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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

(Received 18 January 2013; accepted 15 March 2013; online 28 March 2013)

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 crystal structure 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[Kent, M. (2000). Advanced Biology, p. 46. New York: Oxford University Press Inc.]). For related structures, see: Pandiarajan et al. (2011[Pandiarajan, S., Balasubramanian, S., Ravikumar, B. & Athimoolam, S. (2011). Acta Cryst. E67, o2788.]); Zaouali Zgolli et al. (2010[Zaouali Zgolli, D., Boughzala, H. & Driss, A. (2010). Acta Cryst. E66, o1488.]). For correction of the S—O distances in the sulfate anion due to libration movement, see: Nardelli (1995[Nardelli, M. (1995). J. Appl. Cryst. 28, 659.]). For TLS approximation, see: Schomaker & Trueblood (1968[Schomaker, V. & Trueblood, K. N. (1968). Acta Cryst. B24, 63-76.]). For graph-set motifs, see: Etter et al. (1990[Etter, M. C., MacDonald, J. C. & Bernstein, J. (1990). Acta Cryst. B46, 256-262.]). For the categorization of hydrogen bonds, see: Desiraju & Steiner (1999[Desiraju, G. R. & Steiner, T. (1999). The Weak Hydrogen Bond in Structural Chemistry and Biology, p. 13. International Union of Crystallography and Oxford Science Publications.]).

[Scheme 1]

Experimental

Crystal data
  • 2C6H9N2O2S+·SO42−

  • Mr = 442.48

  • Orthorhombic, P b c n

  • a = 9.6543 (6) Å

  • b = 9.7591 (11) Å

  • c = 18.579 (3) Å

  • V = 1750.5 (4) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.48 mm−1

  • T = 293 K

  • 0.24 × 0.22 × 0.19 mm

Data collection
  • Bruker SMART APEX CCD area-detector diffractometer

  • 18054 measured reflections

  • 2054 independent reflections

  • 1950 reflections with I > 2σ(I)

  • Rint = 0.025

Refinement
  • R[F2 > 2σ(F2)] = 0.039

  • wR(F2) = 0.104

  • S = 1.05

  • 2054 reflections

  • 131 parameters

  • 2 restraints

  • H atoms treated by a mixture of independent and constrained refinement

  • Δρmax = 0.69 e Å−3

  • Δρmin = −0.51 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA 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+{\script{3\over 2}}]; (ii) [-x+{\script{1\over 2}}, y+{\script{1\over 2}}, z]; (iii) -x, -y+1, -z+1; (iv) [x, -y+1, z-{\script{1\over 2}}]; (v) [x-{\script{1\over 2}}, -y+{\script{3\over 2}}, -z+1]; (vi) -x+1, -y+1, -z+1.

Data collection: SMART (Bruker, 2001[Bruker (2001). SAINT and SMART. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2001[Bruker (2001). SAINT and SMART. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXTL/PC (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXTL/PC and JANA2006 (Petricek et al., 2006[Petricek, V., Dusek, M. & Palatinus, L. (2006). JANA2006. Institute of Physics of the Czech Academy of Sciences, Prague, Czech Republic.]); molecular graphics: PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]) and JANA2006; software used to prepare material for publication: SHELXTL/PC.

Supporting information


Comment top

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 SO 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.

Related literature top

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 top

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.

Refinement top

All the H atoms were discernible in the difference electron density map. 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 refinement 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 carrier atom N1 were restrained to 0.86 (1) Å while the Uiso(Hamine)= 1.2Ueq(Namine).

Computing details top

Data collection: SMART (Bruker, 2001); cell refinement: 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).

