu (2003 ); Perry et al. (2009 ); Robin & Fromm (2006 ). For coordination polymers based on pyridine carboxylates, see: Huh & Lee (2006 , 2007 , 2008 ); Kim et al. (2007 ); Min et al. (2001 , 2002 ); Min & Lee (2002 ).

Experimental

Crystal data

[Cd(C₈H₈NO₂)₂(H₂O)₂]
M_r = 448.74
Monoclinic, P 2₁ /n
a = 9.6934 (4) Å
b = 8.9082 (4) Å
c = 10.1199 (5) Å
β = 104.309 (2)°
V = 846.75 (7) Å³
Z = 2
Mo Kα radiation
μ = 1.33 mm⁻¹
T = 296 K
0.42 × 0.38 × 0.28 mm

Data collection

Bruker SMART CCD diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 1996 ) T_min = 0.606, T_max = 0.708
12941 measured reflections
2113 independent reflections
1911 reflections with I > 2σ(I)
R_int = 0.021

Refinement

R[F² > 2σ(F²)] = 0.016
wR(F²) = 0.042
S = 1.05
2113 reflections
155 parameters
All H-atom parameters refined
Δρ_max = 0.30 e Å⁻³
Δρ_min = −0.22 e Å⁻³

Table 1
Selected geometric parameters (Å, °)

Cd1—O3ⁱ	2.2704 (9)
Cd1—O1	2.3306 (11)
Cd1—N1	2.3374 (10)

O3ⁱ—Cd1—O1	86.35 (4)
O3ⁱ—Cd1—N1ⁱⁱ	91.31 (4)
O1—Cd1—N1	89.58 (4)
Symmetry codes: (i) $[-x+{\script{1\over 2}}, y-{\script{1\over 2}}, -z+{\script{1\over 2}}]$ ; (ii) -x+1, -y, -z.

Table 2
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O1—HO1B⋯O2ⁱⁱⁱ	0.83 (3)	2.01 (3)	2.8361 (16)	174 (2)
O1—HO1A⋯O2^iv	0.88 (2)	1.94 (2)	2.7546 (17)	155 (2)
Symmetry codes: (iii) -x+1, -y, -z+1; (iv) $[x+{\script{1\over 2}}, -y+{\script{1\over 2}}, z-{\script{1\over 2}}]$ .

Data collection: SMART (Bruker, 1997 ); cell refinement: SAINT (Bruker, 1997); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008 ); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL software used to prepare material for publication: SHELXTL.

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536810005222/lh2993sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536810005222/lh2993Isup2.hkl

checkCIF report

Comment top

Coordination polymers have gained attention due to their desirable properties applicable to size-selective adsorption, gas storage, host–guest recognition, catalysis, and photoluminescence (Batten et al., 2009; Perry IV et al., 2009; Robin & Fromm, 2006). We have been continually interested in the preparation, structures, and properties of coordination polymers based on the linking ligands of pyridine carboxylate derivatives, in which the carboxylate groups are directly attached to the pyridine ring (Huh & Lee, 2006; Huh & Lee, 2007; Huh & Lee, 2008; Kim et al., 2007; Min et al., 2001; Min et al., 2002; Min & Lee, 2002).

Linking ligands containing both N-donors and O-donors are frequently used for the construction of coordination polymers (Lu, 2003). In particular, silver, copper, zinc, cobalt, and nickel coordination polymers containing 3-pyridinepropionic acid as a linking ligand have been reported (Wang et al., 2006; Martin et al., 2007). This ligand has an enthylene (–CH₂–CH₂–) spacer between the pyridyl and carboxylate groups and therefore is flexible. As an extension of our study, we investigated the preparation of cadmium coordination polymers by employing this ligand.

