Crystal structure of 4-sulfamoylanilinium di­hydrogen phosphate

Muthuselvi, C.; Mala, N.; Srinivasan, N.; Pandiarajan, S.; Krishnakumar, R.V.

doi:10.1107/S1600536814017462

organic compounds

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ISSN: 2056-9890

Volume 70| Part 9| September 2014| Pages o997-o998

doi:10.1107/S1600536814017462

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Crystal structure of 4-sulfamoylanilinium dihydrogen phosphate

C. Muthuselvi,^a N. Mala,^a N. Srinivasan,^b S. Pandiarajan ^a and R. V. Krishnakumar ^b ^*

^aDepartment of Physics, Devangar Arts College, Aruppukottai 626 101, Tamil Nadu, India, and ^bDepartment of Physics, Thiagarajar College, Madurai 625 009, Tamil Nadu, India
^*Correspondence e-mail: mailtorvkk@yahoo.co.in

Edited by W. T. A. Harrison, University of Aberdeen, Scotland (Received 12 July 2014; accepted 30 July 2014; online 13 August 2014)

In the crystal structure of the title molecular salt, C₆H₉N₂O₂S⁺·H₂PO₄⁻, the sulfomylalinium cations and the dihydrogen phosphate anions form independent [100] chains through N_s—H⋯O (s = sulfamoyl) and O—H⋯O hydrogen bonds, respectively. The chains are cross-linked by N_a—H⋯O (a = amine) hydrogen bonds, generating (010) sheets. Two C—H⋯O hydrogen bonds involving diametrically opposite C atoms in the benzene ring of the cation as donors form chains parallel to [202] in which P=O and P—OH groups are acceptors. Together, these interactions lead to a three-dimensional network.

Keywords: crystal structure; 4-sulfamoylanilinium; dihydrogen phosphate; hydrogen bonding; sulfanilamide derivatives; sulfa drugs.

CCDC reference: 1016950

1. Related literature

For background to sulfa drugs, see: Topacli & Kesimli (2001 ); Gelbrich et al. (2007 ). For structures of other molecular salts of the same cation, see: Anitha et al. (2013 ); Ravikumar et al. (2013 ); Pandiarajan et al. (2011 ); Zaouali Zgolli et al. (2010 ); Gelbrich et al. (2008 ); Chatterjee et al. (1981 ).

2. Experimental

2.1. Crystal data

C₆H₉N₂O₂S⁺·H₂O₄P⁻
M_r = 270.20
Monoclinic, P c
a = 4.8041 (7) Å
b = 10.8564 (15) Å
c = 10.3862 (15) Å
β = 101.067 (2)°
V = 531.62 (13) Å³
Z = 2
Mo Kα radiation
μ = 0.47 mm⁻¹
T = 294 K
0.28 × 0.18 × 0.10 mm

2.2. Data collection

Bruker SMART APEX CCD diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2001 ) T_min = 0.94, T_max = 0.99
6033 measured reflections
2512 independent reflections
2502 reflections with I > 2σ(I)
R_int = 0.018

2.3. Refinement

R[F² > 2σ(F²)] = 0.021
wR(F²) = 0.055
S = 1.06
2512 reflections
174 parameters
4 restraints
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.20 e Å⁻³
Δρ_min = −0.22 e Å⁻³
Absolute structure: Flack x determined using 1209 quotients [(I⁺)−(I⁻)]/[(I⁺)+(I⁻)] (Parsons & Flack, 2004 )
Absolute structure parameter: 0.069 (16)

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N1—H1A⋯O5ⁱ	0.87 (3)	1.89 (3)	2.760 (2)	174 (3)
N1—H1B⋯O6ⁱⁱ	0.90 (4)	1.96 (4)	2.856 (2)	170 (3)
N1—H1C⋯O6ⁱⁱⁱ	0.86 (4)	2.00 (4)	2.855 (2)	175 (3)
N2—H2A⋯O3^iv	0.86 (3)	2.25 (4)	3.076 (3)	161 (3)
N2—H2B⋯O2^v	0.88 (4)	2.10 (4)	2.886 (3)	149 (3)
O3—H3A⋯O1^vi	0.78 (2)	1.97 (2)	2.750 (3)	176 (4)
O4—H4A⋯O5^vi	0.80 (3)	1.76 (3)	2.500 (2)	154 (5)
C3—H3⋯O6^v	0.93	2.59	3.283 (3)	132
C6—H6⋯O4ⁱ	0.93	2.42	3.288 (3)	156
Symmetry codes: (i) x, y, z-1; (ii) $[x, -y, z-{\script{1\over 2}}]$ ; (iii) $[x+1, -y, z-{\script{1\over 2}}]$ ; (iv) $[x, -y+1, z-{\script{1\over 2}}]$ ; (v) x+1, y, z; (vi) x-1, y, z.