Figures top
[Figure 1] 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.)
[Figure 2] 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.
[Figure 3] 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.
[Figure 4] Fig. 4. Packing diagram of the title compound viewed down the b axis. The H-bonds are shown as dashed lines.
Bis(4-sulfamoylanilinium) sulfate top
Crystal data top
2C6H9N2O2S+·SO42F(000) = 920
Mr = 442.48Dx = 1.679 Mg m3
Orthorhombic, PbcnMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2n 2abCell parameters from 2417 reflections
a = 9.6543 (6) Åθ = 2.4–23.9°
b = 9.7591 (11) ŵ = 0.48 mm1
c = 18.579 (3) ÅT = 293 K
V = 1750.5 (4) Å3Block, colourless
Z = 40.24 × 0.22 × 0.19 mm
Data collection top
Bruker SMART APEX CCD area-detector
diffractometer
1950 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.025
Graphite monochromatorθmax = 27.8°, θmin = 2.2°
ω scansh = 1212
18054 measured reflectionsk = 1212
2054 independent reflectionsl = 2423
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.039H 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 reflectionsΔρmax = 0.69 e Å3
131 parametersΔρmin = 0.51 e Å3
2 restraintsExtinction correction: SHELXTL/PC (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
29 constraintsExtinction coefficient: 0.048 (2)
Primary atom site location: structure-invariant direct methods
Crystal data top
2C6H9N2O2S+·SO42V = 1750.5 (4) Å3
Mr = 442.48Z = 4
Orthorhombic, PbcnMo Kα radiation
a = 9.6543 (6) ŵ = 0.48 mm1
b = 9.7591 (11) ÅT = 293 K
c = 18.579 (3) Å0.24 × 0.22 × 0.19 mm
Data collection top
Bruker SMART APEX CCD area-detector
diffractometer
1950 reflections with I > 2σ(I)
18054 measured reflectionsRint = 0.025
2054 independent reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0392 restraints
wR(F2) = 0.104H atoms treated by a mixture of independent and constrained refinement
S = 1.05Δρmax = 0.69 e Å3
2054 reflectionsΔρmin = 0.51 e Å3
131 parameters
Special details top

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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
C10.11530 (19)0.63165 (19)0.54983 (9)0.0275 (4)
C20.0350 (2)0.6931 (2)0.49691 (11)0.0346 (4)
H20.04190.74510.50980.041*
C30.0693 (2)0.6772 (2)0.42437 (10)0.0349 (4)
H30.01610.71850.38870.042*
C40.18330 (18)0.59911 (18)0.40639 (9)0.0278 (4)
C50.2642 (2)0.5368 (2)0.45866 (10)0.0363 (4)
H50.34070.48460.44550.044*
C60.2300 (2)0.5530 (2)0.53135 (10)0.0368 (4)
H60.28330.51150.56690.044*
N10.1578 (2)0.7855 (2)0.66870 (10)0.0418 (4)
H1N0.234 (2)0.771 (3)0.6883 (13)0.050*
H2N0.118 (3)0.863 (2)0.6780 (15)0.050*
N20.21752 (18)0.57958 (18)0.32972 (8)0.0343 (4)
H2A0.18820.65160.30460.052*
H2B0.17620.50410.31350.052*
H2C0.30880.57120.32480.052*
S10.07157 (5)0.65527 (5)0.64256 (2)0.02962 (17)
O10.11508 (19)0.53240 (16)0.68009 (8)0.0447 (4)
O20.07144 (14)0.69235 (18)0.64486 (8)0.0401 (4)
S20.50000.61321 (7)0.75000.0330 (2)
O210.5039 (2)0.52764 (18)0.68459 (10)0.0586 (5)
O220.6198 (3)0.7004 (3)0.75120 (13)0.1099 (12)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0286 (8)0.0291 (8)0.0249 (8)0.0019 (7)0.0024 (7)0.0003 (6)
C20.0336 (9)0.0373 (10)0.0328 (9)0.0103 (8)0.0029 (8)0.0007 (8)
C30.0359 (10)0.0398 (10)0.0291 (9)0.0076 (8)0.0016 (7)0.0055 (8)
C40.0298 (8)0.0287 (8)0.0249 (8)0.0040 (7)0.0036 (6)0.0001 (6)
C50.0325 (9)0.0433 (11)0.0330 (9)0.0102 (8)0.0046 (8)0.0015 (8)
C60.0343 (10)0.0469 (11)0.0293 (9)0.0109 (8)0.0000 (7)0.0046 (8)
N10.0381 (9)0.0407 (10)0.0465 (10)0.0023 (8)0.0103 (8)0.0076 (8)
