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Journal logoIUCrDATA
ISSN: 2414-3146

Ethyl 2-{[2-(2-eth­­oxy-2-oxoeth­­oxy)quinolin-4-yl]carbon­yl­oxy}acetate

CROSSMARK_Color_square_no_text.svg

aLaboratoire de Chimie Organique Hétérocyclique, Centre de Recherche Des Sciences des Médicaments, Pôle de Compétence Pharmacochimie, Av Ibn Battouta, BP 1014, Faculté des Sciences, Université Mohammed V, Rabat, Morocco, and bDepartment of Chemistry, Tulane University, New Orleans, LA 70118, USA
*Correspondence e-mail: Bouzianyounes@gmail.com

Edited by W. T. A. Harrison, University of Aberdeen, Scotland (Received 9 October 2018; accepted 11 October 2018; online 16 October 2018)

The conformation of the 2-eth­oxy-2-oxoeth­oxy side chain, including a gauche Ce—O—C—C3 [72.46 (16)°] (e = eth­oxy) unit, in the title compound, C18H19NO7, is partly determined by an intra­molecular C—H⋯O hydrogen bond. In the crystal, C—H⋯O hydrogen bonds and C—H⋯π inter­actions arising from the same methyl­ene group form chains extending along the a-axis direction.

3D view (loading...)
[Scheme 3D1]
Chemical scheme
[Scheme 1]

Structure description

Quinoline derivatives have various biological properties including anti­bacterial (Kidwai et al., 2000[Kidwai, M., Bhushan, K., Sapra, P., Saxena, R. & Gupta, R. (2000). Bioorg. Med. Chem. 8, 69-72.]) anti­viral (Wathen et al., 2002[Wathen, M. W. (2002). Rev. Med. Virol. 12, 167-178.]), anti­cancer (Chen et al., 2013[Chen, H., Yang, Z., Ding, C., Chu, L., Zhang, Y., Terry, K., Liu, H., Shen, Q. & Zhou, J. (2013). Eur. J. Med. Chem. 62, 498-507.]) and anti­malarial (Kunin & Ellise, 2000[Kunin, C. M. & Ellis, W. Y. (2000). Antimicrob. Agents Chemother. 44, 848-852.]) activity. As part of our studies in this area, we now describe the synthesis and structure of the title compound.

As expected, the quinoline core of the mol­ecule is almost planar (r.m.s. deviation = 0.0149) with N1 deviating by the largest amount [0.0272 (9) Å]. The orientation of the inner portion of the side chain emanating from C7 is partially determined by an intra­molecular C5—H5⋯O5 hydrogen bond (Fig. 1[link] and Table 1[link]). In the crystal, the mol­ecules form chains extending along the a-axis direction through a combination of C10—H10A⋯O2 hydrogen bonds and C10—H10BCg2 inter­actions (Table 1[link] and Fig. 2[link]). The chains pack with inter­calation of the shorter side chains on one side and the longer ones on the other and with the quinoline moieties alternately up and down from one chain to the next (Fig. 3[link]).

Table 1
Hydrogen-bond geometry (Å, °)

Cg2 is the centroid of the C1–C6 ring.

D—H⋯A D—H H⋯A DA D—H⋯A
C5—H5⋯O5 0.977 (19) 2.244 (17) 2.8681 (17) 120.7 (14)
C10—H10A⋯O2i 0.954 (19) 2.435 (19) 3.3079 (16) 152.1 (15)
C10—H10BCg2i 0.983 (17) 3.249 (16) 4.0173 (14) 136.3 (15)
Symmetry code: (i) x+1, y, z.
[Figure 1]
Figure 1
The title mol­ecule showing 50% probability ellipsoids. The intra­molecular hydrogen bond is shown by a dashed line.
[Figure 2]
Figure 2
A portion of the hydrogen-bonded chain viewed along the b-axis direction. C—H⋯O hydrogen bonds and C—H⋯π(ring) inter­actions are shown, respectively, by black and green dashed lines.
[Figure 3]
Figure 3
Packing viewed along the b-axis direction with inter­molecular inter­actions depicted as in Fig. 2[link].

Synthesis and crystallization

A solution of 0.8 g (4.23 mmol) of 2-oxo-1,2-di­hydro­quin­oline-4-carb­oxy­lic acid in 25 ml of DMF was mixed with 0.94 ml (8.46 mmol) ethyl bromo­acetate, 1.17 g (8.46 mmol) K2CO3 and 0.13 g (0.423 mmol) tetra-n-butylammonium bromide (TBAB). The reaction mixture was stirred at room temperature in DMF for 24 h. After removal of salts by filtration, the DMF was evaporated under reduced pressure and the residue obtained was dissolved in di­chloro­methane. The organic phase was dried over Na2SO4 then concentrated in vacuo. The resulting mixture was chromatographed on a silica gel column [eluent: ethyl acetate/hexane (1/9)]. Colourless blocks were obtained when the solvent was allowed to evaporate (yield: 20%).

