2-(3-Methyl-2-oxo-1,2-di­hydro­quinoxalin-1-yl)acetic acid dihydrate

Missioui, M.; El Fal, M.; Taoufik, J.; Essassi, E.M.; Mague, J.T.; Ramli, Y.

doi:10.1107/S2414314618008829

organic compounds

IUCrDATA

ISSN: 2414-3146

Volume 3| Part 6| June 2018| x180882

https://doi.org/10.1107/S2414314618008829

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2-(3-Methyl-2-oxo-1,2-dihydroquinoxalin-1-yl)acetic acid dihydrate

Mohcine Missioui,^a ^* Mohammed El Fal,^b,^a Jamal Taoufik,^a El Mokhtar Essassi,^b Joel T. Mague ^c and Youssef Ramli ^a

^aLaboratory of Medicinal Chemistry, Faculty of Medicine and Pharmacy, Mohammed V University, Rabat, Morocco, ^bLaboratoire de Chimie Organique Heterocyclique URAC 21, Av. Ibn Battouta, BP, 1014, Faculte des Sciences, Universite Mohammed V, Rabat, Morocco, and ^cDepartment of Chemistry, Tulane University, New Orleans, LA 70118, USA
^*Correspondence e-mail: mohcinemissioui@yahoo.com

Edited by C. Rizzoli, Universita degli Studi di Parma, Italy (Received 8 June 2018; accepted 15 June 2018; online 22 June 2018)

In the title compound, C₁₁H₁₀N₂O₃·2H₂O, the constituent atoms of the dihydroquinoxaline moiety deviate from the mean plane of the unit by +0.0572 (8) to −0.0874 (8) Å while the acetic acid substituent is nearly orthogonal to this plane. The crystal packing consists of corrugated layers constructed by O—H⋯O, O—H⋯N and C—H⋯O hydrogen bonds, which also involve the lattice water molecules. O—H⋯O hydrogen bonds and π–π stacking interactions hold these layers together.

Keywords: crystal structure; dihydroquinoxaline; hydrogen bond; π–π stacking.

CCDC reference: 1849737

Structure description

Quinoxaline derivatives have attracted interest because of their biological and pharmacological activities (Ramli et al., 2014 ; Ramli & Essassi, 2015 ). As a continuation of our work on the synthesis of 3-methylquinoxalin-2-one derivatives in order to evaluate their pharmacological activities (Ramli et al. 2010a ,b , 2011 , 2013 , 2017 , 2018 ; Caleb et al., 2016 ; Missioui et al., 2017 ), the title compound (Fig. 1) was synthesized and its crystal structure is reported here.

Figure 1
The asymmetric unit of the title compound with labelling scheme and 50% probability ellipsoids. The O—H⋯O hydrogen bonds (Table 1

) involving the lattice water molecules are shown as dashed lines.

The dihydroquinoxaline portion of the molecule is not completely planar, as can be seen from the displacements [+0.0572 (8) (N2) to −0.0874 (8) Å (C9)] from the mean plane (r.m.s. deviation = 0.0411 Å) of the bicyclic unit. In addition, a puckering analysis of the heterocyclic ring gave the parameters Q = 0.0893 (11) Å. θ = 72.7 (7)° and φ = 205.6 (8)°. The N2/C10/C11 unit is inclined to the mean plane of the dihydroquinoxaline portion by 82.91 (8)° while the C11/O2/O3 unit is rotated from the N2/C10/C11 unit by 8.4 (2)°.

In the crystal, the main molecule, together with the lattice water molecules, form zigzag chains along the b-axis direction through O3—H3A⋯O4 and O4—H4B⋯N1 hydrogen bonds (Table 1 and Fig. 2). The chains are connected into corrugated layers parallel to the bc plane by O5—H5B⋯O1 hydrogen bonds and the layers are then associated through inversion-related pairs of O5—H5A⋯O2 hydrogen bonds and head-to-tail π–π stacking interactions between inversion-related dihydroquinoxaline moieties [centroid–centroid distance = 3.5295 (7) Å; dihedral angle = 3.33 (5)°; symmetry code 1 − x, 1 − y, 2 − z; Table 1 and Fig. 3].