Data collection: SMART (Bruker, 2001); cell refinement: SAINT (Bruker, 2001); data reduction: SAINT; program(s) used to solve structure: SHELXS86 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL2013 (Sheldrick, 2008); molecular graphics: PLATON (Spek, 2009 ); software used to prepare material for publication: SHELXL2013.

Supporting information

CCDC reference: 1016950

Crystal structure: contains datablock I. DOI: 10.1107/S1600536814017462/hb7251sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536814017462/hb7251Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536814017462/hb7251Isup3.cml

checkCIF report

Comment top

Sulfanilamide (4-sulfamoyl aniline) and its derivatives known as sulfa drugs were used to treat bacterial infections (e.g. Gelbrich et al., 2007). Sulfa drugs were successfully deployed as chemotherapeutic agents (Topacli & Kesimli, 2001).

The perchlorate (Anitha, et al., 2013); nitrate, (Pandiarajan, et al., 2011); sulfate (Ravikumar et al., 2013) and hydrogen chloride (Zaouali Zgolli et al., 2010) complexes of sulfanilamide were already been reported. The present report on phosphate salt of sulfanilamide is part of a series of x-ray investigations being carried out on sulfanilamide-inorganic acid complexes.

The crystal structure of the title compound contains a cation with a protonated amino group and the dihydrogen phosphate anion C₆H₉N₂O₂S⁺.H₂PO₄^–(Fig. 1). The crystal structure features a three-dimensional hydrogen bonding network formed through N—H···O, O—H···O and C—H···O hydrogen bonds. The sulfomylalinium cations and the phosphate anions form independent chains through N—H···O [ N1—H1A···O5 ; N1—H1B··· O6 ; N1—H1C···O6 ; N2—H2A···O3 and N2—H2B···O2]. O—H···O [viz., O3—H3A,,,O1 (-1+x, y, z) and O4—H4A···O5 (-1+x, y, z)] hydrogen bonds along the shortest a-axis. Two C—H···O hydrogen bonds viz., C3—H3···O6 (1+x, y, z); C6—H6···O4 (x, y, -1+z) involving diametricaly opposite aryl carbon atoms in the benzene ring of the 4-sulfomylanilinum cation act as donors to form chains parallel to (202) in which P = O and P—OH are acceptors . This one dimensional chain is extended into a two dimensional layer parallel to the ac-plane through the same P—OH linking the adjacent phosophate anion and another P=O.

The overall picture of the complex intermolecular interactions may be visualized in terms of sinple graph-set motifs; viz., R₂²(9) motif generated through O3—H3A···O1 (-1+x, y, z) and C3—H3···O6 (1+x, y, z) hydrogen bonds, two R₆⁶(26) motifs generated involving O3—H3A···O1 (-1+x, y, z) and C6—H6···O4(x, y, -1+z); O4—H4A···O5(-1+x,y,z) hydrogen bond interactions (Fig. 2).

Synthesis and crystallization top

The title compound was synthesised by heating a mixture of sulphanilamide (3.4 g) and phosphoric 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. The solution upon allowing to evaporate under room temperature yielded colourless needles of the title salt.

Related literature top

For background to sulfa drugs, see: Topacli & Kesimli (2001); Gelbrich et al. (2007). For structures of other molecular salts of the same cation, see: Anitha et al. (2013); Ravikumar et al. (2013); Pandiarajan et al. (2011); Zaouali Zgolli et al. (2010); Gelbrich et al. (2008); Chatterjee et al. (1981).

Computing details top

Data collection: SMART (Bruker, 2001); cell refinement: SAINT (Bruker, 2001); data reduction: SAINT (Bruker, 2001); program(s) used to solve structure: SHELXS86 (Sheldrick, 2008); program(s) used to refine structure: SHELXL2013 (Sheldrick, 2008); molecular graphics: PLATON (Spek, 2009); software used to prepare material for publication: SHELXL2013 (Sheldrick, 2008).

Figures top

	Fig. 1. Molecular structure of (I) showing displacement ellipsoids drawn at the 50% probability level.
	Fig. 2. Hydrogen-bonding environment of the dihydrogen phosphate anion viewed along the b-axis. Other hydrogen bonds involving N atom and non-participating H atoms have been omitted for clarity.

