Diiso­propyl­ammonium 4-amino­benzene­sulfonate

Sarr, B.; Diop, C.A.K.; Diop, L.; Blanchard, F.; Michaud, F.

doi:10.1107/S2414314616015455

organic compounds

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ISSN: 2414-3146

Volume 1| Part 10| October 2016| x161545

https://doi.org/10.1107/S2414314616015455

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Diisopropylammonium 4-aminobenzenesulfonate

Bougar Sarr,^a Cheikh Abdoul Khadir Diop,^a ^* Libasse Diop,^a Florent Blanchard ^b and Francois Michaud ^c

^aLaboratoire de Chimie Minérale et Analytique, Département de Chimie, Faculté des Sciences et Techniques, Université Cheikh Anta Diop, Dakar, Senegal, ^bInstitut de Chimie des Substances Naturelles, CNRS UPR 2301, Univ. Paris-Sud, Univ. Paris-Saclay, 1 av. de la Terrasse, F-91198 Gif-sur-Yvette Cedex, France, and ^cService Commun d'Analyse par Diffraction des Rayons X, Université de Bretagne Occidentale, 6 avenue Victor Le Gorgeu, CS 93837, F-29238 BREST cedex 3, France
^*Correspondence e-mail: bouks89@gmail.com

Edited by M. Weil, Vienna University of Technology, Austria (Received 4 August 2016; accepted 3 October 2016; online 7 October 2016)

The title molecular salt, C₆H₁₆N⁺·C₆H₆NO₃S⁻, was synthesized from a neutralization reaction between sulfanilic acid and diisopropylamine. The crystal structure consists of diisopropylammonium cations and 4-aminobenzenesulfonate (sulfanilate) anions interacting through a series of N—H⋯O and C—H⋯O hydrogen bonds, leading to the formation of a three-dimensional network structure.

Keywords: crystal structure; sulfanilic acid; sulfanilate anion; diisopropylammonium; 4-aminobenzenesulfonate; N—H⋯O hydrogen bonding.

CCDC reference: 1507861

Structure description

Sulfanilates of alkylammonium cations, such as the sulfanilates of methylammonium (Schreuer, 1999 ), guanidinium (Russell et al., 1994 ), triethylammonium (Li et al., 2007 ) or tetramethylammonium (Wang et al., 2016 ) have been reported. As a continuation of our work on alkylammonium salts (Sarr et al., 2012 ), in order to study their interactions with metallic halides, we synthesized the title molecular salt from a neutralization reaction between sulfanilic acid, the structure of which has been reported by Low & Glidewell (2002 ), and diisopropylamine. Sulfanilic acid, a strong organic acid with pK_a = 3.23, donates its sulfonic proton to diisopropylamine to give the title organic salt, C₆H₁₆N⁺·C₆H₆NO₃S⁻. Its asymmetric unit comprises one diisopropylammonium cation and one sulfanilate anion (Fig. 1). The protonation of diisopropylamine leads to an irregular tetrahedral arrangement around the ammonium atom N2, as reported in related structures (Sarr et al., 2012; Reiss & Meyer, 2011 ). The bond angles around this atom fall within normal ranges: 117.08 (18)° for angle C10—N2—C7, while the C—N—H2N/M angles are smaller and vary from 106.0 (13) to 109 (2) °. The arrangement around the sulfonate atom S1 is distorted tetrahedral, with the various O—S—C and O—S—O angles ranging between 106.82 (10)° for O1—S1—C1 to 112.51 (14)° for O2—S1—O1. In the SO₃⁻ group the three S—-O distances are slightly different, viz S1—O2 = 1.4201 (18) Å, S1—O3 = 1.4325 (19) Å and S1—O1 1.4446 (17) Å, due to their different roles in hydrogen bonding.

Figure 1
The structures of the molecular entities in the title salt. Displacement ellipsoids are drawn at the 50% probability level.

In the crystal, the ions are connected through N—H⋯O hydrogen bonds (Table 1). Atoms O1 and O2 of the sulfonate group are involved in rather strong N—H⋯O hydrogen bonding. Atom O1 acts as an acceptor of two hydrogen bonds N2—H2M⋯O1 and N2—H2N⋯O1ⁱ, forming a four-membered unit with inversion symmetry, enclosing an R₄²(8) ring motif (Table 1 and Fig. 2). These units are self-assembled through further N—H⋯O hydrogen bonds involving atom O2 and the amino group of the sulfanilate anion (Fig. 3 and Table 1), forming a three-dimensional network. The hydrogen-bonded assembly is consolidated by a weak N1—H1N⋯O3ⁱⁱⁱ hydrogen bond and two C—H⋯O hydrogen bonds (Fig. 3 and Table 1), again involving atom O3.

