Poly[[bis­[3-(1H-tetra­zol-1-yl)propanoic acid-κN4]cadmium]-di-μ-thio­cyanato-κ2N:S;κ2S:N]

Wang, J.-G.; Zhang, Y.; Su, Z.-X.; Liu, X.

doi:10.1107/S1600536812014730

metal-organic compounds

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ISSN: 2056-9890

Volume 68| Part 5| May 2012| Pages m593-m594

doi:10.1107/S1600536812014730

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Poly[[bis[3-(1H-tetrazol-1-yl)propanoic acid-κN⁴]cadmium]-di-μ-thiocyanato-κ²N:S;κ²S:N]

Jian-Guo Wang,^a Yuan Zhang,^b Zhong-Xing Su ^a and Xiang Liu ^a ^*

^aState Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou 730000, People's Republic of China, and ^bCollege of Chemistry and Chemical Engineering, Inner Mongolia University, Hohot 047100, People's Republic of China
^*Correspondence e-mail: liuxiang@lzu.edu.cn

(Received 23 March 2012; accepted 4 April 2012; online 13 April 2012)

In the title compound, [Cd(NCS)₂(C₄H₆N₄O₂)₂]_n, the Cd^II cation is located on an inversion center and is coordinated by two N and two S atoms from four SCN⁻ anions and two N atoms from two 3-(1H-tetrazol-1-yl)propanoic acid (Htzp) ligands in a distorted octahedral geometry. The SCN⁻ anions bridge the Cd^II cations into a layer structure parallel to (100). A weak intramolecular C—H⋯N interaction occurs. The layers are further assembled into a three-dimensional supramolecular structure via classical O—H⋯O hydrogen bonds.

Related literature

For general background to carboxylate-tetrazole complexes, see: Yang et al. (2009 ); He et al. (2005 ); Yu et al. (2008 ); Dong et al. (2008 ); Zhang et al. (2009 ); Li et al. (2008 , 2010 ); Xie et al. (2010 ); Bai et al. (2008 ); Voitekhovich et al. (2010 ).

Experimental

Crystal data

[Cd(NCS)₂(C₄H₆N₄O₂)₂]
M_r = 512.81
Monoclinic, P 2₁ /c
a = 12.7402 (19) Å
b = 6.9555 (11) Å
c = 10.7549 (16) Å
β = 106.809 (1)°
V = 912.3 (2) Å³
Z = 2
Mo Kα radiation
μ = 1.47 mm⁻¹
T = 296 K
0.23 × 0.22 × 0.20 mm

Data collection

Bruker APEXII CCD diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2001 ) T_min = 0.729, T_max = 0.758
5775 measured reflections
1695 independent reflections
1505 reflections with I > 2σ(I)
R_int = 0.021

Refinement

R[F² > 2σ(F²)] = 0.021
wR(F²) = 0.052
S = 1.07
1695 reflections
128 parameters
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.59 e Å⁻³
Δρ_min = −0.51 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O2—H1O⋯O1ⁱ	0.94 (4)	1.70 (4)	2.631 (3)	170 (4)
C1—H1⋯N5ⁱⁱ	0.93	2.62	3.404 (3)	142
Symmetry codes: (i) -x, -y+2, -z; (ii) -x+1, -y, -z+1.

Data collection: APEX2 (Bruker, 2007 ); cell refinement: SAINT (Bruker, 2007); 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 I, global. DOI: 10.1107/S1600536812014730/xu5497sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536812014730/xu5497Isup2.hkl

checkCIF report

Comment top

Recently, the design and synthesis of carboxylate-tetrazole coordination compounds have been of an attractive area of research due to their intriguing topological structures as well as their novel physical properties such as anion exchange, photoluminescence, magnetism behavior and biological activities etc. (Yang et al., 2009; Yu et al., 2008; Li et al., 2010; He et al., 2005; Li et al., 2008; Dong et al., 2008; Xie et al., 2010; Bai et al., 2008; Voitekhovich et al., 2010). Herein, we report the structure of the title coordination polymer based on a flexible ligand tetrazole-1-propanoic acid (Htzp).

