Supporting information
Crystallographic Information File (CIF) https://doi.org/10.1107/S1600536807062447/ci2521sup1.cif | |
Structure factor file (CIF format) https://doi.org/10.1107/S1600536807062447/ci2521Isup2.hkl |
CCDC reference: 672771
The ligand picolinic acid hydrazide was prepared as described previously (Klingele & Brooker, 2004), by refluxing the respective picolinic acid ethylester for 4 h with a slight excess of hydrazine monohydrate. The product was recrystallized from ethanol. The cadmium complex was synthesized by adding a solution of CdCl2·2.5H2O (0.229 g, 1 mmol) in methanol (20 ml) to a stirred solution of picolinic acid hydrazide (0.274 g, 2 mmol) in methanol (20 ml). The mixture was stirred for 1 h at room temperature. Colourless crystals were obatined after leaving the solution to evaporate for 3 d. The crystals were collected by filtration, washed with cold methanol and dried in a desiccator.
All H atoms were initially located in a difference Fourier map and later placed in idealized positions and constrained to ride on their parent atoms, with C—H = 0.93 Å, N—H = 0.86 or 0.90 Å and Uiso(H) = 1.2eq(C).
Data collection: SMART (Bruker, 1997); cell refinement: SAINT (Bruker, 1997); data reduction: SAINT (Bruker, 1997); program(s) used to solve structure: SHELXS97 (Sheldrick, 1990); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: PLATON (Spek, 2003); software used to prepare material for publication: PLATON (Spek, 2003).
[CdCl2(C6H7N3O)2] | F(000) = 904 |
Mr = 457.60 | Dx = 1.872 Mg m−3 |
Monoclinic, C2/c | Cu Kα radiation, λ = 1.54178 Å |
Hall symbol: -C 2yc | Cell parameters from 2348 reflections |
a = 16.9951 (7) Å | θ = 5.3–71.6° |
b = 6.7365 (2) Å | µ = 13.97 mm−1 |
c = 14.3313 (6) Å | T = 293 K |
β = 98.221 (3)° | Rod, colourless |
V = 1623.89 (11) Å3 | 0.30 × 0.15 × 0.10 mm |
Z = 4 |
Bruker SMART 6000 diffractometer | 1395 independent reflections |
Radiation source: fine-focus sealed tube | 1349 reflections with I > 2σ(I) |
Crossed Göbel mirrors monochromator | Rint = 0.036 |
ω and ϕ scans | θmax = 66.6°, θmin = 5.3° |
Absorption correction: multi-scan (SADABS; Bruker, 1997) | h = −20→17 |
Tmin = 0.116, Tmax = 0.247 | k = −8→7 |
5326 measured reflections | l = −16→17 |
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)] = 0.027 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.067 | H-atom parameters constrained |
S = 1.11 | w = 1/[σ2(Fo2) + (0.0362P)2 + 1.6198P] where P = (Fo2 + 2Fc2)/3 |
1395 reflections | (Δ/σ)max = 0.001 |
105 parameters | Δρmax = 0.52 e Å−3 |
0 restraints | Δρmin = −0.90 e Å−3 |
[CdCl2(C6H7N3O)2] | V = 1623.89 (11) Å3 |
Mr = 457.60 | Z = 4 |
Monoclinic, C2/c | Cu Kα radiation |
a = 16.9951 (7) Å | µ = 13.97 mm−1 |
b = 6.7365 (2) Å | T = 293 K |
c = 14.3313 (6) Å | 0.30 × 0.15 × 0.10 mm |
β = 98.221 (3)° |
Bruker SMART 6000 diffractometer | 1395 independent reflections |
Absorption correction: multi-scan (SADABS; Bruker, 1997) | 1349 reflections with I > 2σ(I) |