The title compound is isostructural with the zinc (Wang et al., 2006), cobalt, and nickel (Martin et al., 2007) analogs with the empirical formula [Cd(L)₂(H₂O)₂] (L = 3-pyridinepropionic acid). The local coordination environment around the Cd atom and the atom-numbering scheme is shown in Fig. 1. The asymmetric unit consists of one half Cd^II ion, one L ligand, and one aqua ligand. The Cd^II ion lies on a crystallographic inversion center, and the remaining atoms occupy general positions. The coordination environment of the Cd^II ion is slightly-distorted octahedral. The monomer units [Cd(L)₂(H₂O)₂] are linked by covalent bonds (Cd–N and Cd–O) to form a 2-D layer approximately in the (101) plane (Fig. 2) and then extended into a 3-D architecture by hydrogen bonding. Two carboxylate O atoms (O2 and O3) act differently. Whereas O2 acts as a H-bond acceptor to the aqua ligands in the neighboring units, O3 is coordinated to the Cd metal to contribute to the formation of the 2-D layer, in which the Cd···Cd separation is 9.0031 (1) Å.

Related literature top

For the isostructural zinc analog, see: Wang et al. (2006) and for the cobalt and nickel analogs, see: Martin et al. (2007). For background information on coordination polymers, see: Batten et al. (2009); Lu (2003); Perry et al. (2009); Robin & Fromm (2006). For coordination polymers based on pyridine carboxylates, see: Huh & Lee (2006, 2007, 2008); Kim et al. (2007); Min et al. (2001, 2002); Min & Lee (2002).

Experimental top

A mixture of 3-pyridinepropionic acid (0.98 g, 6.5 mmol), [Cd(NO₃)₂]6(H₂O) (1 g, 3.2 mmol), NaOH (6.5 mmol), and H₂O (6 ml) was heated at 453 K for 2 days in a 23 ml Teflon-lined stainless-steel autoclave and then cooled slowly to room temperature to obtain pale yellow crystals. The product was collected by filtration, washed with H₂O (3 × 10 ml) and ethanol (5 × 10 ml), and then air-dried. (1.18 g, 2.6 mmol, 82%). mp: 538–540 K. IR (KBr, cm^-1): 3199 (s), 2173 (w), 1606 (s), 1302 (w), 1247 (w), 1201 (w), 1117 (m), 1047 (m), 961 (s), 607 (s)

Computing details top

Data collection: SMART (Bruker, 1997); cell refinement: SAINT (Bruker, 1997); data reduction: SAINT (Bruker, 1997); 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).

Figures top

	Fig. 1. Local coordination environment around the Cd metal in the title compound showing 50% probability displacement ellipsoids (symmetry codes: (A) -x + 1, -y, -z, (B) -x + 1/2, y - 1/2, -z + 1/2, (C) x + 1/2, -y + 1/2, z - 1/2.
	Fig. 2. Packing diagram of the title compound, showing a two-dimensional network.

Poly[trans-diaquabis[µ-3-(3-pyridyl)propionato- κ²N,O]cadmium(II)] top

Crystal data top

[Cd(C₈H₈NO₂)₂(H₂O)₂]	F(000) = 452
M_r = 448.74	D_x = 1.760 Mg m⁻³
Monoclinic, P2₁/n	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2yn	Cell parameters from 8598 reflections
a = 9.6934 (4) Å	θ = 2.6–28.4°
b = 8.9082 (4) Å	µ = 1.33 mm⁻¹
c = 10.1199 (5) Å	T = 296 K
β = 104.309 (2)°	Block, colourless
V = 846.75 (7) Å³	0.42 × 0.38 × 0.28 mm
Z = 2

Data collection top

Bruker SMART CCD diffractometer	2113 independent reflections
Radiation source: sealed tube	1911 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.021
ϕ and ω scans	θ_max = 28.4°, θ_min = 3.1°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	h = −12→12
T_min = 0.606, T_max = 0.708	k = −11→11
12941 measured reflections	l = −13→13

