organic compounds
Bis(4-sulfamoylanilinium) sulfate
aDepartment of Physics, Devanga Arts College, Aruppukottai 626 101, India, and bDepartment of Physics, University College of Engineering Nagercoil, Anna University Chennai, Nagercoil 629 004, India
*Correspondence e-mail: athi81s@yahoo.co.in
In the title salt, 2C6H9N2O2S+·SO42−, the sulfate S atom is situated on a crystallographic twofold axis (the symmetry of the anion is 2). The anion exerts intense libration, which is manifested by shortening of the observed sulfate S—O bonds, as well as by features in the electron-density map. The is stabilized through a three-dimensional hydrogen-bonding network formed by strong N—H⋯O hydrogen bonds.
Related literature
For information about folate synthesis, see: Kent (2000). For related structures, see: Pandiarajan et al. (2011); Zaouali Zgolli et al. (2010). For correction of the S—O distances in the sulfate anion due to libration movement, see: Nardelli (1995). For TLS approximation, see: Schomaker & Trueblood (1968). For graph-set motifs, see: Etter et al. (1990). For the categorization of hydrogen bonds, see: Desiraju & Steiner (1999).
Experimental
Crystal data
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Data collection
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Refinement
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Data collection: SMART (Bruker, 2001); cell SAINT (Bruker, 2001); data reduction: SAINT; program(s) used to solve structure: SHELXTL/PC (Sheldrick, 2008); program(s) used to refine structure: SHELXTL/PC and JANA2006 (Petricek et al., 2006); molecular graphics: PLATON (Spek, 2009) and JANA2006; software used to prepare material for publication: SHELXTL/PC.
Supporting information
10.1107/S1600536813007216/fb2278sup1.cif
contains datablocks global, I. DOI:Structure factors: contains datablock I. DOI: 10.1107/S1600536813007216/fb2278Isup2.hkl
Supporting information file. DOI: 10.1107/S1600536813007216/fb2278Isup3.cml
The synthesis of the title compound was carried out by heating of the mixture of sulphanilamide (3.4 g) and sulfuric acid (0.5 ml of 98% concentration) in 20 ml of water as the stoichiometric ratio of 2:1 (at 60°C) under reflux for 1 h. Colourless prismatic crystals of bis(4-sulfamoylanilinium) sulfate suitable for single-crystal X-ray analysis with the approximate size of 1.6 cm × 0.8 cm × 0.3 cm were obtained by slow evaporation at room temperature. The measured sample was cut from a bigger crystal.
All the H atoms were discernible in the difference
Nevertheless, the aryl H atoms were constrained and refined in the riding atom approximation: Caryl—Haryl = 0.93 Å and Uiso(Haryl)= 1.2Ueq(Caryl). The other atoms are involved in the N—H···O hydrogen bonds and after some tests also the ammonium H atoms were constrained in idealized tetrahedral symmetry because a distance-restrained yielded improbable differences in N2—H2A, N2—H2B, N2—H2C distances. The pertinent constraints were N2—Hammonium = 0.89 Å and Uiso(Hammonium)= 1.5Ueq(Nammonium). The distances of the primary amine H atoms to their N1 were restrained to 0.86 (1) Å while the Uiso(Hamine)= 1.2Ueq(Namine).Data collection: SMART (Bruker, 2001); cell