The title coordination polymer crystallizes in the monoclinic space group P2₁/c and the asymmetric unit contains half of the [Cd(Htzp)₂(SCN)₂] molecule (Fig. 1). Each Cd²⁺ ion lies on the inversion center of an octahedral environment and is coordinated by two N atoms from two Htzp, two N and two O atoms from four different SCN^- ions. Each Cd²⁺ center is linked to four adjacent Cd²⁺centers by four SCN^- ions, resulting in a two-dimensional layer structure with Cd···Cd distance of 6.404 Å (Fig. 2). The adjacent two-dimensional layers are further linked through intermolecular hydrogen-bonding interaction between two not coordinated carboxylate group (O2—H1···O1 = 2.631 Å) to afford a three-dimensional supramolecular structure (Fig. 3). In addition, weak intramolecular hydrogen bonds (C1—H1···N5 = 3.404 Å) are present in the crystal structure.

Related literature top

For general background to carboxylate-tetrazole complexes, see: Yang et al. (2009); He et al. (2005); Yu et al. (2008); Dong et al. (2008); Zhang et al. (2009); Li et al. (2008, 2010); Xie et al. (2010); Bai et al. (2008); Voitekhovich et al. (2010).

Experimental top

The Htzp (0.0284 g, 0.2 mmol) and NH₄SCN (0.0152 g, 0.2 mmol) were mixed in distilled water (5 ml) and ethanol (3 ml). Then, CdCl₂ (0.0367 g, 0.2 mmol) dissolved in distilled water (5 ml) was added slowly to the mixture. The mixture was allowed to slowly concentrate by evaporation at room temperature. Several days later, colorless block crystals suitable for X-ray diffraction were obtained with yield 63% on the basis of Htzp.

Computing details top

Data collection: APEX2 (Bruker, 2007); cell refinement: SAINT (Bruker, 2007); data reduction: SAINT (Bruker, 2007); 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. coordination environments of cadmium atoms in the title coordination polymer. Displacement ellipsoids are drawn at the 30% probability level. H atoms have been omitted for clarity.
	Fig. 2. The two-dimensional layer structure of the title coordination polymer along the bc plane. H atoms have been omitted for clarity.
	Fig. 3. The three-dimensional supramolecular structure of the title coordination polymer. Hydrogen bonds are shown as dashed lines.

Poly[[bis[3-(1H-tetrazol-1-yl)propanoic acid-κN⁴]cadmium]- di-µ-thiocyanato-κ²N:S;κ²S:N] top

Crystal data top

[Cd(NCS)₂(C₄H₆N₄O₂)₂]	F(000) = 508
M_r = 512.81	D_x = 1.863 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 4116 reflections
a = 12.7402 (19) Å	θ = 3.3–28.3°
b = 6.9555 (11) Å	µ = 1.47 mm⁻¹
c = 10.7549 (16) Å	T = 296 K
β = 106.809 (1)°	Block, blue
V = 912.3 (2) Å³	0.23 × 0.22 × 0.20 mm
Z = 2

Data collection top

Bruker APEXII CCD diffractometer	1695 independent reflections
Radiation source: fine-focus sealed tube	1505 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.021
ϕ and ω scans	θ_max = 25.5°, θ_min = 3.3°
Absorption correction: multi-scan (SADABS; Bruker, 2001)	h = −15→15
T_min = 0.729, T_max = 0.758	k = −8→8
5775 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)] = 0.021	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.052	H atoms treated by a mixture of independent and constrained refinement
S = 1.07	w = 1/[σ²(F_o²) + (0.0245P)² + 0.480P] where P = (F_o² + 2F_c²)/3
1695 reflections	(Δ/σ)_max < 0.001
128 parameters	Δρ_max = 0.59 e Å⁻³
0 restraints	Δρ_min = −0.51 e Å⁻³

