3-[2-(3-Methyl­quinoxalin-2-yl­oxy)eth­yl]-1,3-oxazolidin-2-one

Ahoya, C.A.; Bouhfid, R.; Daouda, B.; Essassi, E.M.; El Ammari, L.

doi:10.1107/S1600536810012687

organic compounds

CRYSTALLOGRAPHIC
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ISSN: 2056-9890

Volume 66| Part 5| May 2010| Page o1050

https://doi.org/10.1107/S1600536810012687

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3-[2-(3-Methylquinoxalin-2-yloxy)ethyl]-1,3-oxazolidin-2-one

Caleb Anothane Ahoya,^a Rachid Bouhfid,^b Ballo Daouda,^a El Mokhtar Essassi ^a ^*‡ and Lahcen El Ammari ^c

^aLaboratoire de Chimie Organique Hétérocyclique, Pôle de Compétences, Pharmacochimie, Avenue Ibn Battouta, BP 1014, Faculté des Sciences, Université Mohammed V-Agdal, Rabat, Morocco, ^bInstitute of Nanomaterial and Nanotechnology, Avenue Armée Royale, Rabat, Morocco, and ^cLaboratoire de Chimie du Solide Appliquée, Faculté des Sciences, Université Mohammed V-Agdal, Avenue Ibn Battouta, BP 1014, Rabat, Morocco
^*Correspondence e-mail: emessassi@yahoo.fr

(Received 27 March 2010; accepted 5 April 2010; online 10 April 2010)

Two isomers were isolated during the reaction between 3-methylquinoxalin-2-one and bis(2-chloroethyl)amine hydrochloride. The crystal structure of one isomer has already been reported [Caleb, Bouhfid, Essassi & El Ammari (2009). Acta Cryst. E65, o2024–o2025], while that of the second isomer is the subject of this work. The title compound, C₁₄H₁₅N₃O₃, has a new structure containing oxazolidine and quinoxaline rings linked by an ethoxy group. The main difference between the two isomers is the position of the oxazolidine group with respect to the quinoxaline system. The dihedral angle between the fused planar rings and the oxazolidin-2-one ring is 41.63 (8)° in the title molecule.

Related literature

For the biological activity of 3-[2-(3-methyl-1,2-dihydroquinoxalin-2-yloxy)ethyl]oxazolidin-2-one, see: Madhusudhan et al. (2004 ); Soad et al. (2006 ); Sriharsha & Shashikanth (2006 ); Menoret et al. (2009 ); Wilhelmsson et al. (2008 ). For the structure of the isomer of the title compound, see: Caleb et al. (2009 ). For related structures, see: Doubia et al. (2007 ); Mamedov et al. (2007 ); Aschwanden et al.(1976 )

Experimental

Crystal data

C₁₄H₁₅N₃O₃
M_r = 273.29
Triclinic, $[P \overline 1]$
a = 6.9936 (3) Å
b = 7.6916 (3) Å
c = 13.3709 (6) Å
α = 86.649 (2)°
β = 77.044 (2)°
γ = 71.141 (2)°
V = 663.23 (5) Å³
Z = 2
Mo Kα radiation
μ = 0.10 mm⁻¹
T = 296 K
0.41 × 0.33 × 0.20 mm

Data collection

Bruker X8 APEXII CCD area-detector diffractometer
15358 measured reflections
3030 independent reflections
2358 reflections with I > 2σ(I)
R_int = 0.023

Refinement

R[F² > 2σ(F²)] = 0.040
wR(F²) = 0.121
S = 1.06
3030 reflections
198 parameters
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.21 e Å⁻³
Δρ_min = −0.17 e Å⁻³

Data collection: APEX2 (Bruker, 2005 ); cell refinement: APEX2; data reduction: APEX2; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia,1997 ) and PLATON (Spek, 2009 ); software used to prepare material for publication: WinGX (Farrugia, 1999 ).

Supporting information

Crystal structure: contains datablocks global, I. DOI: https://doi.org/10.1107/S1600536810012687/dn2552sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536810012687/dn2552Isup2.hkl

checkCIF report

Comment top

Oxazolidin-2-ones and quinoxalines are subjets of numerous articles in scientific journals concerning the development of new molecules as drug candidates such as antibacterials (Madhusudhan et al. 2004); (Sriharsha & Shashikanth, 2006), anti-viral (Wilhelmsson, et al. 2008), anti-tumor (Soad et al.2006),and anti-inflammatory (Menoret et al. 2009). Our investigation is intended to increase the biological activity of such molecules. During the synthesis, two isomers were isolated, and the structure of isomer 1 has already been published (Caleb et al. 2009) while that of ismer 2 is the subject of the present work.

