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In the title complex, [FeCl2(C30H28N6)], the Fe atom is five-coordinated by two terminal chloride ligands and one end of the bis-tridentate ligand. The complexes display intermolecular C—H...π, π-stacking and C—H...X (X = N, Cl) interactions.

Supporting information

cif

Crystallographic Information File (CIF) https://doi.org/10.1107/S010827010001684X/na1490sup1.cif
Contains datablocks global, I

hkl

Structure factor file (CIF format) https://doi.org/10.1107/S010827010001684X/na1490Isup2.hkl
Contains datablock I

CCDC reference: 159981

Comment top

N,N,N',N'-Tetrakis(2-pyridylmethyl)benzene-1,4-diamine (1,4-tpbd) is capable of forming both mono- and dinuclear complexes (Buchen et al., 1997; Hazell et al., 1998). As well, the coordination of the octahedral metal ions as connectors between the tridentate bis(2-pyridylmethyl)amine ends of two 1,4-tpbd ligands should make possible the formation of one-dimensional coordination polymers. The title complex, (I), was obtained in the course of our efforts to access an iron(II)-containing polymer. Such a polymeric complex may be particularly interesting due to similarity of the N6 environment to well known mononuclear spin-crossover systems (Gütlich et al., 1994). The reaction of several iron(II) salts with 1,4-tpbd has lead to the precipitation of yellow powders which have shown a 1:1 ligand:metal stoichiometry by elemental analysis commensurable with either mononuclear or coordination polymeric structures (dinuclear could be excluded on this basis). The title compound was obtained as a yellow crystalline material from the reaction of iron(II) chloride with 1,4-tpbd and the structure reported here shows it to be monomeric. The cell parameters and space group are similar to the Zn analogue (Hazell et al., 1998), however the packing of the complexes in the two structures differs to some extent, and thus the two structures are not strictly isostructural. \sch

A search of the Cambridge Structural Database (update 5.19, April 2000; Allen & Kennard, 1993) reveals that it is only the third example of a pentacoordinated iron(II) with a N3Cl2 ligand set (Small et al., 1998; Britovsek et al., 1998; Hemmert et al., 1999). The geometry around the Fe atom (Table 1) is best described as being closer to square pyramidal (with Cl1 at the apex) than trigonal bipyramidal, although the geometry is more distorted from square pyramidal compared to the two other pentacoordinated iron(II) complexes with N3Cl2 coordination spheres. The sum of the C—N—C angles around the uncoordinated phenylenediamine nitrogen is 359.1 (9)°, and C16—N4 is only 1.386 (9) Å, indicating a π delocalization of this amine nitrogen atom lone pair with the aromatic system. In contrast, the corresponding values for the coordinated amine nitrogen atom are 335.8 (10) and 1.475 (8) Å, respectively.

The H-shaped complexes are interdigitated and display C—H···π interactions between a CH of a coordinated pyridyl ring of one complex and the benzene ring of another [closest contact: C4···C14iv = 3.620 (9) Å, H4A···C14iv = 2.69 Å, C4—H4A···C14iv = 165°, symmetry code: (iv) x + 1, y, z]. This pyridyl ring also engages in π-stacking interactions with a coordinated pyridyl of this second complex [closest non-hydrogen interaction: C5···C12iv = 3.34 (1) Å], which in turn engages in a π-stacking interaction with an uncoordinated pyridyl ring of a third complex [closest non-hydrogen interaction: C11···C24v = 3.28 (1) Å, symmetry code: (v) x, y, z + 1]. There are also a number of close C—H···X intermolecular contacts between both aromatic and aliphatic H atoms and the uncoordinated pyridyl N atoms and the chloride ligands which connect the complexes (Table 2).

Related literature top

For related literature, see: Allen & Kennard (1993); Britovsek et al. (1998); Buchen et al. (1997); Gütlich et al. (1994); Hazell et al. (1998); Hemmert et al. (1999); Small et al. (1998).

Experimental top

The title compound was prepared from the 1:1 reaction of anhydrous FeCl2 and 1,4-tpbd in acetonitrile under an inert atmosphere (Hazell et al., 1998). Yellow single crystals suitable for X-ray crystallography were obtained directly from the reaction mixture.

Computing details top

Data collection: COLLECT (Hooft, 1998); cell refinement: DENZO-SMN (Otwinowski & Minor, 1997); data reduction: DENZO-SMN; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEPIII (Burnett & Johnson, 1996); software used to prepare material for publication: SHELXL97.

