1-(7-Isopropyl-2,5-dimethyl-8-nitro­naphthalen-1-yl)ethanone

Ait Elhad, M.; Benharref, A.; Taourirte, M.; Daran, J.-C.; Oukhrib, A.; Berraho, M.

doi:10.1107/S2414314617003686

organic compounds

IUCrDATA

ISSN: 2414-3146

Volume 2| Part 3| March 2017| x170368

https://doi.org/10.1107/S2414314617003686

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1-(7-Isopropyl-2,5-dimethyl-8-nitronaphthalen-1-yl)ethanone

Mustapha Ait Elhad,^a ^* Ahmed Benharref,^a Moha Taourirte,^b Jean-Claude Daran,^c Abdelouahd Oukhrib ^a and Moha Berraho ^a

^aLaboratoire de Chimie des Substances Naturelles, "Unité Associé au CNRST (URAC16)", Faculté des Sciences Semlalia, BP 2390 Bd My Abdellah, Université Cadi Ayyad, 40000 Marrakech, Morocco, ^bLaboratoire de Chimie Bioorganique et Macromoléculaire, Faculté des Sciences et Techniques, Université Cadi Ayyad, 40000 Marrakech, Morocco, and ^cLaboratoire de Chimie de Coordination, 205 route de Narbonne, 31077 Toulouse Cedex 04, France
^*Correspondence e-mail: aitelhad2017@gmail.com

Edited by H. Stoeckli-Evans, University of Neuchâtel, Switzerland (Received 24 February 2017; accepted 7 March 2017; online 10 March 2017)

The title compound, C₁₇H₁₉NO₃, was synthesized in three steps from a mixture of α-, β- and γ-himachalene, which was isolated from an essential oil of the Atlas cedar (Cedrus atlantica). The dihedral angle between the two rings of the naphthalene moiety is 2.54 (5)°. The nitro group and the acetyl group lie almost normal to the mean plane of the naphthalene moiety, making dihedral angles of 80.29 (13) and 83.01 (15)°, respectively, and are inclined to one another by 13.23 (19)°. There is an intramolecular C—H⋯O hydrogen bond present involving a nitro O atom and the H atom of the methine C atom of the isopropyl group, forming an S(6) ring motif. In the crystal, molecules are linked by pairs of C—H⋯π interactions, forming inversion dimers. There are no other significant intermolecular interactions present.

Keywords: crystal structure; β-himachalene; Atlas cedar; hydrogen bonding.

CCDC reference: 1536512

Structure description

The bicyclic sesquiterpenes α- and β-himachalene are the main constituents of the essential oil of the Atlas cedar (Cedrus atlantica) (Benharref et al., 2015 ; Loubidi et al., 2014 ). The reactivity of these sesquiterpenes and their derivatives have been studied extensively by our team in order to prepare new products having biological proprieties (El Haib et al., 2011 ; Benharref et al., 2013 , 2015, 2016 ; Zaki et al., 2014 ). Indeed, these compounds have been tested, using the food poisoning technique, for their potential antifungal activity against the phytopathogen Botrytis cinerea (Daoubi et al., 2004 ). Herein, we report on the crystal structure of the title compound.

The molecular structure of the title compound is illustrated in Fig. 1. The naphthalene ring system is approximately planar, with the dihedral angle between the two benzene rings being 2.54 (5)°. The nitro group (N1/O21/O22) and the acteyl group (C11/O11/C12) lie almost normal to the mean plane of the naphthalene moiety, making dihedral angles of 80.29 (13) and 83.01 (15)°, respectively, and are inclined to one another by 13.23 (19)°. There is an intramolecular C—H⋯O hydrogen bond present involving a nitro O atom, O21, and the H atom of atom C13 of the isopropyl group, forming an S(6) ring motif (Table 1 and Fig. 1).

Table 1
Hydrogen-bond geometry (Å, °)

Cg is the centroid of the C1/C6–C10 ring.

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C13—H13⋯O21	1.00	2.49	3.2063 (16)	128
C12—H12B⋯Cgⁱ	0.98	2.79	3.562 (2)	136
Symmetry code: (i) -x+1, -y+1, -z+1.