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N2—H2M⋯O1	0.89 (2)	2.03 (2)	2.878 (3)	159 (2)
N2—H2N⋯O1ⁱ	0.88 (1)	2.11 (2)	2.922 (3)	152 (2)
N1—H1M⋯O2ⁱⁱ	0.84 (2)	2.21 (2)	3.013 (3)	160 (3)
N1—H1N⋯O2ⁱⁱⁱ	0.84 (2)	2.57 (2)	3.316 (4)	149 (3)
N1—H1N⋯O3ⁱⁱⁱ	0.84 (2)	2.67 (2)	3.441 (4)	153 (3)
C10—H10⋯O3^iv	0.98	2.57	3.332 (3)	135
C12—H12B⋯O3ⁱ	0.96	2.58	3.468 (4)	155
Symmetry codes: (i) -x+1, -y, -z+1; (ii) $[x+1, -y+{\script{1\over 2}}, z+{\script{1\over 2}}]$ ; (iii) x+1, y, z; (iv) x, y, z-1.

Figure 2
A view of the four-membered unit formed by N—H⋯O hydrogen bonds (dashed lines; see Table 1

), enclosing an R₄²(8) ring motif.

Figure 3
The crystal packing of the title molecular salt, viewed approximately along the a axis. Hydrogen bonds (see Table 1

) are shown as dashed lines; for clarity, only H atoms involved in these interactions have been included.

Synthesis and crystallization

The title compound was obtained by addition of diisopropylamine (7.000 g, 0.069 mol) to an aqueous solution of sulfanilic acid (11.870 g, 0.068 mol) in an 1:1 ratio. The yellow solution obtained was stirred for one h and then filtered. Colourless plate-like crystals of the title molecular salt were obtained by slow evaporation of the filtrate after one week.

Refinement

Crystal data, data collection and structure refinement details are summarized in Table 2. The N-bound H atoms were located in difference Fourier maps and refined with distance and angle restraints: N—H and H⋯H distances involving atom N1 are N—H = 0.86 (2) Å and H⋯H = 1.49 (2) Å, and for atom N2 are N—H = 0.90 (2) Å and H⋯H = 1.45 (2) Å, with U_iso(H) = 1.2U_eq(N).

Table 2
Experimental details

Crystal data
Chemical formula	C₆H₁₆N⁺·C₆H₆NO₃S⁻
M_r	274.38
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	296
a, b, c (Å)	8.1712 (4), 20.1515 (9), 9.1360 (4)
β (°)	105.806 (5)
V (Å³)	1447.47 (11)
Z	4
Radiation type	Mo Kα
μ (mm⁻¹)	0.23
Crystal size (mm)	0.42 × 0.26 × 0.18

Data collection
Diffractometer	Agilent Xcalibur Sapphire2
Absorption correction	Analytical (CrysAlis PRO; Agilent, 2014 )
T_min, T_max	0.952, 0.970
No. of measured, independent and observed [I > 2σ(I)] reflections	6311, 2963, 2340
R_int	0.035
(sin θ/λ)_max (Å⁻¹)	0.625

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.050, 0.136, 1.04
No. of reflections	2963
No. of parameters	179
No. of restraints	14
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.34, −0.28
Computer programs: CrysAlis PRO (Agilent, 2014), SIR92 (Altomare et al., 1994 ), SHELXL97 (Sheldrick, 2008 ), ORTEP-3 for Windows and WinGX (Farrugia, 2012 ), Mercury (Macrae et al., 2008 ), PLATON (Spek, 2009 ) and publCIF (Westrip, 2010 ).

