organic compounds
(±)-Bis(1-carboxy-2-phenylethanaminium) hexafluorosilicate(VI)
aUnité de Recherche de Chimie de l'Environnement et Moléculaire Structurale (CHEMS), Université Mentouri-Constantine, 25000 Algeria, bLaboratoire de Chimie de Coordination, UPR CNRS 8241, 205 route de Narbonne, 31077 Toulouse Cedex, France, and cCentre de Difractométrie X, UMR 6226 CNRS Unité Sciences Chimiques de Rennes, Université de Rennes I, 263 Avenue du Général Leclerc, 35042 Rennes, France
*Correspondence e-mail: bouacida_sofiane@yahoo.fr
The 9H12NO2+·SiF62−, consists of a phenylalaninium cation and half of a fluorosilicate anion, the Si atom being located on an inversion center. In the crystal, all of the F atoms act as hydrogen-bond acceptors and link the cations through different graph-set motifs, forming layers developing parallel to (100).
of the title fluorosilicate salt, 2CRelated literature
For applications of fluorosilicate salts, see: Katayama et al. (2001); Kalem (2004); Airoldi & De Farias (2000); Han et al. (2000); Gelmboldt (1989); Gelmboldt et al. (2007). For our previous work on hydrogen-bonding interactions in the crystal structures of protonated see: Bouacida et al. (2005, 2007, 2009); Benslimane et al. (2007); Bouacida (2008). For a description of the Cambridge Structural Database, see: Allen (2002). For hydrogen-bond motifs, see: Etter et al. (1990); Bernstein et al. (1995); Janiak (2000).
Experimental
Crystal data
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Data collection
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Refinement
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Data collection: COLLECT (Otwinowski & Minor, 1997); cell DIRAX/LSQ (Duisenberg et al., 2003); data reduction: EVALCCD (Duisenberg et al., 2003); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEPIII (Burnett & Johnson, 1996), ORTEP-3 for Windows (Farrugia, 1997) and PLATON (Spek, 2009); software used to prepare material for publication: WinGX (Farrugia, 1999).
Supporting information
10.1107/S1600536812021587/ez2295sup1.cif
contains datablocks global, I. DOI:Structure factors: contains datablock I. DOI: 10.1107/S1600536812021587/ez2295Isup2.hkl
Crystals of compound I were grown from an aqueous solution that was obtained by dissolving 1 mmol SiO2 and 2 mmol phenylalanine in hydrofluoric acid (HF). The solutions were slowly evaporated to dryness for a couple of weeks. Some white crystals were carefully isolated under polarizing microscope for analysis by X-ray diffraction.
All non-H atoms were refined with anisotropic atomic displacement parameters. All H atoms were localized on Fourier maps but introduced in calculated positions and treated as riding on their parent C, N and O atoms, with C—H = 0.93,0.97, 0.98 Å, N—H = 0.89 Å and O—H = 0.82 Å with Uiso(H) = 1.2 or 1.5 Ueq(C, N or O).
Data collection: COLLECT (Otwinowski & Minor, 1997); cell
