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Acta Cryst. (2009). E65, m44    [ doi:10.1107/S1600536808041354 ]

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

L. Yang and B. Tang

Abstract top

In the title compound, [Fe(C20H14N4O2)Cl], the FeIII 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 FeIII 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.

Comment top

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 FeIII center in the apical position. The geometry around the FeIII 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).

Related literature top

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

Experimental top

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)]+).

Refinement top

All H atoms were positioned geometrically and refined as riding, with C-H = 0.93 Å (aromatic) or 0.97 Å (methylene) and Uiso(H) = 1.2Ueq(C).

Computing details top

Data collection: SMART (Bruker, 1997); cell refinement: SAINT (Bruker, 1997); data reduction: SAINT (Bruker, 1997); 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 (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound. Displacement ellipsoids are drawn at the 30% probability level.
Chlorido{N,N'-o-phenylene-[6,6'-ethylenebis(pyridine-2-carboxamide)]}iron(III) top
Crystal data top
[Fe(C20H14N4O2)Cl]F(000) = 884
Mr = 433.65Dx = 1.600 Mg m−3
Monoclinic, P21/nMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ynCell parameters from 9989 reflections
a = 11.8532 (2) Åθ = 2.2–27.4°
b = 8.2028 (1) ŵ = 1.01 mm−1
c = 19.3507 (3) ÅT = 296 K
β = 106.889 (1)°Plate, black
V = 1800.31 (5) Å30.44 × 0.16 × 0.10 mm
Z = 4
Data collection top
Bruker SMART CCD area-detector
diffractometer		4142 independent reflections
Radiation source: fine-focus sealed tube3415 reflections with I > 2σ(I)
graphiteRint = 0.041
φ and ω scansθmax = 27.5°, θmin = 2.2°
Absorption correction: multi-scan
(SADABS, Sheldrick, 1996)		h = −15→15
Tmin = 0.778, Tmax = 1.000k = −10→10
24687 measured reflectionsl = −25→25
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.040Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.126H-atom parameters constrained
S = 1.00 w = 1/[σ2(Fo2) + (0.0642P)2 + 2.4383P]
where P = (Fo2 + 2Fc2)/3
4142 reflections(Δ/σ)max = 0.001
253 parametersΔρmax = 0.62 e Å−3
0 restraintsΔρmin = −0.43 e Å−3
Crystal data top
[Fe(C20H14N4O2)Cl]V = 1800.31 (5) Å3
Mr = 433.65Z = 4
Monoclinic, P21/nMo Kα radiation
a = 11.8532 (2) ŵ = 1.01 mm−1
b = 8.2028 (1) ÅT = 296 K
c = 19.3507 (3) Å0.44 × 0.16 × 0.10 mm
β = 106.889 (1)°
Data collection top
Bruker SMART CCD area-detector
diffractometer		4142 independent reflections
Absorption correction: multi-scan
(SADABS, Sheldrick, 1996)		3415 reflections with I > 2σ(I)
Tmin = 0.778, Tmax = 1.000Rint = 0.041
24687 measured reflectionsθmax = 27.5°
Refinement top
R[F2 > 2σ(F2)] = 0.040H-atom parameters constrained
wR(F2) = 0.126Δρmax = 0.62 e Å−3
S = 1.00Δρmin = −0.43 e Å−3
4142 reflectionsAbsolute structure: ?
253 parametersFlack parameter: ?
0 restraintsRogers parameter: ?
Special details top

