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Acta Crystallogr Sect E Struct Rep Online. 2008 October 1; 64(Pt 10): m1243–m1244.
Published online 2008 September 6. doi:  10.1107/S1600536808027153
PMCID: PMC2959433

catena-Poly[[aqua­(dipyrido[3,2-a:2′,3′-c]phenazine-κ2 N 4,N 5)iron(II)]-μ-pyrazine-2,3-dicarboxyl­ato-κ3 N 1,O 2:O 3]

Abstract

In the title compound, [Fe(C6H2N2O4)(C18H10N4)(H2O)]n, the FeII ion adopts a slightly distorted octahedral mer-FeN3O3 geometry, arising from one N,N′-bidentate dipyrido[3,2-a:2′,3′-c]phenazine ligand, one N,O-chelating pyrazine-2,3-dicarboxyl­ate dianion and one water mol­ecule. An O-bonded symmetry-related dianion completes the coordination of the metal. The bridging dianion results in a one-dimensional polymeric chain. Aromatic π–π stacking inter­actions between ligands [centroid–centroid separations = 3.528 (2) and 3.741 (2) Å] and O—H(...)O and O—H(...)N hydrogen bonds link the chains together, leading to a three-dimensional supra­molecular network.

Related literature

For related literature, see: Che et al. (2006 [triangle]); Stephenson & Hardie (2006 [triangle]); Wang et al. (2008 [triangle]); Xu et al. (2008 [triangle]).

An external file that holds a picture, illustration, etc.
Object name is e-64-m1243-scheme1.jpg

Experimental

Crystal data

  • [Fe(C6H2N2O4)(C18H10N4)(H2O)]
  • M r = 522.26
  • Triclinic, An external file that holds a picture, illustration, etc.
Object name is e-64-m1243-efi1.jpg
  • a = 6.7868 (14) Å
  • b = 7.4586 (15) Å
  • c = 20.548 (4) Å
  • α = 90.75 (3)°
  • β = 95.89 (3)°
  • γ = 98.54 (3)°
  • V = 1022.8 (4) Å3
  • Z = 2
  • Mo Kα radiation
  • μ = 0.79 mm−1
  • T = 292 (2) K
  • 0.35 × 0.30 × 0.25 mm

Data collection

  • Rigaku R-AXIS RAPID diffractometer
  • Absorption correction: multi-scan (ABSCOR; Higashi, 1995 [triangle]) T min = 0.756, T max = 0.821
  • 10101 measured reflections
  • 4633 independent reflections
  • 2914 reflections with I > 2σ(I)
  • R int = 0.056

Refinement

  • R[F 2 > 2σ(F 2)] = 0.056
  • wR(F 2) = 0.129
  • S = 1.04
  • 4633 reflections
  • 333 parameters
  • H atoms treated by a mixture of independent and constrained refinement
  • Δρmax = 0.47 e Å−3
  • Δρmin = −0.45 e Å−3

Data collection: PROCESS-AUTO (Rigaku, 1998 [triangle]); cell refinement: PROCESS-AUTO; data reduction: PROCESS-AUTO; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 [triangle]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 [triangle]); molecular graphics: SHELXTL-Plus (Sheldrick, 2008 [triangle]); software used to prepare material for publication: SHELXL97.

Table 1
Selected bond lengths (Å)
Table 2
Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536808027153/hb2771sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536808027153/hb2771Isup2.hkl

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

Acknowledgments

The authors thank the Doctoral Foundation of Jilin Normal University (No. 2006006 and No. 2007009) and the Subject and Base Construction Foundation of Jilin Normal University (No. 2006041).

supplementary crystallographic information

Comment

Dipyrido[3,2-a:2',3'-c]phenazine (DPPZ) is an important derivative of 1,10-phenanthroline (phen), having often been used to build novel supramolecular architectures due to its excellent coordinating ability to metals and its rigid planar aromatic ring system (Stephenson & Hardie, 2006). A few complexes containing DPPZ in combination with doubly-deprotonated pyrazine-2,3-dicarboxylic acid (H2PZDC) have been reported (Xu et al., 2008; Wang et al., 2008). As a continuation of this work, we selected H2PZDC as a linker ligand and DPPZ as a secondary chelating ligand, generating a new coordination polymer, [Fe(DPPZ)(PZDC)(H2O)]n, (I), which is reported here.