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)] = 0.016	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.042	All H-atom parameters refined
S = 1.05	w = 1/[σ²(F_o²) + (0.0233P)² + 0.1949P] where P = (F_o² + 2F_c²)/3
2113 reflections	(Δ/σ)_max = 0.001
155 parameters	Δρ_max = 0.30 e Å⁻³
0 restraints	Δρ_min = −0.22 e Å⁻³

Crystal data top

[Cd(C₈H₈NO₂)₂(H₂O)₂]	V = 846.75 (7) Å³
M_r = 448.74	Z = 2
Monoclinic, P2₁/n	Mo Kα radiation
a = 9.6934 (4) Å	µ = 1.33 mm⁻¹
b = 8.9082 (4) Å	T = 296 K
c = 10.1199 (5) Å	0.42 × 0.38 × 0.28 mm
β = 104.309 (2)°

Data collection top

Bruker SMART CCD diffractometer	2113 independent reflections
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	1911 reflections with I > 2σ(I)
T_min = 0.606, T_max = 0.708	R_int = 0.021
12941 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.016	0 restraints
wR(F²) = 0.042	All H-atom parameters refined
S = 1.05	Δρ_max = 0.30 e Å⁻³
2113 reflections	Δρ_min = −0.22 e Å⁻³
155 parameters

Special details top

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 (Å²) top

	x	y	z	U_iso*/U_eq
Cd1	0.5000	0.0000	0.0000	0.02437 (5)
N1	0.28876 (11)	0.07564 (12)	0.05233 (11)	0.0301 (2)
O1	0.61972 (13)	0.02896 (15)	0.22844 (12)	0.0382 (2)
O2	0.21558 (10)	0.21211 (11)	0.63186 (10)	0.0359 (2)
O3	0.04577 (10)	0.26152 (10)	0.44405 (10)	0.0352 (2)
C1	0.20346 (15)	0.17483 (15)	−0.02640 (14)	0.0329 (3)
C2	0.07951 (16)	0.22538 (17)	0.00161 (16)	0.0379 (3)
C3	0.04061 (15)	0.16952 (16)	0.11451 (15)	0.0357 (3)
C4	0.12544 (13)	0.06336 (15)	0.19621 (13)	0.0284 (3)
C5	0.24972 (16)	0.02120 (15)	0.16092 (16)	0.0303 (3)
C6	0.08326 (19)	−0.01072 (15)	0.31409 (17)	0.0345 (3)
C7	0.17242 (17)	0.03087 (17)	0.45527 (15)	0.0325 (3)
C8	0.14245 (13)	0.18100 (13)	0.51422 (13)	0.0260 (2)
H1	0.2335 (18)	0.208 (2)	−0.1008 (18)	0.042 (4)*
H2	0.0224 (18)	0.296 (2)	−0.0590 (18)	0.043 (4)*
H3	−0.0467 (19)	0.199 (2)	0.1376 (18)	0.050 (5)*
H5	0.314 (2)	−0.048 (2)	0.2165 (19)	0.044 (5)*
H6A	−0.022 (2)	0.0146 (17)	0.302 (2)	0.045 (6)*
H6B	0.0908 (17)	−0.1217 (19)	0.3076 (17)	0.039 (4)*
H7A	0.274 (3)	0.037 (3)	0.460 (2)	0.059 (6)*
H7B	0.158 (2)	−0.041 (2)	0.525 (2)	0.045 (5)*
HO1A	0.673 (2)	0.105 (3)	0.217 (2)	0.066 (7)*
HO1B	0.672 (3)	−0.041 (3)	0.266 (3)	0.065 (7)*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Cd1	0.02423 (8)	0.02733 (8)	0.02284 (8)	−0.00074 (4)	0.00826 (5)	−0.00185 (4)
N1	0.0303 (5)	0.0323 (6)	0.0310 (6)	0.0030 (4)	0.0137 (4)	0.0022 (4)
O1	0.0427 (6)	0.0401 (6)	0.0278 (5)	−0.0014 (5)	0.0011 (5)	−0.0019 (4)
O2	0.0375 (5)	0.0343 (5)	0.0338 (5)	0.0007 (4)	0.0047 (4)	−0.0022 (4)
O3	0.0369 (5)	0.0296 (5)	0.0372 (5)	0.0071 (4)	0.0055 (4)	−0.0010 (4)
C1	0.0388 (7)	0.0314 (6)	0.0303 (7)	0.0007 (5)	0.0120 (6)	0.0035 (5)
C2	0.0378 (7)	0.0357 (7)	0.0387 (8)	0.0090 (6)	0.0064 (6)	0.0053 (6)
C3	0.0293 (6)	0.0380 (7)	0.0413 (8)	0.0047 (5)	0.0119 (6)	−0.0040 (6)
C4	0.0309 (6)	0.0288 (6)	0.0281 (6)	−0.0039 (5)	0.0120 (5)	−0.0049 (5)
C5	0.0317 (7)	0.0316 (7)	0.0295 (7)	0.0043 (5)	0.0114 (6)	0.0036 (5)
C6	0.0407 (8)	0.0357 (8)	0.0318 (8)	−0.0082 (5)	0.0178 (6)	−0.0043 (5)
C7	0.0385 (8)	0.0323 (6)	0.0286 (7)	0.0063 (6)	0.0120 (6)	0.0010 (5)
C8	0.0265 (6)	0.0252 (6)	0.0294 (6)	−0.0013 (4)	0.0126 (5)	0.0024 (5)

