metal-organic compounds
Tris(ethylenediamine-κ2N,N′)cadmium hexafluoridogermanate
aTeachers College, College of Chemistry, Chemical Engineering and Environment, Qingdao University, Shandong 266071, People's Republic of China, bTeachers College, Qingdao University, Shandong 266071, People's Republic of China, and cCollege of Chemistry, Chemical Engineering and Environment, Qingdao University, Shandong 266071, People's Republic of China
*Correspondence e-mail: gmwang_pub@163.com
In the title compound, [Cd(C2H8N2)3](GeF6), the CdII atom, lying on a 32 symmetry site, is coordinated by six N atoms from three ethylenediamine (en) ligands in a distorted octahedral geometry. The Ge atom also lies on a 32 symmetry site and is coordinated by six F atoms. The en ligand has a twofold rotation axis passing through the mid-point of the C—C bond. The F atom is disordered over two sites with equal occupancy factors. In the crystal, the [Cd(en)3]2+ cations and [GeF6]2− anions are connected through N—H⋯F hydrogen bonds, forming a three-dimensional supramolecular network.
Related literature
For background to the structures and applications of microporous materials, see: Cheetham et al. (1999); Jiang et al. (2010); Liang et al. (2006); Yu & Xu (2003); Zou et al. (2005). For related fluorides, see: Brauer et al. (1980, 1986); Dadachov et al. (2001); Lukevics et al. (1997); Tang et al. (2001a,b,c,d,e,f); Wang et al. (2004); Wang & Wang (2011); Zhang et al. (2003). For related structures containing chiral metal complexes, see: Stalder & Wilkinson (1997); Wang et al. (2003); Yu et al. (2001).
Experimental
Crystal data
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Refinement
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Data collection: SMART (Bruker, 2007); cell SAINT (Bruker, 2007); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: DIAMOND (Brandenburg, 1999); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).
Supporting information
10.1107/S160053681200983X/hy2520sup1.cif
contains datablocks global, I. DOI:Structure factors: contains datablock I. DOI: 10.1107/S160053681200983X/hy2520Isup2.hkl
The title compound was obtained by hydrothermal methods. Typically, a mixture of GeO2 (0.104 g, 1 mmol), CdCO3 (0.174 g, 1 mmol), en (1.34 ml), pyridine (2.50 ml), hydrofluoric acid (40%, 0.20 ml) and H2O (1.00 ml) in a molar ratio of 1:1:20:31:10:56 was sealed in a 25 ml Teflon-lined steel autoclave and heated under autogenous pressure at 443 K for 7 days. The block crystals obtained were recovered by filtration, washed with distilled water and dried in air.
Atom F1 was refined as disordered over two positions, each with 50% site occupancy. All H atoms were positioned geometrically and refined as riding atoms, with C—H = 0.97 and N—H = 0.90 Å and with Uiso(H) = 1.2Ueq(C, N).
In recent years, there has been much interest in the design and synthesis of crystalline microporous materials because of their rich structural chemistry and potential applications in catalysis, ion-exchange and separation (Cheetham et al., 1999; Jiang et al., 2010; Liang et al., 2006; Yu & Xu, 2003; Zou et al., 2005). In addition to the most notable zeolites, many non-aluminosilicate-based microporous systems, such as metal phosphates, germanates, borates, etc. have been extensively investigated. In contrast, the progress in the field of fluorides has been limited, though some fluoroaluminates (Tang et al., 2001c,e), fluorosilicate (Tang et al., 2001f), fluorotitanates (Dadachov et al., 2001; Tang et al., 2001a,b,d) and fluorogermanates (Brauer et al., 1980,1986; Lukevics et al., 1997; Wang et al., 2004; Wang & Wang, 2011; Zhang et al., 2003) have been reported. The main purpose of our work is to prepare microporous germanates templated by transition-metal complexes. Unexpectedly, the title compound, (I), was obtained, which is a new fluorogermanate templated by [Cd(en)3]2+ cations (en = ethylenediamine).