SAINT (Bruker, 2001); data reduction: SAINT (Bruker, 2001); program(s) used to solve structure: SHELXTL/PC (Sheldrick, 2008); program(s) used to refine structure: SHELXTL/PC (Sheldrick, 2008) and JANA2006 (Petricek et al., 2006); molecular graphics: PLATON (Spek, 2009) and JANA2006 (Petricek et al., 2006); software used to prepare material for publication: SHELXTL/PC (Sheldrick, 2008).Fig. 1. The title molecule with the atom numbering scheme. The displacement ellipsoids are shown at the 50% probability level. The H-bonds are shown as dashed lines. (Symmetry code: (i) 1-x, y, 3/2-z.) | |
Fig. 2. Section through the electron density map calculated from Fo passing through the atoms S2 and the atoms O21 and O21i (Petricek et al., 2006). Symmetry code: (i) 1-x, y, 3/2-z. The contours are given in 1 eÅ-3 levels. | |
Fig. 3. Section through the electron density map calculated from Fo passing through the atoms S2 and the atoms O22 and O22i (Petricek et al., 2006). Symmetry code: (i) 1-x, y, 3/2-z. The contours are given in 1 eÅ-3 levels. The curved character of the electron density of the depicted O atoms indicates libration movement. | |
Fig. 4. Packing diagram of the title compound viewed down the b axis. The H-bonds are shown as dashed lines. |
2C6H9N2O2S+·SO42− | F(000) = 920 |
Mr = 442.48 | Dx = 1.679 Mg m−3 |
Orthorhombic, Pbcn | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2n 2ab | Cell parameters from 2417 reflections |
a = 9.6543 (6) Å | θ = 2.4–23.9° |
b = 9.7591 (11) Å | µ = 0.48 mm−1 |
c = 18.579 (3) Å | T = 293 K |
V = 1750.5 (4) Å3 | Block, colourless |
Z = 4 | 0.24 × 0.22 × 0.19 mm |
Bruker SMART APEX CCD area-detector diffractometer | 1950 reflections with I > 2σ(I) |
Radiation source: fine-focus sealed tube | Rint = 0.025 |
Graphite monochromator | θmax = 27.8°, θmin = 2.2° |
ω scans | h = −12→12 |
18054 measured reflections | k = −12→12 |
2054 independent reflections | l = −24→23 |
Refinement on F2 | Secondary atom site location: difference Fourier map |
Least-squares matrix: full | Hydrogen site location: difference Fourier map |
R[F2 > 2σ(F2)] = 0.039 | H atoms treated by a mixture of independent and constrained refinement |
wR(F2) = 0.104 | w = 1/[σ2(Fo2) + (0.0478P)2 + 1.7836P] where P = (Fo2 + 2Fc2)/3 |
S = 1.05 | (Δ/σ)max = 0.001 |
2054 reflections | Δρmax = 0.69 e Å−3 |
131 parameters | Δρmin = −0.51 e Å−3 |
2 restraints | Extinction correction: SHELXTL/PC (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4 |
29 constraints | Extinction coefficient: 0.048 (2) |
Primary atom site location: structure-invariant direct methods |
2C6H9N2O2S+·SO42− | V = 1750.5 (4) Å3 |
Mr = 442.48 | Z = 4 |
Orthorhombic, Pbcn | Mo Kα radiation |
a = 9.6543 (6) Å | µ = 0.48 mm−1 |
b = 9.7591 (11) Å | T = 293 K |
c = 18.579 (3) Å | 0.24 × 0.22 × 0.19 mm |
Bruker SMART APEX CCD area-detector diffractometer | 1950 reflections with I > 2σ(I) |
18054 measured reflections | Rint = 0.025 |
2054 independent reflections |
R[F2 > 2σ(F2)] = 0.039 | 2 restraints |
