catena-Poly[[dipyridine-cadmium(II)]-μ-5-amino-2,4,6-triiodo-isophthalato].

The hydro-thermal reaction of cadmium(II) nitrate with 5-amino-2,4,6-triiodo-isophthalic acid and pyridine in DMF solution leads to the formation of the title compound, [Cd(C(8)H(2)I(3)NO(4))(C(5)H(5)N)(2)](n). The structure contains a four-coordinate Cd(2+ )ion in a distorted tetra-hedral geometry, which lies on a crystallographic twofold rotation axis. The Cd(2+ )ion is bonded to two N atoms from two pyridine ligands and two carboxyl-ate O atoms from two 5-amino-2,4,6-triiodo-isophthalate anions. The Cd-O distances are 2.429 (5) and 2.305 (5) Å and the Cd-N distance is 2.236 (8) Å. The two carboxyl-ate groups of individual 5-amino-2,4,6-triiodo-isophthalate anions act as a bridge to the Cd(2+) atoms. leading to a chain structure along the c axis.

Related literature

For the isotypic Hg complex, see: Zhang et al. (2008 ▶). For the structure of 5-amino-2,4,6-triiodo­isophthalic acid monohydrate, see: Beck & Sheldrick (2008 ▶). For the structures of related metal complexes, see: n class="Gene">Dai et al. (2008 ▶)·For the use of triiodinated aromatic compounds in radiology, see: Estep et al. (2000 ▶).

Experimental

Crystal data

[Cd(C8H2I3NO4)(C5H5N)2]

M = 827.41

Tetragoical">nal,

a = 11.824 (3) Å

c = 15.841 (9) Å

V = 2214.7 (15) Å3

Z = 4

Mo Kα radiation

μ = 5.20 mm−1

T = 293 K

0.25 × 0.25 × 0.20 mm

Data collection

Bruker SMART CCD diffractometer

Absorption correction: multi-scan (SADABS; Bruker 2003 ▶) T min = 0.357, T max = 0.423

14248 measured reflections

2714 independent reflections

1949 reflections with I > 2σ(I)

R int = 0.054

Refinement

R[F 2 > 2σ(F 2)] = 0.038

wR(F 2) = 0.089

S = 1.02

2714 reflections

134 parameters

60 restraints

H-atom parameters constrained

Δρmax = 0.60 e Å−3

Δρmin = −0.87 e Å−3

Absolute structure: Flack (1983 ▶), 1096 Friedel pairs

Flack parameter: −0.04 (6)

Data collection: SMART (Bruker, 2003 ▶); cell refinement: SAINT (Bruker, 2003 ▶); data reductioical">n: SAIn class="Chemical">NT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: XP in SHELXTL (Sheldrick, 2008 ▶) and DIAMOND (Brandenburg, 2000 ▶); software used to prepare material for publication: SHELXTL and PLATON (Spek, 2009 ▶).

Crystal structure: contains datablocks I, New_Global_Publ_Block. DOI: 10.1107/S1600536810039498/si2296sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536810039498/si2296Isup2.hkl

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

[Cd(C8H2I3NO4)(C5H5N)2]	Dx = 2.482 Mg m−3
Mr = 827.41	Mo Kα radiation, λ = 0.71073 Å
Tetragonal, P41212	Cell parameters from 1949 reflections
Hall symbol: P 4abw 2nw	θ = 2.2–28.2°
a = 11.824 (3) Å	µ = 5.20 mm−1
c = 15.841 (9) Å	T = 293 K
V = 2214.7 (15) Å3	Block, light yellow
Z = 4	0.25 × 0.25 × 0.20 mm
F(000) = 1520

Bruker SMART CCD diffractometer	2714 independent reflections
Radiation source: fine-focus sealed tube	1949 reflections with I > 2σ(I)
graphite	Rint = 0.054
Detector resolution: none pixels mm-1	θmax = 28.2°, θmin = 2.2°
phi and ω scans	h = −15→15
Absorption correction: multi-scan (SADABS; Bruker 2003)	k = −14→15
Tmin = 0.357, Tmax = 0.423	l = −17→21
14248 measured reflections

Refinement on F2	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.038	H-atom parameters constrained
wR(F2) = 0.089	w = 1/[σ2(Fo2) + (0.0338P)2 + 2.974P] where P = (Fo2 + 2Fc2)/3
S = 1.02	(Δ/σ)max < 0.001
2714 reflections	Δρmax = 0.60 e Å−3
134 parameters	Δρmin = −0.87 e Å−3
60 restraints	Absolute structure: Flack (1983), 1096 Friedel pairs
Primary atom site location: structure-invariant direct methods	Flack parameter: −0.04 (6)