N20.0371 (9)0.0398 (9)0.0261 (7)0.0027 (7)0.0044 (6)0.0013 (6)
S10.0324 (3)0.0309 (3)0.0255 (2)0.00172 (17)0.00340 (16)0.00089 (16)
O10.0638 (10)0.0385 (8)0.0317 (7)0.0043 (7)0.0071 (7)0.0072 (6)
O20.0300 (7)0.0514 (9)0.0389 (8)0.0028 (6)0.0067 (6)0.0093 (6)
S20.0239 (3)0.0230 (3)0.0521 (4)0.0000.0031 (3)0.000
O210.0739 (12)0.0411 (9)0.0606 (11)0.0021 (8)0.0280 (9)0.0121 (8)
O220.0993 (18)0.142 (2)0.0884 (16)0.0935 (18)0.0563 (14)0.0677 (16)
Geometric parameters (Å, º) top
C1—C21.389 (3)N1—S11.5950 (19)
C1—C61.390 (3)N1—H1N0.834 (17)
C1—S11.7887 (18)N1—H2N0.866 (17)
C2—C31.397 (3)N2—H2A0.8900
C2—H20.9300N2—H2B0.8900
C3—C41.379 (3)N2—H2C0.8900
C3—H30.9300S1—O21.4279 (15)
C4—C51.386 (3)S1—O11.4494 (15)
C4—N21.475 (2)S2—O22i1.4362 (19)
C5—C61.399 (3)S2—O221.436 (2)
C5—H50.9300S2—O21i1.4750 (18)
C6—H60.9300S2—O211.4751 (18)
C2—C1—C6120.56 (17)H1N—N1—H2N117 (3)
C2—C1—S1119.64 (14)C4—N2—H2A109.5
C6—C1—S1119.80 (14)C4—N2—H2B109.5
C1—C2—C3120.16 (17)H2A—N2—H2B109.5
C1—C2—H2119.9C4—N2—H2C109.5
C3—C2—H2119.9H2A—N2—H2C109.5
C4—C3—C2119.00 (17)H2B—N2—H2C109.5
C4—C3—H3120.5O2—S1—O1118.39 (10)
C2—C3—H3120.5O2—S1—N1107.08 (10)
C3—C4—C5121.45 (17)O1—S1—N1111.18 (11)
C3—C4—N2118.95 (16)O2—S1—C1106.84 (9)
C5—C4—N2119.59 (17)O1—S1—C1106.76 (9)
C4—C5—C6119.60 (18)N1—S1—C1105.83 (10)
C4—C5—H5120.2O22i—S2—O22107.4 (3)
C6—C5—H5120.2O22i—S2—O21i109.11 (16)
C1—C6—C5119.24 (17)O22—S2—O21i110.07 (12)
C1—C6—H6120.4O22i—S2—O21110.07 (12)
C5—C6—H6120.4O22—S2—O21109.11 (16)
S1—N1—H1N117.4 (19)O21i—S2—O21111.04 (16)
S1—N1—H2N121.8 (19)
C6—C1—C2—C30.4 (3)S1—C1—C6—C5179.13 (16)
S1—C1—C2—C3179.02 (16)C4—C5—C6—C10.1 (3)
C1—C2—C3—C40.3 (3)C2—C1—S1—O221.96 (19)
C2—C3—C4—C50.2 (3)C6—C1—S1—O2158.59 (17)
C2—C3—C4—N2178.55 (18)C2—C1—S1—O1149.55 (17)
C3—C4—C5—C60.1 (3)C6—C1—S1—O131.01 (19)
N2—C4—C5—C6178.65 (18)C2—C1—S1—N191.92 (18)
C2—C1—C6—C50.3 (3)C6—C1—S1—N187.52 (18)
Symmetry code: (i) x+1, y, z+3/2.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1N···O22i0.84 (2)1.93 (2)2.743 (3)164 (3)
N1—H2N···O21ii0.86 (2)1.99 (2)2.849 (3)168 (3)
N2—H2B···O2iii0.892.303.043 (3)141
N2—H2B···O1iv0.892.573.146 (2)123
N2—H2A···O22v0.891.902.787 (3)177
N2—H2C···O21vi0.892.062.900 (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, z1/2; (v) x1/2, y+3/2, z+1; (vi) x+1, y+1, z+1.

Experimental details

Crystal data
Chemical formula2C6H9N2O2S+·SO42
Mr442.48
Crystal system, space groupOrthorhombic, Pbcn
Temperature (K)293
a, b, c (Å)9.6543 (6), 9.7591 (11), 18.579 (3)
V3)1750.5 (4)
Z4
Radiation typeMo Kα
µ (mm1)0.48
Crystal size (mm)0.24 × 0.22 × 0.19
Data collection
DiffractometerBruker SMART APEX CCD area-detector
diffractometer
Absorption correction
No. of measured, independent and
observed [I > 2σ(I)] reflections
18054, 2054, 1950
Rint0.025
(sin θ/λ)max1)0.655
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.039, 0.104, 1.05
No. of reflections2054
No. of parameters131
No. of restraints2
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)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).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1N···O22i0.84 (2)1.93 (2)2.743 (3)164 (3)
N1—H2N···O21ii0.86 (2)1.99 (2)2.849 (3)168 (3)
N2—H2B···O2iii0.892.303.043 (3)141
N2—H2B···O1iv0.892.573.146 (2)123
N2—H2A···O22v0.891.902.787 (3)177
N2—H2C···O21vi0.892.062.900 (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, z1/2; (v) x1/2, 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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