The
of (I) consists of discrete [Cd(en)3]2+ cations and [GeF6]2- anions (Fig. 1). Both of the cation and anion lie on 32 symmetry sites. In the [GeF6]2- anion, the Ge atom is six-coordinated in a distorted octahedral geometry by six symmetry-related F atoms. The Ge—F bond distances are 1.812 (9) and 1.746 (9) Å, similar to the distances observed in inorganic complex K2GeF6 (Ge—F 1.77 Å) and in other fluorogermanates. In the [Cd(en)3]2+ cation, the CdII atom is bonded to six amine N aoms from three symmetry-related en ligands. The Cd—N bond distance is 2.370 (2) Å, comparable with those found in other related compounds. Interestingly, the [Cd(en)3]2+ complex generated in situ is chiral, and the enantiomers are alternately arranged along the a axis (Fig. 2). It is worthy to note that the rigid octahedrally coordinated metal amine complex with chiral features is particularly rare and usually characterized as Co and Ir complexes, such as [Co(en)3]3+, [Co(tn)3]3+ (tn = 1,3-diaminopropane), [Co(dien)2]3+ (dien = diethylenetriamine), [Ir(en)3]3+, etc (Stalder & Wilkinson, 1997; Wang et al., 2003; Yu et al., 2001). Each [Cd(en)3]2+ cation is linked to three neighboring [GeF6]2- anions through N1—H1D···F1 hydrogen bonds (Table 1), generating a hydrogen-bonded layer along [001] (Fig. 3). Adjacent layers are further connected with each other through N1—H1C···F1 hydrogen bonds (Fig. 4), giving rise to a three-dimensional supramolecular network .For background to the structures and applications of microporous materials, see: Cheetham et al. (1999); Jiang et al. (2010); Liang et al. (2006); Yu & Xu (2003); Zou et al. (2005). For related fluorides, see: Brauer et al. (1980, 1986); Dadachov et al. (2001); Lukevics et al. (1997); Tang et al. (2001a,b,c,d,e,f); Wang et al. (2004); Wang & Wang (2011); Zhang et al. (2003). For related structures containing chiral metal complexes, see: Stalder & Wilkinson (1997); Wang et al. (2003); Yu et al. (2001).
Data collection: SMART (Bruker, 2007); cell
SAINT (Bruker, 2007); data reduction: SAINT (Bruker, 2007); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: DIAMOND (Brandenburg, 1999); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).[Cd(C2H8N2)3](GeF6) | Dx = 2.019 Mg m−3 |
Mr = 479.33 | Mo Kα radiation, λ = 0.71073 Å |
Trigonal, P31c | Cell parameters from 549 reflections |
Hall symbol: -P 3 2c | θ = 4.1–26.5° |
a = 9.5422 (3) Å | µ = 3.32 mm−1 |
c = 9.9977 (5) Å | T = 293 K |
V = 788.37 (7) Å3 | Block, colorless |
Z = 2 | 0.20 × 0.18 × 0.12 mm |
F(000) = 472 |
Bruker APEX CCD diffractometer | 549 independent reflections |
Radiation source: fine-focus sealed tube | 496 reflections with I > 2σa(I) |
Graphite monochromator | Rint = 0.038 |
φ and ω scans | θmax = 26.5°, θmin = 4.1° |
Absorption correction: multi-scan (SADABS; Sheldrick, 1996) | h = −11→11 |
Tmin = 0.557, Tmax = 0.692 | k = −11→11 |
7348 measured reflections | l = −12→12 |
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)] = 0.024 | H-atom parameters constrained |
wR(F2) = 0.038 | w = 1/[σ2(Fo2) + (0.0048P)2 + 0.9629P] where P = (Fo2 + 2Fc2)/3 |
S = 1.16 | (Δ/σ)max < 0.001 |