DIRAX/LSQ (Duisenberg et al., 2003); data reduction: EVALCCD (Duisenberg et al., 2003); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEPIII (Burnett & Johnson, 1996), ORTEP-3 for Windows (Farrugia, 1997) and PLATON (Spek, 2009); software used to prepare material for publication: WinGX (Farrugia, 1999).2C9H12NO2+·SiF62− | F(000) = 492 |
Mr = 474.48 | Dx = 1.496 Mg m−3 |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2ybc | Cell parameters from 4769 reflections |
a = 11.183 (2) Å | θ = 5.0–27.5° |
b = 5.7531 (10) Å | µ = 0.19 mm−1 |
c = 17.000 (4) Å | T = 295 K |
β = 105.59 (2)° | Block, white |
V = 1053.5 (4) Å3 | 0.59 × 0.50 × 0.37 mm |
Z = 2 |
Nonius KappaCCD diffractometer | 1917 reflections with I > 2σ(I) |
Radiation source: fine-focus sealed tube | Rint = 0.000 |
Graphite monochromator | θmax = 27.5°, θmin = 5.0° |
Detector resolution: 9 pixels mm-1 | h = −14→13 |
CCD rotation images, thick slices scans | k = 0→7 |
2412 measured reflections | l = 0→22 |
2412 independent reflections |
Refinement on F2 | Primary atom site location: structure-invariant direct methods |
Least-squares matrix: full | Secondary atom site location: difference Fourier map |
R[F2 > 2σ(F2)] = 0.035 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.086 | H-atom parameters constrained |
S = 1.03 | w = 1/[σ2(Fo2) + (0.0329P)2 + 0.2833P] where P = (Fo2 + 2Fc2)/3 |
2412 reflections | (Δ/σ)max = 0.001 |
144 parameters | Δρmax = 0.22 e Å−3 |
0 restraints | Δρmin = −0.19 e Å−3 |
2C9H12NO2+·SiF62− | V = 1053.5 (4) Å3 |
Mr = 474.48 | Z = 2 |
Monoclinic, P21/c | Mo Kα radiation |
a = 11.183 (2) Å | µ = 0.19 mm−1 |
b = 5.7531 (10) Å | T = 295 K |
c = 17.000 (4) Å | 0.59 × 0.50 × 0.37 mm |
β = 105.59 (2)° |
Nonius KappaCCD diffractometer | 1917 reflections with I > 2σ(I) |
2412 measured reflections | Rint = 0.000 |
2412 independent reflections |
R[F2 > 2σ(F2)] = 0.035 | 0 restraints |
wR(F2) = 0.086 | H-atom parameters constrained |
S = 1.03 | Δρmax = 0.22 e Å−3 |
2412 reflections | Δρmin = −0.19 e Å−3 |
144 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 | ||
Si1 | 0.0000 | 0.5000 | 0.5000 | 0.02345 (13) | |
F1 | 0.07812 (8) | 0.54094 (14) | 0.43002 (5) | 0.0345 (2) | |
F2 | −0.11419 (8) | 0.36774 (15) | 0.42781 (5) | 0.0371 (2) | |
F3 | 0.07100 (8) | 0.24091 (13) | 0.52540 (5) | 0.0346 (2) | |
O1 | 0.17794 (11) | 0.0905 (2) | 0.21347 (6) | 0.0403 (3) | |
H1 | 0.1700 | 0.0176 | 0.1709 | 0.060* | |
O2 | 0.10064 (12) | −0.23340 (19) | 0.25348 (6) | 0.0431 (3) | |
N2 | 0.05617 (12) | 0.0158 (2) | 0.37935 (7) | 0.0307 (3) | |
H2A | −0.0126 | 0.0728 | 0.3455 | 0.046* | |
H2B | 0.0661 | 0.0763 | 0.4289 | 0.046* | |
H2C | 0.0499 | −0.1381 | 0.3820 | 0.046* | |
C2 | 0.16410 (14) | 0.0759 (2) | 0.34897 (8) | 0.0293 (3) | |
H2 | 0.1696 | 0.2449 | 0.3435 | 0.035* | |
C1 | 0.14352 (13) | −0.0392 (2) | 0.26636 (8) | 0.0289 (3) | |
C3 | 0.28085 (15) | −0.0161 (3) | 0.41120 (9) | 0.0410 (4) | |
H3A | 0.2872 | 0.0580 | 0.4634 | 0.049* | |