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.

	x	y	z	Uiso*/Ueq	Occ. (<1)
Cd1	0.62771 (5)	0.37229 (5)	0.2500	0.0572 (2)
I1	0.51631 (4)	0.51631 (4)	0.0000	0.0630 (2)
I2	0.28105 (5)	0.12921 (6)	0.17206 (4)	0.0802 (2)
N1	0.1416 (5)	0.1416 (5)	0.0000	0.064 (2)
H1A	0.1357	0.0961	0.0421	0.077*	0.50
H1B	0.0961	0.1357	−0.0421	0.077*	0.50
N2	0.6179 (7)	0.2214 (7)	0.3348 (5)	0.0771 (19)
O1	0.5507 (5)	0.2646 (5)	0.1328 (3)	0.0668 (15)
O2	0.6079 (5)	0.5525 (4)	0.3035 (3)	0.0684 (16)
C1	0.2221 (6)	0.2221 (6)	0.0000	0.051 (2)
C2	0.2982 (6)	0.2357 (6)	0.0666 (4)	0.0462 (16)
C3	0.3809 (6)	0.3171 (6)	0.0673 (4)	0.0479 (17)
C4	0.3908 (5)	0.3908 (5)	0.0000	0.043 (2)
C5	0.4652 (7)	0.3247 (7)	0.1375 (5)	0.0540 (19)
C6	0.5209 (10)	0.1691 (10)	0.3519 (9)	0.113 (3)
H6	0.4560	0.1946	0.3248	0.135*
C7	0.5108 (12)	0.0835 (12)	0.4049 (10)	0.134 (4)
H7	0.4419	0.0464	0.4114	0.161*
C8	0.6063 (12)	0.0494 (13)	0.4514 (11)	0.147 (4)
H8	0.6026	−0.0039	0.4944	0.177*
C9	0.7027 (12)	0.0999 (13)	0.4288 (10)	0.143 (4)
H9	0.7701	0.0745	0.4523	0.172*
C10	0.7060 (10)	0.1827 (10)	0.3754 (8)	0.113 (4)
H10	0.7755	0.2169	0.3654	0.135*

	U11	U22	U33	U12	U13	U23
Cd1	0.0617 (3)	0.0617 (3)	0.0482 (4)	−0.0120 (4)	−0.0049 (3)	−0.0049 (3)
I1	0.0559 (3)	0.0559 (3)	0.0773 (5)	−0.0148 (3)	0.0062 (3)	−0.0062 (3)
I2	0.0755 (4)	0.0957 (5)	0.0695 (3)	−0.0276 (4)	−0.0027 (3)	0.0291 (3)
N1	0.060 (4)	0.060 (4)	0.071 (5)	−0.027 (5)	−0.007 (4)	0.007 (4)
N2	0.075 (5)	0.073 (5)	0.083 (5)	−0.004 (4)	−0.013 (4)	−0.005 (4)
O1	0.054 (3)	0.091 (4)	0.056 (3)	0.008 (3)	−0.006 (3)	−0.012 (3)
O2	0.091 (4)	0.056 (3)	0.058 (3)	−0.003 (3)	−0.026 (3)	−0.005 (2)
C1	0.047 (3)	0.047 (3)	0.058 (5)	−0.009 (5)	0.003 (4)	−0.003 (4)
C2	0.041 (4)	0.050 (4)	0.048 (4)	−0.001 (3)	0.005 (3)	0.001 (3)
C3	0.040 (4)	0.052 (4)	0.052 (4)	−0.006 (3)	0.009 (3)	−0.005 (3)
C4	0.036 (3)	0.036 (3)	0.058 (5)	0.000 (4)	0.013 (3)	−0.013 (3)
C5	0.048 (5)	0.061 (5)	0.053 (4)	−0.011 (4)	0.006 (4)	−0.003 (4)
C6	0.077 (6)	0.105 (7)	0.156 (9)	−0.028 (6)	−0.026 (6)	0.040 (6)
C7	0.102 (7)	0.127 (8)	0.173 (9)	−0.027 (7)	−0.027 (7)	0.054 (7)
C8	0.105 (8)	0.142 (8)	0.196 (9)	−0.010 (7)	−0.031 (8)	0.062 (8)
C9	0.108 (8)	0.129 (8)	0.192 (9)	−0.026 (7)	−0.043 (8)	0.046 (8)
C10	0.075 (6)	0.102 (7)	0.161 (9)	−0.008 (6)	−0.038 (6)	0.048 (6)