The structure of the 3-(2-(3-methyl-1,2-dihydro-quinoxalin-2-yloxy)ethoxy) oxazolidin-2-one molecule is also built up from two fused six-membered rings linked to a five-membered ring (oxazolidin-2-one) by an ethoxy group, as shown in Fig.1. It would be interesting to compare the crystal structures of both isomers of this compound (scheme 1). Actually, the geometric parameters (bond lenghths and angles) of the two isomers are very similar to those observed in other heterocyclic structures (Aschwanden et al., 1976; Doubia et al., 2007; Mamedov et al., 2007). However, the main difference between the two isomers is the position of the oxazolidine group with respect to the quinoxalin. Moreover, the dihedral angle between the fused six-membered rings and the five cycles measuring 20.04 (9)° in the isomer 1 instead of 41.63 (8)° in the isomer 2.

Related literature top

For the biological activity of 3-[2-(3-methyl-1,2-dihydroquinoxalin-2-yloxy)ethyl]oxazolidin-2-one, see: Madhusudhan et al. (2004); Soad et al. (2006); Sriharsha & Shashikanth (2006); Menoret et al. (2009); Wilhelmsson et al. (2008). For the structure of the isomer of the title compound, see: Caleb et al. (2009). For related structures, see: Doubia et al. (2007); Mamedov et al. (2007); Aschwanden et al.(1976).

Experimental top

In a 100 ml flask, is reacted 0.0125 moles of quinoxalin-2-one with 2.66 moles of dichloroethylamine hydrochloride in 40 ml of dimethyl formamide in presence of 2.87 moles of potassium carbonate and a few milligrams of tetran-butyl ammonium bromide. The mixture was brought to reflux in a sand bath, magnetic stirring and the reaction progress was monitored by thin layer chromatography. After evaporation of solvent under reduced pressure, the residue obtained is chromatographed on silica column (hexane / acetate: 4 / 6). Thus we have isolated two compounds. Recrystallization occurred in the same eluent. This compound was obtained in 38% and his melting point is 169°C.

Structure description top

For the biological activity of 3-[2-(3-methyl-1,2-dihydroquinoxalin-2-yloxy)ethyl]oxazolidin-2-one, see: Madhusudhan et al. (2004); Soad et al. (2006); Sriharsha & Shashikanth (2006); Menoret et al. (2009); Wilhelmsson et al. (2008). For the structure of the isomer of the title compound, see: Caleb et al. (2009). For related structures, see: Doubia et al. (2007); Mamedov et al. (2007); Aschwanden et al.(1976).

Computing details top

Data collection: APEX2 (Bruker, 2005); cell refinement: APEX2 (Bruker, 2005); data reduction: APEX2 (Bruker, 2005); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia,1997) and PLATON (Spek, 2009); software used to prepare material for publication: WinGX (Farrugia, 1999).

Figures top

	Fig. 1. : Molecular structure of the title compound with the atom-labelling scheme. Displacement ellipsoids are drawn at the 50% probability level. H atoms are represented as small circles.
	Fig. 2. The structures of the two isomers.

3-[2-(3-Methylquinoxalin-2-yloxy)ethyl]-1,3-oxazolidin-2-one top

Crystal data top

C₁₄H₁₅N₃O₃	Z = 2
M_r = 273.29	F(000) = 288
Triclinic, P1	D_x = 1.368 Mg m⁻³
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 6.9936 (3) Å	Cell parameters from 15358 reflections
b = 7.6916 (3) Å	θ = 2.8–27.5°
c = 13.3709 (6) Å	µ = 0.10 mm⁻¹
α = 86.649 (2)°	T = 296 K
β = 77.044 (2)°	Prism, colourless
γ = 71.141 (2)°	0.41 × 0.33 × 0.20 mm
V = 663.23 (5) Å³

Data collection top

Bruker X8 APEXII CCD area-detector diffractometer	2358 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	R_int = 0.023
Graphite monochromator	θ_max = 27.5°, θ_min = 2.8°
φ and ω scans	h = −9→9
15358 measured reflections	k = −9→9
3030 independent reflections	l = −17→17

