metal-organic compounds
Retracted: Diaquabis(pyridine-2-carboxylato-κ2N,O)iron(II)
aInstitute of Applied Materials, College of Resource & Environmental Management, Jiangxi University of Finance & Economics, Nanchang, Jiangxi 330013, People's Republic of China, and bDepartment of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, Fujian 361005, People's Republic of China
*Correspondence e-mail: guohuaxia09@126.com
The FeII atom in the title complex, [Fe(C6H4NO2)2(H2O)2], exists in a distorted octahedral coordination geometry defined by two O and two N atoms from two pyridine-2-carboxylate ligands and two O atoms of two water molecules. In the molecules are linked into a three-dimensional framework by O—H⋯O hydrogen bonds.
Related literature
For the design and construction of metal-organic supramolecular structures, see: Desiraju (1997); Braga et al. (1998); Mccann et al. (1996); Wai et al. (1990); Yaghi et al. (1996); Min & Lee (2002); Maira et al. (2001). For bond-length data, see: Allen et al. (1987).
Experimental
Crystal data
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Refinement
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Data collection: SMART (Siemens, 1996); cell SAINT (Siemens, 1996); 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.
Supporting information
10.1107/S1600536809005765/at2725sup1.cif
contains datablocks I, global. DOI:Structure factors: contains datablock I. DOI: 10.1107/S1600536809005765/at2725Isup2.hkl
Crystals of the title compound were synthesized using hydrothermal method in a 23 ml Teflon-lined Parr bomb, which was then sealed. Iron(II) chloride tetrahydrate (198.71 mg, 1 mmol), pyridine-2-carboxylic acid (246 mg, 2 mmol) and distilled water (10 g) were placed into the bomb and sealed. The bomb was then heated under autogenous pressure up to 433 K over the course of 7 d and allowed to cool at room temperature for 24 h. Upon opening the bomb, a clear colourless solution was decanted from small purple crystals. These crystals were washed with distilled water followed by ethanol, and allowed to air-dry at room temperature.
H1B and H2B (for two water molecules) were located in difference syntheses and refined isotropically [O—H = 0.805 (18) and 0.82 (5) Å, Uiso(H) = 0.093 (15) and 0.18 (3) Å2]. The remaining H atoms were positioned geometrically, with O—H = 0.82 Å (for H2O) and C—H = 0.93 Å for aromatic H, and constrained to ride on their parent atoms, with Uiso(H) = xUeq(C,O), where x = 1.2 for aromatic H atoms and x = 1.5 for all other H atoms.
Data collection: SMART (Siemens, 1996); cell
SAINT (Siemens, 1996); data reduction: SAINT (Siemens, 1996); 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).[Fe(C6H4NO2)2(H2O)2] | F(000) = 688 |
Mr = 336.09 | Dx = 1.475 Mg m−3 |
Monoclinic, P21/n | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2yn | Cell parameters from 2834 reflections |
a = 11.6255 (3) Å | θ = 2.4–24.8° |
b = 9.0247 (4) Å | µ = 1.02 mm−1 |
c = 14.9724 (2) Å | T = 293 K |
β = 105.568 (2)° | Plane, purple |