Crystal data top

[Cd(NCS)₂(C₄H₆N₄O₂)₂]	V = 912.3 (2) Å³
M_r = 512.81	Z = 2
Monoclinic, P2₁/c	Mo Kα radiation
a = 12.7402 (19) Å	µ = 1.47 mm⁻¹
b = 6.9555 (11) Å	T = 296 K
c = 10.7549 (16) Å	0.23 × 0.22 × 0.20 mm
β = 106.809 (1)°

Data collection top

Bruker APEXII CCD diffractometer	1695 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2001)	1505 reflections with I > 2σ(I)
T_min = 0.729, T_max = 0.758	R_int = 0.021
5775 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.021	0 restraints
wR(F²) = 0.052	H atoms treated by a mixture of independent and constrained refinement
S = 1.07	Δρ_max = 0.59 e Å⁻³
1695 reflections	Δρ_min = −0.51 e Å⁻³
128 parameters

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
C1	0.30765 (19)	0.2887 (4)	0.3041 (2)	0.0348 (5)
H1	0.3447	0.2929	0.2412	0.042*
C2	0.1466 (2)	0.4991 (3)	0.1939 (2)	0.0370 (6)
H2A	0.0708	0.4582	0.1737	0.044*
H2B	0.1698	0.4853	0.1160	0.044*
C3	0.1555 (2)	0.7069 (3)	0.2350 (2)	0.0342 (5)
H3A	0.1298	0.7213	0.3110	0.041*
H3B	0.2318	0.7463	0.2584	0.041*
C4	0.08935 (19)	0.8341 (3)	0.1283 (2)	0.0314 (5)
C5	0.42494 (19)	−0.3428 (4)	0.6880 (2)	0.0337 (5)
Cd1	0.5000	0.0000	0.5000	0.02720 (9)
N1	0.33986 (16)	0.1944 (3)	0.41393 (17)	0.0345 (5)
N2	0.26241 (18)	0.2267 (3)	0.4749 (2)	0.0426 (5)
N3	0.18639 (17)	0.3363 (3)	0.4049 (2)	0.0419 (5)
N4	0.21474 (15)	0.3766 (3)	0.29673 (17)	0.0289 (4)
N5	0.46640 (18)	−0.3889 (3)	0.79258 (19)	0.0447 (6)
O1	0.04537 (15)	0.7745 (3)	0.01892 (15)	0.0402 (4)
O2	0.08335 (18)	1.0111 (3)	0.16420 (19)	0.0493 (5)
S1	0.36445 (7)	−0.27644 (12)	0.53866 (6)	0.0594 (2)
H1O	0.042 (3)	1.083 (6)	0.093 (4)	0.080 (11)*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C1	0.0356 (13)	0.0419 (15)	0.0290 (11)	0.0104 (11)	0.0129 (10)	0.0079 (10)
C2	0.0396 (13)	0.0343 (14)	0.0302 (12)	0.0123 (11)	−0.0007 (10)	0.0047 (10)
C3	0.0360 (13)	0.0327 (14)	0.0299 (11)	0.0036 (11)	0.0032 (10)	0.0038 (10)
C4	0.0322 (12)	0.0298 (14)	0.0303 (11)	0.0015 (10)	0.0061 (10)	0.0033 (10)
C5	0.0348 (12)	0.0343 (14)	0.0324 (13)	−0.0070 (11)	0.0101 (10)	0.0043 (10)
Cd1	0.03311 (14)	0.02849 (15)	0.01786 (12)	0.00767 (10)	0.00396 (9)	0.00081 (9)
N1	0.0377 (11)	0.0369 (12)	0.0300 (9)	0.0113 (9)	0.0113 (8)	0.0079 (9)
N2	0.0506 (13)	0.0425 (13)	0.0407 (11)	0.0153 (11)	0.0227 (10)	0.0164 (10)
N3	0.0435 (12)	0.0452 (14)	0.0424 (12)	0.0132 (10)	0.0209 (10)	0.0129 (10)
N4	0.0304 (10)	0.0281 (11)	0.0271 (9)	0.0063 (8)	0.0064 (8)	0.0041 (8)
N5	0.0533 (13)	0.0522 (15)	0.0279 (11)	−0.0044 (11)	0.0105 (10)	0.0109 (10)
O1	0.0462 (10)	0.0340 (10)	0.0322 (8)	0.0089 (8)	−0.0018 (7)	0.0016 (7)
O2	0.0655 (13)	0.0303 (11)	0.0379 (10)	0.0106 (9)	−0.0076 (9)	−0.0006 (8)
S1	0.0620 (5)	0.0644 (5)	0.0352 (3)	−0.0248 (4)	−0.0121 (3)	0.0207 (3)