Tmin = 0.116, Tmax = 0.247 | Rint = 0.036 |
5326 measured reflections |
R[F2 > 2σ(F2)] = 0.027 | 0 restraints |
wR(F2) = 0.067 | H-atom parameters constrained |
S = 1.11 | Δρmax = 0.52 e Å−3 |
1395 reflections | Δρmin = −0.90 e Å−3 |
105 parameters |
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 | ||
C1 | 0.18958 (16) | −0.0129 (4) | 0.4884 (2) | 0.0251 (6) | |
C2 | 0.26626 (17) | 0.0003 (4) | 0.4662 (2) | 0.0285 (6) | |
H2 | 0.2758 | −0.0039 | 0.4039 | 0.034* | |
C3 | 0.32779 (17) | 0.0197 (4) | 0.5395 (2) | 0.0325 (7) | |
H3 | 0.3799 | 0.0312 | 0.5272 | 0.039* | |
C4 | 0.31165 (19) | 0.0218 (5) | 0.6308 (3) | 0.0375 (7) | |
H4 | 0.3525 | 0.0319 | 0.6812 | 0.045* | |
C5 | 0.2330 (2) | 0.0087 (5) | 0.6461 (2) | 0.0392 (8) | |
H5 | 0.2222 | 0.0111 | 0.7079 | 0.047* | |
C6 | 0.12048 (16) | −0.0340 (4) | 0.4117 (2) | 0.0227 (5) | |
N1 | 0.17201 (15) | −0.0072 (4) | 0.57595 (18) | 0.0313 (6) | |
N2 | 0.05532 (15) | −0.1154 (3) | 0.43715 (19) | 0.0253 (5) | |
H2A | 0.0547 | −0.1535 | 0.4943 | 0.030* | |
N3 | −0.01277 (14) | −0.1381 (3) | 0.36872 (18) | 0.0239 (5) | |
H3A | −0.0574 | −0.1181 | 0.3945 | 0.029* | |
H3B | −0.0144 | −0.2608 | 0.3436 | 0.029* | |
O1 | 0.12502 (12) | 0.0236 (3) | 0.33022 (15) | 0.0307 (5) | |
Cl1 | 0.03593 (5) | 0.36372 (10) | 0.13274 (6) | 0.03299 (19) | |
Cd1 | 0.0000 | 0.10888 (4) | 0.2500 | 0.02458 (13) |
U11 | U22 | U33 | U12 | U13 | U23 | |
C1 | 0.0255 (15) | 0.0245 (13) | 0.0247 (16) | 0.0018 (10) | 0.0019 (11) | 0.0020 (10) |
C2 | 0.0266 (15) | 0.0279 (13) | 0.0309 (17) | 0.0035 (10) | 0.0040 (12) | 0.0014 (11) |
C3 | 0.0203 (14) | 0.0309 (15) | 0.045 (2) | 0.0009 (11) | 0.0011 (12) | 0.0001 (13) |
C4 | 0.0320 (17) | 0.0385 (17) | 0.038 (2) | −0.0031 (13) | −0.0099 (13) | 0.0008 (13) |
C5 | 0.0374 (18) | 0.053 (2) | 0.0251 (19) | −0.0067 (14) | −0.0012 (13) | 0.0007 (14) |
C6 | 0.0240 (13) | 0.0237 (13) | 0.0202 (15) | 0.0035 (10) | 0.0029 (10) | 0.0017 (10) |
N1 | 0.0280 (13) | 0.0412 (14) | 0.0237 (15) | −0.0035 (10) | 0.0006 (10) | 0.0008 (10) |
N2 | 0.0239 (12) | 0.0305 (13) | 0.0207 (15) | −0.0016 (8) | 0.0006 (10) | 0.0032 (8) |
N3 | 0.0220 (12) | 0.0272 (11) | 0.0216 (14) | −0.0028 (9) | 0.0002 (9) | −0.0009 (9) |
O1 | 0.0239 (10) | 0.0433 (12) | 0.0245 (12) | −0.0003 (8) | 0.0018 (8) | 0.0058 (9) |
Cl1 | 0.0444 (4) | 0.0284 (3) | 0.0278 (5) | 0.0019 (3) | 0.0107 (3) | 0.0038 (3) |
Cd1 | 0.02608 (18) | 0.02668 (18) | 0.0197 (2) | 0.000 | −0.00130 (11) | 0.000 |
C1—N1 | 1.331 (4) | C6—N2 | 1.332 (4) |
C1—C2 | 1.388 (4) | N2—N3 | 1.414 (3) |
C1—C6 | 1.497 (4) | N2—H2A | 0.86 |
C2—C3 | 1.378 (4) | N3—Cd1 | 2.412 (2) |
C2—H2 | 0.93 | N3—H3A | 0.90 |
C3—C4 | 1.375 (5) | N3—H3B | 0.90 |
C3—H3 | 0.93 | O1—Cd1 | 2.338 (2) |
C4—C5 | 1.387 (5) | Cl1—Cd1 | 2.5372 (7) |
C4—H4 | 0.93 | Cd1—O1i | 2.338 (2) |
C5—N1 | 1.342 (4) | Cd1—N3i | 2.412 (2) |
C5—H5 | 0.93 | Cd1—Cl1i | 2.5371 (7) |
C6—O1 | 1.243 (4) | ||
N1—C1—C2 | 124.0 (3) | N2—N3—Cd1 | 105.50 (15) |