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)] = 0.040	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.121	H atoms treated by a mixture of independent and constrained refinement
S = 1.06	w = 1/[σ²(F_o²) + (0.0643P)² + 0.0716P] where P = (F_o² + 2F_c²)/3
3030 reflections	(Δ/σ)_max < 0.001
198 parameters	Δρ_max = 0.21 e Å⁻³
0 restraints	Δρ_min = −0.17 e Å⁻³

Crystal data top

C₁₄H₁₅N₃O₃	γ = 71.141 (2)°
M_r = 273.29	V = 663.23 (5) Å³
Triclinic, P1	Z = 2
a = 6.9936 (3) Å	Mo Kα radiation
b = 7.6916 (3) Å	µ = 0.10 mm⁻¹
c = 13.3709 (6) Å	T = 296 K
α = 86.649 (2)°	0.41 × 0.33 × 0.20 mm
β = 77.044 (2)°

Data collection top

Bruker X8 APEXII CCD area-detector diffractometer	2358 reflections with I > 2σ(I)
15358 measured reflections	R_int = 0.023
3030 independent reflections

Refinement top

R[F² > 2σ(F²)] = 0.040	0 restraints
wR(F²) = 0.121	H atoms treated by a mixture of independent and constrained refinement
S = 1.06	Δρ_max = 0.21 e Å⁻³
3030 reflections	Δρ_min = −0.17 e Å⁻³
198 parameters

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.

Refinement. Refinement of F² against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F², conventional R-factors R are based on F, with F set to zero for negative F². The threshold expression of F² > σ(F²) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F² are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger.