549 reflections | Δρmax = 0.23 e Å−3 |
42 parameters | Δρmin = −0.23 e Å−3 |
12 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: 0.0045 (3) |
[Cd(C2H8N2)3](GeF6) | Z = 2 |
Mr = 479.33 | Mo Kα radiation |
Trigonal, P31c | µ = 3.32 mm−1 |
a = 9.5422 (3) Å | T = 293 K |
c = 9.9977 (5) Å | 0.20 × 0.18 × 0.12 mm |
V = 788.37 (7) Å3 |
Bruker APEX CCD diffractometer | 549 independent reflections |
Absorption correction: multi-scan (SADABS; Sheldrick, 1996) | 496 reflections with I > 2σa(I) |
Tmin = 0.557, Tmax = 0.692 | Rint = 0.038 |
7348 measured reflections |
R[F2 > 2σ(F2)] = 0.024 | 12 restraints |
wR(F2) = 0.038 | H-atom parameters constrained |
S = 1.16 | Δρmax = 0.23 e Å−3 |
549 reflections | Δρmin = −0.23 e Å−3 |
42 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 | Occ. (<1) | |
Cd1 | 0.3333 | 0.6667 | 0.2500 | 0.03249 (17) | |
Ge1 | 0.6667 | 0.3333 | 0.2500 | 0.02960 (19) | |
N1 | 0.2829 (3) | 0.4387 (3) | 0.1196 (2) | 0.0444 (6) | |
H1C | 0.2637 | 0.4538 | 0.0341 | 0.053* | |
H1D | 0.3698 | 0.4254 | 0.1212 | 0.053* | |
C1 | 0.1425 (4) | 0.2956 (4) | 0.1743 (3) | 0.0504 (8) | |
H1A | 0.1381 | 0.1989 | 0.1388 | 0.060* | |
H1B | 0.0443 | 0.2949 | 0.1479 | 0.060* | |
F1 | 0.5391 (11) | 0.3708 (8) | 0.1387 (10) | 0.065 (2) | 0.50 |
F1' | 0.5004 (11) | 0.2974 (8) | 0.1521 (10) | 0.064 (2) | 0.50 |
U11 | U22 | U33 | U12 | U13 | U23 | |
Cd1 | 0.0326 (2) | 0.0326 (2) | 0.0323 (3) | 0.01630 (10) | 0.000 | 0.000 |
Ge1 | 0.0312 (3) | 0.0312 (3) | 0.0264 (4) | 0.01559 (13) | 0.000 | 0.000 |
N1 | 0.0559 (17) | 0.0475 (16) | 0.0364 (13) | 0.0309 (14) | −0.0008 (12) | −0.0037 (12) |
C1 | 0.056 (2) | 0.0397 (18) | 0.0518 (18) | 0.0214 (16) | −0.0092 (16) | −0.0112 (14) |
F1 | 0.074 (5) | 0.092 (5) | 0.051 (3) | 0.058 (4) | −0.012 (3) | 0.001 (4) |
F1' | 0.049 (4) | 0.098 (5) | 0.049 (3) | 0.040 (4) | −0.021 (3) | −0.010 (4) |
Cd1—N1i | 2.370 (2) | Ge1—F1vi | 1.812 (9) |
Cd1—N1ii | 2.370 (2) | Ge1—F1viii | 1.812 (9) |
Cd1—N1iii | 2.370 (2) | Ge1—F1ix | 1.812 (9) |
Cd1—N1 | 2.370 (2) | Ge1—F1v | 1.812 (9) |
Cd1—N1iv | 2.370 (2) | Ge1—F1 | 1.812 (9) |
Cd1—N1v | 2.370 (2) | N1—C1 | 1.459 (4) |
Ge1—F1'vi | 1.746 (9) | N1—H1C | 0.9000 |
Ge1—F1'vii | 1.746 (9) | N1—H1D | 0.9000 |
Ge1—F1'viii | 1.746 (9) | C1—C1iii | 1.518 (6) |
Ge1—F1'v | 1.746 (9) | C1—H1A | 0.9700 |
Ge1—F1'ix | 1.746 (9) | C1—H1B | 0.9700 |
Ge1—F1' | 1.746 (9) | F1—F1' | 0.621 (10) |
Ge1—F1vii | 1.812 (9) | ||
N1i—Cd1—N1ii | 74.72 (12) | F1'ix—Ge1—F1viii | 176.1 (7) |
N1i—Cd1—N1iii | 92.62 (8) | F1'—Ge1—F1viii | 91.4 (3) |
N1ii—Cd1—N1iii | 103.54 (12) | F1vii—Ge1—F1viii | 86.2 (5) |
N1i—Cd1—N1 | 159.72 (12) | F1vi—Ge1—F1viii | 82.4 (6) |
N1ii—Cd1—N1 | 92.62 (8) | F1'vi—Ge1—F1ix | 73.7 (3) |
N1iii—Cd1—N1 | 74.72 (12) | F1'vii—Ge1—F1ix | 90.6 (2) |
N1i—Cd1—N1iv | 103.54 (12) | F1'viii—Ge1—F1ix | 176.1 (7) |
N1ii—Cd1—N1iv | 92.62 (8) | F1'v—Ge1—F1ix | 91.4 (3) |
N1iii—Cd1—N1iv | 159.72 (12) | F1'—Ge1—F1ix | 100.8 (2) |
N1—Cd1—N1iv | 92.62 (8) | F1vii—Ge1—F1ix | 82.4 (6) |
N1i—Cd1—N1v | 92.62 (8) | F1vi—Ge1—F1ix | 86.2 (5) |
N1ii—Cd1—N1v | 159.72 (12) | F1viii—Ge1—F1ix | 160.3 (5) |
N1iii—Cd1—N1v | 92.62 (8) | F1'vi—Ge1—F1v | 176.1 (7) |