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 F^2^ against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F^2^, conventional R-factors R are based on F, with F set to zero for negative F^2^. The threshold expression of F^2^ > σ(F^2^) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F^2^ are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
Fe10.45008 (3)0.56516 (5)0.62759 (2)0.02844 (13)
Cl10.49959 (7)0.48979 (10)0.74759 (4)0.0423 (2)
O10.1136 (2)0.6292 (4)0.61432 (18)0.0676 (8)
O20.5587 (2)0.2335 (3)0.51016 (14)0.0529 (6)
N10.2870 (2)0.5301 (3)0.59827 (14)0.0352 (5)
N20.4003 (2)0.7937 (3)0.64688 (12)0.0321 (5)
N30.6194 (2)0.5763 (3)0.62630 (12)0.0298 (5)
N40.44925 (19)0.3762 (3)0.57162 (12)0.0305 (5)
C10.2181 (3)0.6411 (4)0.61888 (17)0.0399 (7)
C20.2867 (3)0.7921 (4)0.64770 (16)0.0373 (6)
C30.2337 (3)0.9212 (4)0.67153 (19)0.0509 (9)
H3A0.15550.91560.67190.061*
C40.3014 (4)1.0606 (5)0.6950 (2)0.0564 (10)
H4A0.26961.14950.71270.068*
C50.4145 (4)1.0649 (4)0.69173 (18)0.0483 (8)
H5A0.45941.15850.70620.058*
C60.4643 (3)0.9306 (4)0.66690 (16)0.0377 (7)
C70.5853 (3)0.9393 (4)0.65875 (18)0.0443 (7)
H7A0.61591.04830.67160.053*
H7B0.58000.92220.60830.053*
C80.6751 (3)0.8146 (4)0.70492 (17)0.0418 (7)
H8A0.74680.87220.73010.050*
H8B0.64250.76830.74110.050*
C90.7061 (2)0.6787 (4)0.66208 (15)0.0352 (6)
C100.8207 (3)0.6559 (4)0.65877 (18)0.0453 (8)
H10A0.87940.72870.68240.054*
C110.8485 (3)0.5277 (5)0.62112 (19)0.0479 (8)
H11A0.92550.51240.61950.057*
C120.7599 (3)0.4217 (4)0.58564 (17)0.0413 (7)
H12A0.77600.33310.56000.050*
C130.6471 (2)0.4504 (3)0.58911 (15)0.0314 (6)
C140.5471 (2)0.3397 (4)0.55255 (15)0.0333 (6)
C150.2484 (2)0.3809 (4)0.56301 (16)0.0348 (6)
C160.1338 (3)0.3196 (4)0.5414 (2)0.0499 (8)
H16A0.07240.37730.55090.060*
C170.1128 (3)0.1721 (5)0.5056 (2)0.0590 (10)
H17A0.03640.13110.49050.071*
C180.2030 (3)0.0846 (4)0.4919 (2)0.0547 (9)
H18A0.1870−0.01530.46830.066*
C190.3178 (3)0.1438 (4)0.51280 (16)0.0414 (7)
H19A0.37890.08400.50410.050*
C200.3393 (2)0.2947 (3)0.54712 (15)0.0328 (6)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Fe10.0262 (2)0.0225 (2)0.0375 (2)−0.00026 (14)0.01073 (15)−0.00375 (15)
Cl10.0483 (4)0.0381 (4)0.0427 (4)0.0044 (3)0.0169 (3)0.0083 (3)
O10.0352 (13)0.0650 (18)0.109 (2)0.0042 (12)0.0307 (14)−0.0117 (17)
O20.0472 (13)0.0475 (14)0.0671 (15)0.0005 (11)0.0215 (11)−0.0268 (12)