Figure 1
The molecular structure of the title compound, with the atom labelling. Displacement ellipsoids are drawn at the 30% probability level. The intramolecular C—H⋯O hydrogen bond is shown as a dashed line (see Table 1

In the crystal, molecules are linked by pairs of C—H⋯π interactions, forming inversion dimers (Table 1 and Fig. 2). There are no other significant intermolecular interactions present.

Figure 2
A view along the b axis of the crystal packing of the title compound. The intramolecular hydrogen bonds are shown as a dashed line and the C—H⋯π interactions as blue arrows (see Table 1

; H atoms involved are shown as grey balls).

Synthesis and crystallization

In a 250 ml reactor equipped with a magnetic stirrer and a dropping funnel, were introduced 60 ml of dichloromethane, 3 ml of nitric acid and 5 ml of concentrated sulfuric acid. After cooling, 6 g (30 mmol) of 1,6-dimethyl-4-isopropylnaphtalene (Benharref et al., 2016) dissolved in 30 ml of dichloromethane were added dropwise through a dropping funnel. The reaction mixture was stirred for 4 h, then 50 ml of ice–water were added and the mixture was extracted with dichloromethane. The organic layers were combined, washed with water (5 × 40 ml) and dried over sodium sulfate and then concentrated in vacuo. 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 2-isopropyl-4,7-dimethyl-1-nitronaphthalene. 3 g (10 mmol) of the latter compound were treated with two equivalents of acetyl chloride in the presence of 2 equivalents of aluminium chloride in 50 ml of dichloromethane with stirring at room temperature for 6 h. After addition of 30 ml of water, the reaction mixture was extracted with dichloromethane (3 × 20 ml). The organic phases were combined, dried over sodium sulfate and then concentrated in vacuo. Chromatography on a silica gel column with hexane–ethyl acetate (97:3) as eluent of the residue gave the title compound (yield 1.5 g, 6 mmol; 60%). It was recrystallized from cyclohexane to obtain colourless plate-like crystals.

Refinement

Crystal data, data collection and structure refinement details are summarized in Table 2.

Table 2
Experimental details

Crystal data
Chemical formula	C₁₇H₁₉NO₃
M_r	285.33
Crystal system, space group	Monoclinic, P2₁/n
Temperature (K)	173
a, b, c (Å)	10.8570 (5), 9.0549 (4), 14.9550 (7)
β (°)	91.006 (4)
V (Å³)	1469.99 (12)
Z	4
Radiation type	Mo Kα
μ (mm⁻¹)	0.09
Crystal size (mm)	0.50 × 0.45 × 0.15

Data collection
Diffractometer	Bruker X8 APEX
Absorption correction	Multi-scan (SADABS; Bruker, 2009 )
T_min, T_max	0.811, 1.0
No. of measured, independent and observed [I > 2σ(I)] reflections	15373, 3005, 2548
R_int	0.024
(sin θ/λ)_max (Å⁻¹)	0.625

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.037, 0.103, 1.05
No. of reflections	3005
No. of parameters	194
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.23, −0.19
Computer programs: APEX2 and SAINT (Bruker, 2009), SHELXS2014 (Sheldrick, 2008 ), SHELXL2014 (Sheldrick, 2015 ), ORTEP-3 for Windows (Farrugia, 2012 ), Mercury (Macrae et al., 2008 ) and publCIF (Westrip, 2010 ).

Structural data

CCDC reference: 1536512

Crystal structure: contains datablocks I, block. DOI: https://doi.org/10.1107/S2414314617003686/su4136sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2414314617003686/su4136Isup2.hkl

Supporting information file. DOI: https://doi.org/10.1107/S2414314617003686/su4136Isup3.cml

checkCIF report

Computing details top

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); program(s) used to solve structure: SHELXS2014 (Sheldrick, 2008); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012) and Mercury (Macrae et al., 2008); software used to prepare material for publication: publCIF (Westrip, 2010).

