Bis[3-(dihydroxy­boryl)anilinium] sulfate

Araceli Vega; Rolando Luna; Hugo Tlahuext; Herbert Höpfl

doi:10.1107/S1600536810012092

. 2010 Apr 10;66(Pt 5):o1035–o1036. doi: 10.1107/S1600536810012092

Bis[3-(dihydroxyboryl)anilinium] sulfate

Araceli Vega ^a, Rolando Luna ^a, Hugo Tlahuext ^a, Herbert Höpfl ^a,^*

PMCID: PMC2979015 PMID: 21579098

Abstract

In the title compound, 2C₆H₉BNO₂ ⁺·SO₄ ²⁻, the dihydroxyboryl group of one of the two independent boronic acid molecules participates in (B)O—H⋯O_B and N—H⋯O_B hydrogen bonds, while the second is involved mainly in the formation of the charge-assisted heterodimeric synthon –B(OH)₂⋯⁻O₂SO₂ ⁻. These aggregates are further connected through N—H⋯O_sulfate interactions, forming a complex three-dimensional hydrogen-bonded network.

Related literature

For related salts, see: Braga et al. (2003 ▶); Kara et al. (2006 ▶); Rogowska et al. (2006 ▶); Melendez et al. (1996 ▶); Plaut et al. (2000 ▶); SeethaLekshmi et al. (2006 ▶). For the use of boronic acids in crystal engineering, see: Aakeröy et al. (2005 ▶); Filthaus et al. (2008 ▶); Fournier et al. (2003 ▶); Pedireddi et al. (2004 ▶); Rodríguez-Cuamatzi et al. (2004a ▶,b ▶, 2005 ▶, 2009 ▶); Shimpi et al. (2007 ▶); Zhang et al. (2007 ▶). For a description of the Cambridge Structural Database, see: Allen (2002 ▶). For hydrogen-bond motifs, see: Bernstein et al. (1995 ▶).

Experimental

Crystal data

2C₆H₉BNO₂ ⁺·SO₄ ²⁻
M _r = 371.96
Monoclinic,
a = 5.3589 (9) Å
b = 15.695 (3) Å
c = 20.489 (3) Å
β = 101.423 (3)°
V = 1689.1 (5) Å³
Z = 4
Mo Kα radiation
μ = 0.24 mm⁻¹
T = 173 K
0.41 × 0.18 × 0.09 mm

Data collection

Bruker SMART APEX CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 1996 ▶) T _min = 0.83, T _max = 1.00
18634 measured reflections
3675 independent reflections
2642 reflections with I > 2σ(I)
R _int = 0.096

Refinement

R[F ² > 2σ(F ²)] = 0.078
wR(F ²) = 0.145
S = 1.12
3675 reflections
256 parameters
10 restraints
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.36 e Å⁻³
Δρ_min = −0.37 e Å⁻³

Data collection: SMART (Bruker, 2000 ▶); cell refinement: SAINT-Plus NT (Bruker, 2001 ▶); data reduction: SAINT-Plus NT; program(s) used to solve structure: SHELXTL-NT (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXTL-NT; molecular graphics: SHELXTL-NT; software used to prepare material for publication: PLATON (Spek, 2009 ▶) and publCIF (Westrip, 2010 ▶).

Supplementary Material

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536810012092/tk2649sup1.cif

e-66-o1035-sup1.cif^{(18.4KB, cif)}

Structure factors: contains datablocks I. DOI: 10.1107/S1600536810012092/tk2649Isup2.hkl

e-66-o1035-Isup2.hkl^{(180.2KB, hkl)}

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Table 1. Hydrogen-bond geometry (Å, °).