N10.0278 (11)0.0299 (13)0.0484 (14)0.0000 (9)0.0119 (10)−0.0014 (10)
N20.0410 (13)0.0221 (11)0.0345 (12)0.0034 (10)0.0132 (10)−0.0013 (9)
N30.0287 (11)0.0274 (12)0.0334 (11)−0.0026 (9)0.0091 (9)−0.0020 (9)
N40.0301 (11)0.0237 (11)0.0370 (12)−0.0025 (9)0.0088 (9)−0.0049 (9)
C10.0337 (15)0.0377 (17)0.0515 (17)0.0065 (12)0.0175 (13)0.0020 (14)
C20.0424 (16)0.0333 (15)0.0396 (15)0.0099 (12)0.0173 (12)0.0021 (12)
C30.058 (2)0.047 (2)0.055 (2)0.0213 (17)0.0282 (17)0.0042 (16)
C40.083 (3)0.0406 (19)0.0494 (19)0.0225 (19)0.0254 (18)−0.0016 (15)
C50.076 (2)0.0272 (15)0.0401 (16)0.0053 (15)0.0136 (16)−0.0027 (13)
C60.0547 (18)0.0249 (14)0.0325 (14)0.0017 (13)0.0108 (12)0.0010 (11)
C70.0553 (19)0.0264 (15)0.0517 (18)−0.0103 (13)0.0166 (15)−0.0024 (13)
C80.0421 (16)0.0388 (17)0.0411 (16)−0.0095 (13)0.0069 (13)−0.0082 (13)
C90.0322 (14)0.0346 (15)0.0365 (14)−0.0063 (12)0.0066 (11)−0.0002 (12)
C100.0314 (15)0.051 (2)0.0500 (18)−0.0110 (14)0.0058 (13)0.0020 (15)
C110.0270 (14)0.063 (2)0.0540 (19)0.0007 (14)0.0126 (13)0.0059 (17)
C120.0330 (15)0.0472 (19)0.0462 (17)0.0054 (13)0.0154 (13)0.0001 (14)
C130.0311 (13)0.0311 (14)0.0321 (13)0.0019 (11)0.0092 (10)0.0020 (11)
C140.0339 (14)0.0296 (14)0.0360 (14)0.0024 (11)0.0094 (11)−0.0030 (11)
C150.0318 (14)0.0287 (14)0.0423 (15)−0.0045 (11)0.0084 (11)0.0036 (12)
C160.0325 (16)0.0450 (19)0.070 (2)−0.0058 (14)0.0115 (15)0.0041 (17)
C170.0431 (19)0.047 (2)0.079 (3)−0.0221 (16)0.0051 (17)0.0039 (19)
C180.063 (2)0.0346 (18)0.059 (2)−0.0211 (16)0.0073 (17)−0.0051 (15)
C190.0493 (18)0.0317 (16)0.0420 (16)−0.0082 (13)0.0114 (13)−0.0036 (13)
C200.0326 (14)0.0281 (14)0.0360 (14)−0.0047 (11)0.0073 (11)0.0012 (11)
Geometric parameters (Å, °) top
Fe1—N11.871 (2)C7—C81.557 (5)
Fe1—N41.889 (2)C7—H7A0.97
Fe1—N32.016 (2)C7—H7B0.97
Fe1—N22.032 (2)C8—C91.497 (4)
Fe1—Cl12.3080 (8)C8—H8A0.97
O1—C11.220 (4)C8—H8B0.97
O2—C141.231 (3)C9—C101.392 (4)
N1—C11.358 (4)C10—C111.373 (5)
N1—C151.412 (4)C10—H10A0.93
N2—C61.348 (4)C11—C121.383 (5)
N2—C21.350 (4)C11—H11A0.93
N3—C91.352 (4)C12—C131.378 (4)
N3—C131.353 (4)C12—H12A0.93
N4—C141.349 (4)C13—C141.498 (4)
N4—C201.418 (3)C15—C161.394 (4)
C1—C21.498 (5)C15—C201.396 (4)
C2—C31.378 (4)C16—C171.380 (5)
C3—C41.395 (6)C16—H16A0.93
C3—H3A0.93C17—C181.376 (6)
C4—C51.361 (6)C17—H17A0.93
C4—H4A0.93C18—C191.390 (5)