1-(7-Isopropyl-2,5-dimethyl-8-nitronaphthalen-1-yl)ethanone top

Crystal data top

C₁₇H₁₉NO₃	F(000) = 608
M_r = 285.33	D_x = 1.289 Mg m⁻³
Monoclinic, P2₁/n	Mo Kα radiation, λ = 0.71073 Å
a = 10.8570 (5) Å	Cell parameters from 3005 reflections
b = 9.0549 (4) Å	θ = 3.2–26.4°
c = 14.9550 (7) Å	µ = 0.09 mm⁻¹
β = 91.006 (4)°	T = 173 K
V = 1469.99 (12) Å³	Plate, colourless
Z = 4	0.50 × 0.45 × 0.15 mm

Data collection top

Bruker X8 APEX diffractometer	3005 independent reflections
Radiation source: fine-focus sealed X-ray tube, Enhance (Mo) X-ray Source	2548 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.024
φ and ω scans	θ_max = 26.4°, θ_min = 3.2°
Absorption correction: multi-scan (SADABS; Bruker, 2009)	h = −13→13
T_min = 0.811, T_max = 1.0	k = −11→11
15373 measured reflections	l = −18→18

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F² > 2σ(F²)] = 0.037	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.103	H-atom parameters constrained
S = 1.05	w = 1/[σ²(F_o²) + (0.0501P)² + 0.4513P] where P = (F_o² + 2F_c²)/3
3005 reflections	(Δ/σ)_max < 0.001
194 parameters	Δρ_max = 0.23 e Å⁻³
0 restraints	Δρ_min = −0.19 e Å⁻³

Special details top

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq	Occ. (<1)
O11	0.18310 (9)	0.30707 (12)	0.51378 (7)	0.0414 (3)
O21	0.31296 (9)	0.05669 (11)	0.42478 (7)	0.0397 (3)
O22	0.46037 (9)	0.16464 (11)	0.49836 (6)	0.0387 (3)
N1	0.39471 (10)	0.14874 (11)	0.43175 (7)	0.0256 (2)
C1	0.37364 (10)	0.39248 (13)	0.35320 (7)	0.0198 (2)
C2	0.41980 (10)	0.24493 (13)	0.35431 (8)	0.0210 (3)
C3	0.49041 (11)	0.18396 (13)	0.28881 (8)	0.0232 (3)
C4	0.51874 (11)	0.27486 (14)	0.21482 (8)	0.0246 (3)
H4	0.5702	0.2364	0.1696	0.030*
C5	0.47494 (10)	0.41555 (13)	0.20598 (8)	0.0224 (3)
C6	0.40118 (10)	0.47684 (13)	0.27500 (8)	0.0207 (3)
C7	0.35676 (11)	0.62331 (14)	0.26845 (8)	0.0246 (3)
H7	0.3725	0.6791	0.2161	0.030*
C8	0.29211 (12)	0.68594 (14)	0.33537 (9)	0.0278 (3)
H8	0.2649	0.7852	0.3294	0.033*
C9	0.26449 (11)	0.60652 (14)	0.41374 (8)	0.0261 (3)
C10	0.30488 (10)	0.46193 (13)	0.42254 (8)	0.0219 (3)
C11	0.27223 (11)	0.38588 (14)	0.50948 (8)	0.0258 (3)
C12	0.35266 (14)	0.41952 (18)	0.58950 (9)	0.0386 (3)
H12A	0.3426	0.5234	0.6063	0.058*
H12B	0.4389	0.4010	0.5749	0.058*
H12C	0.3290	0.3562	0.6395	0.058*
C13	0.54302 (12)	0.02859 (14)	0.29434 (9)	0.0275 (3)
H13	0.4955	−0.0276	0.3398	0.033*
C14	0.67745 (13)	0.03500 (17)	0.32595 (11)	0.0409 (4)
H14A	0.7243	0.0975	0.2852	0.061*
H14B	0.7122	−0.0649	0.3265	0.061*
H14C	0.6821	0.0765	0.3864	0.061*
C15	0.53056 (15)	−0.05265 (16)	0.20523 (10)	0.0393 (3)
H15A	0.4438	−0.0545	0.1861	0.059*
H15B	0.5608	−0.1540	0.2123	0.059*
H32B	0.5791	−0.0015	0.1601	0.059*
C16	0.50429 (12)	0.50419 (15)	0.12365 (8)	0.0284 (3)
H16A	0.5556	0.4450	0.0840	0.043*
H16B	0.5488	0.5941	0.1412	0.043*
H16C	0.4275	0.5310	0.0922	0.043*
C17	0.18716 (14)	0.68217 (17)	0.48318 (10)	0.0384 (3)
H17A	0.1689	0.7834	0.4639	0.058*	0.5
H17B	0.1099	0.6277	0.4903	0.058*	0.5
H17C	0.2325	0.6845	0.5404	0.058*	0.5
H17D	0.1720	0.6137	0.5325	0.058*	0.5
H17E	0.2309	0.7693	0.5061	0.058*	0.5
H17F	0.1084	0.7126	0.4560	0.058*	0.5