Cd1—N2	2.236 (8)	C1—C2	1.395 (9)
Cd1—N2i	2.236 (8)	C1—C2ii	1.395 (9)
Cd1—O2i	2.305 (5)	C2—C3	1.373 (9)
Cd1—O2	2.305 (5)	C3—C4	1.382 (8)
Cd1—O1i	2.429 (5)	C3—C5	1.495 (11)
Cd1—O1	2.429 (5)	C4—C3ii	1.382 (8)
Cd1—C5i	2.681 (8)	C5—O2i	1.246 (9)
Cd1—C5	2.681 (8)	C6—C7	1.321 (16)
I1—C4	2.098 (8)	C6—H6	0.9300
I2—C2	2.102 (7)	C7—C8	1.407 (17)
N1—C1	1.346 (12)	C7—H7	0.9300
N1—H1A	0.8600	C8—C9	1.336 (17)
N1—H1B	0.8600	C8—H8	0.9300
N2—C10	1.307 (12)	C9—C10	1.293 (16)
N2—C6	1.331 (13)	C9—H9	0.9300
O1—C5	1.239 (10)	C10—H10	0.9300
O2—C5i	1.246 (9)
N2—Cd1—N2i	116.3 (4)	C5i—O2—Cd1	93.2 (5)
N2—Cd1—O2i	104.7 (3)	N1—C1—C2	122.5 (4)
N2i—Cd1—O2i	120.8 (2)	N1—C1—C2ii	122.5 (4)
N2—Cd1—O2	120.8 (2)	C2—C1—C2ii	115.0 (9)
N2i—Cd1—O2	104.7 (3)	C3—C2—C1	123.1 (7)
O2i—Cd1—O2	87.0 (3)	C3—C2—I2	118.8 (5)
N2—Cd1—O1i	82.4 (2)	C1—C2—I2	118.0 (5)
N2i—Cd1—O1i	91.2 (2)	C2—C3—C4	119.8 (7)
O2i—Cd1—O1i	136.7 (2)	C2—C3—C5	121.6 (7)
O2—Cd1—O1i	54.96 (18)	C4—C3—C5	118.6 (6)
N2—Cd1—O1	91.2 (2)	C3ii—C4—C3	119.2 (8)
N2i—Cd1—O1	82.4 (2)	C3ii—C4—I1	120.4 (4)
O2i—Cd1—O1	54.96 (18)	C3—C4—I1	120.4 (4)
O2—Cd1—O1	136.7 (2)	O1—C5—O2i	123.3 (7)
O1i—Cd1—O1	167.9 (3)	O1—C5—C3	117.7 (7)
N2—Cd1—C5i	100.6 (3)	O2i—C5—C3	119.0 (7)
N2i—Cd1—C5i	101.2 (3)	O1—C5—Cd1	64.8 (4)
O2i—Cd1—C5i	111.4 (2)	O2i—C5—Cd1	59.1 (4)
O2—Cd1—C5i	27.7 (2)	C3—C5—Cd1	169.9 (5)
O1i—Cd1—C5i	27.5 (2)	C7—C6—N2	124.3 (13)
O1—Cd1—C5i	164.3 (3)	C7—C6—H6	117.8
N2—Cd1—C5	101.2 (3)	N2—C6—H6	117.8
N2i—Cd1—C5	100.6 (3)	C6—C7—C8	118.7 (14)
O2i—Cd1—C5	27.7 (2)	C6—C7—H7	120.7
O2—Cd1—C5	111.4 (2)	C8—C7—H7	120.7
O1i—Cd1—C5	164.3 (3)	C9—C8—C7	114.6 (15)
O1—Cd1—C5	27.5 (2)	C9—C8—H8	122.7
C5i—Cd1—C5	138.0 (4)	C7—C8—H8	122.7
C1—N1—H1A	120.0	C10—C9—C8	122.6 (15)
C1—N1—H1B	120.0	C10—C9—H9	118.7
H1A—N1—H1B	120.0	C8—C9—H9	118.7
C10—N2—C6	115.1 (9)	C9—C10—N2	124.2 (12)
C10—N2—Cd1	122.3 (7)	C9—C10—H10	117.9
C6—N2—Cd1	122.5 (7)	N2—C10—H10	117.9
C5—O1—Cd1	87.7 (5)