Figures top
[Figure 1] Fig. 1. Atom-numbering scheme for (I). Displacement ellipsoids are drawn at the 50% probability level.
Dichloro[N,N,N',N'-tetrakis(2-pyridylmethyl)benzene-1,4-diamine]iron(II) top
Crystal data top
[FeCl2(C30H28N6)]F(000) = 620
Mr = 599.33Dx = 1.457 Mg m3
Monoclinic, P21Mo Kα radiation, λ = 0.71073 Å
a = 8.4470 (6) ÅCell parameters from 11554 reflections
b = 12.9100 (12) Åθ = 3.2–28.3°
c = 12.9850 (13) ŵ = 0.78 mm1
β = 105.270 (6)°T = 123 K
V = 1366.0 (2) Å3Irregular block, yellow
Z = 20.13 × 0.13 × 0.08 mm
Data collection top
Nonius KappaCCD
diffractometer
3608 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.110
Graphite monochromatorθmax = 28.3°, θmin = 3.2°
Detector resolution: 9 pixels mm-1h = 911
ϕ and ω scansk = 1217
11514 measured reflectionsl = 1717
5292 independent reflections
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.080H-atom parameters constrained
wR(F2) = 0.156 w = 1/[σ2(Fo2) + (0.0338P)2 + 3.2934P]
where P = (Fo2 + 2Fc2)/3
S = 1.06(Δ/σ)max = 0.001
5292 reflectionsΔρmax = 1.03 e Å3
352 parametersΔρmin = 0.66 e Å3
1 restraintAbsolute structure: Flack (1983), 1813 Friedel pairs
Primary atom site location: structure-invariant direct methodsAbsolute structure parameter: 0.01 (3)
Crystal data top
[FeCl2(C30H28N6)]V = 1366.0 (2) Å3
Mr = 599.33Z = 2
Monoclinic, P21Mo Kα radiation
a = 8.4470 (6) ŵ = 0.78 mm1
b = 12.9100 (12) ÅT = 123 K
c = 12.9850 (13) Å0.13 × 0.13 × 0.08 mm
β = 105.270 (6)°
Data collection top
Nonius KappaCCD
diffractometer
3608 reflections with I > 2σ(I)
11514 measured reflectionsRint = 0.110
5292 independent reflections
Refinement top
R[F2 > 2σ(F2)] = 0.080H-atom parameters constrained
wR(F2) = 0.156Δρmax = 1.03 e Å3
S = 1.06Δρmin = 0.66 e Å3
5292 reflectionsAbsolute structure: Flack (1983), 1813 Friedel pairs
352 parametersAbsolute structure parameter: 0.01 (3)
1 restraint
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 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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
Fe10.40540 (11)0.54750 (8)0.43159 (7)0.0200 (3)
Cl10.58024 (19)0.53142 (16)0.60247 (13)0.0278 (5)
Cl20.2987 (2)0.39034 (13)0.35798 (15)0.0277 (4)
N10.3807 (6)0.7149 (4)0.3814 (5)0.0171 (12)
C10.5486 (7)0.7511 (5)0.3777 (6)0.0204 (16)
H1A0.53790.81250.33060.024*
H1B0.61260.77160.45010.024*
C20.6369 (8)0.6666 (5)0.3365 (5)0.0188 (15)
C30.7674 (8)0.6892 (6)0.2918 (6)0.0283 (19)
H3A0.79510.75900.28120.034*
C40.8546 (9)0.6088 (7)0.2637 (6)0.0283 (19)
H4A0.94450.62260.23450.034*
C50.8103 (9)0.5079 (7)0.2782 (6)0.031 (2)
H5A0.86810.45110.25880.038*
C60.6779 (8)0.4916 (6)0.3221 (5)0.0236 (17)
H6A0.64600.42260.33200.028*
N20.5948 (6)0.5697 (4)0.3507 (4)0.0190 (14)
C70.3294 (8)0.7655 (6)0.4698 (6)0.0230 (17)
H7A0.29120.83680.44890.028*
H7B0.42380.76960.53380.028*
C80.1926 (8)0.7036 (5)0.4951 (5)0.0187 (15)
C90.0722 (8)0.7490 (6)0.5365 (6)0.0272 (18)
H9A0.06710.82200.54390.033*
C100.0408 (9)0.6843 (7)0.5668 (6)0.0308 (19)
H10A0.12280.71280.59630.037*
C110.0318 (9)0.5806 (7)0.5536 (6)0.034 (2)
H11A0.10760.53540.57340.041*
