Supporting information
Crystallographic Information File (CIF) https://doi.org/10.1107/S1600536810039498/si2296sup1.cif | |
Structure factor file (CIF format) https://doi.org/10.1107/S1600536810039498/si2296Isup2.hkl |
CCDC reference: 799426
Key indicators
- Single-crystal X-ray study
- T = 293 K
- Mean (C-C) = 0.014 Å
- R factor = 0.038
- wR factor = 0.089
- Data-to-parameter ratio = 20.3
checkCIF/PLATON results
No syntax errors found
Alert level C PLAT220_ALERT_2_C Large Non-Solvent C Ueq(max)/Ueq(min) ... 3.44 Ratio PLAT242_ALERT_2_C Check Low Ueq as Compared to Neighbors for N2 PLAT342_ALERT_3_C Low Bond Precision on C-C Bonds (x 1000) Ang .. 14 PLAT234_ALERT_4_C Large Hirshfeld Difference C9 -- C10 .. 0.17 Ang. PLAT912_ALERT_4_C Missing # of FCF Reflections Above STh/L= 0.600 2
Alert level G REFLT03_ALERT_4_G Please check that the estimate of the number of Friedel pairs is correct. If it is not, please give the correct count in the _publ_section_exptl_refinement section of the submitted CIF. From the CIF: _diffrn_reflns_theta_max 28.16 From the CIF: _reflns_number_total 2714 Count of symmetry unique reflns 1618 Completeness (_total/calc) 167.74% TEST3: Check Friedels for noncentro structure Estimate of Friedel pairs measured 1096 Fraction of Friedel pairs measured 0.677 Are heavy atom types Z>Si present yes PLAT860_ALERT_3_G Note: Number of Least-Squares Restraints ....... 60 PLAT199_ALERT_1_G Check the Reported _cell_measurement_temperature 293 K PLAT200_ALERT_1_G Check the Reported _diffrn_ambient_temperature 293 K PLAT764_ALERT_4_G Overcomplete CIF Bond List Detected (Rep/Expd) . 1.18 Ratio
0 ALERT level A = In general: serious problem 0 ALERT level B = Potentially serious problem 5 ALERT level C = Check and explain 5 ALERT level G = General alerts; check 2 ALERT type 1 CIF construction/syntax error, inconsistent or missing data 2 ALERT type 2 Indicator that the structure model may be wrong or deficient 2 ALERT type 3 Indicator that the structure quality may be low 4 ALERT type 4 Improvement, methodology, query or suggestion 0 ALERT type 5 Informative message, check
5-amino-2,4,6-triiodoisophthalic acid (0.5 mmol) was dissolved in 10 ml DMA, in which Cd(NO3)2(0.5 mmol) and 20 µl pyridine were added in. The mixture was sealed in a Pyrex tube and heated at 358 K for 3 d. After cooling to room temperature, light yellow block crystals were obtained.
All H atoms were positioned geometrically and constrained as riding atoms, with C—H distance of 0.93 Å and Uiso(H) set to 1.2 Ueq(C) of the parent atom.
5-Amino-2,4,6-triiodoisophthalic acid (ATIA), is the precursor and core structure of triiodinated contrast media used in radiology (Estep et al., 2000). The crystal structure of this compound was reported recently (Beck et al., 2008), however, there are very few studies that have been reported on the structural characterization of its metal complexes (Dai et al., 2008; Zhang et al., 2008). Here we report the synthesis and crystal structure of the title complex catena-[bis(pyridine)-µ-5-amino-2,4,6-triiodoisophthalic acid-O,O-cadmium(II)].
In the title complex the central cadmium ion is coordinated by two nitrogen atoms from two pyridine ligands and two oxygen atoms from different ATIA ligands in a tetrahedral geometry. The bond lengths are 2.236 (8)Å for Cd1—N2; 2.305 (5) Å for Cd1—O2 and 2.429 (5) Å for Cd1—O1. Both carboxylate groups of ATIA ligand are deprotonated during the reaction, and the whole ligand acts as a bridging linker to connect two cadmium ions. Thus, the [Cd(pyr)2] units are infinitely connected by ATIA ligands along the c axis to give rise to a one-dimensional chain structure.