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O3—H3A⋯O4ⁱ	0.87	1.67	2.5400 (12)	176
C10—H10A⋯O1ⁱⁱ	0.986 (15)	2.334 (15)	3.2524 (14)	154.7 (11)
C10—H10B⋯O4ⁱⁱ	0.989 (15)	2.369 (15)	3.3520 (14)	172.1 (12)
O4—H4A⋯O5	0.87	1.83	2.6966 (11)	171
O4—H4B⋯N1ⁱⁱⁱ	0.87	1.97	2.8344 (13)	171
O5—H5A⋯O2^iv	0.87	1.96	2.8287 (12)	175
O5—H5B⋯O1	0.87	1.96	2.8177 (11)	170
Symmetry codes: (i) $[-x+{\script{1\over 2}}, y-{\script{1\over 2}}, -z+{\script{1\over 2}}]$ ; (ii) -x+1, -y+1, -z+1; (iii) x, y, z-1; (iv) -x, -y+1, -z+1.

Figure 2
Packing diagram of the title compound viewed along the c axis with intermolecular interactions shown as in Fig. 2

Figure 3
Packing diagram of the title compound viewed along the a axis with O—H⋯O, O—H⋯N and C—H⋯O hydrogen bonds (Table 1

) shown, respectively, as red, light-blue and black dashed lines. The π–π stacking interactions are shown as orange dashed lines

Synthesis and crystallization

1 g of ethyl 2- (3-methyl-2-oxoquinoxalin-1(2H)-yl) acetate in 15 ml of a mixture of H₂O/EtOH (50:50 v/v) and 5 ml of 10% NaOH were stirred at room temperature for 1 h. After completion of the reaction (monitored by TLC), the medium was acidified with HCl (3 M). The precipitate obtained was crystallized from ethanol to afford colourless crystals in 55% yield.

Refinement

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

Table 2
Experimental details

Crystal data
Chemical formula	C₁₁H₁₀N₂O₃·2H₂O
M_r	254.24
Crystal system, space group	Monoclinic, P2₁/n
Temperature (K)	150
a, b, c (Å)	7.7306 (5), 16.8048 (11), 9.3113 (6)
β (°)	102.001 (2)
V (Å³)	1183.20 (13)
Z	4
Radiation type	Cu Kα
μ (mm⁻¹)	0.97
Crystal size (mm)	0.21 × 0.15 × 0.08

Data collection
Diffractometer	Bruker D8 VENTURE PHOTON 100 CMOS
Absorption correction	Multi-scan (SADABS; Krause et al., 2015 )
T_min, T_max	0.86, 0.93
No. of measured, independent and observed [I > 2σ(I)] reflections	9051, 2359, 2163
R_int	0.029
(sin θ/λ)_max (Å⁻¹)	0.625

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.031, 0.082, 1.02
No. of reflections	2359
No. of parameters	200
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.22, −0.19
Computer programs: APEX3 and SAINT (Bruker, 2016 ), SHELXT (Sheldrick, 2015a ), SHELXL2018 (Sheldrick, 2015b ), DIAMOND (Brandenburg & Putz, 2012 ) and SHELXTL (Sheldrick, 2008 ).

Structural data

CCDC reference: 1849737

Crystal structure: contains datablocks global, I. DOI: https://doi.org/10.1107/S2414314618008829/rz4025sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2414314618008829/rz4025Isup2.hkl

Supporting information file. DOI: https://doi.org/10.1107/S2414314618008829/rz4025Isup3.cml

checkCIF report

Computing details top

Data collection: APEX3 (Bruker, 2016); cell refinement: SAINT (Bruker, 2016); data reduction: SAINT (Bruker, 2016); program(s) used to solve structure: SHELXT (Sheldrick, 2015a); program(s) used to refine structure: SHELXL2018 (Sheldrick, 2015b); molecular graphics: DIAMOND (Brandenburg & Putz, 2012); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

2-(3-Methyl-2-oxo-1,2-dihydroquinoxalin-1-yl)acetic acid dihydrate top

Crystal data top

C₁₁H₁₀N₂O₃·2H₂O	F(000) = 536
M_r = 254.24	D_x = 1.427 Mg m⁻³
Monoclinic, P2₁/n	Cu Kα radiation, λ = 1.54178 Å
a = 7.7306 (5) Å	Cell parameters from 7699 reflections
b = 16.8048 (11) Å	θ = 5.3–74.5°
c = 9.3113 (6) Å	µ = 0.97 mm⁻¹
β = 102.001 (2)°	T = 150 K
V = 1183.20 (13) Å³	Block, colourless
Z = 4	0.21 × 0.15 × 0.08 mm