Structural data

CCDC reference: 1507861

Crystal structure: contains datablocks Global, I. DOI: https://doi.org/10.1107/S2414314616015455/wm5316sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2414314616015455/wm5316Isup2.hkl

Supporting information file. DOI: https://doi.org/10.1107/S2414314616015455/wm5316Isup3.cml

checkCIF report

Computing details top

Data collection: CrysAlis PRO (Agilent, 2014); cell refinement: CrysAlis PRO (Agilent, 2014); data reduction: CrysAlis PRO (Agilent, 2014); program(s) used to solve structure: SIR92 (Altomare et al., 1994); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012) and Mercury (Macrae et al., 2008); software used to prepare material for publication: WinGX (Farrugia, 2012), PLATON (Spek, 2009) and publCIF (Westrip, 2010).

Diisopropylammonium 4-aminobenzenesulfonate top

Crystal data top

C₆H₁₆N⁺·C₆H₆NO₃S⁻	F(000) = 592
M_r = 274.38	D_x = 1.259 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 2619 reflections
a = 8.1712 (4) Å	θ = 3.8–27.1°
b = 20.1515 (9) Å	µ = 0.23 mm⁻¹
c = 9.1360 (4) Å	T = 296 K
β = 105.806 (5)°	Fragment of big plate, colourless
V = 1447.47 (11) Å³	0.42 × 0.26 × 0.18 mm
Z = 4

Data collection top

Agilent Xcalibur Sapphire2 diffractometer	2963 independent reflections
Radiation source: Enhance (Mo) X-ray Source	2340 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.035
Detector resolution: 8.3622 pixels mm^-1	θ_max = 26.4°, θ_min = 3.6°
ω scans	h = −9→10
Absorption correction: analytical (CrysAlis PRO; Agilent, 2014)	k = −24→25
T_min = 0.952, T_max = 0.970	l = −11→11
6311 measured reflections

Refinement top

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)] = 0.050	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.136	H atoms treated by a mixture of independent and constrained refinement
S = 1.04	w = 1/[σ²(F_o²) + (0.0632P)² + 0.5536P] where P = (F_o² + 2F_c²)/3
2963 reflections	(Δ/σ)_max < 0.001
179 parameters	Δρ_max = 0.34 e Å⁻³
14 restraints	Δρ_min = −0.28 e Å⁻³

Special details top

Geometry. All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'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 > 2σ(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