H3B | 0.2708 | −0.1816 | 0.4182 | 0.049* | |
C4 | 0.40009 (15) | 0.0225 (3) | 0.38861 (9) | 0.0374 (4) | |
C6 | 0.55760 (19) | −0.1169 (4) | 0.32857 (12) | 0.0563 (5) | |
H6 | 0.5865 | −0.2308 | 0.2994 | 0.068* | |
C9 | 0.47022 (18) | 0.2226 (3) | 0.41237 (11) | 0.0493 (4) | |
H9 | 0.4405 | 0.3395 | 0.4399 | 0.059* | |
C8 | 0.58322 (19) | 0.2497 (4) | 0.39562 (12) | 0.0585 (5) | |
H8 | 0.6297 | 0.3835 | 0.4124 | 0.070* | |
C5 | 0.44501 (17) | −0.1453 (3) | 0.34602 (11) | 0.0469 (4) | |
H5 | 0.3988 | −0.2791 | 0.3289 | 0.056* | |
C7 | 0.62729 (18) | 0.0799 (4) | 0.35423 (12) | 0.0580 (5) | |
H7 | 0.7041 | 0.0975 | 0.3435 | 0.070* |
U11 | U22 | U33 | U12 | U13 | U23 | |
Si1 | 0.0314 (3) | 0.0221 (2) | 0.0178 (2) | −0.0039 (2) | 0.00823 (19) | −0.00049 (18) |
F1 | 0.0451 (5) | 0.0334 (4) | 0.0310 (4) | −0.0022 (4) | 0.0206 (4) | 0.0025 (3) |
F2 | 0.0414 (5) | 0.0393 (5) | 0.0281 (4) | −0.0112 (4) | 0.0049 (4) | −0.0044 (3) |
F3 | 0.0472 (5) | 0.0277 (4) | 0.0311 (4) | 0.0050 (4) | 0.0141 (4) | 0.0041 (3) |
O1 | 0.0516 (7) | 0.0483 (6) | 0.0232 (5) | −0.0117 (5) | 0.0137 (5) | −0.0002 (4) |
O2 | 0.0606 (8) | 0.0396 (6) | 0.0310 (5) | −0.0123 (5) | 0.0156 (5) | −0.0066 (5) |
N2 | 0.0388 (7) | 0.0284 (6) | 0.0283 (6) | 0.0025 (5) | 0.0147 (5) | 0.0024 (5) |
C2 | 0.0359 (8) | 0.0285 (7) | 0.0252 (6) | −0.0043 (6) | 0.0110 (6) | −0.0002 (5) |
C1 | 0.0274 (7) | 0.0352 (8) | 0.0238 (6) | 0.0002 (6) | 0.0065 (5) | 0.0010 (5) |
C3 | 0.0388 (9) | 0.0543 (10) | 0.0265 (7) | −0.0026 (7) | 0.0031 (6) | 0.0038 (7) |
C4 | 0.0324 (8) | 0.0468 (9) | 0.0280 (7) | −0.0026 (7) | −0.0003 (6) | 0.0029 (6) |
C6 | 0.0453 (11) | 0.0653 (12) | 0.0589 (11) | 0.0071 (9) | 0.0150 (9) | −0.0007 (9) |
C9 | 0.0484 (11) | 0.0497 (10) | 0.0441 (9) | −0.0052 (8) | 0.0027 (8) | −0.0041 (8) |
C8 | 0.0491 (12) | 0.0588 (12) | 0.0586 (11) | −0.0176 (10) | −0.0009 (9) | 0.0077 (10) |
C5 | 0.0412 (10) | 0.0472 (10) | 0.0502 (10) | −0.0055 (8) | 0.0088 (8) | −0.0044 (7) |
C7 | 0.0349 (10) | 0.0765 (14) | 0.0596 (11) | −0.0056 (10) | 0.0071 (9) | 0.0138 (10) |
Si1—F1i | 1.6711 (9) | C2—H2 | 0.9800 |
Si1—F1 | 1.6711 (9) | C3—C4 | 1.500 (2) |
Si1—F3i | 1.6895 (8) | C3—H3A | 0.9700 |
Si1—F3 | 1.6895 (8) | C3—H3B | 0.9700 |
Si1—F2 | 1.6952 (8) | C4—C5 | 1.380 (3) |
Si1—F2i | 1.6952 (9) | C4—C9 | 1.391 (2) |
O1—C1 | 1.3036 (17) | C6—C7 | 1.377 (3) |
O1—H1 | 0.8200 | C6—C5 | 1.379 (3) |
O2—C1 | 1.2121 (17) | C6—H6 | 0.9300 |
N2—C2 | 1.4760 (18) | C9—C8 | 1.377 (3) |
N2—H2A | 0.8900 | C9—H9 | 0.9300 |
N2—H2B | 0.8900 | C8—C7 | 1.371 (3) |
N2—H2C | 0.8900 | C8—H8 | 0.9300 |
C2—C1 | 1.5135 (19) | C5—H5 | 0.9300 |
C2—C3 | 1.537 (2) | C7—H7 | 0.9300 |
F1i—Si1—F1 | 180.0 | O2—C1—O1 | 125.37 (13) |
F1i—Si1—F3i | 90.38 (4) | O2—C1—C2 | 121.67 (13) |
F1—Si1—F3i | 89.62 (4) | O1—C1—C2 | 112.95 (12) |
F1i—Si1—F3 | 89.62 (4) | C4—C3—C2 | 114.97 (12) |
F1—Si1—F3 | 90.38 (4) | C4—C3—H3A | 108.5 |
F3i—Si1—F3 | 180.0 | C2—C3—H3A | 108.5 |