Data collection top

Bruker D8 VENTURE PHOTON 100 CMOS diffractometer	2359 independent reflections
Radiation source: INCOATEC IµS micro-focus source	2163 reflections with I > 2σ(I)
Mirror monochromator	R_int = 0.029
Detector resolution: 10.4167 pixels mm^-1	θ_max = 74.5°, θ_min = 5.3°
ω scans	h = −9→9
Absorption correction: multi-scan (SADABS; Krause et al., 2015)	k = −18→21
T_min = 0.86, T_max = 0.93	l = −11→11
9051 measured reflections

Refinement top

Refinement on F²	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: difference Fourier map
R[F² > 2σ(F²)] = 0.031	H atoms treated by a mixture of independent and constrained refinement
wR(F²) = 0.082	w = 1/[σ²(F_o²) + (0.0401P)² + 0.3842P] where P = (F_o² + 2F_c²)/3
S = 1.02	(Δ/σ)_max < 0.001
2359 reflections	Δρ_max = 0.22 e Å⁻³
200 parameters	Δρ_min = −0.19 e Å⁻³
0 restraints	Extinction correction: SHELXL2018 (Sheldrick, 2015b), Fc^*=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.0073 (6)

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. The C-bound H atoms were located in a difference Fourier map and refined freely. As independent refinement of the H atoms attached to oxygen gave unsatisfactory geometries, particularly for H3A, the positions of these atoms were idealized and they were included as riding contributions with U_iso(H) = 1.5 U_eq(O).

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 > 2sigma(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. H-atoms attached to oxygen were placed in locations derived from a difference map, their coordinates were adjusted to give O—H = 0.87 Å and were included as riding contributions.