The Fe(II) atom is bonded to three nitrogen atoms (N1, N2, N5) from one DPPZ ligand and one PZDC ligand, and three oxygen atoms (O1, O3i, O1W) from two PZDC ligands and one water molecule in a slightly distorted octahedral coordination geometry (Table 1). The mean bond distances are Fe—N = 2.175 (3) Å and Fe—O = 2.101 (3) Å. The N1, N2, N5, O1W atoms comprise the basal plane, while the O1 and O3 atoms occupy the axial position (Fig. 1). The PZDC2- dianion adopts chelating and bridging coordination modes, linking the adjacent Fe atoms into a distinctive one-dimensional chain propagating along the b axis, and the DPPZ ligands are attached to one side of the chain. The neighboring one-dimensional chains interact by π-π stacking between the dppz ligands [centroid separation = 3.741 (2) Å], at the same time, the π-π type interactions between two PZDC2- ligands occur [centroid separation = 3.528 (2) Å]. In this way, these neighboring one-dimensional chains are linked into an intriguing three-dimensional supramolecular motif (Fig. 2). Furthermore, O—H···O and O—H···N hydrogen bonds between the O1W atom and the O4, N6 atoms of the PZDC2- dianion further consolidate the three-dimensional architecture (Table 2).

Experimental

The DPPZ ligand was synthesized according to the literature method (Che, Li et al., 2006). A mixture of DPPZ, H2PZDC, FeSO4 and water in a molar ratio of 1:1:1:5000 was sealed in a Teflon-lined autoclave and heated to 433 K for 3 d. Upon cooling and opening the bomb, brown blocks of (I) were obtained (75% yield based on Fe).

Refinement

All H atoms on C atoms were positioned geometrically (C—H = 0.93 Å) and refined as riding, with Uiso(H)= 1.2Ueq(C). The hydrogen atoms of water molecules were located from difference Fourier maps and their positions and Uiso values were refined freely.

Figures

Fig. 1.
The asymmetric unit of (I), expanded to show the metal coordination sphere. Displacement ellipsoids are drawn at the 20% probability level (arbitrary spheres for the H atoms). [Symmetry code: (i) x, y + 1, z.]
Fig. 2.
Packing diagram of the three-dimensional supramolecular structure of (I) formed viaπ-π interactions. H atoms have been omitted.

Crystal data

[Fe(C6H2N2O4)(C18H10N4)(H2O)]Z = 2
Mr = 522.26F(000) = 532
Triclinic, P1Dx = 1.696 Mg m3
Hall symbol: -P 1Mo Kα radiation, λ = 0.71073 Å
a = 6.7868 (14) ÅCell parameters from 2687 reflections
b = 7.4586 (15) Åθ = 3.0–27.5°
c = 20.548 (4) ŵ = 0.79 mm1
α = 90.75 (3)°T = 292 K
β = 95.89 (3)°Block, brown
γ = 98.54 (3)°0.35 × 0.30 × 0.25 mm
V = 1022.8 (4) Å3

Data collection

Rigaku R-AXIS RAPID diffractometer4633 independent reflections
Radiation source: fine-focus sealed tube2914 reflections with I > 2σ(I)
graphiteRint = 0.056
Detector resolution: 10.0 pixels mm-1θmax = 27.5°, θmin = 3.0°
ω scansh = −8→8
Absorption correction: multi-scan (ABSCOR; Higashi, 1995)k = −9→8
Tmin = 0.756, Tmax = 0.821l = −25→26
10101 measured reflections

Refinement

Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.056Hydrogen site location: difmap and geom
wR(F2) = 0.129H atoms treated by a mixture of independent and constrained refinement
S = 1.04w = 1/[σ2(Fo2) + (0.0428P)2 + 1.0171P] where P = (Fo2 + 2Fc2)/3
4633 reflections(Δ/σ)max = 0.004
333 parametersΔρmax = 0.47 e Å3
0 restraintsΔρmin = −0.45 e Å3

Special details

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)