V = 1513.22 (8) Å3 | 0.23 × 0.19 × 0.07 mm |
Z = 4 |
Bruker SMART APEX area-detector diffractometer | 3283 independent reflections |
Radiation source: fine-focus sealed tube | 2158 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.043 |
ϕ and ω scans | θmax = 27.3°, θmin = 2.0° |
Absorption correction: multi-scan (SADABS; Sheldrick, 1996) | h = −14→14 |
Tmin = 0.796, Tmax = 0.928 | k = −11→11 |
10191 measured reflections | l = −19→18 |
Refinement on F2 | Secondary atom site location: difference Fourier map |
Least-squares matrix: full | Hydrogen site location: inferred from neighbouring sites |
R[F2 > 2σ(F2)] = 0.051 | H atoms treated by a mixture of independent and constrained refinement |
wR(F2) = 0.166 | w = 1/[σ2(Fo2) + (0.089P)2 + 0.0485P] where P = (Fo2 + 2Fc2)/3 |
S = 1.08 | (Δ/σ)max = 0.001 |
3283 reflections | Δρmax = 0.72 e Å−3 |
201 parameters | Δρmin = −0.47 e Å−3 |
6 restraints | Extinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4 |
Primary atom site location: structure-invariant direct methods | Extinction coefficient: 0.0048 (16) |
[Fe(C6H4NO2)2(H2O)2] | V = 1513.22 (8) Å3 |
Mr = 336.09 | Z = 4 |
Monoclinic, P21/n | Mo Kα radiation |
a = 11.6255 (3) Å | µ = 1.02 mm−1 |
b = 9.0247 (4) Å | T = 293 K |
c = 14.9724 (2) Å | 0.23 × 0.19 × 0.07 mm |
β = 105.568 (2)° |
Bruker SMART APEX area-detector diffractometer | 3283 independent reflections |
Absorption correction: multi-scan (SADABS; Sheldrick, 1996) | 2158 reflections with I > 2σ(I) |
Tmin = 0.796, Tmax = 0.928 | Rint = 0.043 |
10191 measured reflections |
R[F2 > 2σ(F2)] = 0.051 | 6 restraints |
wR(F2) = 0.166 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.08 | Δρmax = 0.72 e Å−3 |
3283 reflections | Δρmin = −0.47 e Å−3 |
201 parameters |
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. |
x | y | z | Uiso*/Ueq | ||
Fe1 | 0.74557 (4) | 0.85895 (5) | 0.62770 (3) | 0.0492 (2) | |
O1 | 0.8189 (2) | 0.7456 (3) | 0.75783 (16) | 0.0565 (6) | |
H1A | 0.7646 | 0.7075 | 0.7752 | 0.085* | |
O2 | 0.5913 (2) | 0.8895 (3) | 0.6788 (2) | 0.0606 (7) | |
H2A | 0.5961 | 0.8351 | 0.7235 | 0.091* | |
O3 | 0.65069 (19) | 0.9271 (3) | 0.48892 (15) | 0.0527 (6) | |
O4 | 0.5389 (2) | 0.8582 (3) | 0.35014 (17) | 0.0592 (7) | |
O5 | 0.8181 (2) | 1.0762 (3) | 0.66750 (16) | 0.0540 (6) | |
O6 | 0.9719 (3) | 1.2298 (3) | 0.6897 (2) | 0.0772 (8) | |
N1 | 0.9337 (3) | 0.8594 (3) | 0.6119 (2) | 0.0534 (7) | |
N2 | 0.6907 (2) | 0.6454 (3) | 0.54619 (18) | 0.0435 (6) | |
C1 | 0.6030 (3) | 0.8306 (4) | 0.4297 (2) | 0.0454 (7) | |
C2 | 0.6264 (3) | 0.6693 (3) | 0.4578 (2) | 0.0418 (7) | |
C3 | 0.5833 (3) | 0.5536 (4) | 0.3976 (2) | 0.0561 (9) | |
H3 | 0.5407 | 0.5724 | 0.3367 | 0.067* | |
C4 | 0.6042 (3) | 0.4112 (4) | 0.4288 (3) | 0.0587 (9) | |
H4 | 0.5742 | 0.3320 | 0.3897 | 0.070* | |
C5 | 0.6703 (3) | 0.3863 (4) | 0.5188 (3) | 0.0580 (9) | |
H5 | 0.6864 | 0.2900 | 0.5407 | 0.070* | |
C6 | 0.7123 (3) | 0.5052 (4) | 0.5758 (2) | 0.0530 (8) | |
H6 | 0.7568 | 0.4880 | 0.6365 | 0.064* | |
C7 | 0.9225 (3) | 1.1079 (4) | 0.6662 (2) | 0.0538 (8) | |