Geometric parameters (Å, º) top

Cd1—O3ⁱ	2.2704 (9)	C1—H1	0.919 (18)
Cd1—O3ⁱⁱ	2.2705 (9)	C2—C3	1.381 (2)
Cd1—O1	2.3306 (11)	C2—H2	0.954 (17)
Cd1—O1ⁱⁱⁱ	2.3306 (11)	C3—C4	1.385 (2)
Cd1—N1ⁱⁱⁱ	2.3374 (10)	C3—H3	0.969 (18)
Cd1—N1	2.3374 (10)	C4—C5	1.3902 (18)
N1—C1	1.3318 (17)	C4—C6	1.5055 (19)
N1—C5	1.3385 (18)	C5—H5	0.96 (2)
O1—HO1A	0.88 (2)	C6—C7	1.522 (2)
O1—HO1B	0.83 (3)	C6—H6A	1.03 (2)
O2—C8	1.2568 (15)	C6—H6B	0.995 (17)
O3—C8	1.2522 (15)	C7—C8	1.5213 (19)
O3—Cd1^iv	2.2705 (9)	C7—H7A	0.98 (2)
C1—C2	1.3766 (19)	C7—H7B	0.99 (2)

O3ⁱ—Cd1—O3ⁱⁱ	180.0	C1—C2—H2	118.7 (11)
O3ⁱ—Cd1—O1	86.35 (4)	C3—C2—H2	122.4 (11)
O3ⁱⁱ—Cd1—O1	93.65 (4)	C2—C3—C4	119.78 (12)
O3ⁱ—Cd1—O1ⁱⁱⁱ	93.65 (4)	C2—C3—H3	122.3 (11)
O3ⁱⁱ—Cd1—O1ⁱⁱⁱ	86.35 (4)	C4—C3—H3	117.9 (11)
O1—Cd1—O1ⁱⁱⁱ	180.00 (3)	C3—C4—C5	117.09 (12)
O3ⁱ—Cd1—N1ⁱⁱⁱ	91.31 (4)	C3—C4—C6	122.34 (12)
O3ⁱⁱ—Cd1—N1ⁱⁱⁱ	88.69 (4)	C5—C4—C6	120.49 (13)
O1—Cd1—N1ⁱⁱⁱ	90.42 (4)	N1—C5—C4	123.49 (13)
O1ⁱⁱⁱ—Cd1—N1ⁱⁱⁱ	89.58 (4)	N1—C5—H5	116.2 (11)
O3ⁱ—Cd1—N1	88.69 (4)	C4—C5—H5	120.3 (11)
O3ⁱⁱ—Cd1—N1	91.31 (4)	C4—C6—C7	115.77 (12)
O1—Cd1—N1	89.58 (4)	C4—C6—H6A	105.5 (12)
O1ⁱⁱⁱ—Cd1—N1	90.42 (4)	C7—C6—H6A	112.2 (13)
N1ⁱⁱⁱ—Cd1—N1	180.00 (5)	C4—C6—H6B	110.2 (10)
C1—N1—C5	118.16 (11)	C7—C6—H6B	105.7 (9)
C1—N1—Cd1	120.32 (9)	H6A—C6—H6B	107.3 (13)
C5—N1—Cd1	121.52 (9)	C8—C7—C6	117.58 (12)
Cd1—O1—HO1A	97.1 (14)	C8—C7—H7A	102.6 (13)
Cd1—O1—HO1B	118.0 (18)	C6—C7—H7A	113.1 (14)
HO1A—O1—HO1B	109 (2)	C8—C7—H7B	102.8 (12)
C8—O3—Cd1^iv	124.02 (8)	C6—C7—H7B	111.3 (12)
N1—C1—C2	122.56 (13)	H7A—C7—H7B	108.6 (17)
N1—C1—H1	115.2 (11)	O3—C8—O2	125.36 (12)
C2—C1—H1	122.3 (11)	O3—C8—C7	118.03 (12)
C1—C2—C3	118.88 (13)	O2—C8—C7	116.59 (11)

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