C120.0892 (7)0.5416 (8)0.5110 (5)0.0283 (16)
H12A0.09480.46890.50170.034*
N30.1985 (6)0.6018 (4)0.4822 (4)0.0187 (13)
C130.2610 (7)0.7263 (5)0.2764 (5)0.0162 (14)
C140.2437 (8)0.6473 (5)0.2013 (6)0.0185 (15)
H14A0.30610.58570.22000.022*
C150.1392 (8)0.6559 (5)0.1011 (6)0.0199 (15)
H15A0.13270.60140.05100.024*
C160.0399 (9)0.7462 (5)0.0715 (6)0.0202 (16)
C170.0588 (9)0.8243 (5)0.1481 (6)0.0235 (17)
H17A0.00530.88550.13150.028*
C180.1684 (8)0.8148 (5)0.2474 (6)0.0220 (16)
H18A0.18040.87040.29670.026*
N40.0702 (7)0.7538 (5)0.0284 (5)0.0262 (15)
C190.0808 (9)0.6716 (6)0.1053 (6)0.0290 (18)
H19A0.17590.68520.16700.035*
H19B0.10200.60560.07240.035*
C200.0722 (9)0.6585 (6)0.1459 (6)0.0252 (17)
C210.1731 (9)0.7411 (6)0.1506 (6)0.0323 (19)
H21A0.15050.80770.12700.039*
C220.3072 (10)0.7255 (7)0.1902 (6)0.037 (2)
H22A0.37720.78170.19540.044*
C230.3383 (10)0.6290 (7)0.2217 (6)0.039 (2)
H23A0.43070.61640.24860.047*
C240.2328 (10)0.5495 (9)0.2136 (5)0.0412 (19)
H24A0.25510.48200.23520.049*
N50.0991 (7)0.5636 (5)0.1762 (5)0.0327 (16)
C250.1533 (9)0.8509 (6)0.0635 (6)0.0273 (18)
H25A0.18460.85220.14250.033*
H25B0.07480.90820.03850.033*
C260.3064 (8)0.8711 (6)0.0252 (5)0.0227 (17)
C270.3662 (9)0.8030 (7)0.0356 (6)0.0312 (19)
H27A0.31250.73860.05570.037*
C280.5053 (9)0.8276 (7)0.0680 (7)0.037 (2)
H28A0.54930.78050.10940.044*
C290.5775 (9)0.9217 (7)0.0387 (7)0.036 (2)
H29A0.67060.94260.06150.043*
C300.5126 (9)0.9849 (6)0.0242 (6)0.0317 (19)
H30A0.56691.04850.04730.038*
N60.3754 (7)0.9623 (5)0.0555 (5)0.0284 (15)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Fe10.0167 (5)0.0202 (5)0.0235 (5)0.0023 (5)0.0059 (4)0.0021 (5)
Cl10.0207 (8)0.0401 (13)0.0216 (9)0.0080 (9)0.0037 (7)0.0032 (9)
Cl20.0295 (10)0.0221 (10)0.0276 (11)0.0037 (8)0.0005 (8)0.0008 (8)
N10.007 (2)0.019 (3)0.024 (3)0.006 (2)0.002 (2)0.001 (3)
C10.012 (3)0.021 (4)0.026 (4)0.008 (3)0.002 (3)0.001 (3)
C20.012 (3)0.026 (4)0.015 (4)0.001 (3)0.003 (3)0.008 (3)
C30.017 (4)0.040 (5)0.024 (4)0.007 (4)0.003 (3)0.013 (4)
C40.014 (4)0.046 (5)0.025 (4)0.005 (4)0.006 (3)0.005 (4)
C50.029 (4)0.043 (5)0.027 (4)0.006 (4)0.015 (4)0.001 (4)
C60.017 (4)0.033 (4)0.019 (4)0.000 (3)0.003 (3)0.004 (3)
N20.017 (3)0.020 (4)0.019 (3)0.002 (2)0.004 (2)0.001 (2)
C70.017 (3)0.026 (4)0.021 (4)0.002 (3)0.004 (3)0.006 (3)
C80.016 (3)0.023 (4)0.016 (4)0.003 (3)0.001 (3)0.002 (3)
C90.022 (4)0.030 (5)0.023 (4)0.011 (3)0.006 (3)0.004 (3)
C100.014 (4)0.051 (6)0.025 (4)0.006 (4)0.000 (3)0.002 (4)
C110.017 (3)0.062 (7)0.020 (4)0.001 (4)0.001 (3)0.003 (4)
C120.020 (3)0.034 (4)0.027 (4)0.003 (4)0.001 (3)0.003 (4)
N30.012 (3)0.028 (4)0.016 (3)0.000 (3)0.002 (2)0.002 (3)
C130.011 (3)0.020 (4)0.016 (4)0.002 (3)0.000 (3)0.003 (3)
C140.012 (3)0.015 (4)0.029 (4)0.001 (3)0.007 (3)0.005 (3)
C150.017 (3)0.022 (4)0.022 (4)0.001 (3)0.008 (3)0.000 (3)
C160.018 (3)0.022 (4)0.020 (4)0.007 (3)0.004 (3)0.012 (3)
C170.026 (4)0.021 (4)0.024 (4)0.003 (3)0.007 (3)0.004 (3)
C180.023 (4)0.016 (4)0.024 (4)0.003 (3)0.001 (3)0.000 (3)
N40.024 (3)0.030 (4)0.021 (3)0.000 (3)0.001 (3)0.001 (3)
C190.026 (4)0.040 (5)0.015 (4)0.001 (4)0.005 (3)0.000 (4)