wR(F2) = 0.104 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.05 | Δρmax = 0.69 e Å−3 |
2054 reflections | Δρmin = −0.51 e Å−3 |
131 parameters |
Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds 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 | ||
C1 | 0.11530 (19) | 0.63165 (19) | 0.54983 (9) | 0.0275 (4) | |
C2 | 0.0350 (2) | 0.6931 (2) | 0.49691 (11) | 0.0346 (4) | |
H2 | −0.0419 | 0.7451 | 0.5098 | 0.041* | |
C3 | 0.0693 (2) | 0.6772 (2) | 0.42437 (10) | 0.0349 (4) | |
H3 | 0.0161 | 0.7185 | 0.3887 | 0.042* | |
C4 | 0.18330 (18) | 0.59911 (18) | 0.40639 (9) | 0.0278 (4) | |
C5 | 0.2642 (2) | 0.5368 (2) | 0.45866 (10) | 0.0363 (4) | |
H5 | 0.3407 | 0.4846 | 0.4455 | 0.044* | |
C6 | 0.2300 (2) | 0.5530 (2) | 0.53135 (10) | 0.0368 (4) | |
H6 | 0.2833 | 0.5115 | 0.5669 | 0.044* | |
N1 | 0.1578 (2) | 0.7855 (2) | 0.66870 (10) | 0.0418 (4) | |
H1N | 0.234 (2) | 0.771 (3) | 0.6883 (13) | 0.050* | |
H2N | 0.118 (3) | 0.863 (2) | 0.6780 (15) | 0.050* | |
N2 | 0.21752 (18) | 0.57958 (18) | 0.32972 (8) | 0.0343 (4) | |
H2A | 0.1882 | 0.6516 | 0.3046 | 0.052* | |
H2B | 0.1762 | 0.5041 | 0.3135 | 0.052* | |
H2C | 0.3088 | 0.5712 | 0.3248 | 0.052* | |
S1 | 0.07157 (5) | 0.65527 (5) | 0.64256 (2) | 0.02962 (17) | |
O1 | 0.11508 (19) | 0.53240 (16) | 0.68009 (8) | 0.0447 (4) | |
O2 | −0.07144 (14) | 0.69235 (18) | 0.64486 (8) | 0.0401 (4) | |
S2 | 0.5000 | 0.61321 (7) | 0.7500 | 0.0330 (2) | |
O21 | 0.5039 (2) | 0.52764 (18) | 0.68459 (10) | 0.0586 (5) | |
O22 | 0.6198 (3) | 0.7004 (3) | 0.75120 (13) | 0.1099 (12) |
U11 | U22 | U33 | U12 | U13 | U23 | |
C1 | 0.0286 (8) | 0.0291 (8) | 0.0249 (8) | −0.0019 (7) | 0.0024 (7) | −0.0003 (6) |
C2 | 0.0336 (9) | 0.0373 (10) | 0.0328 (9) | 0.0103 (8) | 0.0029 (8) | 0.0007 (8) |
C3 | 0.0359 (10) | 0.0398 (10) | 0.0291 (9) | 0.0076 (8) | −0.0016 (7) | 0.0055 (8) |
C4 | 0.0298 (8) | 0.0287 (8) | 0.0249 (8) | −0.0040 (7) | 0.0036 (6) | −0.0001 (6) |
C5 | 0.0325 (9) | 0.0433 (11) | 0.0330 (9) | 0.0102 (8) | 0.0046 (8) | 0.0015 (8) |
C6 | 0.0343 (10) | 0.0469 (11) | 0.0293 (9) | 0.0109 (8) | 0.0000 (7) | 0.0046 (8) |
N1 | 0.0381 (9) | 0.0407 (10) | 0.0465 (10) | −0.0023 (8) | −0.0103 (8) | −0.0076 (8) |
N2 | 0.0371 (9) | 0.0398 (9) | 0.0261 (7) | −0.0027 (7) | 0.0044 (6) | −0.0013 (6) |
S1 | 0.0324 (3) | 0.0309 (3) | 0.0255 (2) | −0.00172 (17) | 0.00340 (16) | −0.00089 (16) |
O1 | 0.0638 (10) | 0.0385 (8) | 0.0317 (7) | 0.0043 (7) | 0.0071 (7) | 0.0072 (6) |
O2 | 0.0300 (7) | 0.0514 (9) | 0.0389 (8) | −0.0028 (6) | 0.0067 (6) | −0.0093 (6) |
S2 | 0.0239 (3) | 0.0230 (3) | 0.0521 (4) | 0.000 | −0.0031 (3) | 0.000 |
O21 | 0.0739 (12) | 0.0411 (9) | 0.0606 (11) | −0.0021 (8) | 0.0280 (9) | −0.0121 (8) |
O22 | 0.0993 (18) | 0.142 (2) | 0.0884 (16) | −0.0935 (18) | −0.0563 (14) | 0.0677 (16) |
C1—C2 | 1.389 (3) | N1—S1 | 1.5950 (19) |
C1—C6 | 1.390 (3) | N1—H1N | 0.834 (17) |
C1—S1 | 1.7887 (18) | N1—H2N | 0.866 (17) |
C2—C3 | 1.397 (3) | N2—H2A | 0.8900 |
C2—H2 | 0.9300 | N2—H2B | 0.8900 |
C3—C4 | 1.379 (3) | N2—H2C | 0.8900 |
C3—H3 | 0.9300 | S1—O2 | 1.4279 (15) |
C4—C5 | 1.386 (3) | S1—O1 | 1.4494 (15) |