xyzUiso*/Ueq
C1−0.3579 (6)0.3353 (5)0.21577 (19)0.0391 (10)
H1−0.41340.27420.17690.047*
C2−0.4714 (6)0.3250 (5)0.26882 (19)0.0399 (10)
H2−0.59900.25750.26570.048*
C3−0.3893 (6)0.4177 (5)0.32583 (19)0.0391 (9)
H3−0.46250.41470.36180.047*
C4−0.1974 (5)0.5158 (5)0.32993 (17)0.0309 (8)
C5−0.1015 (6)0.6154 (5)0.38923 (17)0.0324 (8)
C6−0.1076 (7)0.7026 (5)0.49600 (18)0.0410 (10)
C7−0.2116 (8)0.7065 (6)0.5526 (2)0.0536 (12)
H7−0.34330.64930.55170.064*
C8−0.1156 (8)0.7952 (6)0.6082 (2)0.0563 (13)
H8−0.18290.79770.64540.068*
C90.0830 (8)0.8825 (6)0.6102 (2)0.0545 (13)
H90.14540.94150.64870.065*
C100.1856 (7)0.8821 (6)0.55679 (19)0.0478 (11)
H100.31720.94040.55880.057*
C110.0912 (7)0.7924 (5)0.49774 (18)0.0391 (10)
C120.0969 (6)0.7099 (5)0.39062 (18)0.0350 (9)
C130.2008 (6)0.7143 (5)0.33132 (17)0.0324 (8)
C140.3877 (6)0.8170 (5)0.3279 (2)0.0431 (10)
H140.45200.88620.36400.052*
C150.4771 (6)0.8157 (5)0.2708 (2)0.0422 (10)
H150.59980.88730.26730.051*
C160.3807 (6)0.7056 (5)0.21845 (19)0.0370 (9)
H160.44380.70160.18050.044*
C170.1100 (6)0.6141 (5)0.27547 (17)0.0305 (8)
C18−0.0933 (5)0.5160 (5)0.27466 (17)0.0293 (8)
C19−0.2089 (6)0.2259 (5)0.01794 (18)0.0336 (9)
H19−0.22070.34000.00160.040*
C20−0.2698 (6)0.0736 (5)−0.02246 (18)0.0365 (9)
H20−0.31640.0881−0.06600.044*
C21−0.1979 (5)−0.1099 (5)0.06260 (18)0.0303 (8)
C22−0.1288 (5)0.0440 (5)0.10284 (17)0.0285 (8)
C23−0.0384 (6)0.0397 (5)0.17379 (18)0.0346 (9)
C24−0.2043 (5)−0.2964 (5)0.08552 (16)0.0297 (8)
N1−0.1746 (5)0.4280 (4)0.21800 (14)0.0331 (7)
N20.2019 (5)0.6055 (4)0.22036 (14)0.0314 (7)
N3−0.2043 (5)0.6123 (4)0.44118 (15)0.0411 (8)
N40.1938 (5)0.7950 (4)0.44469 (15)0.0392 (8)
N5−0.1343 (5)0.2118 (4)0.07921 (14)0.0305 (7)
N6−0.2634 (5)−0.0942 (4)−0.00061 (15)0.0352 (8)
O10.0834 (4)0.1821 (3)0.19258 (13)0.0424 (7)
O2−0.0907 (5)−0.0942 (4)0.20571 (14)0.0510 (8)
O1W0.2777 (5)0.4031 (4)0.08593 (15)0.0452 (8)
O3−0.0399 (4)−0.3617 (3)0.09209 (12)0.0375 (6)
O4−0.3708 (5)−0.3852 (4)0.09181 (15)0.0550 (9)
Fe0.03575 (9)0.42245 (7)0.14403 (3)0.03090 (17)
HW1B0.402 (10)0.456 (8)0.081 (3)0.10 (2)*
HW1A0.279 (7)0.315 (7)0.063 (2)0.056 (15)*