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O11	0.0335 (5)	0.0469 (6)	0.0440 (6)	−0.0094 (5)	0.0081 (4)	0.0083 (5)
O21	0.0422 (6)	0.0355 (5)	0.0417 (6)	−0.0116 (4)	0.0097 (4)	0.0077 (4)
O22	0.0480 (6)	0.0449 (6)	0.0229 (5)	0.0056 (5)	−0.0055 (4)	0.0064 (4)
N1	0.0289 (5)	0.0240 (5)	0.0240 (6)	0.0035 (4)	0.0048 (4)	0.0041 (4)
C1	0.0177 (5)	0.0231 (6)	0.0186 (6)	−0.0035 (4)	−0.0015 (4)	0.0003 (5)
C2	0.0206 (5)	0.0237 (6)	0.0186 (6)	−0.0029 (4)	0.0003 (4)	0.0036 (5)
C3	0.0220 (5)	0.0241 (6)	0.0236 (6)	−0.0005 (5)	0.0017 (4)	0.0010 (5)
C4	0.0240 (6)	0.0284 (6)	0.0215 (6)	−0.0003 (5)	0.0058 (4)	0.0001 (5)
C5	0.0211 (6)	0.0270 (6)	0.0192 (6)	−0.0043 (5)	0.0005 (4)	0.0024 (5)
C6	0.0194 (5)	0.0238 (6)	0.0188 (6)	−0.0033 (4)	−0.0022 (4)	0.0012 (5)
C7	0.0246 (6)	0.0252 (6)	0.0239 (6)	−0.0022 (5)	−0.0015 (5)	0.0052 (5)
C8	0.0300 (6)	0.0233 (6)	0.0302 (7)	0.0025 (5)	−0.0020 (5)	0.0017 (5)
C9	0.0260 (6)	0.0278 (6)	0.0245 (6)	0.0006 (5)	−0.0003 (5)	−0.0022 (5)
C10	0.0199 (5)	0.0263 (6)	0.0196 (6)	−0.0021 (5)	−0.0010 (4)	−0.0003 (5)
C11	0.0249 (6)	0.0272 (6)	0.0255 (7)	0.0033 (5)	0.0073 (5)	0.0001 (5)
C12	0.0464 (8)	0.0473 (9)	0.0220 (7)	0.0026 (7)	0.0002 (6)	0.0008 (6)
C13	0.0295 (6)	0.0253 (6)	0.0280 (7)	0.0028 (5)	0.0070 (5)	0.0036 (5)
C14	0.0346 (7)	0.0393 (8)	0.0486 (9)	0.0084 (6)	−0.0028 (6)	0.0014 (7)
C15	0.0502 (9)	0.0266 (7)	0.0411 (8)	0.0005 (6)	0.0036 (7)	−0.0030 (6)
C16	0.0317 (6)	0.0321 (7)	0.0215 (6)	−0.0009 (5)	0.0050 (5)	0.0052 (5)
C17	0.0482 (8)	0.0353 (8)	0.0320 (8)	0.0107 (6)	0.0074 (6)	−0.0030 (6)

Geometric parameters (Å, º) top

O11—C11	1.2050 (16)	C11—C12	1.5002 (19)
O21—N1	1.2206 (14)	C12—H12A	0.9800
O22—N1	1.2232 (14)	C12—H12B	0.9800
N1—C2	1.4783 (15)	C12—H12C	0.9800
C1—C2	1.4269 (16)	C13—C15	1.5261 (19)
C1—C6	1.4327 (16)	C13—C14	1.5273 (19)
C1—C10	1.4337 (16)	C13—H13	1.0000
C2—C3	1.3706 (17)	C14—H14A	0.9800
C3—C4	1.4172 (17)	C14—H14B	0.9800
C3—C13	1.5201 (17)	C14—H14C	0.9800
C4—C5	1.3654 (18)	C15—H15A	0.9800
C4—H4	0.9500	C15—H15B	0.9800
C5—C6	1.4295 (17)	C15—H32B	0.9800
C5—C16	1.5085 (17)	C16—H16A	0.9800
C6—C7	1.4141 (17)	C16—H16B	0.9800
C7—C8	1.3567 (18)	C16—H16C	0.9800
C7—H7	0.9500	C17—H17A	0.9800
C8—C9	1.4118 (18)	C17—H17B	0.9800
C8—H8	0.9500	C17—H17C	0.9800
C9—C10	1.3862 (18)	C17—H17D	0.9800
C9—C17	1.5110 (18)	C17—H17E	0.9800
C10—C11	1.5187 (17)	C17—H17F	0.9800