Geometric parameters (Å, º) top

C1—N1	1.310 (3)	C5—S1	1.634 (2)
C1—N4	1.314 (3)	Cd1—N5ⁱ	2.281 (2)
C1—H1	0.9300	Cd1—N5ⁱⁱ	2.281 (2)
C2—N4	1.466 (3)	Cd1—N1ⁱⁱⁱ	2.3989 (19)
C2—C3	1.506 (3)	Cd1—N1	2.3990 (19)
C2—H2A	0.9700	Cd1—S1ⁱⁱⁱ	2.6958 (8)
C2—H2B	0.9700	Cd1—S1	2.6958 (8)
C3—C4	1.500 (3)	N1—N2	1.352 (3)
C3—H3A	0.9700	N2—N3	1.290 (3)
C3—H3B	0.9700	N3—N4	1.343 (3)
C4—O1	1.220 (3)	N5—Cd1^iv	2.281 (2)
C4—O2	1.299 (3)	O2—H1O	0.94 (4)
C5—N5	1.142 (3)

N1—C1—N4	109.2 (2)	N5ⁱⁱ—Cd1—N1	94.85 (7)
N1—C1—H1	125.4	N1ⁱⁱⁱ—Cd1—N1	180.0
N4—C1—H1	125.4	N5ⁱ—Cd1—S1ⁱⁱⁱ	92.19 (6)
N4—C2—C3	111.01 (19)	N5ⁱⁱ—Cd1—S1ⁱⁱⁱ	87.81 (6)
N4—C2—H2A	109.4	N1ⁱⁱⁱ—Cd1—S1ⁱⁱⁱ	87.15 (5)
C3—C2—H2A	109.4	N1—Cd1—S1ⁱⁱⁱ	92.85 (5)
N4—C2—H2B	109.4	N5ⁱ—Cd1—S1	87.81 (6)
C3—C2—H2B	109.4	N5ⁱⁱ—Cd1—S1	92.19 (6)
H2A—C2—H2B	108.0	N1ⁱⁱⁱ—Cd1—S1	92.85 (5)
C4—C3—C2	111.32 (19)	N1—Cd1—S1	87.15 (5)
C4—C3—H3A	109.4	S1ⁱⁱⁱ—Cd1—S1	180.0
C2—C3—H3A	109.4	C1—N1—N2	105.79 (19)
C4—C3—H3B	109.4	C1—N1—Cd1	129.80 (16)
C2—C3—H3B	109.4	N2—N1—Cd1	124.41 (14)
H3A—C3—H3B	108.0	N3—N2—N1	110.18 (18)
O1—C4—O2	123.9 (2)	N2—N3—N4	106.52 (18)
O1—C4—C3	122.5 (2)	C1—N4—N3	108.31 (18)
O2—C4—C3	113.6 (2)	C1—N4—C2	130.0 (2)
N5—C5—S1	179.4 (2)	N3—N4—C2	121.74 (19)
N5ⁱ—Cd1—N5ⁱⁱ	180.0	C5—N5—Cd1^iv	164.0 (2)
N5ⁱ—Cd1—N1ⁱⁱⁱ	94.85 (7)	C4—O2—H1O	109 (2)
N5ⁱⁱ—Cd1—N1ⁱⁱⁱ	85.15 (7)	C5—S1—Cd1	102.24 (9)
N5ⁱ—Cd1—N1	85.15 (7)