C8 | 0.9906 (3) | 0.9877 (4) | 0.6345 (2) | 0.0514 (8) | |
C9 | 1.1059 (3) | 1.0068 (5) | 0.6312 (3) | 0.0731 (11) | |
H9 | 1.1448 | 1.0967 | 0.6481 | 0.088* | |
C10 | 1.1632 (4) | 0.8908 (6) | 0.6027 (4) | 0.0974 (17) | |
H10 | 1.2406 | 0.9023 | 0.5974 | 0.117* | |
C11 | 1.1060 (4) | 0.7585 (6) | 0.5820 (4) | 0.108 (2) | |
H11 | 1.1452 | 0.6771 | 0.5659 | 0.130* | |
C12 | 0.9911 (4) | 0.7474 (5) | 0.5854 (3) | 0.0813 (13) | |
H12 | 0.9510 | 0.6583 | 0.5686 | 0.098* | |
H1B | 0.8859 (15) | 0.715 (5) | 0.778 (3) | 0.093 (15)* | |
H2B | 0.539 (5) | 0.953 (5) | 0.673 (4) | 0.18 (3)* |
U11 | U22 | U33 | U12 | U13 | U23 | |
Fe1 | 0.0490 (3) | 0.0448 (4) | 0.0474 (3) | −0.0005 (2) | 0.0020 (2) | −0.00062 (19) |
O1 | 0.0430 (12) | 0.0648 (16) | 0.0542 (14) | 0.0009 (12) | 0.0002 (10) | 0.0158 (11) |
O2 | 0.0602 (15) | 0.0518 (15) | 0.0723 (18) | 0.0102 (12) | 0.0223 (13) | 0.0148 (12) |
O3 | 0.0536 (13) | 0.0450 (14) | 0.0507 (13) | −0.0018 (10) | −0.0013 (10) | 0.0043 (10) |
O4 | 0.0566 (14) | 0.0563 (16) | 0.0512 (14) | 0.0076 (11) | −0.0091 (10) | 0.0080 (10) |
O5 | 0.0489 (13) | 0.0466 (13) | 0.0659 (15) | −0.0013 (10) | 0.0144 (10) | −0.0088 (11) |
O6 | 0.0798 (18) | 0.0646 (18) | 0.096 (2) | −0.0277 (15) | 0.0388 (15) | −0.0312 (15) |
N1 | 0.0535 (16) | 0.0470 (18) | 0.0624 (18) | −0.0004 (13) | 0.0205 (13) | −0.0032 (13) |
N2 | 0.0437 (13) | 0.0411 (15) | 0.0403 (14) | 0.0004 (11) | 0.0018 (10) | 0.0027 (10) |
C1 | 0.0345 (14) | 0.054 (2) | 0.0428 (17) | 0.0025 (13) | 0.0016 (12) | 0.0015 (14) |
C2 | 0.0361 (14) | 0.0442 (18) | 0.0418 (16) | −0.0003 (12) | 0.0045 (11) | −0.0028 (13) |
C3 | 0.0540 (19) | 0.057 (2) | 0.0473 (18) | 0.0048 (16) | −0.0028 (14) | −0.0067 (16) |
C4 | 0.059 (2) | 0.047 (2) | 0.065 (2) | 0.0017 (17) | 0.0074 (17) | −0.0142 (17) |
C5 | 0.064 (2) | 0.043 (2) | 0.070 (2) | 0.0023 (16) | 0.0226 (18) | −0.0010 (16) |
C6 | 0.0591 (18) | 0.047 (2) | 0.0489 (18) | 0.0017 (16) | 0.0080 (14) | 0.0045 (15) |
C7 | 0.059 (2) | 0.057 (2) | 0.0445 (18) | −0.0115 (16) | 0.0121 (15) | −0.0065 (15) |
C8 | 0.0509 (17) | 0.058 (2) | 0.0456 (17) | 0.0039 (16) | 0.0140 (13) | 0.0021 (15) |
C9 | 0.061 (2) | 0.075 (3) | 0.088 (3) | −0.008 (2) | 0.029 (2) | −0.001 (2) |
C10 | 0.070 (3) | 0.095 (4) | 0.143 (5) | 0.002 (3) | 0.055 (3) | 0.007 (3) |
C11 | 0.090 (3) | 0.077 (3) | 0.183 (6) | 0.013 (3) | 0.081 (4) | −0.007 (3) |
C12 | 0.076 (3) | 0.056 (3) | 0.124 (4) | 0.003 (2) | 0.047 (3) | −0.007 (2) |
Fe1—O1 | 2.163 (2) | C1—C2 | 1.520 (4) |
Fe1—O2 | 2.148 (3) | C2—C3 | 1.382 (4) |
Fe1—O3 | 2.164 (2) | C3—C4 | 1.366 (5) |
Fe1—O5 | 2.154 (2) | C3—H3 | 0.9300 |
Fe1—N1 | 2.262 (3) | C4—C5 | 1.379 (5) |
Fe1—N2 | 2.279 (2) | C4—H4 | 0.9300 |
O1—H1A | 0.8200 | C5—C6 | 1.377 (5) |
O1—H1B | 0.805 (18) | C5—H5 | 0.9300 |
O2—H2A | 0.8200 | C6—H6 | 0.9300 |
O2—H2B | 0.82 (5) | C7—C8 | 1.494 (5) |
O3—C1 | 1.260 (4) | C8—C9 | 1.365 (5) |
O4—C1 | 1.249 (4) | C9—C10 | 1.369 (6) |
O5—C7 | 1.251 (4) | C9—H9 | 0.9300 |
O6—C7 | 1.247 (4) | C10—C11 | 1.361 (7) |
N1—C12 | 1.329 (5) | C10—H10 | 0.9300 |