C200.021 (4)0.031 (4)0.018 (4)0.006 (3)0.004 (3)0.001 (3)
C210.033 (4)0.043 (5)0.024 (4)0.007 (4)0.013 (4)0.005 (4)
C220.039 (5)0.041 (5)0.031 (5)0.005 (4)0.009 (4)0.003 (4)
C230.028 (4)0.065 (7)0.024 (5)0.012 (5)0.008 (4)0.004 (4)
C240.047 (5)0.045 (5)0.025 (4)0.021 (6)0.001 (4)0.006 (5)
N50.037 (3)0.034 (4)0.023 (3)0.002 (3)0.000 (3)0.003 (3)
C250.020 (4)0.036 (5)0.025 (4)0.008 (4)0.004 (3)0.009 (4)
C260.010 (3)0.036 (5)0.018 (4)0.004 (3)0.004 (3)0.001 (3)
C270.026 (4)0.039 (5)0.027 (5)0.003 (4)0.003 (4)0.011 (4)
C280.024 (4)0.049 (6)0.035 (5)0.013 (4)0.003 (4)0.006 (4)
C290.019 (4)0.043 (5)0.047 (5)0.004 (4)0.011 (4)0.001 (4)
C300.022 (4)0.029 (4)0.039 (5)0.012 (3)0.002 (4)0.000 (4)
N60.017 (3)0.029 (4)0.034 (4)0.001 (3)0.002 (3)0.005 (3)
Geometric parameters (Å, º) top
Fe1—N32.141 (5)C13—C141.391 (9)
Fe1—N22.152 (5)C14—C151.371 (9)
Fe1—N12.251 (6)C15—C161.428 (9)
Fe1—Cl22.321 (2)C16—N41.386 (9)
Fe1—Cl12.329 (2)C16—C171.396 (9)
N1—C131.475 (8)C17—C181.381 (9)
N1—C71.481 (9)N4—C191.444 (10)
N1—C11.506 (8)N4—C251.450 (9)
C1—C21.498 (9)C19—C201.529 (10)
C2—N21.326 (8)C20—N51.325 (10)
C2—C31.405 (9)C20—C211.376 (11)
C3—C41.377 (11)C21—C221.376 (11)
C4—C51.383 (10)C22—C231.359 (12)
C5—C61.399 (10)C23—C241.380 (13)
C6—N21.335 (8)C24—N51.354 (9)
C7—C81.511 (9)C25—C261.526 (10)
C8—N31.328 (8)C26—N61.327 (9)
C8—C91.398 (9)C26—C271.365 (10)
C9—C101.400 (11)C27—C281.385 (11)
C10—C111.355 (11)C28—C291.367 (11)
C11—C121.379 (10)C29—C301.367 (11)
C12—N31.334 (9)C30—N61.357 (9)
C13—C181.380 (9)
N3—Fe1—N2151.4 (2)C8—N3—C12119.3 (6)
N3—Fe1—N175.7 (2)C8—N3—Fe1115.1 (4)
N2—Fe1—N175.8 (2)C12—N3—Fe1125.2 (5)
N3—Fe1—Cl298.8 (2)C18—C13—C14117.9 (6)
N2—Fe1—Cl2100.0 (2)C18—C13—N1122.5 (6)
N1—Fe1—Cl2136.3 (2)C14—C13—N1119.6 (6)
N3—Fe1—Cl195.8 (2)C15—C14—C13121.9 (6)
N2—Fe1—Cl196.3 (2)C14—C15—C16120.4 (7)
N1—Fe1—Cl1110.4 (2)N4—C16—C17122.5 (6)
Cl2—Fe1—Cl1113.24 (8)N4—C16—C15120.7 (6)
C13—N1—C7113.7 (5)C17—C16—C15116.7 (7)
C13—N1—C1111.2 (5)C18—C17—C16121.5 (6)
C7—N1—C1110.9 (5)C13—C18—C17121.5 (6)
C13—N1—Fe1110.6 (4)C16—N4—C19120.0 (6)
C7—N1—Fe1102.9 (4)C16—N4—C25120.4 (6)
C1—N1—Fe1107.0 (4)C19—N4—C25118.7 (6)
C2—C1—N1110.3 (5)N4—C19—C20114.5 (6)
N2—C2—C3121.5 (7)N5—C20—C21123.1 (7)
N2—C2—C1117.4 (6)N5—C20—C19115.5 (7)
C3—C2—C1120.9 (6)C21—C20—C19121.3 (7)
C4—C3—C2119.0 (7)C20—C21—C22119.0 (8)
C3—C4—C5119.5 (6)C23—C22—C21119.3 (8)
C4—C5—C6118.1 (7)C22—C23—C24118.6 (8)
N2—C6—C5122.4 (7)N5—C24—C23122.9 (9)
C2—N2—C6119.5 (6)C20—N5—C24117.1 (8)
C2—N2—Fe1117.0 (4)N4—C25—C26115.3 (6)
C6—N2—Fe1123.2 (4)N6—C26—C27122.9 (6)
N1—C7—C8109.4 (5)N6—C26—C25113.5 (6)
N3—C8—C9121.2 (6)C27—C26—C25123.6 (7)
N3—C8—C7116.0 (5)C26—C27—C28120.0 (8)
C9—C8—C7122.6 (6)C29—C28—C27118.1 (8)
C8—C9—C10118.5 (7)C28—C29—C30118.5 (7)
C11—C10—C9119.3 (7)N6—C30—C29124.0 (7)
C10—C11—C12118.9 (8)C26—N6—C30116.4 (6)
N3—C12—C11122.8 (9)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C11—H11A···Cl1i0.952.763.556 (7)142
C23—H23A···Cl1ii0.952.803.666 (8)152
C25—H25A···Cl2iii0.992.753.730 (8)169
C17—H17A···N5iii0.952.553.42 (1)153
Symmetry codes: (i) x1, y, z; (ii) x, y, z1; (iii) x, y+1/2, z.