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 Dai et al. (2008).For the use of triiodinated aromatic compounds in radiology, see: Estep et al. (2000).
Data collection: SMART (Bruker, 2003); cell refinement: SAINT (Bruker, 2003); data reduction: SAINT (Bruker, 2003); 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 (Sheldrick, 2008) and PLATON (Spek, 2009).
Fig. 1. ORTEP plot of the title complex with atom numbering scheme. Thermal ellipsoids are drawn at 40% probability level. | |
Fig. 2. A section of the infinite [Cd(ATIA)(pyr)2]n chain along the c axis. |
[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 monochromator | 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 | Absolute structure parameter: −0.04 (6) |
[Cd(C8H2I3NO4)(C5H5N)2] | Z = 4 |
Mr = 827.41 | Mo Kα radiation |
Tetragonal, P41212 | µ = 5.20 mm−1 |
a = 11.824 (3) Å | T = 293 K |
c = 15.841 (9) Å | 0.25 × 0.25 × 0.20 mm |
V = 2214.7 (15) Å3 |
Bruker SMART CCD diffractometer | 2714 independent reflections |
Absorption correction: multi-scan (SADABS; Bruker 2003) | 1949 reflections with I > 2σ(I) |
Tmin = 0.357, Tmax = 0.423 | Rint = 0.054 |
14248 measured reflections |
R[F2 > 2σ(F2)] = 0.038 | H-atom parameters constrained |
wR(F2) = 0.089 | Δρmax = 0.60 e Å−3 |
S = 1.02 | Δρmin = −0.87 e Å−3 |
2714 reflections | Absolute structure: Flack (1983), 1096 Friedel pairs |
134 parameters | Absolute structure parameter: −0.04 (6) |
60 restraints |
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) |
Symmetry codes: (i) −y+1, −x+1, −z+1/2; (ii) y, x, −z. |
Experimental details
Crystal data | |
Chemical formula | [Cd(C8H2I3NO4)(C5H5N)2] |
Mr | 827.41 |
Crystal system, space group | Tetragonal, P41212 |
Temperature (K) | 293 |
a, c (Å) | 11.824 (3), 15.841 (9) |
V (Å3) | 2214.7 (15) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 5.20 |
Crystal size (mm) | 0.25 × 0.25 × 0.20 |
Data collection | |
Diffractometer | Bruker SMART CCD |
Absorption correction | Multi-scan (SADABS; Bruker 2003) |
Tmin, Tmax | 0.357, 0.423 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 14248, 2714, 1949 |
Rint | 0.054 |
(sin θ/λ)max (Å−1) | 0.664 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.038, 0.089, 1.02 |
No. of reflections | 2714 |
No. of parameters | 134 |
No. of restraints | 60 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.60, −0.87 |
Absolute structure | Flack (1983), 1096 Friedel pairs |
Absolute structure parameter | −0.04 (6) |
Computer programs: SMART (Bruker, 2003), SAINT (Bruker, 2003), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), XP in SHELXTL (Sheldrick, 2008) and DIAMOND (Brandenburg, 2000), SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).
5-Amino-2,4,6-triiodoisophthalic acid (ATIA), is the precursor and core structure of triiodinated contrast media used in radiology (Estep et al., 2000). The crystal structure of this compound was reported recently (Beck et al., 2008), however, there are very few studies that have been reported on the structural characterization of its metal complexes (Dai et al., 2008; Zhang et al., 2008). Here we report the synthesis and crystal structure of the title complex catena-[bis(pyridine)-µ-5-amino-2,4,6-triiodoisophthalic acid-O,O-cadmium(II)].
In the title complex the central cadmium ion is coordinated by two nitrogen atoms from two pyridine ligands and two oxygen atoms from different ATIA ligands in a tetrahedral geometry. The bond lengths are 2.236 (8)Å for Cd1—N2; 2.305 (5) Å for Cd1—O2 and 2.429 (5) Å for Cd1—O1. Both carboxylate groups of ATIA ligand are deprotonated during the reaction, and the whole ligand acts as a bridging linker to connect two cadmium ions. Thus, the [Cd(pyr)2] units are infinitely connected by ATIA ligands along the c axis to give rise to a one-dimensional chain structure.