F1i—Si1—F2 | 90.90 (5) | C4—C3—H3B | 108.5 |
F1—Si1—F2 | 89.10 (4) | C2—C3—H3B | 108.5 |
F3i—Si1—F2 | 90.00 (4) | H3A—C3—H3B | 107.5 |
F3—Si1—F2 | 90.00 (4) | C5—C4—C9 | 118.37 (17) |
F1i—Si1—F2i | 89.10 (4) | C5—C4—C3 | 120.33 (15) |
F1—Si1—F2i | 90.90 (5) | C9—C4—C3 | 121.26 (16) |
F3i—Si1—F2i | 90.00 (4) | C7—C6—C5 | 120.05 (19) |
F3—Si1—F2i | 90.00 (4) | C7—C6—H6 | 120.0 |
F2—Si1—F2i | 180.0 | C5—C6—H6 | 120.0 |
C1—O1—H1 | 109.5 | C8—C9—C4 | 120.73 (18) |
C2—N2—H2A | 109.5 | C8—C9—H9 | 119.6 |
C2—N2—H2B | 109.5 | C4—C9—H9 | 119.6 |
H2A—N2—H2B | 109.5 | C7—C8—C9 | 120.13 (18) |
C2—N2—H2C | 109.5 | C7—C8—H8 | 119.9 |
H2A—N2—H2C | 109.5 | C9—C8—H8 | 119.9 |
H2B—N2—H2C | 109.5 | C6—C5—C4 | 120.84 (17) |
N2—C2—C1 | 106.69 (11) | C6—C5—H5 | 119.6 |
N2—C2—C3 | 107.57 (11) | C4—C5—H5 | 119.6 |
C1—C2—C3 | 112.16 (13) | C8—C7—C6 | 119.84 (19) |
N2—C2—H2 | 110.1 | C8—C7—H7 | 120.1 |
C1—C2—H2 | 110.1 | C6—C7—H7 | 120.1 |
C3—C2—H2 | 110.1 | ||
N2—C2—C1—O2 | −39.96 (18) | C4—C9—C8—C7 | 0.8 (3) |
C3—C2—C1—O2 | 77.58 (18) | C7—C6—C5—C4 | 0.5 (3) |
N2—C2—C1—O1 | 140.88 (13) | C9—C4—C5—C6 | 1.0 (2) |
C3—C2—C1—O1 | −101.58 (15) | C3—C4—C5—C6 | −176.65 (15) |
N2—C2—C3—C4 | 177.95 (13) | C9—C8—C7—C6 | 0.8 (3) |
C1—C2—C3—C4 | 60.93 (18) | C5—C6—C7—C8 | −1.4 (3) |
C2—C3—C4—C5 | −92.09 (19) | C4—C3—C2—C1 | 60.93 (18) |
C2—C3—C4—C9 | 90.30 (18) | C4—C3—C2—N2 | 177.95 (13) |
C5—C4—C9—C8 | −1.7 (2) | C3—C2—C1—O1 | −101.58 (15) |
C3—C4—C9—C8 | 175.98 (15) | C3—C2—C1—O2 | 77.58 (18) |
Symmetry code: (i) −x, −y+1, −z+1. |
D—H···A | D—H | H···A | D···A | D—H···A |
O1—H1···F2ii | 0.82 | 1.84 | 2.6456 (14) | 167 |
N2—H2A···O2iii | 0.89 | 2.04 | 2.8511 (17) | 151 |
N2—H2B···F3 | 0.89 | 1.88 | 2.7656 (15) | 171 |
N2—H2C···F1iv | 0.89 | 2.01 | 2.8549 (15) | 158 |
Symmetry codes: (ii) −x, y−1/2, −z+1/2; (iii) −x, y+1/2, −z+1/2; (iv) x, y−1, z. |
Experimental details
Crystal data | |
Chemical formula | 2C9H12NO2+·SiF62− |
Mr | 474.48 |
Crystal system, space group | Monoclinic, P21/c |
Temperature (K) | 295 |
a, b, c (Å) | 11.183 (2), 5.7531 (10), 17.000 (4) |
β (°) | 105.59 (2) |
V (Å3) | 1053.5 (4) |
Z | 2 |
Radiation type | Mo Kα |
µ (mm−1) | 0.19 |
Crystal size (mm) | 0.59 × 0.50 × 0.37 |
Data collection | |
Diffractometer | Nonius KappaCCD diffractometer |
Absorption correction | – |
No. of measured, independent and observed [I > 2σ(I)] reflections | 2412, 2412, 1917 |
Rint | 0.000 |
(sin θ/λ)max (Å−1) | 0.651 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.035, 0.086, 1.03 |
No. of reflections | 2412 |
No. of parameters | 144 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.22, −0.19 |
Computer programs: COLLECT (Otwinowski & Minor, 1997), DIRAX/LSQ (Duisenberg et al., 2003), EVALCCD (Duisenberg et al., 2003), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEPIII (Burnett & Johnson, 1996), ORTEP-3 for Windows (Farrugia, 1997) and PLATON (Spek, 2009), WinGX (Farrugia, 1999).