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

	x	y	z	U_iso*/U_eq
O1	0.29637 (11)	0.52589 (5)	0.56060 (9)	0.0275 (2)
O2	0.23074 (10)	0.31882 (5)	0.56225 (9)	0.0284 (2)
O3	0.49925 (11)	0.28631 (5)	0.52405 (9)	0.0275 (2)
H3A	0.449130	0.245199	0.475735	0.041*
N1	0.20378 (12)	0.53983 (6)	0.91754 (10)	0.0229 (2)
N2	0.37927 (11)	0.44157 (5)	0.75315 (10)	0.0198 (2)
C1	0.35985 (13)	0.41602 (6)	0.89191 (12)	0.0201 (2)
C2	0.42554 (15)	0.34290 (7)	0.95184 (13)	0.0258 (3)
H2	0.487 (2)	0.3067 (10)	0.8985 (18)	0.038 (4)*
C3	0.39994 (17)	0.32121 (8)	1.08882 (14)	0.0308 (3)
H3	0.443 (2)	0.2703 (10)	1.1277 (17)	0.038 (4)*
C4	0.31163 (17)	0.37105 (8)	1.16941 (13)	0.0307 (3)
H4	0.297 (2)	0.3572 (10)	1.2651 (19)	0.040 (4)*
C5	0.24815 (15)	0.44351 (7)	1.11188 (13)	0.0262 (3)
H5	0.188 (2)	0.4802 (9)	1.1667 (16)	0.033 (4)*
C6	0.27024 (14)	0.46666 (6)	0.97219 (12)	0.0209 (2)
C7	0.21326 (15)	0.55956 (7)	0.78503 (12)	0.0227 (2)
C8	0.1406 (2)	0.63718 (8)	0.72178 (14)	0.0340 (3)
H8A	0.226 (2)	0.6636 (11)	0.672 (2)	0.052 (5)*
H8B	0.029 (2)	0.6263 (10)	0.6467 (19)	0.044 (4)*
H8C	0.109 (3)	0.6704 (12)	0.798 (2)	0.058 (5)*
C9	0.29624 (14)	0.50840 (6)	0.68914 (12)	0.0209 (2)
C10	0.48739 (14)	0.39698 (7)	0.67001 (12)	0.0217 (2)
H10A	0.5238 (19)	0.4329 (9)	0.5980 (16)	0.028 (3)*
H10B	0.592 (2)	0.3753 (9)	0.7384 (16)	0.031 (4)*
C11	0.38939 (14)	0.32998 (7)	0.58021 (11)	0.0214 (2)
O4	0.13522 (11)	0.66176 (5)	0.10852 (9)	0.0262 (2)
H4A	0.091253	0.642524	0.180009	0.039*
H4B	0.144293	0.623447	0.047672	0.039*
O5	0.03254 (10)	0.59251 (5)	0.33839 (8)	0.0271 (2)
H5A	−0.048291	0.617676	0.373004	0.041*
H5B	0.113130	0.576940	0.412786	0.041*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O1	0.0292 (4)	0.0330 (5)	0.0219 (4)	0.0051 (3)	0.0089 (3)	0.0055 (3)
O2	0.0208 (4)	0.0309 (4)	0.0330 (4)	−0.0003 (3)	0.0045 (3)	−0.0072 (4)
O3	0.0254 (4)	0.0258 (4)	0.0329 (5)	0.0021 (3)	0.0099 (3)	−0.0062 (3)
N1	0.0235 (5)	0.0236 (5)	0.0208 (4)	0.0005 (4)	0.0027 (4)	−0.0018 (4)
N2	0.0186 (4)	0.0208 (4)	0.0203 (4)	−0.0003 (3)	0.0043 (3)	−0.0004 (4)
C1	0.0169 (5)	0.0222 (5)	0.0204 (5)	−0.0037 (4)	0.0015 (4)	−0.0003 (4)
C2	0.0245 (5)	0.0238 (6)	0.0282 (6)	0.0003 (4)	0.0036 (4)	0.0014 (5)
C3	0.0311 (6)	0.0279 (6)	0.0314 (6)	0.0007 (5)	0.0024 (5)	0.0082 (5)
C4	0.0323 (6)	0.0362 (7)	0.0231 (6)	−0.0028 (5)	0.0045 (5)	0.0085 (5)
C5	0.0253 (6)	0.0310 (6)	0.0219 (5)	−0.0022 (5)	0.0040 (4)	−0.0008 (5)
C6	0.0188 (5)	0.0219 (5)	0.0208 (5)	−0.0022 (4)	0.0012 (4)	−0.0009 (4)
C7	0.0235 (5)	0.0230 (5)	0.0209 (5)	0.0002 (4)	0.0028 (4)	−0.0013 (4)
C8	0.0493 (8)	0.0278 (6)	0.0250 (6)	0.0129 (6)	0.0079 (6)	0.0016 (5)
C9	0.0191 (5)	0.0221 (5)	0.0211 (5)	−0.0016 (4)	0.0036 (4)	0.0010 (4)
C10	0.0187 (5)	0.0239 (5)	0.0231 (5)	0.0015 (4)	0.0060 (4)	0.0004 (4)
C11	0.0217 (5)	0.0230 (5)	0.0196 (5)	0.0028 (4)	0.0049 (4)	0.0031 (4)
O4	0.0319 (4)	0.0259 (4)	0.0219 (4)	0.0014 (3)	0.0080 (3)	0.0012 (3)
O5	0.0235 (4)	0.0364 (5)	0.0216 (4)	0.0037 (3)	0.0051 (3)	0.0016 (3)

Geometric parameters (Å, º) top

O1—C9	1.2326 (14)	C4—H4	0.950 (17)
O2—C11	1.2173 (14)	C5—C6	1.4017 (16)
O3—C11	1.3107 (13)	C5—H5	0.978 (16)
O3—H3A	0.8703	C7—C9	1.4785 (15)
N1—C7	1.2944 (15)	C7—C8	1.4919 (16)
N1—C6	1.3878 (15)	C8—H8A	0.989 (19)
N2—C9	1.3673 (14)	C8—H8B	1.011 (18)
N2—C1	1.3989 (14)	C8—H8C	0.98 (2)
N2—C10	1.4589 (14)	C10—C11	1.5092 (15)
C1—C2	1.4005 (16)	C10—H10A	0.986 (15)
C1—C6	1.4064 (16)	C10—H10B	0.989 (15)
C2—C3	1.3797 (18)	O4—H4A	0.8702
C2—H2	0.972 (16)	O4—H4B	0.8701
C3—C4	1.3941 (19)	O5—H5A	0.8700
C3—H3	0.961 (17)	O5—H5B	0.8700
C4—C5	1.3788 (18)