	x	y	z	U_iso*/U_eq
C1	0.8387 (2)	0.15317 (10)	0.7706 (2)	0.0370 (4)
C2	0.8828 (3)	0.20191 (11)	0.8832 (2)	0.0462 (5)
H2	0.8014	0.2179	0.9284	0.055*
C3	1.0462 (3)	0.22647 (11)	0.9277 (3)	0.0527 (6)
H3	1.0738	0.259	1.0027	0.063*
C4	1.1704 (3)	0.20355 (11)	0.8624 (3)	0.0469 (5)
C5	1.1258 (3)	0.15426 (11)	0.7514 (2)	0.0448 (5)
H5	1.2074	0.1377	0.7073	0.054*
C6	0.9619 (3)	0.12987 (10)	0.7063 (2)	0.0415 (5)
H6	0.9342	0.0973	0.6315	0.05*
N1	1.3337 (3)	0.22806 (13)	0.9042 (3)	0.0775 (8)
S1	0.62887 (6)	0.12319 (3)	0.71455 (6)	0.04264 (19)
O1	0.6264 (2)	0.06898 (9)	0.6105 (2)	0.0681 (5)
O2	0.5214 (2)	0.17641 (10)	0.6456 (3)	0.1034 (9)
O3	0.5882 (3)	0.09977 (13)	0.8485 (2)	0.0992 (8)
H1M	1.362 (4)	0.2562 (15)	0.975 (3)	0.119*
H1N	1.405 (3)	0.2074 (16)	0.871 (4)	0.119*
C7	0.2667 (3)	0.09559 (11)	0.2422 (3)	0.0511 (6)
H7	0.2799	0.1423	0.2176	0.061*
C8	0.1624 (4)	0.06106 (14)	0.1017 (3)	0.0700 (8)
H8A	0.2188	0.0645	0.0225	0.105*
H8B	0.0524	0.0816	0.0687	0.105*
H8C	0.1494	0.0151	0.1241	0.105*
C9	0.1832 (4)	0.09238 (17)	0.3702 (3)	0.0785 (9)
H9A	0.1652	0.0468	0.3924	0.118*
H9B	0.0759	0.1151	0.3407	0.118*
H9C	0.2554	0.1132	0.459	0.118*
C10	0.5643 (3)	0.08053 (12)	0.2043 (3)	0.0547 (6)
H10	0.5049	0.0785	0.0957	0.066*
C11	0.6339 (4)	0.14973 (14)	0.2419 (4)	0.0739 (8)
H11A	0.6931	0.1523	0.348	0.111*
H11B	0.5419	0.181	0.2191	0.111*
H11C	0.711	0.1599	0.1823	0.111*
C12	0.7029 (4)	0.02934 (15)	0.2389 (4)	0.0865 (10)
H12A	0.7822	0.0387	0.1809	0.13*
H12B	0.6543	−0.0138	0.2123	0.13*
H12C	0.761	0.0305	0.3454	0.13*
N2	0.4402 (2)	0.06439 (9)	0.2941 (2)	0.0454 (4)
H2M	0.489 (2)	0.0764 (11)	0.3896 (18)	0.054*
H2N	0.423 (2)	0.0211 (7)	0.292 (3)	0.054*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C1	0.0406 (10)	0.0316 (10)	0.0346 (10)	−0.0003 (8)	0.0031 (8)	0.0024 (8)
C2	0.0475 (12)	0.0402 (11)	0.0500 (12)	0.0032 (10)	0.0118 (10)	−0.0093 (9)
C3	0.0564 (13)	0.0411 (12)	0.0551 (13)	−0.0046 (10)	0.0059 (11)	−0.0181 (10)
C4	0.0448 (12)	0.0404 (11)	0.0509 (12)	−0.0049 (10)	0.0051 (10)	−0.0006 (10)
C5	0.0447 (12)	0.0476 (12)	0.0432 (11)	−0.0021 (10)	0.0140 (9)	−0.0033 (9)
C6	0.0503 (12)	0.0410 (11)	0.0324 (10)	−0.0051 (9)	0.0100 (9)	−0.0061 (8)
N1	0.0490 (13)	0.0770 (18)	0.103 (2)	−0.0183 (12)	0.0153 (13)	−0.0326 (14)
S1	0.0397 (3)	0.0396 (3)	0.0442 (3)	−0.0028 (2)	0.0039 (2)	0.0011 (2)
O1	0.0552 (10)	0.0690 (12)	0.0768 (12)	−0.0175 (9)	0.0123 (9)	−0.0323 (10)
O2	0.0505 (11)	0.0571 (12)	0.173 (2)	0.0051 (9)	−0.0205 (13)	0.0298 (14)
O3	0.0780 (14)	0.162 (2)	0.0608 (12)	−0.0538 (15)	0.0235 (10)	0.0010 (14)
C7	0.0507 (13)	0.0405 (12)	0.0561 (13)	−0.0019 (10)	0.0041 (10)	−0.0012 (10)
C8	0.0728 (17)	0.0691 (17)	0.0521 (14)	−0.0021 (14)	−0.0102 (12)	0.0000 (13)
C9	0.0555 (16)	0.109 (2)	0.0722 (18)	−0.0051 (16)	0.0195 (13)	−0.0246 (18)
C10	0.0621 (14)	0.0582 (14)	0.0486 (13)	−0.0153 (12)	0.0231 (11)	−0.0065 (11)
C11	0.085 (2)	0.0542 (16)	0.090 (2)	−0.0174 (15)	0.0366 (17)	0.0077 (14)
C12	0.078 (2)	0.0658 (19)	0.134 (3)	−0.0093 (16)	0.060 (2)	−0.0197 (19)
N2	0.0478 (10)	0.0454 (10)	0.0415 (9)	−0.0075 (9)	0.0096 (8)	0.0018 (8)

Geometric parameters (Å, º) top

C1—C6	1.379 (3)	C7—H7	0.98
C1—C2	1.396 (3)	C8—H8A	0.96
C1—S1	1.758 (2)	C8—H8B	0.96
C2—C3	1.377 (3)	C8—H8C	0.96
C2—H2	0.93	C9—H9A	0.96
C3—C4	1.389 (3)	C9—H9B	0.96
C3—H3	0.93	C9—H9C	0.96
C4—N1	1.376 (3)	C10—C12	1.501 (4)
C4—C5	1.395 (3)	C10—N2	1.503 (3)
C5—C6	1.380 (3)	C10—C11	1.510 (3)
C5—H5	0.93	C10—H10	0.98
C6—H6	0.93	C11—H11A	0.96
N1—H1M	0.841 (17)	C11—H11B	0.96
N1—H1N	0.839 (17)	C11—H11C	0.96
S1—O2	1.4201 (18)	C12—H12A	0.96
S1—O3	1.4325 (19)	C12—H12B	0.96
S1—O1	1.4446 (17)	C12—H12C	0.96
C7—C8	1.504 (3)	N2—H2M	0.888 (15)
C7—N2	1.505 (3)	N2—H2N	0.884 (14)
C7—C9	1.507 (4)