N1—Cd1—N1v | 103.54 (12) | F1'vii—Ge1—F1v | 100.8 (2) |
N1iv—Cd1—N1v | 74.72 (12) | F1'viii—Ge1—F1v | 73.7 (3) |
F1'vi—Ge1—F1'vii | 76.2 (6) | F1'ix—Ge1—F1v | 91.4 (3) |
F1'vi—Ge1—F1'viii | 103.8 (6) | F1'—Ge1—F1v | 90.6 (2) |
F1'vii—Ge1—F1'viii | 91.7 (5) | F1vii—Ge1—F1v | 86.2 (5) |
F1'vi—Ge1—F1'v | 160.4 (5) | F1vi—Ge1—F1v | 160.3 (5) |
F1'vii—Ge1—F1'v | 91.7 (5) | F1viii—Ge1—F1v | 86.2 (5) |
F1'viii—Ge1—F1'v | 91.7 (5) | F1ix—Ge1—F1v | 108.8 (5) |
F1'vi—Ge1—F1'ix | 91.7 (5) | F1'vi—Ge1—F1 | 100.8 (2) |
F1'vii—Ge1—F1'ix | 103.8 (6) | F1'vii—Ge1—F1 | 176.1 (7) |
F1'viii—Ge1—F1'ix | 160.4 (5) | F1'viii—Ge1—F1 | 91.4 (3) |
F1'v—Ge1—F1'ix | 76.2 (6) | F1'v—Ge1—F1 | 90.6 (2) |
F1'vi—Ge1—F1' | 91.7 (5) | F1'ix—Ge1—F1 | 73.7 (3) |
F1'vii—Ge1—F1' | 160.4 (5) | F1vii—Ge1—F1 | 160.3 (5) |
F1'viii—Ge1—F1' | 76.2 (6) | F1vi—Ge1—F1 | 86.2 (5) |
F1'v—Ge1—F1' | 103.8 (6) | F1viii—Ge1—F1 | 108.8 (5) |
F1'ix—Ge1—F1' | 91.7 (5) | F1ix—Ge1—F1 | 86.2 (5) |
F1'vi—Ge1—F1vii | 91.4 (3) | F1v—Ge1—F1 | 82.4 (6) |
F1'viii—Ge1—F1vii | 100.8 (2) | C1—N1—Cd1 | 108.83 (17) |
F1'v—Ge1—F1vii | 73.7 (3) | C1—N1—H1C | 109.9 |
F1'ix—Ge1—F1vii | 90.6 (2) | Cd1—N1—H1C | 109.9 |
F1'—Ge1—F1vii | 176.1 (7) | C1—N1—H1D | 109.9 |
F1'vii—Ge1—F1vi | 91.4 (3) | Cd1—N1—H1D | 109.9 |
F1'viii—Ge1—F1vi | 90.6 (2) | H1C—N1—H1D | 108.3 |
F1'v—Ge1—F1vi | 176.1 (7) | N1—C1—C1iii | 110.1 (2) |
F1'ix—Ge1—F1vi | 100.8 (2) | N1—C1—H1A | 109.6 |
F1'—Ge1—F1vi | 73.7 (3) | C1iii—C1—H1A | 109.6 |
F1vii—Ge1—F1vi | 108.8 (5) | N1—C1—H1B | 109.6 |
F1'vi—Ge1—F1viii | 90.6 (2) | C1iii—C1—H1B | 109.6 |
F1'vii—Ge1—F1viii | 73.7 (3) | H1A—C1—H1B | 108.2 |
F1'v—Ge1—F1viii | 100.8 (2) |
Symmetry codes: (i) x, x−y+1, −z+1/2; (ii) −x+y, −x+1, z; (iii) −x+y, y, −z+1/2; (iv) −y+1, x−y+1, z; (v) −y+1, −x+1, −z+1/2; (vi) −y+1, x−y, z; (vii) −x+y+1, y, −z+1/2; (viii) x, x−y, −z+1/2; (ix) −x+y+1, −x+1, z. |
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H1C···F1x | 0.90 | 2.28 | 3.135 (11) | 158 |
N1—H1C···F1′x | 0.90 | 2.06 | 2.959 (11) | 173 |
N1—H1D···F1 | 0.90 | 1.94 | 2.831 (11) | 172 |
N1—H1D···F1′ | 0.90 | 2.16 | 3.005 (11) | 156 |
Symmetry code: (x) x−y, x, −z. |
Experimental details
Crystal data | |
Chemical formula | [Cd(C2H8N2)3](GeF6) |
Mr | 479.33 |
Crystal system, space group | Trigonal, P31c |
Temperature (K) | 293 |
a, c (Å) | 9.5422 (3), 9.9977 (5) |
V (Å3) | 788.37 (7) |
Z | 2 |
Radiation type | Mo Kα |
µ (mm−1) | 3.32 |
Crystal size (mm) | 0.20 × 0.18 × 0.12 |
Data collection | |
Diffractometer | Bruker APEX CCD |
Absorption correction | Multi-scan (SADABS; Sheldrick, 1996) |
Tmin, Tmax | 0.557, 0.692 |
No. of measured, independent and observed [I > 2σa(I)] reflections | 7348, 549, 496 |
Rint | 0.038 |
(sin θ/λ)max (Å−1) | 0.627 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.024, 0.038, 1.16 |
No. of reflections | 549 |
No. of parameters | 42 |
No. of restraints | 12 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.23, −0.23 |
Computer programs: SMART (Bruker, 2007), SAINT (Bruker, 2007), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), DIAMOND (Brandenburg, 1999), SHELXTL (Sheldrick, 2008).