C11—O3—H3A	113.3	N1—C7—C9	122.98 (10)
C7—N1—C6	119.11 (10)	N1—C7—C8	120.60 (10)
C9—N2—C1	121.59 (9)	C9—C7—C8	116.42 (10)
C9—N2—C10	117.35 (9)	C7—C8—H8A	110.1 (11)
C1—N2—C10	121.05 (9)	C7—C8—H8B	108.2 (10)
N2—C1—C2	122.52 (10)	H8A—C8—H8B	108.6 (14)
N2—C1—C6	117.68 (10)	C7—C8—H8C	110.1 (12)
C2—C1—C6	119.80 (10)	H8A—C8—H8C	112.3 (15)
C3—C2—C1	119.36 (11)	H8B—C8—H8C	107.4 (15)
C3—C2—H2	119.2 (10)	O1—C9—N2	121.60 (10)
C1—C2—H2	121.4 (10)	O1—C9—C7	122.39 (10)
C2—C3—C4	121.28 (11)	N2—C9—C7	115.96 (9)
C2—C3—H3	118.5 (9)	N2—C10—C11	113.59 (9)
C4—C3—H3	120.2 (9)	N2—C10—H10A	108.8 (8)
C5—C4—C3	119.73 (11)	C11—C10—H10A	105.1 (8)
C5—C4—H4	118.5 (10)	N2—C10—H10B	109.2 (8)
C3—C4—H4	121.7 (10)	C11—C10—H10B	109.4 (9)
C4—C5—C6	120.23 (11)	H10A—C10—H10B	110.6 (12)
C4—C5—H5	121.6 (9)	O2—C11—O3	125.23 (10)
C6—C5—H5	118.2 (9)	O2—C11—C10	124.50 (10)
N1—C6—C5	118.61 (10)	O3—C11—C10	110.27 (9)
N1—C6—C1	121.80 (10)	H4A—O4—H4B	108.7
C5—C6—C1	119.59 (10)	H5A—O5—H5B	107.6

C9—N2—C1—C2	171.99 (10)	C2—C1—C6—C5	0.25 (15)
C10—N2—C1—C2	−7.10 (15)	C6—N1—C7—C9	−1.59 (16)
C9—N2—C1—C6	−7.91 (14)	C6—N1—C7—C8	179.03 (11)
C10—N2—C1—C6	172.99 (9)	C1—N2—C9—O1	−171.44 (10)
N2—C1—C2—C3	−179.34 (10)	C10—N2—C9—O1	7.68 (15)
C6—C1—C2—C3	0.55 (16)	C1—N2—C9—C7	10.93 (14)
C1—C2—C3—C4	−0.71 (18)	C10—N2—C9—C7	−169.95 (9)
C2—C3—C4—C5	0.03 (19)	N1—C7—C9—O1	176.13 (11)
C3—C4—C5—C6	0.79 (18)	C8—C7—C9—O1	−4.46 (16)
C7—N1—C6—C5	−175.57 (10)	N1—C7—C9—N2	−6.26 (16)
C7—N1—C6—C1	5.03 (16)	C8—C7—C9—N2	173.15 (10)
C4—C5—C6—N1	179.66 (10)	C9—N2—C10—C11	−93.62 (11)
C4—C5—C6—C1	−0.93 (17)	C1—N2—C10—C11	85.51 (12)
N2—C1—C6—N1	−0.45 (15)	N2—C10—C11—O2	8.67 (16)
C2—C1—C6—N1	179.64 (10)	N2—C10—C11—O3	−171.79 (9)
N2—C1—C6—C5	−179.85 (9)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O3—H3A···O4ⁱ	0.87	1.67	2.5400 (12)	176
C10—H10A···O1ⁱⁱ	0.986 (15)	2.334 (15)	3.2524 (14)	154.7 (11)
C10—H10B···O4ⁱⁱ	0.989 (15)	2.369 (15)	3.3520 (14)	172.1 (12)
O4—H4A···O5	0.87	1.83	2.6966 (11)	171
O4—H4B···N1ⁱⁱⁱ	0.87	1.97	2.8344 (13)	171
O5—H5A···O2^iv	0.87	1.96	2.8287 (12)	175
O5—H5B···O1	0.87	1.96	2.8177 (11)	170

Symmetry codes: (i) −x+1/2, y−1/2, −z+1/2; (ii) −x+1, −y+1, −z+1; (iii) x, y, z−1; (iv) −x, −y+1, −z+1.

Funding information

The support of NSF–MRI grant No. 1228232 for the purchase of the diffractometer and Tulane University for support of the Tulane Crystallography Laboratory are gratefully acknowledged.

References

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