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O31—H31′⋯O53ⁱ	0.84 (3)	1.81 (3)	2.653 (4)	175 (3)
O32—H32′⋯O54ⁱ	0.84 (3)	1.96 (3)	2.744 (4)	155 (3)
N1—H1A⋯O54ⁱⁱ	0.87 (4)	2.31 (4)	3.161 (5)	169 (4)
N1—H1C⋯O52ⁱⁱⁱ	0.86 (2)	1.86 (2)	2.718 (4)	176 (5)
O1—H1′⋯O31^iv	0.84 (4)	1.99 (4)	2.803 (4)	163 (4)
N31—H31A⋯O52	0.86 (3)	1.92 (3)	2.787 (4)	179 (3)
N31—H31C⋯O2	0.86 (2)	2.07 (2)	2.874 (4)	156 (3)
O2—H2′⋯O32^v	0.84 (1)	1.99 (2)	2.820 (3)	169 (4)
N1—H1B⋯O51^vi	0.86 (4)	2.13 (4)	2.923 (5)	152 (4)
N1—H1B⋯O54^vi	0.86 (4)	2.37 (4)	3.112 (5)	144 (4)
N31—H31B⋯O53^vii	0.86 (3)	1.90 (3)	2.744 (4)	168 (4)

Open in a new tab

Symmetry codes: (i) Inline graphic ; (ii) ; (iii) ; (iv) ; (v) ; (vi) ; (vii) .

Acknowledgments

This work was supported by the Consejo Nacional de Ciencia y Tecnología (CIAM-59213).

supplementary crystallographic information

Comment

Boronic acids, RB(OH)₂, are capable of forming strong hydrogen bonds with different functional groups such as carboxylic acid and pyridine derivatives (Aakeröy et al., 2005; Pedireddi et al., 2004; Rodríguez-Cuamatzi et al., 2009) and have been employed not only for the formation of neutral homo- and heterodimeric synthons, e.g. RB(OH)₂···(HO)₂BR and RB(OH)₂···HOOCR (Filthaus et al., 2008; Fournier et al., 2003; Rodríguez-Cuamatzi et al., 2004a,b; Shimpi et al., 2007; Zhang et al., 2007), but also for the generation of charge-assisted synthons such as RB(OH)₂···^-OOCR and RB(OH)₂···^-OSCR (Kara et al., 2006; Rodríguez-Cuamatzi et al., 2005; Rogowska et al., 2006; SeethaLekshmi et al., 2006).

A search of the CSD (Allen, 2002; version 5.30) revealed that aside from the above-mentioned adducts with organic and inorganic carboxylate derivatives, there are only two further entries for charged motifs of the composition RB(OH)₂···^-O₂E, in which the anions are sulfate and nitrate, respectively (Braga et al., 2003).

The title compound, (I), represents a further example for the –B(OH)₂···^-O₂SO₂^- heterodimeric synthon.

The asymmetric unit of I contains two independent protonated 3-aminophenylboronic acid (3-apba) molecules and one sulfate anion as counterion (Fig. 1). Due to the presence of a large number of hydrogen-bonding functions (BOH, NH₃⁺ and SO₄^2-) a complex 3D hydrogen bonded network is formed, in which the sulfate counterions play the role of the central building block within the crystal structure. Each sulfate is hydrogen bonded to four neighboring [3-apbaH]⁺entities through a total of five (B)OH···O_sulfate and N—H···O_sulfate interactions, and serves as four-connected node (Fig. 2).

Motif II is formed between the –B(OH)₂ group of one of the two [3-apbaH]⁺ molecules and the sulfate counterion, and corresponds to the charged heterodimeric motif –B(OH)₂···^-O₂SO₂^-[graph set R₂² (8)] (Bernstein et al. 1995). In motif III [R₄⁴ (12)] two sulfate groups are hydrogen bridged by two NH₃⁺ functions. Structurally related hydrogen-bonded rings have been reported previously for secondary ammonium carboxylates (Melendez et al., 1996; Plaut et al., 2000). In motif IV [R₄⁴(12)] three BOH, one sulfate and one NH₃⁺ group are connected through (B)OH···O_sulfate, (B)OH···O_B, N—H···O_sulfate and N—H···O_B hydrogen bonds , while in motif V [R₃³(11)] two BOH, one sulfate and one NH₃⁺ moiety are connected through (B)OH···O_sulfate, (B)OH···O_B and N—H···O_sulfate hydrogen bonds. Motifs II-V give rise to 2D undulated layers (Fig. 2, Table 1), which are connected through three additional N—H···O_sulfate interactions to give an overall 3D hydrogen-bonded network.

Experimental

The title compound is a commercially available product that has been crystallized from methanol. M.p. > 300 °C.