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
C10.039 (2)0.038 (2)0.036 (2)−0.0039 (18)−0.0006 (17)−0.0008 (18)
C20.030 (2)0.041 (2)0.044 (2)−0.0067 (18)0.0026 (17)0.0041 (19)
C30.041 (2)0.044 (2)0.033 (2)0.0053 (19)0.0061 (17)0.0035 (18)
C40.029 (2)0.0298 (19)0.0337 (19)0.0028 (16)0.0041 (16)0.0019 (16)
C50.040 (2)0.0282 (19)0.0289 (18)0.0044 (16)0.0051 (16)0.0016 (16)
C60.056 (3)0.037 (2)0.031 (2)0.011 (2)0.0028 (18)0.0013 (17)
C70.070 (3)0.051 (3)0.041 (2)0.007 (2)0.015 (2)0.000 (2)
C80.090 (4)0.051 (3)0.032 (2)0.021 (3)0.015 (2)−0.005 (2)
C90.085 (4)0.045 (3)0.033 (2)0.015 (3)−0.002 (2)−0.006 (2)
C100.059 (3)0.046 (3)0.036 (2)0.010 (2)−0.005 (2)−0.008 (2)
C110.053 (3)0.033 (2)0.031 (2)0.0098 (19)0.0004 (18)−0.0010 (17)
C120.041 (2)0.0308 (19)0.0328 (19)0.0059 (17)0.0011 (17)0.0008 (16)
C130.035 (2)0.0278 (18)0.0330 (19)−0.0015 (16)0.0030 (16)−0.0010 (16)
C140.043 (3)0.040 (2)0.042 (2)−0.0042 (19)0.0025 (19)−0.0093 (19)
C150.038 (2)0.036 (2)0.049 (2)−0.0087 (18)0.0076 (19)−0.0047 (19)
C160.035 (2)0.034 (2)0.042 (2)−0.0001 (17)0.0087 (17)0.0003 (18)
C170.030 (2)0.0255 (18)0.0344 (19)−0.0007 (15)0.0022 (15)0.0026 (15)
C180.029 (2)0.0276 (18)0.0294 (18)0.0002 (15)0.0014 (15)0.0032 (15)
C190.034 (2)0.0312 (19)0.036 (2)0.0045 (16)0.0067 (17)0.0019 (16)
C200.036 (2)0.042 (2)0.0302 (19)0.0026 (18)0.0027 (16)−0.0011 (17)
C210.0236 (19)0.0274 (18)0.040 (2)0.0028 (15)0.0058 (16)−0.0001 (16)
C220.028 (2)0.0237 (17)0.0336 (19)0.0007 (15)0.0061 (15)−0.0034 (15)
C230.039 (2)0.030 (2)0.0343 (19)0.0043 (17)0.0038 (17)0.0022 (17)
C240.025 (2)0.038 (2)0.0240 (17)−0.0043 (16)0.0053 (15)−0.0002 (15)
N10.0338 (18)0.0331 (16)0.0300 (15)−0.0017 (14)0.0028 (13)−0.0009 (14)
N20.0305 (18)0.0305 (16)0.0324 (16)0.0011 (13)0.0048 (13)0.0000 (13)
N30.050 (2)0.0378 (19)0.0347 (17)0.0026 (16)0.0059 (16)0.0009 (15)
N40.046 (2)0.0376 (18)0.0330 (17)0.0071 (16)0.0007 (15)−0.0060 (15)
N50.0311 (18)0.0252 (15)0.0344 (16)0.0002 (13)0.0062 (13)−0.0005 (13)
N60.0367 (19)0.0315 (17)0.0354 (17)−0.0023 (14)0.0055 (14)−0.0050 (14)
O10.0450 (17)0.0328 (15)0.0445 (16)0.0000 (13)−0.0099 (13)0.0003 (13)
O20.068 (2)0.0383 (16)0.0451 (16)0.0004 (15)0.0098 (15)0.0096 (14)
O1W0.0364 (18)0.0424 (17)0.0549 (18)−0.0070 (14)0.0172 (14)−0.0195 (15)
O30.0453 (18)0.0302 (14)0.0388 (14)0.0069 (12)0.0114 (13)0.0064 (12)
O40.047 (2)0.0442 (17)0.068 (2)−0.0158 (15)0.0120 (16)0.0024 (15)
Fe0.0342 (3)0.0253 (3)0.0314 (3)−0.0014 (2)0.0042 (2)−0.0020 (2)

Geometric parameters (Å, °)