Refinement

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

Table 2
Experimental details

Crystal data
Chemical formula C18H19NO7
Mr 361.34
Crystal system, space group Triclinic, P[\overline{1}]
Temperature (K) 150
a, b, c (Å) 4.9417 (2), 7.6157 (3), 23.4472 (9)
α, β, γ (°) 94.490 (2), 92.997 (2), 98.136 (2)
V3) 869.06 (6)
Z 2
Radiation type Cu Kα
μ (mm−1) 0.91
Crystal size (mm) 0.19 × 0.14 × 0.08
 
Data collection
Diffractometer Bruker D8 VENTURE PHOTON 100 CMOS
Absorption correction Multi-scan (SADABS; Krause et al., 2015[Krause, L., Herbst-Irmer, R., Sheldrick, G. M. & Stalke, D. (2015). J. Appl. Cryst. 48, 3-10.])
Tmin, Tmax 0.85, 0.93
No. of measured, independent and observed [I > 2σ(I)] reflections 6827, 3301, 2894
Rint 0.023
(sin θ/λ)max−1) 0.625
 
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.037, 0.099, 1.03
No. of reflections 3301
No. of parameters 312
H-atom treatment All H-atom parameters refined
Δρmax, Δρmin (e Å−3) 0.29, −0.20
Computer programs: APEX3 and SAINT (Bruker, 2016[Bruker (2016). APEX3, SAINT and SADABS. Bruker AXS, Inc., Madison, Wisconsin, USA.]), SHELXT (Sheldrick, 2015a[Sheldrick, G. M. (2015a). Acta Cryst. A71, 3-8.]), SHELXL2018/1 (Sheldrick, 2015b[Sheldrick, G. M. (2015b). Acta Cryst. C71, 3-8.]), DIAMOND (Brandenburg & Putz, 2012[Brandenburg, K. & Putz, H. (2012). DIAMOND, Crystal Impact GbR, Bonn, Germany.]) and SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]).