4-Sulfamoylanilinium dihydrogen phosphate top

Crystal data top

C₆H₉N₂O₂S⁺·H₂O₄P⁻	Z = 2
M_r = 270.20	F(000) = 280
Monoclinic, Pc	D_x = 1.688 Mg m⁻³
a = 4.8041 (7) Å	Mo Kα radiation, λ = 0.71073 Å
b = 10.8564 (15) Å	µ = 0.47 mm⁻¹
c = 10.3862 (15) Å	T = 294 K
β = 101.067 (2)°	Needle, colourless
V = 531.62 (13) Å³	0.28 × 0.18 × 0.10 mm

Data collection top

Bruker SMART APEX CCD diffractometer	2502 reflections with I > 2σ(I)
ϕ and ω scans	R_int = 0.018
Absorption correction: multi-scan (SADABS; Bruker, 2001)	θ_max = 28.3°, θ_min = 1.9°
T_min = 0.94, T_max = 0.99	h = −6→6
6033 measured reflections	k = −14→14
2512 independent reflections	l = −13→13

Refinement top

Refinement on F²	H atoms treated by a mixture of independent and constrained refinement
Least-squares matrix: full	w = 1/[σ²(F_o²) + (0.0415P)² + 0.0212P] where P = (F_o² + 2F_c²)/3
R[F² > 2σ(F²)] = 0.021	(Δ/σ)_max < 0.001
wR(F²) = 0.055	Δρ_max = 0.20 e Å⁻³
S = 1.06	Δρ_min = −0.22 e Å⁻³
2512 reflections	Extinction correction: SHELXL2013 (Sheldrick, 2013), Fc^*=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4
174 parameters	Extinction coefficient: 0.099 (8)
4 restraints	Absolute structure: Flack x determined using 1209 quotients [(I⁺)-(I^-)]/[(I⁺)+(I^-)] (Parsons & Flack, 2004)
Hydrogen site location: mixed	Absolute structure parameter: 0.069 (16)

Crystal data top

C₆H₉N₂O₂S⁺·H₂O₄P⁻	V = 531.62 (13) Å³
M_r = 270.20	Z = 2
Monoclinic, Pc	Mo Kα radiation
a = 4.8041 (7) Å	µ = 0.47 mm⁻¹
b = 10.8564 (15) Å	T = 294 K
c = 10.3862 (15) Å	0.28 × 0.18 × 0.10 mm
β = 101.067 (2)°

Data collection top

Bruker SMART APEX CCD diffractometer	2512 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2001)	2502 reflections with I > 2σ(I)
T_min = 0.94, T_max = 0.99	R_int = 0.018
6033 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.021	H atoms treated by a mixture of independent and constrained refinement
wR(F²) = 0.055	Δρ_max = 0.20 e Å⁻³
S = 1.06	Δρ_min = −0.22 e Å⁻³
2512 reflections	Absolute structure: Flack x determined using 1209 quotients [(I⁺)-(I^-)]/[(I⁺)+(I^-)] (Parsons & Flack, 2004)
174 parameters	Absolute structure parameter: 0.069 (16)
4 restraints