C1—N11.326 (5)C15—H150.9300
C1—C21.395 (5)C16—N21.331 (5)
C1—H10.9300C16—H160.9300
C2—C31.375 (5)C17—N21.353 (4)
C2—H20.9300C17—C181.461 (5)
C3—C41.390 (5)C18—N11.353 (4)
C3—H30.9300C19—N51.319 (5)
C4—C181.398 (5)C19—C201.384 (5)
C4—C51.460 (5)C19—H190.9300
C5—N31.332 (5)C20—N61.340 (5)
C5—C121.421 (5)C20—H200.9300
C6—N31.360 (5)C21—N61.341 (5)
C6—C111.412 (6)C21—C221.399 (5)
C6—C71.423 (6)C21—C241.471 (5)
C7—C81.368 (6)C22—N51.353 (4)
C7—H70.9300C22—C231.525 (5)
C8—C91.403 (7)C23—O21.230 (4)
C8—H80.9300C23—O11.274 (4)
C9—C101.360 (6)C24—O41.242 (4)
C9—H90.9300C24—O31.278 (5)
C10—C111.422 (5)Fe—N52.160 (3)
C10—H100.9300Fe—N22.172 (3)
C11—N41.351 (5)Fe—N12.193 (3)
C12—N41.333 (5)Fe—O3i2.042 (3)
C12—C131.468 (5)Fe—O12.113 (3)
C13—C141.390 (5)Fe—O1W2.148 (3)
C13—C171.397 (5)O1W—HW1B0.89 (7)
C14—C151.375 (6)O1W—HW1A0.81 (5)
C14—H140.9300O3—Feii2.042 (3)
C15—C161.391 (5)
N1—C1—C2123.2 (3)N1—C18—C17116.7 (3)
N1—C1—H1118.4C4—C18—C17121.0 (3)
C2—C1—H1118.4N5—C19—C20121.1 (4)
C3—C2—C1118.0 (4)N5—C19—H19119.5
C3—C2—H2121.0C20—C19—H19119.5
C1—C2—H2121.0N6—C20—C19121.8 (4)
C2—C3—C4120.2 (4)N6—C20—H20119.1
C2—C3—H3119.9C19—C20—H20119.1
C4—C3—H3119.9N6—C21—C22120.8 (3)
C3—C4—C18117.8 (3)N6—C21—C24115.7 (3)
C3—C4—C5122.8 (3)C22—C21—C24123.5 (3)
C18—C4—C5119.4 (3)N5—C22—C21120.4 (3)
N3—C5—C12122.0 (3)N5—C22—C23115.0 (3)
N3—C5—C4118.1 (3)C21—C22—C23124.6 (3)
C12—C5—C4120.0 (3)O2—C23—O1128.1 (4)
N3—C6—C11121.7 (4)O2—C23—C22118.3 (3)
N3—C6—C7118.6 (4)O1—C23—C22113.5 (3)
C11—C6—C7119.7 (4)O4—C24—O3124.1 (4)
C8—C7—C6119.2 (5)O4—C24—C21117.9 (4)
C8—C7—H7120.4O3—C24—C21117.6 (3)
C6—C7—H7120.4C1—N1—C18118.4 (3)
C7—C8—C9121.0 (4)C1—N1—Fe126.7 (2)
C7—C8—H8119.5C18—N1—Fe114.2 (2)
C9—C8—H8119.5C16—N2—C17118.2 (3)
C10—C9—C8121.0 (4)C16—N2—Fe127.2 (2)
C10—C9—H9119.5C17—N2—Fe114.6 (2)
C8—C9—H9119.5C5—N3—C6116.2 (4)
C9—C10—C11119.8 (4)C12—N4—C11116.6 (4)
C9—C10—H10120.1C19—N5—C22118.3 (3)
C11—C10—H10120.1C19—N5—Fe128.0 (3)
N4—C11—C6121.6 (3)C22—N5—Fe112.6 (2)
N4—C11—C10119.3 (4)C20—N6—C21117.4 (3)
C6—C11—C10119.1 (4)C23—O1—Fe116.1 (2)
N4—C12—C5121.9 (3)Fe—O1W—HW1B141 (4)
N4—C12—C13118.3 (3)Fe—O1W—HW1A122 (3)
C5—C12—C13119.8 (3)HW1B—O1W—HW1A97 (5)
C14—C13—C17117.8 (3)C24—O3—Feii130.2 (2)
C14—C13—C12122.5 (3)O3i—Fe—O1173.46 (11)
C17—C13—C12119.7 (3)O3i—Fe—O1W90.86 (12)
C15—C14—C13119.7 (4)O1—Fe—O1W91.40 (13)
C15—C14—H14120.1O3i—Fe—N597.15 (12)
C13—C14—H14120.1O1—Fe—N576.90 (11)
C14—C15—C16118.8 (4)O1W—Fe—N585.84 (12)
C14—C15—H15120.6O3i—Fe—N290.36 (11)
C16—C15—H15120.6O1—Fe—N295.42 (11)
N2—C16—C15122.8 (4)O1W—Fe—N297.75 (12)
N2—C16—H16118.6N5—Fe—N2171.65 (12)
C15—C16—H16118.6O3i—Fe—N197.51 (12)
N2—C17—C13122.5 (3)O1—Fe—N180.95 (12)
N2—C17—C18117.4 (3)O1W—Fe—N1169.62 (13)
C13—C17—C18120.0 (3)N5—Fe—N199.12 (11)
N1—C18—C4122.3 (3)N2—Fe—N176.17 (11)

Symmetry codes: (i) x, y+1, z; (ii) x, y−1, z.

Hydrogen-bond geometry (Å, °)

D—H···AD—HH···AD···AD—H···A
O1W—HW1B···O4iii0.89 (7)1.79 (7)2.649 (4)161 (5)
O1W—HW1A···N6iv0.81 (5)2.05 (5)2.861 (4)176 (5)

Symmetry codes: (iii) x+1, y+1, z; (iv) −x, −y, −z.

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: HB2771).

References

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