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

	x	y	z	U_iso*/U_eq
C1	0.31122 (17)	0.72867 (15)	0.95763 (8)	0.0378 (3)
C2	0.08813 (17)	0.80823 (15)	1.11146 (8)	0.0382 (3)
C3	−0.11007 (19)	0.83829 (18)	1.17492 (10)	0.0470 (3)
C4	−0.1442 (2)	0.8837 (2)	1.27638 (10)	0.0531 (3)
C5	0.0143 (2)	0.90272 (19)	1.31801 (10)	0.0540 (3)
C6	0.2068 (2)	0.87655 (18)	1.25750 (10)	0.0503 (3)
C7	0.24799 (18)	0.82807 (16)	1.15335 (9)	0.0403 (3)
C8	0.47691 (17)	0.75240 (16)	0.99773 (9)	0.0412 (3)
C9	0.68526 (19)	0.7217 (2)	0.92895 (11)	0.0546 (3)
H9A	0.7371	0.5987	0.9015	0.082*
H9B	0.7784	0.7393	0.9674	0.082*
H9C	0.6743	0.8075	0.8737	0.082*
C10	0.21267 (19)	0.63937 (19)	0.81444 (9)	0.0465 (3)
H10A	0.1105	0.7551	0.8041	0.056*
H10B	0.1429	0.5643	0.8593	0.056*
C11	0.3226 (2)	0.54186 (19)	0.71328 (10)	0.0523 (3)
H11A	0.4218	0.4258	0.7258	0.063*
H11B	0.2221	0.5146	0.6826	0.063*
C12	0.3726 (3)	0.7066 (2)	0.55269 (11)	0.0625 (4)
C13	0.6852 (3)	0.7454 (3)	0.54185 (14)	0.0820 (5)
H13A	0.6957	0.8634	0.5570	0.098*
H13B	0.8151	0.6739	0.4986	0.098*
C14	0.6363 (3)	0.6450 (3)	0.63974 (11)	0.0682 (4)
H14A	0.7319	0.5209	0.6375	0.082*
H14B	0.6394	0.7098	0.6991	0.082*
N1	0.12438 (14)	0.75658 (13)	1.01023 (7)	0.0406 (2)
N2	0.44386 (15)	0.80020 (15)	1.09343 (8)	0.0462 (3)
N3	0.43028 (18)	0.64507 (16)	0.64066 (8)	0.0534 (3)
O1	0.36793 (12)	0.67107 (12)	0.85906 (6)	0.0460 (2)
O2	0.2172 (2)	0.70974 (18)	0.52691 (9)	0.0879 (4)
O3	0.5186 (2)	0.76983 (16)	0.49204 (8)	0.0829 (4)
H3	−0.220 (2)	0.8300 (19)	1.1449 (11)	0.052 (4)*
H4	−0.280 (2)	0.908 (2)	1.3175 (13)	0.068 (4)*
H5	−0.009 (2)	0.934 (2)	1.3883 (14)	0.064 (4)*
H6	0.322 (3)	0.889 (2)	1.2864 (13)	0.071 (4)*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C1	0.0389 (6)	0.0433 (6)	0.0313 (6)	−0.0140 (5)	−0.0066 (4)	0.0011 (4)
C2	0.0413 (6)	0.0410 (6)	0.0317 (6)	−0.0135 (5)	−0.0066 (4)	0.0011 (4)
C3	0.0439 (7)	0.0559 (7)	0.0406 (7)	−0.0189 (6)	−0.0031 (5)	−0.0016 (5)
C4	0.0526 (7)	0.0592 (8)	0.0396 (7)	−0.0161 (6)	0.0039 (6)	−0.0019 (6)
C5	0.0656 (8)	0.0568 (8)	0.0317 (7)	−0.0106 (6)	−0.0064 (6)	−0.0048 (5)
C6	0.0545 (8)	0.0564 (8)	0.0388 (7)	−0.0113 (6)	−0.0162 (6)	−0.0043 (5)
C7	0.0415 (6)	0.0427 (6)	0.0354 (6)	−0.0106 (5)	−0.0097 (5)	−0.0003 (5)
C8	0.0366 (6)	0.0476 (6)	0.0391 (6)	−0.0127 (5)	−0.0083 (5)	−0.0005 (5)
C9	0.0394 (6)	0.0745 (9)	0.0505 (8)	−0.0210 (6)	−0.0050 (5)	−0.0066 (6)
C10	0.0446 (6)	0.0629 (8)	0.0351 (6)	−0.0211 (6)	−0.0079 (5)	−0.0038 (5)
C11	0.0608 (8)	0.0600 (8)	0.0381 (7)	−0.0217 (6)	−0.0093 (6)	−0.0066 (5)
C12	0.0842 (11)	0.0549 (8)	0.0358 (7)	−0.0028 (8)	−0.0139 (7)	−0.0097 (6)
C13	0.0972 (13)	0.0874 (12)	0.0545 (10)	−0.0363 (10)	0.0076 (9)	0.0021 (8)
C14	0.0723 (10)	0.0929 (11)	0.0440 (8)	−0.0373 (9)	−0.0061 (7)	0.0036 (7)
N1	0.0385 (5)	0.0515 (6)	0.0331 (5)	−0.0169 (4)	−0.0062 (4)	−0.0017 (4)
N2	0.0400 (5)	0.0571 (6)	0.0425 (6)	−0.0140 (5)	−0.0120 (4)	−0.0036 (5)
N3	0.0602 (7)	0.0644 (7)	0.0316 (5)	−0.0157 (5)	−0.0071 (5)	−0.0024 (5)
O1	0.0409 (4)	0.0667 (6)	0.0316 (4)	−0.0203 (4)	−0.0035 (3)	−0.0063 (4)
O2	0.1019 (9)	0.0914 (9)	0.0633 (8)	−0.0034 (7)	−0.0421 (7)	−0.0077 (6)
O3	0.1211 (10)	0.0797 (8)	0.0399 (6)	−0.0288 (7)	−0.0081 (6)	0.0096 (5)

Geometric parameters (Å, º) top

C1—N1	1.2932 (14)	C9—H9C	0.9600
C1—O1	1.3457 (13)	C10—O1	1.4398 (13)
C1—C8	1.4458 (15)	C10—C11	1.5041 (18)
C2—N1	1.3777 (14)	C10—H10A	0.9700
C2—C3	1.4083 (16)	C10—H10B	0.9700
C2—C7	1.4099 (15)	C11—N3	1.4523 (17)
C3—C4	1.3695 (18)	C11—H11A	0.9700
C3—H3	0.966 (14)	C11—H11B	0.9700
C4—C5	1.397 (2)	C12—O2	1.2046 (19)
C4—H4	0.949 (16)	C12—N3	1.3394 (19)
C5—C6	1.3646 (19)	C12—O3	1.357 (2)
C5—H5	0.948 (17)	C13—O3	1.424 (2)
C6—C7	1.4045 (17)	C13—C14	1.510 (2)
C6—H6	0.999 (17)	C13—H13A	0.9700
C7—N2	1.3793 (15)	C13—H13B	0.9700
C8—N2	1.3013 (15)	C14—N3	1.4379 (19)
C8—C9	1.4923 (16)	C14—H14A	0.9700
C9—H9A	0.9600	C14—H14B	0.9700
C9—H9B	0.9600

