Crystal structure of 1-isopropyl-4,7-dimethyl-3-nitro­naphthalene

Ahmed Benharref; Jamal Elkarroumi; Lahcen El Ammari; Mohamed Saadi; Moha Berraho

doi:10.1107/S2056989015014395

. 2015 Aug 15;71(Pt 9):o659–o660. doi: 10.1107/S2056989015014395

Crystal structure of 1-isopropyl-4,7-dimethyl-3-nitronaphthalene

Ahmed Benharref ^a, Jamal Elkarroumi ^a, Lahcen El Ammari ^b, Mohamed Saadi ^b, Moha Berraho ^a,^*

PMCID: PMC4555421 PMID: 26396890

Abstract

The title compound, C₁₅H₁₇NO₂, was synthesized from a mixture of α-himachalene (2-methylene-6,6,9-trimethylbicyclo[5.4.0^1,7]undec-8-ene) and β-himachalene (2,6,6,9-tetramethylbicyclo[5.4.0^1,7]undeca-1,8-diene), which were isolated from an oil of the Atlas cedar (Cedrus Atlantica). The naphthalene ring system makes dihedral angles of 68.6 (2) and 44.3 (2)°, respectively, with its attached isopropyl C/C/C plane and the nitro group. In the crystal, molecules held together by a C—H⋯O interaction, forming a chain along [-101].

Keywords: crystal structure, essential oil of the Atlas cedar, nitro-naphthalene, C—H⋯O interaction

Related literature

For the main constituents of the essential oil of the Atlas cedar, see: El Haib et al. (2011 ▸); Loubidi et al. (2014 ▸). For the reactivity of these sesquiterpenes and their derivatives, see: Oukhrib et al. (2013 ▸); Zaki et al. (2014 ▸); Benharref et al. (2015 ▸). For antifungal activity of these sesquiterpenes and derivatives, see: Daoubi et al. (2004 ▸).

Experimental

Crystal data

C₁₅H₁₇NO₂
M _r = 243.30
Monoclinic,
a = 9.7637 (7) Å
b = 12.6508 (9) Å
c = 11.6162 (8) Å
β = 113.897 (2)°
V = 1311.82 (16) Å³
Z = 4
Mo Kα radiation
μ = 0.08 mm⁻¹
T = 296 K
0.45 × 0.35 × 0.30 mm

Data collection

Bruker APEXII CCD diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2009 ▸) T _min = 0.652, T _max = 0.746
21437 measured reflections
2686 independent reflections
2164 reflections with I > 2σ(I)
R _int = 0.027

Refinement

R[F ² > 2σ(F ²)] = 0.047
wR(F ²) = 0.147
S = 1.07
2686 reflections
167 parameters
H-atom parameters constrained
Δρ_max = 0.22 e Å⁻³
Δρ_min = −0.17 e Å⁻³

Data collection: APEX2 (Bruker, 2009 ▸); cell refinement: SAINT (Bruker, 2009 ▸); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ▸); program(s) used to refine structure: SHELXL2013 (Sheldrick, 2015 ▸); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012 ▸); software used to prepare material for publication: WinGX (Farrugia, 2012 ▸).

Supplementary Material

Crystal structure: contains datablock(s) I. DOI: 10.1107/S2056989015014395/is5409sup1.cif

e-71-0o659-sup1.cif^{(923.5KB, cif)}

Structure factors: contains datablock(s) I. DOI: 10.1107/S2056989015014395/is5409Isup2.hkl

e-71-0o659-Isup2.hkl^{(215KB, hkl)}

Click here for additional data file.^{(5.1KB, cml)}

Supporting information file. DOI: 10.1107/S2056989015014395/is5409Isup3.cml

Click here for additional data file.^{(1.3MB, tif)}

. DOI: 10.1107/S2056989015014395/is5409fig1.tif

Molecular structure of the title compound with the atom-labelling scheme. Displacement ellipsoids are drawn at the 30% probability level. H atoms are represented as small spheres of arbitrary radii.

Click here for additional data file.^{(2.7MB, tif)}

ac . DOI: 10.1107/S2056989015014395/is5409fig2.tif

Partial packing view showing the C—H⋯O interactions (dashed lines) and the formation of a chain along the ac diagonal.

CCDC reference: 1415866

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

Table 1. Hydrogen-bond geometry (, ).

DHA	DH	HA	D A	DHA
C9H9O2ⁱ	0.93	2.60	3.4823(18)	159

Open in a new tab

Symmetry code: (i) Inline graphic .

Acknowledgments

The authors thank the Unit of Support for Technical and Scientific Research (UATRS, CNRST) for the X-ray measurements and Mohammed V University, Rabat, Morocco, for financial support.

supplementary crystallographic information

S1. Comment

The bicyclic sesquiterpenes, α- and β-himachalene, are the main constituents of the essential oil of the Atlas cedar (Cedrus Atlantica) (El Haib et al., 2011; Loubidi et al., 2014). The reactivity of these sesquiterpenes and its derivatives has been studied extensively by our team in order to prepare new products having biological proprieties (Oukhrib et al., 2013; Zaki et al., 2014; Benharref et al., 2015). Indeed, these compounds were tested, using the food poisoning technique, for their potential antifungal activity against the phytopathogen Botrytis cinerea (Daoubi et al., 2004).

The catalytic dehydrogenation of the mixture of α- and β-himachalene by 5% of palladium on carbon (10%) gives, with good yield, the mixture of arylhimachalene and 1-isopropyl- 4,7-dimethylnaphthalene with respective proportions of 85/15. Treatment of the 1-isopropyl-4,7-dimethylnaphthalene by a mixture of nitric acid and sulfuric acid, gives the title compound with a yield of 70%. The structure of this new product was confirmed by its crystal structure (Fig. 1). Molecules are linked by a C9—H9···O2 contact (Table 1), forming a chain along [101] (Fig. 2).

S2. Experimental

In a reactor of 250 ml equipped with a magnetic stirrer and a dropping funnel, we introduced 60 ml of dichloromethane, 3 ml of nitric acid and 5 ml of concentrated sulfuric acid. After cooling, added dropwise through the dropping funnel 6 g (30 mmol) of 1-isopropyl-4,7-dimethylnaphthalene dissolved in 30 ml of dichloromethane. The reaction mixture was stirred for 4 h, then added 50 ml of water ice and extracted with dichloromethane. The organic layers were combined, washed five times with 40 ml with water and dried over sodium sulfate and then concentrated under vacuum. The residue was subjected to chromatography on a column of silica gel with hexane-ethyl acetate (98/2) as eluent, to obtain 5 g (20 mmol) of the title compound which was recrystallized in hexane.