C5—C61.399 (4)C18—H18A0.93
C5—H5A0.93C19—C201.392 (4)
C6—C71.490 (5)C19—H19A0.93
N1—Fe1—N482.38 (10)C8—C7—H7B108.5
N1—Fe1—N3161.28 (10)H7A—C7—H7B107.5
N4—Fe1—N382.51 (9)C9—C8—C7114.1 (3)
N1—Fe1—N282.39 (10)C9—C8—H8A108.7
N4—Fe1—N2155.32 (10)C7—C8—H8A108.7
N3—Fe1—N2107.69 (10)C9—C8—H8B108.7
N1—Fe1—Cl1101.67 (8)C7—C8—H8B108.7
N4—Fe1—Cl1108.32 (8)H8A—C8—H8B107.6
N3—Fe1—Cl193.53 (7)N3—C9—C10120.1 (3)
N2—Fe1—Cl193.71 (7)N3—C9—C8118.3 (3)
C1—N1—C15125.8 (3)C10—C9—C8121.7 (3)
C1—N1—Fe1117.7 (2)C11—C10—C9121.0 (3)
C15—N1—Fe1116.19 (19)C11—C10—H10A119.5
C6—N2—C2119.0 (3)C9—C10—H10A119.5
C6—N2—Fe1130.7 (2)C10—C11—C12118.7 (3)
C2—N2—Fe1109.69 (19)C10—C11—H11A120.6
C9—N3—C13118.7 (2)C12—C11—H11A120.6
C9—N3—Fe1129.3 (2)C13—C12—C11118.4 (3)
C13—N3—Fe1111.65 (18)C13—C12—H12A120.8
C14—N4—C20125.7 (2)C11—C12—H12A120.8
C14—N4—Fe1118.49 (18)N3—C13—C12123.1 (3)
C20—N4—Fe1115.45 (18)N3—C13—C14115.6 (2)
O1—C1—N1127.6 (3)C12—C13—C14121.3 (3)
O1—C1—C2121.5 (3)O2—C14—N4127.6 (3)
N1—C1—C2110.8 (2)O2—C14—C13121.2 (3)
N2—C2—C3123.4 (3)N4—C14—C13111.2 (2)
N2—C2—C1116.0 (2)C16—C15—C20119.9 (3)
C3—C2—C1120.6 (3)C16—C15—N1127.5 (3)
C2—C3—C4117.6 (3)C20—C15—N1112.5 (2)
C2—C3—H3A121.2C17—C16—C15119.0 (3)
C4—C3—H3A121.2C17—C16—H16A120.5
C5—C4—C3119.1 (3)C15—C16—H16A120.5
C5—C4—H4A120.4C18—C17—C16121.1 (3)
C3—C4—H4A120.4C18—C17—H17A119.4
C4—C5—C6121.0 (3)C16—C17—H17A119.4
C4—C5—H5A119.5C17—C18—C19120.8 (3)
C6—C5—H5A119.5C17—C18—H18A119.6
N2—C6—C5119.8 (3)C19—C18—H18A119.6
N2—C6—C7119.2 (3)C18—C19—C20118.5 (3)
C5—C6—C7120.9 (3)C18—C19—H19A120.7
C6—C7—C8115.3 (3)C20—C19—H19A120.7
C6—C7—H7A108.5C19—C20—C15120.6 (3)
C8—C7—H7A108.5C19—C20—N4127.0 (3)
C6—C7—H7B108.5C15—C20—N4112.4 (2)
N4—Fe1—N1—C1−176.9 (2)C2—N2—C6—C7−173.6 (3)
N3—Fe1—N1—C1−140.5 (3)Fe1—N2—C6—C716.6 (4)
N2—Fe1—N1—C1−16.3 (2)C4—C5—C6—N2−1.0 (5)
Cl1—Fe1—N1—C175.9 (2)C4—C5—C6—C7175.9 (3)
N4—Fe1—N1—C159.6 (2)N2—C6—C7—C8−63.1 (4)
N3—Fe1—N1—C1546.0 (4)C5—C6—C7—C8119.9 (3)
N2—Fe1—N1—C15170.1 (2)C6—C7—C8—C9107.4 (3)
Cl1—Fe1—N1—C15−97.6 (2)C13—N3—C9—C101.6 (4)
N1—Fe1—N2—C6−173.7 (3)Fe1—N3—C9—C10174.0 (2)
N4—Fe1—N2—C6−121.4 (3)C13—N3—C9—C8−178.2 (3)
N3—Fe1—N2—C6−9.9 (3)Fe1—N3—C9—C8−5.7 (4)
Cl1—Fe1—N2—C685.0 (2)C7—C8—C9—N3−62.5 (4)
N1—Fe1—N2—C215.76 (19)C7—C8—C9—C10117.7 (3)
N4—Fe1—N2—C268.1 (3)N3—C9—C10—C11−1.8 (5)
N3—Fe1—N2—C2179.57 (18)C8—C9—C10—C11177.9 (3)