Structural data


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: SHELXL2018/1 (Sheldrick, 2015b); molecular graphics: DIAMOND (Brandenburg & Putz, 2012); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Ethyl 2-{[2-(2-ethoxy-2-oxoethoxy)quinolin-4-yl]carbonyloxy}acetate top
Crystal data top
C18H19NO7Z = 2
Mr = 361.34F(000) = 380
Triclinic, P1Dx = 1.381 Mg m3
a = 4.9417 (2) ÅCu Kα radiation, λ = 1.54178 Å
b = 7.6157 (3) ÅCell parameters from 5397 reflections
c = 23.4472 (9) Åθ = 3.8–74.5°
α = 94.490 (2)°µ = 0.91 mm1
β = 92.997 (2)°T = 150 K
γ = 98.136 (2)°Block, colourless
V = 869.06 (6) Å30.19 × 0.14 × 0.08 mm
Data collection top
Bruker D8 VENTURE PHOTON 100 CMOS
diffractometer
3301 independent reflections
Radiation source: INCOATEC IµS micro–focus source2894 reflections with I > 2σ(I)
Mirror monochromatorRint = 0.023
Detector resolution: 10.4167 pixels mm-1θmax = 74.5°, θmin = 3.8°
ω scansh = 56
Absorption correction: multi-scan
(SADABS; Krause et al., 2015)
k = 99
Tmin = 0.85, Tmax = 0.93l = 2729
6827 measured reflections
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.037All H-atom parameters refined
wR(F2) = 0.099 w = 1/[σ2(Fo2) + (0.0479P)2 + 0.2771P]
where P = (Fo2 + 2Fc2)/3
S = 1.03(Δ/σ)max < 0.001
3301 reflectionsΔρmax = 0.29 e Å3
312 parametersΔρmin = 0.19 e Å3
0 restraintsExtinction correction: SHELXL-2018/1 (Sheldrick, 2015b), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.0144 (10)
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 > 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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
O10.9795 (2)0.19616 (13)0.19654 (4)0.0298 (2)
O20.6525 (2)0.10059 (14)0.09687 (4)0.0347 (3)
O30.9762 (2)0.24142 (13)0.04573 (4)0.0314 (2)
O40.3329 (3)0.15037 (15)0.35154 (5)0.0549 (4)
O50.3071 (2)0.43440 (13)0.37905 (4)0.0317 (2)
O60.5808 (2)0.31430 (16)0.46977 (5)0.0409 (3)
O70.1851 (2)0.22790 (15)0.50923 (4)0.0370 (3)
N10.7797 (2)0.45027 (15)0.19139 (5)0.0264 (3)
C10.6133 (3)0.56258 (17)0.21529 (5)0.0253 (3)
C20.5848 (3)0.71671 (19)0.18733 (6)0.0322 (3)
H20.691 (4)0.735 (2)0.1526 (8)0.041 (5)*
C30.4194 (3)0.83331 (19)0.20776 (6)0.0348 (3)
H30.403 (4)0.937 (3)0.1890 (8)0.043 (5)*
C40.2734 (3)0.80006 (19)0.25639 (6)0.0341 (3)
H40.157 (4)0.883 (3)0.2708 (8)0.046 (5)*
C50.2999 (3)0.65216 (19)0.28472 (6)0.0304 (3)
H50.198 (4)0.632 (2)0.3188 (8)0.042 (5)*
C60.4736 (3)0.53005 (17)0.26569 (5)0.0250 (3)
C70.5175 (3)0.37093 (17)0.29200 (5)0.0258 (3)
C80.6876 (3)0.26321 (18)0.26838 (6)0.0266 (3)
H80.720 (3)0.155 (2)0.2853 (7)0.035 (4)*
C90.8144 (3)0.31020 (17)0.21775 (5)0.0246 (3)
C101.0894 (3)0.2362 (2)0.14312 (6)0.0291 (3)
H10A1.229 (4)0.163 (2)0.1374 (7)0.040 (5)*
H10B1.164 (3)0.363 (2)0.1426 (7)0.032 (4)*
C110.8761 (3)0.18459 (17)0.09398 (6)0.0257 (3)
C120.7954 (3)0.1969 (2)0.00618 (6)0.0393 (4)
H12A0.743 (4)0.062 (3)0.0114 (8)0.052 (5)*
H12B0.632 (4)0.253 (3)0.0010 (8)0.052 (5)*
C130.9522 (4)0.2659 (3)0.05472 (7)0.0476 (4)
H13A1.130 (5)0.207 (3)0.0576 (10)0.072 (7)*
H13B0.832 (5)0.235 (3)0.0907 (10)0.070 (7)*
H13C1.009 (5)0.394 (3)0.0492 (10)0.066 (6)*
C140.3772 (3)0.30534 (19)0.34306 (6)0.0309 (3)
C150.1559 (3)0.3732 (2)0.42636 (6)0.0339 (3)
H15A0.005 (4)0.282 (3)0.4126 (8)0.042 (5)*
H15B0.094 (4)0.479 (3)0.4439 (8)0.043 (5)*
C160.3364 (3)0.30131 (18)0.46988 (6)0.0273 (3)
C170.3261 (3)0.1532 (2)0.55576 (7)0.0376 (4)
H17A0.341 (4)0.031 (3)0.5435 (8)0.052 (5)*
H17B0.506 (4)0.219 (3)0.5618 (8)0.047 (5)*
C180.1607 (4)0.1651 (2)0.60672 (7)0.0403 (4)
H18A0.249 (4)0.113 (3)0.6388 (9)0.058 (6)*