N4—C2—C3—C4	177.9 (2)	Cd1—N1—N2—N3	−179.93 (16)
C2—C3—C4—O1	−7.7 (3)	N1—N2—N3—N4	−0.2 (3)
C2—C3—C4—O2	171.9 (2)	N1—C1—N4—N3	−0.4 (3)
N4—C1—N1—N2	0.2 (3)	N1—C1—N4—C2	180.0 (2)
N4—C1—N1—Cd1	−179.88 (15)	N2—N3—N4—C1	0.3 (3)
N5ⁱ—Cd1—N1—C1	−40.8 (2)	N2—N3—N4—C2	−180.0 (2)
N5ⁱⁱ—Cd1—N1—C1	139.2 (2)	C3—C2—N4—C1	−106.9 (3)
N1ⁱⁱⁱ—Cd1—N1—C1	−19 (32)	C3—C2—N4—N3	73.4 (3)
S1ⁱⁱⁱ—Cd1—N1—C1	51.2 (2)	S1—C5—N5—Cd1^iv	23 (27)
S1—Cd1—N1—C1	−128.8 (2)	N5—C5—S1—Cd1	128 (26)
N5ⁱ—Cd1—N1—N2	139.1 (2)	N5ⁱ—Cd1—S1—C5	142.55 (11)
N5ⁱⁱ—Cd1—N1—N2	−40.9 (2)	N5ⁱⁱ—Cd1—S1—C5	−37.45 (11)
N1ⁱⁱⁱ—Cd1—N1—N2	161 (32)	N1ⁱⁱⁱ—Cd1—S1—C5	47.80 (11)
S1ⁱⁱⁱ—Cd1—N1—N2	−128.94 (19)	N1—Cd1—S1—C5	−132.20 (11)
S1—Cd1—N1—N2	51.05 (19)	S1ⁱⁱⁱ—Cd1—S1—C5	−57 (10)
C1—N1—N2—N3	0.0 (3)

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

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O2—H1O···O1^v	0.94 (4)	1.70 (4)	2.631 (3)	170 (4)
C1—H1···N5ⁱⁱⁱ	0.93	2.62	3.404 (3)	142

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

Experimental details

Crystal data
Chemical formula	[Cd(NCS)₂(C₄H₆N₄O₂)₂]
M_r	512.81
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	296
a, b, c (Å)	12.7402 (19), 6.9555 (11), 10.7549 (16)
β (°)	106.809 (1)
V (Å³)	912.3 (2)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	1.47
Crystal size (mm)	0.23 × 0.22 × 0.20

Data collection
Diffractometer	Bruker APEXII CCD diffractometer
Absorption correction	Multi-scan (SADABS; Bruker, 2001)
T_min, T_max	0.729, 0.758
No. of measured, independent and observed [I > 2σ(I)] reflections	5775, 1695, 1505
R_int	0.021
(sin θ/λ)_max (Å⁻¹)	0.606

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.021, 0.052, 1.07
No. of reflections	1695
No. of parameters	128
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.59, −0.51

Computer programs: APEX2 (Bruker, 2007), SAINT (Bruker, 2007), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O2—H1O···O1ⁱ	0.94 (4)	1.70 (4)	2.631 (3)	170 (4)
C1—H1···N5ⁱⁱ	0.93	2.62	3.404 (3)	142

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

Acknowledgements

This work was supported by the Fundamental Research Funds for the Central Universities of China (grant 2010–43).

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