Chlorido{N,N′-o-phenyl­ene-[6,6′-ethyl­enebis(pyridine-2-carboxamide)]}iron(III)

Li Yang; Bin Tang

doi:10.1107/S1600536808041354

. 2008 Dec 10;65(Pt 1):m44. doi: 10.1107/S1600536808041354

Chlorido{N,N′-o-phenylene-[6,6′-ethylenebis(pyridine-2-carboxamide)]}iron(III)

Li Yang ^a,^*, Bin Tang ^b

PMCID: PMC2967889 PMID: 21581516

Abstract

In the title compound, [Fe(C₂₀H₁₄N₄O₂)Cl], the Fe^III ion is in a distorted square-pyramidal environment, with two pyridine and two deprotonated amide N atoms in the basal plane and the Cl ion in the apical position. The Fe^III ion is displaced from the basal plane of the square- pyramid towards the apical Cl atom by 0.2942 (4) Å. The molecules are linked into a three-dimensional network by C—H⋯Cl and C—H⋯O hydrogen bonds.

Related literature

For general background, see: Liu et al. (2006 ▶); Yang et al. (2007 ▶); Momenteau & Reed (1994 ▶). For related structures, see: Rath et al. (2004 ▶); Xu et al. (2007 ▶).

Experimental

Crystal data

[Fe(C₂₀H₁₄N₄O₂)Cl]
M _r = 433.65
Monoclinic,
a = 11.8532 (2) Å
b = 8.2028 (1) Å
c = 19.3507 (3) Å
β = 106.889 (1)°
V = 1800.31 (5) Å³
Z = 4
Mo Kα radiation
μ = 1.01 mm⁻¹
T = 296 (2) K
0.44 × 0.16 × 0.10 mm

Data collection

Bruker SMART CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS, Sheldrick, 1996 ▶) T _min = 0.778, T _max = 1.000 (expected range = 0.703–0.904)
24687 measured reflections
4142 independent reflections
3415 reflections with I > 2σ(I)
R _int = 0.041

Refinement

R[F ² > 2σ(F ²)] = 0.040
wR(F ²) = 0.126
S = 1.01
4142 reflections
253 parameters
H-atom parameters constrained
Δρ_max = 0.62 e Å⁻³
Δρ_min = −0.43 e Å⁻³

Data collection: SMART (Bruker, 1997 ▶); cell refinement: SAINT (Bruker, 1997 ▶); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: SHELXTL (Sheldrick, 2008 ▶); software used to prepare material for publication: SHELXTL.

Supplementary Material

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536808041354/ci2736sup1.cif

e-65-00m44-sup1.cif^{(22.4KB, cif)}

Structure factors: contains datablocks I. DOI: 10.1107/S1600536808041354/ci2736Isup2.hkl

e-65-00m44-Isup2.hkl^{(203KB, hkl)}

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

Table 1. Selected bond lengths (Å).

Fe1—N1	1.871 (2)
Fe1—N4	1.889 (2)
Fe1—N3	2.016 (2)
Fe1—N2	2.032 (2)
Fe1—Cl1	2.3080 (8)

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Table 2. Hydrogen-bond geometry (Å, °).

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C3—H3A⋯Cl1ⁱ	0.93	2.80	3.595 (4)	144
C10—H10A⋯Cl1ⁱⁱ	0.93	2.71	3.617 (3)	165
C11—H11A⋯O1ⁱⁱⁱ	0.93	2.46	3.290 (5)	149

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Symmetry codes: (i) Inline graphic ; (ii) ; (iii) .

Acknowledgments

The project was sponsored by the Foundation of Yibin University.

supplementary crystallographic information

Comment

The chemistry of macrocyclic complexes has attracted the interest of both inorganic and bioinorganic chemists in recent years. Iron(III) complexes are involved in numerous biological redox reactions performed by metalloenzymes (Momenteau et al., 1994). As part of our studies on catalysis by N4 non-porphyrin complexes (Liu et al., 2006; Yang et al., 2007), we report here the crystal structure of a iron(III) complex with 1,2-[bis(6'-pyridine-2'-carboxamido)-ethane]benzene.

As shown in Fig.1, the complex has a five-coordinate structure with two pyridine and two deprotonated amide N atoms in the basal plane while the Cl ion is bonded to the Fe^III center in the apical position. The geometry around the Fe^III ion is approximately square-pyramidal. The Fe—N(amide) distances are shorter than the Fe—N(pyridine) distances (Table 1), both of which are shorter than the Fe—N distances found in the non-ring related Fe—N4 complexes such as [NEt₄][Fe(bbpc)Cl₂][H₂bbpc is N,N'-(4,5-dichloro-o-phenylene)bis(4-tertbutylpyridine-2-carboxamide)] (Xu et al., 2007). The Fe—Cl distance of 2.3080 (8) Å is slightly shorter than that observed in [Fe(bbpc)Cl₂](Et₄N) (2.3299 (9) Å and 2.3880 (9) Å), while it is longer than that in [FeCl(meso-NH₂-octaethylporphyrin)] (2.2596 (8) Å, Sankar et al., 2004).

In the crystalline state, the molecules are linked into a three-dimensional network by C—H···Cl and C—H···O hydrogen bonds (Table 2).

Experimental

1,2-[Bis(6'-pyridine-2'carboxamido)-ethane]benzene (132 mg, 0.38 mmol) and sodium acetate (80 mg, 0.76 mmol) were added to a stirred solution of FeCl₃.6H₂O (244 mg, 0.9 mmol) in CH₃OH (20 ml). The colour of the mixture turned green almost immediately. The mixture was refluxed for 3 h and dark green microcrystals appeared. They were collected by filtration, washed with methanol, and air-dried. (123 mg, yield 75%). Single crystals suitable for X-ray diffraction were grown via diffusion of Et₂O into a DMF solution of the complex. Selected IR data (KBr, cm^-1):ν=1629 (C=O), 1602 (C—N), 1572, 1346, 1287, 1142, 1083, 1081, 762. MS (FAB): 398.3([Fe(bpeb)]⁺).