Experimental details

Crystal data
Chemical formula[FeCl2(C30H28N6)]
Mr599.33
Crystal system, space groupMonoclinic, P21
Temperature (K)123
a, b, c (Å)8.4470 (6), 12.9100 (12), 12.9850 (13)
β (°) 105.270 (6)
V3)1366.0 (2)
Z2
Radiation typeMo Kα
µ (mm1)0.78
Crystal size (mm)0.13 × 0.13 × 0.08
Data collection
DiffractometerNonius KappaCCD
diffractometer
Absorption correction
No. of measured, independent and
observed [I > 2σ(I)] reflections
11514, 5292, 3608
Rint0.110
(sin θ/λ)max1)0.666
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.080, 0.156, 1.06
No. of reflections5292
No. of parameters352
No. of restraints1
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)1.03, 0.66
Absolute structureFlack (1983), 1813 Friedel pairs
Absolute structure parameter0.01 (3)

Computer programs: COLLECT (Hooft, 1998), DENZO-SMN (Otwinowski & Minor, 1997), DENZO-SMN, SHELXS97 (Sheldrick, 1997), SHELXL97 (Sheldrick, 1997), ORTEPIII (Burnett & Johnson, 1996), SHELXL97.

Selected geometric parameters (Å, º) top
Fe1—N32.141 (5)Fe1—Cl22.321 (2)
Fe1—N22.152 (5)Fe1—Cl12.329 (2)
Fe1—N12.251 (6)
N3—Fe1—N2151.4 (2)N1—Fe1—Cl2136.3 (2)
N3—Fe1—N175.7 (2)N3—Fe1—Cl195.8 (2)
N2—Fe1—N175.8 (2)N2—Fe1—Cl196.3 (2)
N3—Fe1—Cl298.8 (2)N1—Fe1—Cl1110.4 (2)
N2—Fe1—Cl2100.0 (2)Cl2—Fe1—Cl1113.24 (8)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C11—H11A···Cl1i0.952.763.556 (7)142
C23—H23A···Cl1ii0.952.803.666 (8)152
C25—H25A···Cl2iii0.992.753.730 (8)169
C17—H17A···N5iii0.952.553.42 (1)153
Symmetry codes: (i) x1, y, z; (ii) x, y, z1; (iii) x, y+1/2, z.
 

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