N1—C8 | 1.332 (4) | C11—C12 | 1.353 (6) |
N2—C6 | 1.342 (4) | C11—H11 | 0.9300 |
N2—C2 | 1.351 (4) | C12—H12 | 0.9300 |
O1—Fe1—O2 | 84.52 (10) | N2—C2—C1 | 115.8 (3) |
O1—Fe1—O3 | 167.30 (9) | C3—C2—C1 | 122.4 (3) |
O1—Fe1—O5 | 98.68 (10) | C4—C3—C2 | 119.2 (3) |
O2—Fe1—O3 | 92.66 (10) | C4—C3—H3 | 120.4 |
O2—Fe1—O5 | 95.00 (10) | C2—C3—H3 | 120.4 |
O3—Fe1—O5 | 93.89 (9) | C3—C4—C5 | 119.2 (3) |
O1—Fe1—N1 | 86.39 (10) | C3—C4—H4 | 120.4 |
O2—Fe1—N1 | 163.77 (12) | C5—C4—H4 | 120.4 |
O3—Fe1—N1 | 99.03 (10) | C6—C5—C4 | 119.4 (3) |
O5—Fe1—N1 | 73.12 (9) | C6—C5—H5 | 120.3 |
O1—Fe1—N2 | 93.92 (9) | C4—C5—H5 | 120.3 |
O2—Fe1—N2 | 99.14 (10) | N2—C6—C5 | 121.7 (3) |
O3—Fe1—N2 | 74.26 (9) | N2—C6—H6 | 119.1 |
O5—Fe1—N2 | 161.88 (9) | C5—C6—H6 | 119.1 |
N1—Fe1—N2 | 94.86 (10) | O6—C7—O5 | 124.9 (3) |
Fe1—O1—H1A | 109.5 | O6—C7—C8 | 119.1 (3) |
Fe1—O1—H1B | 128 (3) | O5—C7—C8 | 116.0 (3) |
H1A—O1—H1B | 119.0 | N1—C8—C9 | 121.7 (3) |
Fe1—O2—H2A | 109.5 | N1—C8—C7 | 116.3 (3) |
Fe1—O2—H2B | 136 (3) | C9—C8—C7 | 122.0 (3) |
H2A—O2—H2B | 112.5 | C8—C9—C10 | 118.6 (4) |
C1—O3—Fe1 | 119.6 (2) | C8—C9—H9 | 120.7 |
C7—O5—Fe1 | 120.9 (2) | C10—C9—H9 | 120.7 |
C12—N1—C8 | 118.8 (3) | C11—C10—C9 | 119.5 (4) |
C12—N1—Fe1 | 127.4 (3) | C11—C10—H10 | 120.2 |
C8—N1—Fe1 | 113.8 (2) | C9—C10—H10 | 120.2 |
C6—N2—C2 | 118.7 (3) | C12—C11—C10 | 118.9 (4) |
C6—N2—Fe1 | 128.3 (2) | C12—C11—H11 | 120.5 |
C2—N2—Fe1 | 113.04 (19) | C10—C11—H11 | 120.5 |
O4—C1—O3 | 124.8 (3) | N1—C12—C11 | 122.3 (4) |
O4—C1—C2 | 118.1 (3) | N1—C12—H12 | 118.8 |
O3—C1—C2 | 117.0 (3) | C11—C12—H12 | 118.8 |
N2—C2—C3 | 121.8 (3) |
D—H···A | D—H | H···A | D···A | D—H···A |
O1—H1B···O4i | 0.81 (2) | 1.93 (2) | 2.726 (3) | 169 (4) |
O1—H1A···O5ii | 0.82 | 1.87 | 2.661 (3) | 161 |
O2—H2B···O4iii | 0.82 (5) | 1.92 (5) | 2.704 (3) | 159 (6) |
O2—H2A···O6ii | 0.82 | 1.94 | 2.697 (4) | 153 |
Symmetry codes: (i) x+1/2, −y+3/2, z+1/2; (ii) −x+3/2, y−1/2, −z+3/2; (iii) −x+1, −y+2, −z+1. |
Experimental details
Crystal data | |
Chemical formula | [Fe(C6H4NO2)2(H2O)2] |
Mr | 336.09 |
Crystal system, space group | Monoclinic, P21/n |
Temperature (K) | 293 |
a, b, c (Å) | 11.6255 (3), 9.0247 (4), 14.9724 (2) |
β (°) | 105.568 (2) |
V (Å3) | 1513.22 (8) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 1.02 |
Crystal size (mm) | 0.23 × 0.19 × 0.07 |
Data collection | |
Diffractometer | Bruker SMART APEX area-detector diffractometer |
Absorption correction | Multi-scan (SADABS; Sheldrick, 1996) |
Tmin, Tmax | 0.796, 0.928 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 10191, 3283, 2158 |
Rint | 0.043 |
(sin θ/λ)max (Å−1) | 0.644 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.051, 0.166, 1.08 |
No. of reflections | 3283 |
No. of parameters | 201 |
No. of restraints | 6 |
H-atom treatment | H atoms treated by a mixture of independent and constrained refinement |
Δρmax, Δρmin (e Å−3) | 0.72, −0.47 |
Computer programs: SMART (Siemens, 1996), SAINT (Siemens, 1996), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).