Special details top

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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
C1	0.8098 (4)	0.14923 (16)	0.09044 (19)	0.0265 (3)
C2	1.0153 (5)	0.1497 (2)	0.2035 (2)	0.0365 (5)
H2	1.1473	0.0862	0.2199	0.044*
C3	1.0231 (5)	0.2455 (2)	0.2922 (2)	0.0364 (5)
H3	1.1623	0.2475	0.3680	0.044*
C4	0.8220 (4)	0.33816 (17)	0.26728 (19)	0.0271 (4)
C5	0.6183 (5)	0.3379 (2)	0.1532 (2)	0.0381 (5)
H5	0.4862	0.4013	0.1368	0.046*
C6	0.6116 (5)	0.2433 (2)	0.0639 (2)	0.0379 (5)
H6	0.4759	0.2426	−0.0132	0.046*
N1	0.7938 (4)	0.04600 (14)	−0.00122 (17)	0.0271 (3)
N2	0.9589 (4)	0.57959 (17)	0.3299 (2)	0.0352 (4)
O6	0.3160 (3)	0.08705 (13)	0.55239 (13)	0.0288 (3)
O5	0.7279 (3)	0.12348 (14)	0.74157 (13)	0.0298 (3)
O3	0.4839 (5)	0.30112 (15)	0.62757 (19)	0.0504 (5)
O4	0.2474 (3)	0.1676 (2)	0.77341 (17)	0.0506 (5)
O1	1.0051 (4)	0.42220 (15)	0.50222 (15)	0.0364 (3)
O2	0.5320 (3)	0.48636 (17)	0.38326 (17)	0.0400 (4)
P1	0.44104 (7)	0.16369 (4)	0.66908 (4)	0.02196 (12)
S1	0.82319 (8)	0.45858 (4)	0.38175 (5)	0.02634 (13)
H1A	0.760 (7)	0.072 (3)	−0.082 (3)	0.039 (7)*
H1B	0.639 (8)	0.001 (3)	0.006 (3)	0.046 (8)*
H1C	0.946 (8)	0.003 (3)	0.018 (3)	0.046 (8)*
H2A	0.855 (8)	0.611 (3)	0.261 (3)	0.050 (9)*
H2B	1.143 (8)	0.578 (3)	0.333 (3)	0.042 (8)*
H3A	0.343 (6)	0.334 (3)	0.594 (4)	0.052 (10)*
H4A	0.083 (6)	0.164 (4)	0.742 (4)	0.080 (14)*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C1	0.0272 (8)	0.0273 (8)	0.0245 (8)	−0.0007 (7)	0.0037 (7)	0.0024 (6)
C2	0.0368 (11)	0.0306 (9)	0.0372 (10)	0.0102 (8)	−0.0053 (9)	−0.0037 (8)
C3	0.0362 (11)	0.0335 (10)	0.0336 (10)	0.0084 (8)	−0.0084 (8)	−0.0030 (8)
C4	0.0288 (9)	0.0255 (8)	0.0270 (8)	0.0011 (6)	0.0052 (7)	0.0007 (6)
C5	0.0395 (11)	0.0363 (10)	0.0344 (10)	0.0145 (8)	−0.0036 (9)	0.0009 (8)
C6	0.0402 (11)	0.0400 (11)	0.0288 (9)	0.0105 (8)	−0.0053 (7)	−0.0011 (8)
N1	0.0287 (8)	0.0275 (7)	0.0243 (7)	−0.0007 (6)	0.0035 (6)	0.0016 (6)
N2	0.0310 (9)	0.0275 (8)	0.0462 (10)	0.0021 (7)	0.0050 (7)	0.0048 (7)
O6	0.0273 (6)	0.0314 (7)	0.0262 (6)	−0.0009 (5)	0.0014 (5)	−0.0035 (5)
O5	0.0189 (6)	0.0402 (8)	0.0290 (6)	0.0020 (5)	0.0017 (5)	0.0063 (6)
O3	0.0514 (10)	0.0261 (7)	0.0608 (11)	−0.0079 (7)	−0.0212 (8)	0.0091 (7)
O4	0.0195 (7)	0.0980 (15)	0.0357 (9)	−0.0113 (7)	0.0086 (6)	−0.0243 (8)
O1	0.0389 (8)	0.0414 (8)	0.0276 (6)	0.0079 (7)	0.0031 (6)	0.0013 (6)
O2	0.0250 (7)	0.0473 (8)	0.0492 (9)	0.0050 (6)	0.0107 (6)	−0.0059 (7)
P1	0.01703 (19)	0.0251 (2)	0.0230 (2)	−0.00087 (15)	0.00186 (14)	−0.00013 (15)
S1	0.0230 (2)	0.0275 (2)	0.0287 (2)	0.00361 (16)	0.00527 (14)	0.00025 (15)

Geometric parameters (Å, º) top

C1—C2	1.381 (3)	N1—H1B	0.90 (4)
C1—C6	1.387 (3)	N1—H1C	0.86 (4)
C1—N1	1.463 (2)	N2—S1	1.6048 (19)
C2—C3	1.386 (3)	N2—H2A	0.86 (3)
C2—H2	0.9300	N2—H2B	0.88 (4)
C3—C4	1.384 (3)	O6—P1	1.4975 (14)
C3—H3	0.9300	O5—P1	1.5027 (13)
C4—C5	1.384 (3)	O3—P1	1.5774 (17)
C4—S1	1.7665 (19)	O3—H3A	0.78 (2)
C5—C6	1.380 (3)	O4—P1	1.5583 (16)
C5—H5	0.9300	O4—H4A	0.80 (3)
C6—H6	0.9300	O1—S1	1.4371 (16)
N1—H1A	0.87 (3)	O2—S1	1.4339 (15)