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O1—HO1B···O2^v	0.83 (3)	2.01 (3)	2.8361 (16)	174 (2)
O1—HO1A···O2ⁱⁱ	0.88 (2)	1.94 (2)	2.7546 (17)	155 (2)

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

Experimental details

Crystal data
Chemical formula	[Cd(C₈H₈NO₂)₂(H₂O)₂]
M_r	448.74
Crystal system, space group	Monoclinic, P2₁/n
Temperature (K)	296
a, b, c (Å)	9.6934 (4), 8.9082 (4), 10.1199 (5)
β (°)	104.309 (2)
V (Å³)	846.75 (7)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	1.33
Crystal size (mm)	0.42 × 0.38 × 0.28

Data collection
Diffractometer	Bruker SMART CCD diffractometer
Absorption correction	Multi-scan (SADABS; Sheldrick, 1996)
T_min, T_max	0.606, 0.708
No. of measured, independent and observed [I > 2σ(I)] reflections	12941, 2113, 1911
R_int	0.021
(sin θ/λ)_max (Å⁻¹)	0.670

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.016, 0.042, 1.05
No. of reflections	2113
No. of parameters	155
H-atom treatment	All H-atom parameters refined
Δρ_max, Δρ_min (e Å⁻³)	0.30, −0.22

Computer programs: SMART (Bruker, 1997), SAINT (Bruker, 1997), SHELXTL (Sheldrick, 2008).

Selected geometric parameters (Å, º) top

Cd1—O3ⁱ	2.2704 (9)	Cd1—N1	2.3374 (10)
Cd1—O1	2.3306 (11)

O3ⁱ—Cd1—O1	86.35 (4)	O1—Cd1—N1	89.58 (4)
O3ⁱ—Cd1—N1ⁱⁱ	91.31 (4)

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

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O1—HO1B···O2ⁱⁱⁱ	0.83 (3)	2.01 (3)	2.8361 (16)	174 (2)
O1—HO1A···O2^iv	0.88 (2)	1.94 (2)	2.7546 (17)	155 (2)

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

Acknowledgements

This work was supported by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education, Science and Technology (No. 2009–007996).

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