O21—N1—O22	124.23 (11)	C15—C13—C14	110.99 (12)
O21—N1—C2	118.63 (10)	C3—C13—H13	108.1
O22—N1—C2	117.12 (10)	C15—C13—H13	108.1
C2—C1—C6	115.50 (10)	C14—C13—H13	108.1
C2—C1—C10	126.12 (10)	C13—C14—H14A	109.5
C6—C1—C10	118.38 (10)	C13—C14—H14B	109.5
C3—C2—C1	124.71 (11)	H14A—C14—H14B	109.5
C3—C2—N1	115.83 (10)	C13—C14—H14C	109.5
C1—C2—N1	119.43 (10)	H14A—C14—H14C	109.5
C2—C3—C4	117.12 (11)	H14B—C14—H14C	109.5
C2—C3—C13	123.25 (11)	C13—C15—H15A	109.5
C4—C3—C13	119.57 (11)	C13—C15—H15B	109.5
C5—C4—C3	122.51 (11)	H15A—C15—H15B	109.5
C5—C4—H4	118.7	C13—C15—H32B	109.5
C3—C4—H4	118.7	H15A—C15—H32B	109.5
C4—C5—C6	119.40 (11)	H15B—C15—H32B	109.5
C4—C5—C16	119.81 (11)	C5—C16—H16A	109.5
C6—C5—C16	120.78 (11)	C5—C16—H16B	109.5
C7—C6—C5	120.58 (11)	H16A—C16—H16B	109.5
C7—C6—C1	118.74 (11)	C5—C16—H16C	109.5
C5—C6—C1	120.66 (11)	H16A—C16—H16C	109.5
C8—C7—C6	121.41 (11)	H16B—C16—H16C	109.5
C8—C7—H7	119.3	C9—C17—H17A	109.5
C6—C7—H7	119.3	C9—C17—H17B	109.5
C7—C8—C9	121.31 (12)	H17A—C17—H17B	109.5
C7—C8—H8	119.3	C9—C17—H17C	109.5
C9—C8—H8	119.3	H17A—C17—H17C	109.5
C10—C9—C8	119.24 (11)	H17B—C17—H17C	109.5
C10—C9—C17	122.80 (12)	C9—C17—H17D	109.5
C8—C9—C17	117.92 (12)	H17A—C17—H17D	141.1
C9—C10—C1	120.90 (11)	H17B—C17—H17D	56.3
C9—C10—C11	115.55 (11)	H17C—C17—H17D	56.3
C1—C10—C11	123.55 (10)	C9—C17—H17E	109.5
O11—C11—C12	122.30 (12)	H17A—C17—H17E	56.3
O11—C11—C10	120.93 (12)	H17B—C17—H17E	141.1
C12—C11—C10	116.72 (11)	H17C—C17—H17E	56.3
C11—C12—H12A	109.5	H17D—C17—H17E	109.5
C11—C12—H12B	109.5	C9—C17—H17F	109.5
H12A—C12—H12B	109.5	H17A—C17—H17F	56.3
C11—C12—H12C	109.5	H17B—C17—H17F	56.3
H12A—C12—H12C	109.5	H17C—C17—H17F	141.1
H12B—C12—H12C	109.5	H17D—C17—H17F	109.5
C3—C13—C15	111.78 (11)	H17E—C17—H17F	109.5
C3—C13—C14	109.74 (11)

Hydrogen-bond geometry (Å, º) top

Cg is the centroid of the C1/C6–C10 ring.

D—H···A	D—H	H···A	D···A	D—H···A
C13—H13···O21	1.00	2.49	3.2063 (16)	128
C12—H12B···Cgⁱ	0.98	2.79	3.562 (2)	136

Symmetry code: (i) −x+1, −y+1, −z+1.

Acknowledgements

The authors thank the Laboratoire de Chimie de Coordination, UPR-CNRS 8241 Toulouse, for the X-ray measurements.

References

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