N1—C1—C6 | 115.9 (2) | N2—N3—H3A | 110.6 |
C2—C1—C6 | 120.1 (3) | Cd1—N3—H3A | 110.6 |
C3—C2—C1 | 117.8 (3) | N2—N3—H3B | 110.6 |
C3—C2—H2 | 121.1 | Cd1—N3—H3B | 110.6 |
C1—C2—H2 | 121.1 | H3A—N3—H3B | 108.8 |
C4—C3—C2 | 119.6 (3) | C6—O1—Cd1 | 111.37 (17) |
C4—C3—H3 | 120.2 | O1—Cd1—O1i | 151.56 (11) |
C2—C3—H3 | 120.2 | O1—Cd1—N3 | 69.56 (8) |
C3—C4—C5 | 118.5 (3) | O1i—Cd1—N3 | 90.59 (8) |
C3—C4—H4 | 120.7 | O1—Cd1—N3i | 90.59 (8) |
C5—C4—H4 | 120.7 | O1i—Cd1—N3i | 69.56 (8) |
N1—C5—C4 | 123.0 (3) | N3—Cd1—N3i | 92.74 (12) |
N1—C5—H5 | 118.5 | O1—Cd1—Cl1i | 97.38 (6) |
C4—C5—H5 | 118.5 | O1i—Cd1—Cl1i | 101.77 (5) |
O1—C6—N2 | 123.4 (3) | N3—Cd1—Cl1i | 86.86 (6) |
O1—C6—C1 | 120.9 (2) | N3i—Cd1—Cl1i | 171.32 (6) |
N2—C6—C1 | 115.7 (2) | O1—Cd1—Cl1 | 101.77 (5) |
C1—N1—C5 | 117.1 (3) | O1i—Cd1—Cl1 | 97.38 (6) |
C6—N2—N3 | 119.0 (2) | N3—Cd1—Cl1 | 171.32 (6) |
C6—N2—H2A | 120.5 | N3i—Cd1—Cl1 | 86.86 (6) |
N3—N2—H2A | 120.5 | Cl1i—Cd1—Cl1 | 94.84 (3) |
N1—C1—C2—C3 | 0.3 (4) | C1—C6—N2—N3 | 179.3 (2) |
C6—C1—C2—C3 | 179.9 (3) | C6—N2—N3—Cd1 | −24.3 (3) |
C1—C2—C3—C4 | 1.1 (4) | N2—C6—O1—Cd1 | 26.2 (3) |
C2—C3—C4—C5 | −1.4 (5) | C1—C6—O1—Cd1 | −153.2 (2) |
C3—C4—C5—N1 | 0.4 (5) | C6—O1—Cd1—O1i | −75.72 (18) |
N1—C1—C6—O1 | 155.8 (3) | C6—O1—Cd1—N3 | −27.42 (18) |
C2—C1—C6—O1 | −23.9 (4) | C6—O1—Cd1—N3i | −120.12 (19) |
N1—C1—C6—N2 | −23.6 (4) | C6—O1—Cd1—Cl1i | 56.43 (19) |
C2—C1—C6—N2 | 156.7 (3) | C6—O1—Cd1—Cl1 | 152.96 (18) |
C2—C1—N1—C5 | −1.2 (4) | N2—N3—Cd1—O1 | 25.21 (15) |
C6—C1—N1—C5 | 179.1 (3) | N2—N3—Cd1—O1i | −175.62 (16) |
C4—C5—N1—C1 | 0.9 (5) | N2—N3—Cd1—N3i | 114.82 (18) |
O1—C6—N2—N3 | −0.1 (4) | N2—N3—Cd1—Cl1i | −73.86 (16) |
Symmetry code: (i) −x, y, −z+1/2. |
D—H···A | D—H | H···A | D···A | D—H···A |
N2—H2A···Cl1ii | 0.86 | 2.49 | 3.321 (3) | 161 |
N3—H3A···N1iii | 0.90 | 2.22 | 3.086 (4) | 162 |
N3—H3B···Cl1iv | 0.90 | 2.59 | 3.379 (2) | 147 |
Symmetry codes: (ii) x, −y, z+1/2; (iii) −x, −y, −z+1; (iv) −x, y−1, −z+1/2. |
Experimental details
Crystal data | |
Chemical formula | [CdCl2(C6H7N3O)2] |
Mr | 457.60 |
Crystal system, space group | Monoclinic, C2/c |
Temperature (K) | 293 |
a, b, c (Å) | 16.9951 (7), 6.7365 (2), 14.3313 (6) |
β (°) | 98.221 (3) |
V (Å3) | 1623.89 (11) |
Z | 4 |
Radiation type | Cu Kα |
µ (mm−1) | 13.97 |
Crystal size (mm) | 0.30 × 0.15 × 0.10 |
Data collection | |
Diffractometer | Bruker SMART 6000 diffractometer |
Absorption correction | Multi-scan (SADABS; Bruker, 1997) |
Tmin, Tmax | 0.116, 0.247 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 5326, 1395, 1349 |
Rint | 0.036 |
(sin θ/λ)max (Å−1) | 0.595 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.027, 0.067, 1.11 |
No. of reflections | 1395 |
No. of parameters | 105 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.52, −0.90 |
Computer programs: SMART (Bruker, 1997), SAINT (Bruker, 1997), SHELXS97 (Sheldrick, 1990), SHELXL97 (Sheldrick, 1997), PLATON (Spek, 2003).
