2-Hydr­oxy-3-nitro­benzamide

Abdul Rauf Raza; Muhammad Danish; M Nawaz Tahir; Bushra Nisar; Mohammad S Iqbal

doi:10.1107/S1600536809022843

. 2009 Jun 20;65(Pt 7):o1630. doi: 10.1107/S1600536809022843

2-Hydroxy-3-nitrobenzamide

Abdul Rauf Raza ^a, Muhammad Danish ^a, M Nawaz Tahir ^b,^*, Bushra Nisar ^a, Mohammad S Iqbal ^c

PMCID: PMC2969278 PMID: 21582897

Abstract

The asymmetric unit of title compound, C₇H₆N₂O₄, contains two molecules, one of which has a disordered nitro group with an occupancy ratio of 0.517 (9):0.483 (9) for the O atoms. Both molecules contain an intramolecular O—H⋯O hydrogen bond. In the crystal, both molecules form inversion dimers linked by pairs of N—H⋯O hydrogen bonds, resulting in R ₂ ²(8) ring motifs. The dimers are connected by further N—H⋯O links and weak C—H⋯O interactions, resulting in a layered motif.

Related literature

For related structures, see: Liu & Zhu (2007 ▶); Pertlik (1990 ▶). For graph-set notation, see: Bernstein et al. (1995 ▶).

Experimental

Crystal data

C₇H₆N₂O₄
M _r = 182.14
Triclinic,
a = 3.8390 (2) Å
b = 13.0347 (8) Å
c = 16.0409 (9) Å
α = 98.207 (3)°
β = 95.658 (2)°
γ = 98.365 (3)°
V = 780.16 (8) Å³
Z = 4
Mo Kα radiation
μ = 0.13 mm⁻¹
T = 296 K
0.25 × 0.22 × 0.18 mm

Data collection

Bruker Kappa APEXII CCD diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2005 ▶) T _min = 0.966, T _max = 0.979
15183 measured reflections
3658 independent reflections
1932 reflections with I > 2σ(I)
R _int = 0.039

Refinement

R[F ² > 2σ(F ²)] = 0.048
wR(F ²) = 0.139
S = 1.00
3658 reflections
287 parameters
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.19 e Å⁻³
Δρ_min = −0.18 e Å⁻³

Data collection: APEX2 (Bruker, 2007 ▶); cell refinement: SAINT (Bruker, 2007 ▶); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: ORTEP-3 (Farrugia, 1997 ▶) and PLATON (Spek, 2009 ▶); software used to prepare material for publication: WinGX (Farrugia, 1999 ▶) and PLATON.

Supplementary Material

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536809022843/hb5009sup1.cif

e-65-o1630-sup1.cif^{(19.6KB, cif)}

Structure factors: contains datablocks I. DOI: 10.1107/S1600536809022843/hb5009Isup2.hkl

e-65-o1630-Isup2.hkl^{(175.7KB, 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
O1—H1O⋯O4	0.82	1.77	2.500 (2)	148
N2—H2A⋯O6Aⁱ	0.80 (3)	2.38 (3)	3.142 (5)	161 (3)
N2—H2B⋯O4ⁱⁱ	0.93 (3)	2.03 (3)	2.966 (3)	177 (2)
N4—H4A⋯O8ⁱⁱⁱ	0.87 (3)	2.07 (3)	2.929 (3)	172 (2)
N4—H4B⋯O2^iv	0.91 (3)	2.18 (3)	3.084 (3)	174 (2)
O5—H5O⋯O8	0.82	1.76	2.496 (2)	148
C6—H6⋯O6Aⁱ	0.91 (2)	2.40 (2)	3.285 (6)	163 (2)
C11—H11⋯O7A^v	0.92 (2)	2.41 (2)	3.221 (6)	147 (2)
C11—H11⋯O7A^vi	0.92 (2)	2.55 (2)	2.997 (6)	110.5 (17)
C13—H13⋯O2^iv	0.92 (2)	2.39 (2)	3.289 (3)	165 (2)

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

Acknowledgments

The authors acknowledge the Higher Education Commission, Islamabad, Pakistan, and Bana International, Karachi, Pakistan, for funding the purchase of the diffractometer at GCU, Lahore and for technical support, respectively.

supplementary crystallographic information

Comment

The title compound (I), (Fig. 1), has been prepared as an intermediate for derivatization. The purpose of structure determination was to investigate the amount and position of nitration on the 2-hydroxybenzamide.

The crystal structures of (II) 2-Hydroxybenzamide (Pertlik, 1990) and (III) 2-Hydroxy-3,5-dinitrobenzamide monohydrate (Liu & Zhu, 2007) have been published which contain the common group of hydroxybenzamide as in (I).

The title compound consists of two molecules in the asymmetric unit. The O-atoms of nitro group in one of the molecules are disordered over two sites with occupancy ratio of 0.517 (9):0.483 (9). In both molecules the hydroxy group form intramolecular H-bonding with the O-atom of amide group, thus completing ring motifs R₁¹(6) (Bernstein et al., 1995). The H-atoms of NH₂ groups behave differently. One H-atom forms dimer, whereas the other is used in linkage of the dimers. It is intersting that both molecules form dimers among themselves through the intermolecular H-bonds of N—H···O type with ring motifs R₂²(8). The dimers of both molecules are connected to each other through the same type of intermolecular H-bonding (Fig. 2). The molecules are stabilized in the form of two dimensional polymeric sheets due to intera as well as intermolecular H-bonding (Table 1).

Experimental

A solution of 2-hydroxybenzamide (1.37 g, 0.01 mol) in ethylacetate (EtOAc) (25 ml) was added dropwise to a nitrating mixture of HNO₃ (1.89 g, 0.03 mol) and H₂SO₄ (1.96 g, 0.02 mol) with constant stirring while the temperature was kept below 278 K. Then reaction mixture was stirred at room temperature for 4–5 h. The resulting mixture was refluxed for 1 h, cooled, neutralized with aq. NaHCO₃ (10%) and extracted with EtOAc (3 × 25 ml). The organic layers were combined, dried over anhydrous Na₂SO₄, filtered and concentrated under reduced pressure to afford a reddish brown solid. The column chromatographic purification with 0, 2.5, 5 and 7.5% EtOAc in petrol (0.5 L each) over a silica gel packed column (25.5 cm) afforded brown prisms of (I).