C4—N2 | 1.475 (2) | S2—O22i | 1.4362 (19) |
C5—C6 | 1.399 (3) | S2—O22 | 1.436 (2) |
C5—H5 | 0.9300 | S2—O21i | 1.4750 (18) |
C6—H6 | 0.9300 | S2—O21 | 1.4751 (18) |
C2—C1—C6 | 120.56 (17) | H1N—N1—H2N | 117 (3) |
C2—C1—S1 | 119.64 (14) | C4—N2—H2A | 109.5 |
C6—C1—S1 | 119.80 (14) | C4—N2—H2B | 109.5 |
C1—C2—C3 | 120.16 (17) | H2A—N2—H2B | 109.5 |
C1—C2—H2 | 119.9 | C4—N2—H2C | 109.5 |
C3—C2—H2 | 119.9 | H2A—N2—H2C | 109.5 |
C4—C3—C2 | 119.00 (17) | H2B—N2—H2C | 109.5 |
C4—C3—H3 | 120.5 | O2—S1—O1 | 118.39 (10) |
C2—C3—H3 | 120.5 | O2—S1—N1 | 107.08 (10) |
C3—C4—C5 | 121.45 (17) | O1—S1—N1 | 111.18 (11) |
C3—C4—N2 | 118.95 (16) | O2—S1—C1 | 106.84 (9) |
C5—C4—N2 | 119.59 (17) | O1—S1—C1 | 106.76 (9) |
C4—C5—C6 | 119.60 (18) | N1—S1—C1 | 105.83 (10) |
C4—C5—H5 | 120.2 | O22i—S2—O22 | 107.4 (3) |
C6—C5—H5 | 120.2 | O22i—S2—O21i | 109.11 (16) |
C1—C6—C5 | 119.24 (17) | O22—S2—O21i | 110.07 (12) |
C1—C6—H6 | 120.4 | O22i—S2—O21 | 110.07 (12) |
C5—C6—H6 | 120.4 | O22—S2—O21 | 109.11 (16) |
S1—N1—H1N | 117.4 (19) | O21i—S2—O21 | 111.04 (16) |
S1—N1—H2N | 121.8 (19) | ||
C6—C1—C2—C3 | −0.4 (3) | S1—C1—C6—C5 | −179.13 (16) |
S1—C1—C2—C3 | 179.02 (16) | C4—C5—C6—C1 | −0.1 (3) |
C1—C2—C3—C4 | 0.3 (3) | C2—C1—S1—O2 | 21.96 (19) |
C2—C3—C4—C5 | −0.2 (3) | C6—C1—S1—O2 | −158.59 (17) |
C2—C3—C4—N2 | 178.55 (18) | C2—C1—S1—O1 | 149.55 (17) |
C3—C4—C5—C6 | 0.1 (3) | C6—C1—S1—O1 | −31.01 (19) |
N2—C4—C5—C6 | −178.65 (18) | C2—C1—S1—N1 | −91.92 (18) |
C2—C1—C6—C5 | 0.3 (3) | C6—C1—S1—N1 | 87.52 (18) |
Symmetry code: (i) −x+1, y, −z+3/2. |
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H1N···O22i | 0.84 (2) | 1.93 (2) | 2.743 (3) | 164 (3) |
N1—H2N···O21ii | 0.86 (2) | 1.99 (2) | 2.849 (3) | 168 (3) |
N2—H2B···O2iii | 0.89 | 2.30 | 3.043 (3) | 141 |
N2—H2B···O1iv | 0.89 | 2.57 | 3.146 (2) | 123 |
N2—H2A···O22v | 0.89 | 1.90 | 2.787 (3) | 177 |
N2—H2C···O21vi | 0.89 | 2.06 | 2.900 (3) | 158 |
Symmetry codes: (i) −x+1, y, −z+3/2; (ii) −x+1/2, y+1/2, z; (iii) −x, −y+1, −z+1; (iv) x, −y+1, z−1/2; (v) x−1/2, −y+3/2, −z+1; (vi) −x+1, −y+1, −z+1. |
Experimental details
Crystal data | |
Chemical formula | 2C6H9N2O2S+·SO42− |
Mr | 442.48 |
Crystal system, space group | Orthorhombic, Pbcn |
Temperature (K) | 293 |
a, b, c (Å) | 9.6543 (6), 9.7591 (11), 18.579 (3) |
V (Å3) | 1750.5 (4) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 0.48 |
Crystal size (mm) | 0.24 × 0.22 × 0.19 |
Data collection | |
Diffractometer | Bruker SMART APEX CCD area-detector diffractometer |
Absorption correction | – |
No. of measured, independent and observed [I > 2σ(I)] reflections | 18054, 2054, 1950 |
Rint | 0.025 |
(sin θ/λ)max (Å−1) | 0.655 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.039, 0.104, 1.05 |
No. of reflections | 2054 |
No. of parameters | 131 |
No. of restraints | 2 |
H-atom treatment | H atoms treated by a mixture of independent and constrained refinement |
Δρmax, Δρmin (e Å−3) | 0.69, −0.51 |
Computer programs: SMART (Bruker, 2001), SAINT (Bruker, 2001), SHELXTL/PC (Sheldrick, 2008) and JANA2006 (Petricek et al., 2006), PLATON (Spek, 2009) and JANA2006 (Petricek et al., 2006).