C6—C1—C2	118.81 (19)	H8A—C8—H8B	109.5
C6—C1—S1	121.74 (15)	C7—C8—H8C	109.5
C2—C1—S1	119.45 (16)	H8A—C8—H8C	109.5
C3—C2—C1	120.3 (2)	H8B—C8—H8C	109.5
C3—C2—H2	119.9	C7—C9—H9A	109.5
C1—C2—H2	119.9	C7—C9—H9B	109.5
C2—C3—C4	121.1 (2)	H9A—C9—H9B	109.5
C2—C3—H3	119.4	C7—C9—H9C	109.5
C4—C3—H3	119.4	H9A—C9—H9C	109.5
N1—C4—C3	121.9 (2)	H9B—C9—H9C	109.5
N1—C4—C5	119.9 (2)	C12—C10—N2	108.6 (2)
C3—C4—C5	118.1 (2)	C12—C10—C11	111.8 (2)
C6—C5—C4	120.7 (2)	N2—C10—C11	110.13 (19)
C6—C5—H5	119.6	C12—C10—H10	108.7
C4—C5—H5	119.6	N2—C10—H10	108.7
C1—C6—C5	120.85 (19)	C11—C10—H10	108.7
C1—C6—H6	119.6	C10—C11—H11A	109.5
C5—C6—H6	119.6	C10—C11—H11B	109.5
C4—N1—H1M	120 (2)	H11A—C11—H11B	109.5
C4—N1—H1N	116 (2)	C10—C11—H11C	109.5
H1M—N1—H1N	123 (3)	H11A—C11—H11C	109.5
O2—S1—O3	111.62 (17)	H11B—C11—H11C	109.5
O2—S1—O1	112.51 (14)	C10—C12—H12A	109.5
O3—S1—O1	110.36 (13)	C10—C12—H12B	109.5
O2—S1—C1	107.83 (10)	H12A—C12—H12B	109.5
O3—S1—C1	107.42 (10)	C10—C12—H12C	109.5
O1—S1—C1	106.82 (10)	H12A—C12—H12C	109.5
C8—C7—N2	110.0 (2)	H12B—C12—H12C	109.5
C8—C7—C9	111.8 (2)	C10—N2—C7	117.08 (18)
N2—C7—C9	108.9 (2)	C10—N2—H2M	107.0 (13)
C8—C7—H7	108.7	C7—N2—H2M	108.9 (13)
N2—C7—H7	108.7	C10—N2—H2N	109.0 (13)
C9—C7—H7	108.7	C7—N2—H2N	106.0 (13)
C7—C8—H8A	109.5	H2M—N2—H2N	109 (2)
C7—C8—H8B	109.5

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N2—H2M···O1	0.89 (2)	2.03 (2)	2.878 (3)	159 (2)
N2—H2N···O1ⁱ	0.88 (1)	2.11 (2)	2.922 (3)	152 (2)
N1—H1M···O2ⁱⁱ	0.84 (2)	2.21 (2)	3.013 (3)	160 (3)
N1—H1N···O2ⁱⁱⁱ	0.84 (2)	2.57 (2)	3.316 (4)	149 (3)
N1—H1N···O3ⁱⁱⁱ	0.84 (2)	2.67 (2)	3.441 (4)	153 (3)
C10—H10···O3^iv	0.98	2.57	3.332 (3)	135
C12—H12B···O3ⁱ	0.96	2.58	3.468 (4)	155

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

Acknowledgements

The authors acknowledge the Cheikh Anta Diop University, Dakar, Senegal, the Institut de Chimie des Substances Naturelles – CNRS UPR 2301, University Paris-Sud and the Service Commun d'Analyse par Diffraction des Rayons X, Université de Bretagne Occidentale, for financial support.

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