catena-Poly[di-μ1,1-azido-(1,10-phenanthroline)cadmium(II)]

Feng Chen; Fa-Kun Zheng; Guang-Ning Liu; Mei-Feng Wu; Guo-Cong Guo

doi:10.1107/S1600536810019318

. 2010 Jun 9;66(Pt 7):m758. doi: 10.1107/S1600536810019318

catena-Poly[di-μ_1,1-azido-(1,10-phenanthroline)cadmium(II)]

Feng Chen ^a,^b, Fa-Kun Zheng ^a,^*, Guang-Ning Liu ^a,^b, Mei-Feng Wu ^a,^b, Guo-Cong Guo ^a

PMCID: PMC3006842 PMID: 21587693

Abstract

The asymmetric unit of the title Cd^II compound, [Cd(N₃)₂(C₁₂H₈N₂)]_n, contains a Cd^II atom, located on a twofold axis passing through the middle of the phenanthroline molecule, one azide ion and half of a 1,10-phenanthroline molecule. The Cd^II atom exhibits a distorted octahedral coordination including one chelating 1,10-phenanthroline ligand and four azide ligands. The crystal structure features chains along the c direction in which azide groups doubly bridge two adjacent Cd^II atoms in an end-on (EO) mode. Interchain π–π stacking interactions, with centroid–centroid separations of 3.408 (2) Å between the central aromatic rings of 1,10-phenanthroline molecules, lead to a supramolecular sheet parallel to the bc plane.

Related literature

For the structures of related metal-azido compounds, see: Goher et al. (2008 ▶); Ribas et al. (1999 ▶); Liu et al. (2007 ▶); Cano et al. (2005 ▶); Abu-Youssef et al. (2000 ▶); Bose et al. (2004 ▶); Mautner et al. (2010 ▶); Meyer et al. (2005 ▶); Gao et al. (2004 ▶).

Experimental

Crystal data

[Cd(N₃)₂(C₁₂H₈N₂)]
M _r = 376.67
Monoclinic,
a = 19.4591 (17) Å
b = 10.2988 (6) Å
c = 6.8151 (6) Å
β = 106.033 (4)°
V = 1312.66 (18) Å³
Z = 4
Mo Kα radiation
μ = 1.67 mm⁻¹
T = 293 K
0.30 × 0.20 × 0.18 mm

Data collection

Rigaku Mercury CCD diffractometer
Absorption correction: multi-scan (CrystalClear; Rigaku, 2002 ▶) T _min = 0.774, T _max = 1.000
4185 measured reflections
1217 independent reflections
1133 reflections with I > 2σ(I)
R _int = 0.023

Refinement

R[F ² > 2σ(F ²)] = 0.020
wR(F ²) = 0.056
S = 1.05
1217 reflections
96 parameters
H-atom parameters constrained
Δρ_max = 0.78 e Å⁻³
Δρ_min = −0.48 e Å⁻³

Data collection: CrystalClear (Rigaku, 2002 ▶); cell refinement: CrystalClear; data reduction: CrystalClear; 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.

Supplementary Material

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536810019318/dn2567sup1.cif

e-66-0m758-sup1.cif^{(14.6KB, cif)}

Structure factors: contains datablocks I. DOI: 10.1107/S1600536810019318/dn2567Isup2.hkl

e-66-0m758-Isup2.hkl^{(60.3KB, hkl)}

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

Acknowledgments

We gratefully acknowledge financial support from National Natural Science Foundation of China (20871115).

supplementary crystallographic information

Comment

Many compounds with uncommon magnetic properties have been widely investigated by using azido ligand, resulting from its rich coordination fashions (Ribas et al., 1999; Gao et al., 2004). The azido ligand exhibits a variety of bridging modes such as bi-dentate end-on (EO) and end-to-end (EE) bridging fashions (Liu et al., 2007; Cano et al., 2005; Goher et al., 2008; Mautner et al., 2010). A number of compounds with various structures have been obtained by introducing auxiliary ligands to the metal-azido system (Abu-Youssef et al., 2000; Bose et al., 2004; Meyer et al., 2005). The present example shows an infinite wavelike chain compound with 1,10-phenanthroline as an auxiliary ligand, [Cd(N₃)₂(C₁₂H₈N₂)], in which azido ligand adopts the EO mode.

The asymmetric unit of the title compound contains half a Cd^II ion, one azido ion and half a 1,10-phenanthroline molecule (Fig. 1). The Cd^II ion exhibits a distorted octahedral geometry, coordinated by one chelating 1,10-phenanthroline ligand and four azido ligands with the end-on (EO) mode. The distances of Cd—N vary from 2.306 (2) to 2.411 (3) Å . The azido ligands doubly bridge neighbouring Cd^II centers in the EO fashion, yielding an infinite wave-like Cd^II-azido chain along the c direction with the shortest Cd···Cd separation being 3.764 (3) Å.

The adjacent Cd^II-azido chains are mediated by interchained π-π stacking interactions between the aromatic rings of 1,10-phenanthroline molecules, which arrange in the opposite direction alternatively. The centroid-to-centroid distance between the central rings of the phenanthroline is 3.408 (2)Å and the centroid-to-plane distance is 3.28 Å leading to a slippage of 0.936Å. This π-π stacking builts up a 2-D supramolecular layer parallel to the bc plane (Fig. 2).

Experimental

A mixture of Cd(NO₃)₂.4H₂O (0.308 g, 1.00 mmol), NaN₃ (0.065 g, 1.00 mmol), Na(3-cba) (0.085 g, 0.50 mmol 3-Hcba = 3-cyanobenzoate acid), 1,10-phenanthroline (0.099 g, 0.50 mmol) and H₂O (8 ml) was placed in a Teflon-lined stainless container, and then heated at 453 K for 2 days, after cooled to room temperature for 2 days. Pale-yellow prism-shaped crystals of the title compound were obtained. IR peaks (KBr, cm^-1): 2053 s, 2037 s h, 1589 w, 1515 w, 1425 w, 1333 w, 1284 w, 846 m, 772 w, 727 m, 656 w. A strong band around 2053 cm^-1 indicates the presence of the azido group.