D—H···A | D—H | H···A | D···A | D—H···A |
N2—H2A···Cl1i | 0.86 | 2.49 | 3.321 (3) | 161 |
N3—H3A···N1ii | 0.90 | 2.22 | 3.086 (4) | 162 |
N3—H3B···Cl1iii | 0.90 | 2.59 | 3.379 (2) | 147 |
Symmetry codes: (i) x, −y, z+1/2; (ii) −x, −y, −z+1; (iii) −x, y−1, −z+1/2. |
Metallocrowns are cyclic polynuclear complexes, which are the inorganic analogues of crown ethers, both in structure and function (Bodwin et al., 2001). In contrast to the numerous 12-metallacrown-4 structures reported, there are only a few examples of ligands capable of forming planar rings of the 15-metallacrown-5 structure type. Especially α-amino- and picolinehydroxamic acids have been used as precursor ligands in the synthesis of these complexes (Seda et al., 2007; Parac-Vogt et al., 2006; Stemmler, Kampf et al., 1996; Stemmler, Barwinski et al., 1996).
The title compound was obtained unintentionally as a product of an attempted reaction of CdCl2·2.5H2O and picolinic acid hydrazide, in order to obtain a cadmium(II)-complex analogous to a 15-metallacrown-5, but with cadmium the only metal present. Here, picolinic acid hydrazide was used instead of various α-amino-, mandelo-, or picolinehydroxamic acids as a precursor ligand (Seda et al., 2007; Parac-Vogt et al., 2006; Stemmler, Kampf et al., 1996; Stemmler, Barwinski et al., 1996)
The asymmetric unit of the title compound consists of one-half molecule of the complex, with the CdII ion lying on a twofold rotation axis. The coordination geometry around the CdII ion can be considered as a slightly distorted octahedron, with two bidentate picolinic acid hydrazide ligands and two chloride anions (Fig. 1).
As observed in the structure of picolinic acid hydrazide (Zareef et al., 2006), the aromatic C—C bond lengths within the phenyl ring vary between 1.375 (5) Å and 1.388 (5) Å. Additionaly, an opening of the angles N1—C1—C2 (124.0 (3)°) and N1—C5—C4 (123.0 (3)°) is observed, due to the presence of the nitrogen atom, N1 (Zareef et al., 2006). As a consequence, a decrease of the ring angles C1—C2—C3 (117.8 (3)°), C2—C3—C4 (119.6 (3)°), C3—C4—C5 (118.5 (3)°) and C1—N1—C5 (117.1 (3)°) is noticed. The pyridine ring is twisted away with respect to the rest of the picolinic acid hydrazide molecule; the dihedral angle between the N1/C1—C5 and C1/C6/O1/N2/N3 is 23.3 (1)°.
In the crystal structure, intermolecular N—H···Cl and N—H···N hydrogen bonds link the molecules in to a two-dimensional network parallel to the (1 0 0) plane (Fig. 2). In addition, π-π stacking interactions are observed between the pyridine rings of the adjacent networks, with the distance between the ring centroids being 3.815 (2) or 3.693 (2) Å.
The reported structure is homologous to the structure of dichloro-bis(picolinic acid hydrazide)-mangenese (Tsintsadze et al., 1979) (reference code PHYZMN, CSD (Version 5.28) (Allen, 2002)).