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H1N···O22i | 0.84 (2) | 1.93 (2) | 2.743 (3) | 164 (3) |
N1—H2N···O21ii | 0.86 (2) | 1.99 (2) | 2.849 (3) | 168 (3) |
N2—H2B···O2iii | 0.89 | 2.30 | 3.043 (3) | 141 |
N2—H2B···O1iv | 0.89 | 2.57 | 3.146 (2) | 123 |
N2—H2A···O22v | 0.89 | 1.90 | 2.787 (3) | 177 |
N2—H2C···O21vi | 0.89 | 2.06 | 2.900 (3) | 158 |
Symmetry codes: (i) −x+1, y, −z+3/2; (ii) −x+1/2, y+1/2, z; (iii) −x, −y+1, −z+1; (iv) x, −y+1, z−1/2; (v) x−1/2, −y+3/2, −z+1; (vi) −x+1, −y+1, −z+1. |
Acknowledgements
SPR and BRK thank the management of the Devanga Arts College for their support and encouragement and also extend their thanks to the University Grants Commission for the financial support of this work in the form of a Minor Research Project.
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.
Sulfonamides have been the first antibacterial drugs and paved the way for the antibiotic revolution in medicine. Sulfanilamides, which belong to sulfonamide drugs, act as competitive inhibitors for the enzyme dihydropteroate synthetase (DHPS). This enzyme is involved in the folate synthesis (Kent, 2000).
We have recently reported a nitrate complex of sulfanilamide (Pandiarajan et al., 2011). In continuation of our interest on the sulfanilamide complexes, the synthesis of the title compound and its title structure, bis(4-sulfamoylanilinium) sulfate, is described here.
In the title structure, the sulfate anion is situated in the special position on the twofold axis, thus the symmetry of this molecule is 2. The refinement has shown that the displacement ellipsoid of the sulfate atom O22 is extensively elongated while that of O21 has shown usual behaviour (Fig. 1). This is due to the libration movement as it is indicated by Figs. 2 and 3 which show the sections of the electron density maps (Petricek et al., 2006) through S2 and the atoms O21 and O22, respectively. Note the curved electron density pertinent to O22 (Fig. 3). The libration movement is also manifested by the values of the corrected S—O distances (Nardelli, 1995): The uncorrected values S2—O21 and S2—O22 are 1.475 (2) and 1.436 (2) Å, respectively, while the respective corrected values equal to 1.501 and 1.516 Å. The attempts to express the libration of the sulfate by TLS (Schomaker & Trueblood, 1968; JANA2006 (Petricek et al., 2006) failed in this case.
The geometric parameters of the cation in the title structure is in agreement with the reported structures of 4-sulfamoylanilinium nitrate (Pandiarajan et al., 2011) and 4-sulfamoylanilinium chloride (Zaouali Zgolli et al., 2010).
The crystal structure is stabilized through a three-dimensional hydrogen bonding network formed by strong N—H···O hydrogen bonds (Table 1, Fig. 4). (The nomenclature regarding the strength of the hydrogen bonds was taken from Desiraju & Steiner, 1999.) The sulfate oxygens as well as the oxygen O2 of the sulfonamyl group are the acceptors of these strong hydrogen bonds (Table 1) which are donated by the primary amine as well as by the ammonium groups. Among the N—H···O hydrogen bonds, one of the N—H···O hydrogen bonds is observed to be a bifurcated hydrogen bond, with one donor hydrogen (Table 1): N2—H2B···O2 (-x, -y+1, -z) and N2—H2B···O1 (x, -y+1, -z+1/2). All other hydrogen bonding interactions are cation-anion type. These hydrogen bonds are localized in layers parallel to (0 0 1) which are situated at z = 1/4 and z = 3/4. Hence, hydrophilic and hydrophobic regions alternate along c axis as a result of the arrangement of anions and the aromatic cationic parts.
Among the important graph set motifs pertinent to the hydrogen bonding in the structure can be named R22(16) (Etter et al., 1990): The cationic –NH3 group is bonded to the O atom of the S═O group of another cation through the N2—H2B···O2iii hydrogen bond (the symmetry code iii: -x, 1-y, 1-z). These bonds are involved in a ring motif R22(16) about the crystallographic inversion centre situated at the Wyckoff position 4a.
Among other graph-set motifs which can be discerned in this hydrogen bond pattern, C44(12) is worthwhile mentioning. This motif contains N2—H2A···O22v—S2v— O21v···H2Nvii-N1vii-H1Nvii···O22viii-S2viii-O21viii··· H2Cix-N2ix··· where the symmetry codes are v : -1/2+x, 3/2-y, 1-z; vii : -x, 2-y, 1-z; viii : 1-x, 2-y, -1/2+z; ix : -x, 1+y, 1/2-z.