N1—C1—O1	121.60 (10)	C11—C10—H10A	110.3
N1—C1—C8	124.34 (10)	O1—C10—H10B	110.3
O1—C1—C8	114.06 (9)	C11—C10—H10B	110.3
N1—C2—C3	119.79 (10)	H10A—C10—H10B	108.6
N1—C2—C7	120.95 (10)	N3—C11—C10	114.20 (11)
C3—C2—C7	119.25 (11)	N3—C11—H11A	108.7
C4—C3—C2	119.75 (12)	C10—C11—H11A	108.7
C4—C3—H3	121.5 (9)	N3—C11—H11B	108.7
C2—C3—H3	118.7 (8)	C10—C11—H11B	108.7
C3—C4—C5	121.01 (12)	H11A—C11—H11B	107.6
C3—C4—H4	118.6 (10)	O2—C12—N3	127.96 (16)
C5—C4—H4	120.3 (10)	O2—C12—O3	122.31 (14)
C6—C5—C4	120.14 (12)	N3—C12—O3	109.73 (14)
C6—C5—H5	118.9 (9)	O3—C13—C14	106.05 (14)
C4—C5—H5	120.9 (9)	O3—C13—H13A	110.5
C5—C6—C7	120.42 (12)	C14—C13—H13A	110.5
C5—C6—H6	120.9 (10)	O3—C13—H13B	110.5
C7—C6—H6	118.6 (10)	C14—C13—H13B	110.5
N2—C7—C6	119.74 (10)	H13A—C13—H13B	108.7
N2—C7—C2	120.85 (10)	N3—C14—C13	101.80 (14)
C6—C7—C2	119.41 (11)	N3—C14—H14A	111.4
N2—C8—C1	119.95 (10)	C13—C14—H14A	111.4
N2—C8—C9	120.35 (10)	N3—C14—H14B	111.4
C1—C8—C9	119.70 (11)	C13—C14—H14B	111.4
C8—C9—H9A	109.5	H14A—C14—H14B	109.3
C8—C9—H9B	109.5	C1—N1—C2	115.96 (9)
H9A—C9—H9B	109.5	C8—N2—C7	117.92 (10)
C8—C9—H9C	109.5	C12—N3—C14	112.13 (13)
H9A—C9—H9C	109.5	C12—N3—C11	122.09 (13)
H9B—C9—H9C	109.5	C14—N3—C11	123.42 (12)
O1—C10—C11	106.91 (10)	C1—O1—C10	117.34 (9)
O1—C10—H10A	110.3	C12—O3—C13	109.59 (12)

Experimental details

Crystal data
Chemical formula	C₁₄H₁₅N₃O₃
M_r	273.29
Crystal system, space group	Triclinic, P1
Temperature (K)	296
a, b, c (Å)	6.9936 (3), 7.6916 (3), 13.3709 (6)
α, β, γ (°)	86.649 (2), 77.044 (2), 71.141 (2)
V (Å³)	663.23 (5)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	0.10
Crystal size (mm)	0.41 × 0.33 × 0.20

Data collection
Diffractometer	Bruker X8 APEXII CCD area-detector
Absorption correction	–
No. of measured, independent and observed [I > 2σ(I)] reflections	15358, 3030, 2358
R_int	0.023
(sin θ/λ)_max (Å⁻¹)	0.650

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.040, 0.121, 1.06
No. of reflections	3030
No. of parameters	198
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.21, −0.17

Computer programs: APEX2 (Bruker, 2005), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia,1997) and PLATON (Spek, 2009), WinGX (Farrugia, 1999).

Footnotes

‡Present address: Institute of Nanomaterial and Nanotechnology, Avenue de l'Armée Royale, Rabat, Morocco.

Acknowledgements

The authors thank the Unit of Support for Technical and Scientific Research (UATRS, CNRST) for the X-ray measurements.

References

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