Cl1—Fe1—N2—C2−85.53 (19)C9—C10—C11—C120.7 (5)
N1—Fe1—N3—C9150.2 (3)C10—C11—C12—C130.6 (5)
N4—Fe1—N3—C9−173.5 (3)C9—N3—C13—C12−0.3 (4)
N2—Fe1—N3—C929.6 (3)Fe1—N3—C13—C12−174.0 (2)
Cl1—Fe1—N3—C9−65.4 (2)C9—N3—C13—C14178.4 (2)
N1—Fe1—N3—C13−37.0 (4)Fe1—N3—C13—C144.7 (3)
N4—Fe1—N3—C13−0.60 (19)C11—C12—C13—N3−0.8 (5)
N2—Fe1—N3—C13−157.53 (18)C11—C12—C13—C14−179.4 (3)
Cl1—Fe1—N3—C13107.44 (18)C20—N4—C14—O21.6 (5)
N1—Fe1—N4—C14164.8 (2)Fe1—N4—C14—O2−171.3 (3)
N3—Fe1—N4—C14−4.1 (2)C20—N4—C14—C13−179.7 (2)
N2—Fe1—N4—C14112.5 (3)Fe1—N4—C14—C137.5 (3)
Cl1—Fe1—N4—C14−95.4 (2)N3—C13—C14—O2171.0 (3)
N1—Fe1—N4—C20−8.8 (2)C12—C13—C14—O2−10.3 (4)
N3—Fe1—N4—C20−177.7 (2)N3—C13—C14—N4−7.8 (4)
N2—Fe1—N4—C20−61.1 (3)C12—C13—C14—N4170.9 (3)
Cl1—Fe1—N4—C2091.03 (19)C1—N1—C15—C161.3 (5)
C15—N1—C1—O14.1 (6)Fe1—N1—C15—C16174.3 (3)
Fe1—N1—C1—O1−168.8 (3)C1—N1—C15—C20178.5 (3)
C15—N1—C1—C2−174.1 (3)Fe1—N1—C15—C20−8.6 (3)
Fe1—N1—C1—C213.1 (3)C20—C15—C16—C171.3 (5)
C6—N2—C2—C3−3.4 (4)N1—C15—C16—C17178.3 (3)
Fe1—N2—C2—C3168.4 (3)C15—C16—C17—C180.7 (6)
C6—N2—C2—C1175.0 (3)C16—C17—C18—C19−1.0 (6)
Fe1—N2—C2—C1−13.2 (3)C17—C18—C19—C20−0.8 (5)
O1—C1—C2—N2−176.9 (3)C18—C19—C20—C152.8 (5)
N1—C1—C2—N21.3 (4)C18—C19—C20—N4−179.2 (3)
O1—C1—C2—C31.5 (5)C16—C15—C20—C19−3.1 (5)
N1—C1—C2—C3179.8 (3)N1—C15—C20—C19179.5 (3)
N2—C2—C3—C40.8 (5)C16—C15—C20—N4178.7 (3)
C1—C2—C3—C4−177.5 (3)N1—C15—C20—N41.3 (4)
C2—C3—C4—C51.6 (5)C14—N4—C20—C1915.3 (5)
C3—C4—C5—C6−1.5 (5)Fe1—N4—C20—C19−171.7 (2)
C2—N2—C6—C53.4 (4)C14—N4—C20—C15−166.7 (3)
Fe1—N2—C6—C5−166.4 (2)Fe1—N4—C20—C156.4 (3)
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
C3—H3A···Cl1i0.932.803.595 (4)144
C10—H10A···Cl1ii0.932.713.617 (3)165
C11—H11A···O1iii0.932.463.290 (5)149
Symmetry codes: (i) −x+1/2, y+1/2, −z+3/2; (ii) −x+3/2, y+1/2, −z+3/2; (iii) x+1, y, z.
Table 1
Selected geometric parameters (Å) top
Fe1—N11.871 (2)Fe1—N22.032 (2)
Fe1—N41.889 (2)Fe1—Cl12.3080 (8)
Fe1—N32.016 (2)
Table 2
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
C3—H3A···Cl1i0.932.803.595 (4)144
C10—H10A···Cl1ii0.932.713.617 (3)165
C11—H11A···O1iii0.932.463.290 (5)149
Symmetry codes: (i) −x+1/2, y+1/2, −z+3/2; (ii) −x+3/2, y+1/2, −z+3/2; (iii) x+1, y, z.
Acknowledgements top

The project was sponsored by the Foundation of Yibin University.

references
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