D—H···A | D—H | H···A | D···A | D—H···A |
O1—H1···F2i | 0.82 | 1.84 | 2.6456 (14) | 166.9 |
N2—H2A···O2ii | 0.89 | 2.04 | 2.8511 (17) | 151.3 |
N2—H2B···F3 | 0.89 | 1.88 | 2.7656 (15) | 171.3 |
N2—H2C···F1iii | 0.89 | 2.01 | 2.8549 (15) | 158.2 |
Symmetry codes: (i) −x, y−1/2, −z+1/2; (ii) −x, y+1/2, −z+1/2; (iii) x, y−1, z. |
Acknowledgements
Thanks are due to MESRS and ANDRU (Ministére de l'Enseignement Supérieur et de la Recherche Scientifique et l'Agence Nationale pour le Développement de la Recherche Universitaire - Algérie) for financial support via the PNR programme.
References
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Fluorosilicate salts involving onium cations of N– and O– containing organic bases and amino acids have practical applications as ionic liquids (Katayama et al., 2001), dielectrics with cryptocrystalline structure (Kalem, 2004), layered organic-inorganic hybrid materials (Airoldi & De Farias, 2000) and chemical reagents (Han et al., 2000; Gelmboldt, 1989). Their structures are commonly dominated by strong directional interactions involving F atoms and convenient hydrogen-bond donors, although the relationships in such systems can be complicated due to the presence of competitive OH and NH binding sites (Gelmboldt et al., 2007). We report here the synthesis, crystal structure and hydrogen-bonded frameworks of a new hybrid compound based on fluorosilicate. The title compound (I) was prepared as part of our ongoing studies of hydrogen-bonding interactions in the crystal structures of protonated amines (Bouacida et al., 2005, 2007, 2009; Benslimane et al., 2007; Bouacida, 2008). From the molecular point of view, the structure is quite simple, since the individual components do not deviate from the expected geometries, with bond distances and angles lying within reported values for these species (CSD, Allen, 2002). The most attractive aspect of these structures resides in their extensive hydrogen-bonding schemes.
The asymmetric unit of (I) is built up from a (+/-)-phenylalaninium cation and half a molecule of a hexafluorosilicate anion located on an inversion center, connected by N—H···F hydrogen bonds (Fig. 1).
As observed in compound I, all the F atoms of the hexafluorosilicate anion act as hydrogen bond acceptors and are engaged in N—H···F and O—H···F bonds with the alaninium part of the cation (Fig. 2, Table 1). Two H atoms, H2B and H2C and their symmetry related counterparts (-x, -y, 1 - z), of the ammonium NH3 interact with two symmetry related fluorosilicate (-x, -y, 1 - z) building a R42(8) ring labelled B1, whereas H2A, the third H atom of the NH3 and the H atom of the symmetry related (-x, y + 1/2, -z + 1/2) carboxylate complete a R33(10) graph set motif labelled B2. Futhermore, two symmetry related (-x, y - 1/2, 1/2 - z) cations and one fluorosilicate (x, y - 1, z) form a R33 (14) ring labelled B3, through N2—H2C···F1, N2—H2B···O2 and O1—H···F2 (Etter et al., 1990; Bernstein et al., 1995), see Table 1, Fig. 2.
These hydrogen bonds result in the formation of layers parallel to the (1 0 0) plane. In these layers, chains of cations and anions alternate (Fig. 3). As shown in the Figure, the phenyl rings of the symmetry related layers are intercalated; however the centroid to centroid distance between the phenyl rings are too long (4.958 (1) and 4.523 (1) Å) to consider π-π interactions (Janiak, 2000).