Fe1—O1 | 2.163 (2) | Fe1—O5 | 2.154 (2) |
Fe1—O2 | 2.148 (3) | Fe1—N1 | 2.262 (3) |
Fe1—O3 | 2.164 (2) | Fe1—N2 | 2.279 (2) |
O1—Fe1—O2 | 84.52 (10) | O3—Fe1—N1 | 99.03 (10) |
O1—Fe1—O3 | 167.30 (9) | O5—Fe1—N1 | 73.12 (9) |
O1—Fe1—O5 | 98.68 (10) | O1—Fe1—N2 | 93.92 (9) |
O2—Fe1—O3 | 92.66 (10) | O2—Fe1—N2 | 99.14 (10) |
O2—Fe1—O5 | 95.00 (10) | O3—Fe1—N2 | 74.26 (9) |
O3—Fe1—O5 | 93.89 (9) | O5—Fe1—N2 | 161.88 (9) |
O1—Fe1—N1 | 86.39 (10) | N1—Fe1—N2 | 94.86 (10) |
O2—Fe1—N1 | 163.77 (12) |
D—H···A | D—H | H···A | D···A | D—H···A |
O1—H1B···O4i | 0.805 (18) | 1.93 (2) | 2.726 (3) | 169 (4) |
O1—H1A···O5ii | 0.82 | 1.87 | 2.661 (3) | 161 |
O2—H2B···O4iii | 0.82 (5) | 1.92 (5) | 2.704 (3) | 159 (6) |
O2—H2A···O6ii | 0.82 | 1.94 | 2.697 (4) | 153 |
Symmetry codes: (i) x+1/2, −y+3/2, z+1/2; (ii) −x+3/2, y−1/2, −z+3/2; (iii) −x+1, −y+2, −z+1. |
Acknowledgements
We thank the Youth Program of Jiangxi University of Finance and Economics for financial support of this work.
References
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This is an open-access article distributed under the terms of the Creative Commons Attribution (CC-BY) Licence, which permits unrestricted use, distribution, and reproduction in any medium, provided the original authors and source are cited.
In the synthesis of crystal structures by design, the assembly of molecular units in predefined arrangements is a key goal (Desiraju, 1997; Braga et al., 1998). Due to carboxyl groups are one of the most important classes of biological ligands, the coordination of metal-carboxyl groups complexes are of critical importance in biological systems, organic materials and coordination chemistry. Recently, carboxyl groups with variable coordination modes have been used to construct metal-organic supramolecular structures (Mccann et al., 1996; Wai et al., 1990; Yaghi et al., 1996; Min & Lee 2002; Maira et al., 2001). We report here in the crystal structure of the title compound, (I).
In the molecule of (I) (Fig. 1), the ligand bond lengths and angles are within normal ranges (Allen et al., 1987). In the title complex, each FeII atom is axially coordinated by water molecules and consists of an equatorial plane of two oxygen donors and two nitrogen donors from two pyridine-2-carboxylato ligands with a distorted octahedral coordination geometry. The Fe—O bonds [average 2.152 (4) Å] are somewhat shorter than the Fe—N distances [average 2.270 (8) Å].
In the crystal structure, O—H···O hydrogen bonds (Fig. 2 and Table 2) seem to be effective in the stabilization of the structure, resulting in the formation of a supramolecular network structure.