2-[1-(4-Bromo­phen­yl)-2-nitro­eth­yl]hexa­noic acid

Yanpeng Zhang; Can Zhang; Ai-Bao Xia

doi:10.1107/S1600536814006941

. 2014 Apr 5;70(Pt 5):o518. doi: 10.1107/S1600536814006941

2-[1-(4-Bromophenyl)-2-nitroethyl]hexanoic acid

Yanpeng Zhang ^a, Can Zhang ^a, Ai-Bao Xia ^a,^*

PMCID: PMC4011287 PMID: 24860332

Abstract

In the crystal structure of the title compoud, C₁₄H₁₈BrNO₄, molecules are linked by a strong O—H⋯O hydrogen bond and weaker C—H⋯O interactions. The benzene ring makes dihedral angles of 3.67 (3) and 72.63 (3)° with the carboxylic acid group and the nitro group, respectively.

Related literature

For related compounds, see: Wu et al. (2011 ▶); Nayak et al. (2013 ▶); Zhang et al. (2013 ▶); Thirunavukkarasu et al. (2014 ▶). For the asymmetric Michael reaction, which allows for the formation of two asymmetric centres, see: Enders et al. (2002 ▶); Hayashi et al. (2005 ▶); Keller et al. (2013 ▶).

Experimental

Crystal data

C₁₄H₁₈BrNO₄
M _r = 344.20
Triclinic,
a = 7.2825 (11) Å
b = 8.7850 (13) Å
c = 13.026 (2) Å
α = 107.882 (3)°
β = 93.156 (3)°
γ = 101.555 (3)°
V = 770.9 (2) Å³
Z = 2
Mo Kα radiation
μ = 2.68 mm⁻¹
T = 140 K
0.25 × 0.20 × 0.15 mm

Data collection

Bruker APEXII CCD diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2004 ▶) T _min = 0.510, T _max = 0.746
7818 measured reflections
4717 independent reflections
3078 reflections with I > 2σ(I)
R _int = 0.026

Refinement

R[F ² > 2σ(F ²)] = 0.045
wR(F ²) = 0.113
S = 0.99
4717 reflections
182 parameters
H-atom parameters constrained
Δρ_max = 0.77 e Å⁻³
Δρ_min = −0.57 e Å⁻³

Data collection: APEX2 (Bruker, 2004 ▶); cell refinement: SAINT (Bruker, 2004 ▶); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXL2013 (Sheldrick, 2008 ▶); molecular graphics: SHELXTL (Sheldrick, 2008 ▶); software used to prepare material for publication: SHELXTL.

Supplementary Material

Crystal structure: contains datablock(s) General, I. DOI: 10.1107/S1600536814006941/fj2666sup1.cif

e-70-0o518-sup1.cif^{(243.8KB, cif)}

Structure factors: contains datablock(s) I. DOI: 10.1107/S1600536814006941/fj2666Isup2.hkl

e-70-0o518-Isup2.hkl^{(258.7KB, hkl)}

Click here for additional data file.^{(5.5KB, cml)}

Supporting information file. DOI: 10.1107/S1600536814006941/fj2666Isup3.cml

CCDC reference: 994185

Additional supporting information: crystallographic information; 3D view; checkCIF report

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

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C1—H1B⋯O1ⁱ	0.99	2.43	3.410 (3)	172
C1—H1A⋯O2ⁱⁱ	0.99	2.51	3.265 (3)	133
C3—H3⋯O3ⁱⁱⁱ	1.00	2.69	3.679 (3)	169
C8—H8B⋯O2^iv	0.98	2.60	3.501 (4)	153
O3—H3A⋯O4^v	0.84	1.79	2.619 (2)	171

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

Acknowledgments

We thank Professor Jie Sun of the Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, for his help.

supplementary crystallographic information

1. Comment

Michael addition can represent the initiating step of many complex inter- and intramolecular tandem processes. The use of the highly reactive nitroalkene as Michael acceptors opens the way to synthetically very useful C—C and C—X bond-forming reactions and subsequent transformations as is demonstrated by various applications(Enders et al.,2002). The title compound was obtained from the Michael addition of hexanal to (E)-1-bromo-4-(2-nitrovinyl)benzene in our laboratory. The crystal structure of the title compoud has been presented in this paper in Fig. 1. The C2···C3 distance being 1.545 (2) Å. The C1—C2—C3—C4 torsion angle of 59.43 (3)°. The C12···Br distance being 1.894 (2) Å. The C1···N1 distance being 1.492 (2) Å. The H3A—O3—C4 angle of 109.49 (3)°. In the crystal, molecules are linked by weak intermolecular O—H···O interactions. In addition,molecules are also linked by weak H3A—O4, H3A—C4 and H3A– H3A interactions respectively. The dihedral angle between the carboxylic acid group and the benzene ring is 3.67 (3)° and the dihedral angle between the nitro group and the benzene ring is 72.63 (3)°.

2. Experimental

N,N-Dimethylformamide(1.25 ml) was added to the mixture of hexanal (2.5 mmol) with (E)-1-bromo-4-(2-nitrovinyl)benzene(0.5 mmol) in the presence of D,L-proline (0.15 mmol) at room temperature with vigorous stirring. After 1 day, the mixture was extracted with DCM. Solvents were removed under vacuum and the residue was purified by column chromatography on silica gel(eluent:petroleum ether-ether). Then the addition product was oxidized into acid by H₂O₂. Suitable crystals were obtained by slow evaporation of a dichloromethane solution.