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H1C···F1i | 0.90 | 2.28 | 3.135 (11) | 158 |
N1—H1C···F1'i | 0.90 | 2.06 | 2.959 (11) | 173 |
N1—H1D···F1 | 0.90 | 1.94 | 2.831 (11) | 172 |
N1—H1D···F1' | 0.90 | 2.16 | 3.005 (11) | 156 |
Symmetry code: (i) x−y, x, −z. |
Acknowledgements
This work was supported by the National Natural Science Foundation of China (No. 20901043), the Young Scientist Foundation of Shandong Province (No. BS2009CL041) and the Qingdao University Research Fund (No. 063–06300522).
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In recent years, there has been much interest in the design and synthesis of crystalline microporous materials because of their rich structural chemistry and potential applications in catalysis, ion-exchange and separation (Cheetham et al., 1999; Jiang et al., 2010; Liang et al., 2006; Yu & Xu, 2003; Zou et al., 2005). In addition to the most notable zeolites, many non-aluminosilicate-based microporous systems, such as metal phosphates, germanates, borates, etc. have been extensively investigated. In contrast, the progress in the field of fluorides has been limited, though some fluoroaluminates (Tang et al., 2001c,e), fluorosilicate (Tang et al., 2001f), fluorotitanates (Dadachov et al., 2001; Tang et al., 2001a,b,d) and fluorogermanates (Brauer et al., 1980,1986; Lukevics et al., 1997; Wang et al., 2004; Wang & Wang, 2011; Zhang et al., 2003) have been reported. The main purpose of our work is to prepare microporous germanates templated by transition-metal complexes. Unexpectedly, the title compound, (I), was obtained, which is a new fluorogermanate templated by [Cd(en)3]2+ cations (en = ethylenediamine).
The crystal structure of (I) consists of discrete [Cd(en)3]2+ cations and [GeF6]2- anions (Fig. 1). Both of the cation and anion lie on 32 symmetry sites. In the [GeF6]2- anion, the Ge atom is six-coordinated in a distorted octahedral geometry by six symmetry-related F atoms. The Ge—F bond distances are 1.812 (9) and 1.746 (9) Å, similar to the distances observed in inorganic complex K2GeF6 (Ge—F 1.77 Å) and in other fluorogermanates. In the [Cd(en)3]2+ cation, the CdII atom is bonded to six amine N aoms from three symmetry-related en ligands. The Cd—N bond distance is 2.370 (2) Å, comparable with those found in other related compounds. Interestingly, the [Cd(en)3]2+ complex generated in situ is chiral, and the enantiomers are alternately arranged along the a axis (Fig. 2). It is worthy to note that the rigid octahedrally coordinated metal amine complex with chiral features is particularly rare and usually characterized as Co and Ir complexes, such as [Co(en)3]3+, [Co(tn)3]3+ (tn = 1,3-diaminopropane), [Co(dien)2]3+ (dien = diethylenetriamine), [Ir(en)3]3+, etc (Stalder & Wilkinson, 1997; Wang et al., 2003; Yu et al., 2001). Each [Cd(en)3]2+ cation is linked to three neighboring [GeF6]2- anions through N1—H1D···F1 hydrogen bonds (Table 1), generating a hydrogen-bonded layer along [001] (Fig. 3). Adjacent layers are further connected with each other through N1—H1C···F1 hydrogen bonds (Fig. 4), giving rise to a three-dimensional supramolecular network .