Ethyl 4-(2-hydroxy­ethyl­amino)-3-nitro­benzoate

Aisyah Saad Abdul Rahim; Shafida Abd Hamid; Shivanagere Nagojappa Narendra Babu; Wan-Sin Loh; Hoong-Kun Fun

doi:10.1107/S1600536810008147

. 2010 Mar 17;66(Pt 4):o846–o847. doi: 10.1107/S1600536810008147

Ethyl 4-(2-hydroxyethylamino)-3-nitrobenzoate

Aisyah Saad Abdul Rahim ^a,^‡, Shafida Abd Hamid ^b, Shivanagere Nagojappa Narendra Babu ^a, Wan-Sin Loh ^c,^§, Hoong-Kun Fun ^c,^*,^¶

PMCID: PMC2983846 PMID: 21580671

Abstract

In the title compound, C₁₁H₁₄N₂O₅, the molecular structure is stabilized by an intramolecular N—H⋯O hydrogen bond, which generates an S(6) ring motif. The nitro group is twisted slightly from the attached benzene ring, forming a dihedral angle of 5.2 (2)°. In the crystal packing, intermolecular O—H⋯O and C—H⋯O hydrogen bonds link the molecules into a three-dimensional network. The crystal studied was a non-merohedral twin, the refined ratio of the twin components being 0.264 (2):0.736 (2).

Related literature

For background to benzimidazoles, see: Mayer et al. (1998 ▶); Brouillette et al. (1999 ▶); Williams et al. (1995 ▶); Wright (1951 ▶). For reference bond-length data, see: Allen et al. (1987 ▶). For related structures, see: Narendra Babu, Abdul Rahim, Abd Hamid et al. (2009 ▶); Narendra Babu, Abdul Rahim, Osman et al. (2009 ▶). For hydrogen-bond motifs, see: Bernstein et al. (1995 ▶). For the stability of the temperature controller used for the data collection, see: Cosier & Glazer (1986 ▶).

Experimental

Crystal data

C₁₁H₁₄N₂O₅
M _r = 254.24
Monoclinic,
a = 10.6422 (6) Å
b = 14.9954 (9) Å
c = 7.1975 (4) Å
β = 99.607 (2)°
V = 1132.50 (11) Å³
Z = 4
Mo Kα radiation
μ = 0.12 mm⁻¹
T = 100 K
0.43 × 0.13 × 0.03 mm

Data collection

Bruker SMART APEXII CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 209 ▶0) T _min = 0.951, T _max = 0.997
8457 measured reflections
2587 independent reflections
2026 reflections with I > 2σ(I)
R _int = 0.050

Refinement

R[F ² > 2σ(F ²)] = 0.051
wR(F ²) = 0.129
S = 1.04
2587 reflections
173 parameters
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.50 e Å⁻³
Δρ_min = −0.31 e Å⁻³

Data collection: APEX2 (Bruker, 2009 ▶); cell refinement: SAINT (Bruker, 2009 ▶); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL and PLATON (Spek, 2009 ▶).

Supplementary Material

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536810008147/wn2377sup1.cif

e-66-0o846-sup1.cif^{(17.9KB, cif)}

Structure factors: contains datablocks I. DOI: 10.1107/S1600536810008147/wn2377Isup2.hkl

e-66-0o846-Isup2.hkl^{(127.1KB, 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
N2—H2A⋯O2	0.84 (3)	1.99 (3)	2.642 (2)	134 (2)
O5—H5B⋯O3ⁱ	0.83 (3)	2.02 (3)	2.851 (2)	177 (3)
C8—H8A⋯O5ⁱⁱ	0.97	2.51	3.271 (3)	135
C10—H10A⋯O5ⁱⁱⁱ	0.97	2.54	3.267 (3)	132
C10—H10B⋯O1^iv	0.97	2.43	3.168 (3)	133
C11—H11A⋯O2^v	0.97	2.59	3.403 (3)	142

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

Acknowledgments

HKF and WSL thank Universiti Sains Malaysia (USM) for the Research University Golden Goose Grant (1001/PFIZIK/811012). WSL thanks the Malaysian Government and USM for the award of a Research Fellowship. ASAR, SAH and SNNB thank USM for funding the synthetic chemistry work under the University Research Grant (1001/PFARMASI/815026). SNNB acknowledges USM for a post-doctoral research fellowship.

supplementary crystallographic information

Comment

Benzimidazoles serve as a common scaffold used worldwide for various successful drugs (Mayer et al., 1998). Construction of pharmacologically important benzimidazoles could be accessed via nitrobenzoic acid precursors (Brouillette et al., 1999; Williams et al., 1995; Wright, 1951). The title compound was obtained as an intermediate in the synthesis of benzimidazole derivatives; we present here its crystal structure.

In the title compound (Fig. 1), the molecular structure is stabilized by an intramolecular N2—H2A···O2 hydrogen bond which generates an S(6) ring motif (Bernstein et al., 1995). The nitro group is slightly twisted away from the benzene ring, the dihedral angle between N1/O1/O2/C2 and C1–C6 being 5.2 (2)°. The bond lengths (Allen et al., 1987) and angles in the molecule are within normal ranges and are similiar to those in other related structures (Narendra Babu, Abdul Rahim, Abd Hamid et al., 2009; Narendra Babu, Abdul Rahim, Osman et al., 2009).

In the crystal packing (Fig. 2), intermolecular O5—H5B···O3, C8—H8A···O5, C10—H10A···O5, C10—H10B···O1 and C11—H11A···O2 hydrogen bonds (Table 1) link the molecules into a three-dimensional network.

Experimental

The synthesis of the title compound was performed by the dropwise addition of N,N-diisopropyl ethylamine (1.1 mmol) to a stirred solution of ethyl 4-fluoro-3-nitrobenzoate (1.0 mmol) in dry dichloromethane (10.0 ml), followed by ethanolamine (1.1 mmol). The reaction mixture was left stirring overnight at room temperature under an inert atmosphere. Upon completion, the reaction mixture was washed with 10% Na₂CO₃ (3 x 10.0 ml). The combined organic fractions were dried over MgSO₄ and evaporated in vacuo. Recrystallisation with hot hexane gave the title compound as bright yellow crystals, which were found to be suitable for characterisation by X-ray crystallography.