C2—C1—C6	121.19 (18)	C1—N1—H1C	109 (2)
C2—C1—N1	119.70 (18)	H1A—N1—H1C	113 (3)
C6—C1—N1	119.08 (18)	H1B—N1—H1C	111 (3)
C1—C2—C3	119.45 (19)	S1—N2—H2A	113 (2)
C1—C2—H2	120.3	S1—N2—H2B	116 (2)
C3—C2—H2	120.3	H2A—N2—H2B	117 (3)
C4—C3—C2	119.49 (19)	P1—O3—H3A	114 (3)
C4—C3—H3	120.3	P1—O4—H4A	113 (3)
C2—C3—H3	120.3	O6—P1—O5	115.53 (9)
C3—C4—C5	120.79 (18)	O6—P1—O4	112.17 (9)
C3—C4—S1	120.00 (16)	O5—P1—O4	105.78 (9)
C5—C4—S1	119.21 (15)	O6—P1—O3	110.94 (9)
C6—C5—C4	119.90 (19)	O5—P1—O3	104.87 (10)
C6—C5—H5	120.0	O4—P1—O3	106.92 (13)
C4—C5—H5	120.0	O2—S1—O1	118.66 (10)
C5—C6—C1	119.15 (19)	O2—S1—N2	106.94 (11)
C5—C6—H6	120.4	O1—S1—N2	107.39 (11)
C1—C6—H6	120.4	O2—S1—C4	106.61 (10)
C1—N1—H1A	110.5 (19)	O1—S1—C4	107.79 (10)
C1—N1—H1B	108 (2)	N2—S1—C4	109.21 (10)
H1A—N1—H1B	105 (3)

C6—C1—C2—C3	0.3 (4)	C2—C1—C6—C5	−0.9 (3)
N1—C1—C2—C3	−177.7 (2)	N1—C1—C6—C5	177.0 (2)
C1—C2—C3—C4	1.0 (4)	C3—C4—S1—O2	−142.11 (19)
C2—C3—C4—C5	−1.7 (4)	C5—C4—S1—O2	37.8 (2)
C2—C3—C4—S1	178.21 (19)	C3—C4—S1—O1	−13.7 (2)
C3—C4—C5—C6	1.1 (4)	C5—C4—S1—O1	166.24 (18)
S1—C4—C5—C6	−178.88 (19)	C3—C4—S1—N2	102.68 (19)
C4—C5—C6—C1	0.3 (4)	C5—C4—S1—N2	−77.4 (2)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1A···O5ⁱ	0.87 (3)	1.89 (3)	2.760 (2)	174 (3)
N1—H1B···O6ⁱⁱ	0.90 (4)	1.96 (4)	2.856 (2)	170 (3)
N1—H1C···O6ⁱⁱⁱ	0.86 (4)	2.00 (4)	2.855 (2)	175 (3)
N2—H2A···O3^iv	0.86 (3)	2.25 (4)	3.076 (3)	161 (3)
N2—H2B···O2^v	0.88 (4)	2.10 (4)	2.886 (3)	149 (3)
O3—H3A···O1^vi	0.78 (2)	1.97 (2)	2.750 (3)	176 (4)
O4—H4A···O5^vi	0.80 (3)	1.76 (3)	2.500 (2)	154 (5)
C3—H3···O6^v	0.93	2.59	3.283 (3)	132
C6—H6···O4ⁱ	0.93	2.42	3.288 (3)	156

Symmetry codes: (i) x, y, z−1; (ii) x, −y, z−1/2; (iii) x+1, −y, z−1/2; (iv) x, −y+1, z−1/2; (v) x+1, y, z; (vi) x−1, y, z.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1A···O5ⁱ	0.87 (3)	1.89 (3)	2.760 (2)	174 (3)
N1—H1B···O6ⁱⁱ	0.90 (4)	1.96 (4)	2.856 (2)	170 (3)
N1—H1C···O6ⁱⁱⁱ	0.86 (4)	2.00 (4)	2.855 (2)	175 (3)
N2—H2A···O3^iv	0.86 (3)	2.25 (4)	3.076 (3)	161 (3)
N2—H2B···O2^v	0.88 (4)	2.10 (4)	2.886 (3)	149 (3)
O3—H3A···O1^vi	0.78 (2)	1.97 (2)	2.750 (3)	176 (4)
O4—H4A···O5^vi	0.80 (3)	1.76 (3)	2.500 (2)	154 (5)
C3—H3···O6^v	0.93	2.59	3.283 (3)	132
C6—H6···O4ⁱ	0.93	2.42	3.288 (3)	156

Symmetry codes: (i) x, y, z−1; (ii) x, −y, z−1/2; (iii) x+1, −y, z−1/2; (iv) x, −y+1, z−1/2; (v) x+1, y, z; (vi) x−1, y, z.

Acknowledgements

The authors thank the Sophisticated Analytical Instrumentation Facility (SAIF), Indian Institute of Technology, Chennai, for the data collection. CM, NM and SP thank the management of the Devangar Arts College for their encouragement.

References

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