H18B0.019 (4)0.104 (3)0.5980 (8)0.050 (5)*
H18C0.158 (5)0.296 (3)0.6203 (10)0.069 (7)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0316 (5)0.0373 (5)0.0231 (5)0.0121 (4)0.0057 (4)0.0030 (4)
O20.0276 (5)0.0424 (6)0.0325 (5)0.0004 (4)0.0062 (4)0.0021 (4)
O30.0311 (5)0.0395 (5)0.0225 (5)0.0015 (4)0.0016 (4)0.0026 (4)
O40.0931 (10)0.0301 (6)0.0388 (6)0.0094 (6)0.0309 (6)0.0011 (5)
O50.0359 (5)0.0364 (5)0.0256 (5)0.0087 (4)0.0141 (4)0.0053 (4)
O60.0265 (5)0.0575 (7)0.0419 (6)0.0097 (5)0.0125 (4)0.0108 (5)
O70.0269 (5)0.0550 (7)0.0322 (5)0.0067 (4)0.0076 (4)0.0185 (5)
N10.0264 (5)0.0309 (6)0.0215 (5)0.0026 (4)0.0019 (4)0.0021 (4)
C10.0249 (6)0.0277 (6)0.0218 (6)0.0015 (5)0.0017 (5)0.0010 (5)
C20.0378 (8)0.0332 (7)0.0250 (7)0.0013 (6)0.0016 (6)0.0061 (5)
C30.0440 (8)0.0274 (7)0.0322 (7)0.0055 (6)0.0067 (6)0.0039 (6)
C40.0369 (8)0.0305 (7)0.0339 (8)0.0089 (6)0.0044 (6)0.0055 (6)
C50.0320 (7)0.0331 (7)0.0251 (7)0.0032 (6)0.0034 (6)0.0029 (5)
C60.0250 (6)0.0261 (6)0.0217 (6)0.0002 (5)0.0021 (5)0.0012 (5)
C70.0268 (6)0.0278 (6)0.0208 (6)0.0018 (5)0.0019 (5)0.0007 (5)
C80.0310 (7)0.0269 (6)0.0213 (6)0.0029 (5)0.0011 (5)0.0018 (5)
C90.0240 (6)0.0292 (6)0.0199 (6)0.0033 (5)0.0001 (5)0.0004 (5)
C100.0245 (6)0.0410 (8)0.0230 (7)0.0074 (6)0.0057 (5)0.0016 (5)
C110.0250 (6)0.0275 (6)0.0257 (7)0.0079 (5)0.0057 (5)0.0006 (5)
C120.0373 (8)0.0537 (10)0.0257 (7)0.0070 (7)0.0040 (6)0.0009 (6)
C130.0662 (12)0.0509 (10)0.0253 (8)0.0065 (9)0.0009 (8)0.0049 (7)
C140.0345 (7)0.0309 (7)0.0253 (7)0.0017 (6)0.0064 (6)0.0013 (5)
C150.0299 (7)0.0479 (9)0.0264 (7)0.0073 (6)0.0128 (6)0.0094 (6)
C160.0268 (7)0.0290 (6)0.0267 (7)0.0046 (5)0.0094 (5)0.0001 (5)
C170.0367 (8)0.0459 (9)0.0349 (8)0.0153 (7)0.0064 (6)0.0138 (7)
C180.0368 (8)0.0522 (10)0.0323 (8)0.0047 (7)0.0024 (7)0.0097 (7)
Geometric parameters (Å, º) top
O1—C91.3577 (15)C6—C71.4401 (19)
O1—C101.4285 (16)C7—C81.3633 (19)
O2—C111.2036 (17)C7—C141.4988 (19)
O3—C111.3367 (16)C8—C91.4180 (18)
O3—C121.4598 (17)C8—H80.972 (18)
O4—C141.2035 (19)C10—C111.5092 (19)
O5—C141.3399 (17)C10—H10A0.954 (19)
O5—C151.4405 (16)C10—H10B0.983 (17)
O6—C161.1978 (17)C12—C131.498 (2)
O7—C161.3259 (17)C12—H12A1.02 (2)
O7—C171.4593 (18)C12—H12B0.97 (2)
N1—C91.3012 (17)C13—H13A1.05 (2)
N1—C11.3762 (17)C13—H13B1.00 (2)
C1—C21.4090 (19)C13—H13C0.97 (2)
C1—C61.4201 (19)C15—C161.506 (2)
C2—C31.366 (2)C15—H15A0.96 (2)
C2—H21.001 (18)C15—H15B0.97 (2)
C3—C41.402 (2)C17—C181.486 (2)
C3—H30.943 (19)C17—H17A0.97 (2)
C4—C51.370 (2)C17—H17B0.95 (2)
C4—H40.966 (19)C18—H18A0.99 (2)
C5—C61.4152 (19)C18—H18B0.95 (2)
C5—H50.978 (19)C18—H18C1.03 (3)
C9—O1—C10115.23 (10)O2—C11—C10125.79 (12)
C11—O3—C12116.03 (11)O3—C11—C10109.56 (11)
C14—O5—C15115.02 (11)O3—C12—C13106.86 (13)
C16—O7—C17117.59 (11)O3—C12—H12A108.1 (11)
C9—N1—C1117.42 (11)C13—C12—H12A111.8 (11)
N1—C1—C2116.81 (12)O3—C12—H12B108.2 (12)
N1—C1—C6123.38 (12)C13—C12—H12B112.1 (12)
C2—C1—C6119.81 (12)H12A—C12—H12B109.6 (16)
C3—C2—C1120.40 (13)C12—C13—H13A109.5 (13)
C3—C2—H2123.1 (10)C12—C13—H13B108.0 (13)
C1—C2—H2116.5 (10)H13A—C13—H13B110.2 (18)
C2—C3—C4120.43 (13)C12—C13—H13C112.1 (13)
C2—C3—H3119.8 (11)H13A—C13—H13C107.2 (19)
C4—C3—H3119.7 (11)H13B—C13—H13C109.8 (19)
C5—C4—C3120.31 (13)O4—C14—O5122.56 (13)
C5—C4—H4119.4 (11)O4—C14—C7123.18 (13)
C3—C4—H4120.3 (11)O5—C14—C7114.25 (12)
C4—C5—C6121.04 (13)O5—C15—C16111.47 (11)
C4—C5—H5118.9 (11)O5—C15—H15A110.1 (11)
C6—C5—H5120.0 (11)C16—C15—H15A109.7 (11)
C5—C6—C1117.97 (12)O5—C15—H15B104.6 (11)
C5—C6—C7125.85 (12)C16—C15—H15B108.7 (11)
C1—C6—C7116.16 (12)H15A—C15—H15B112.2 (15)
C8—C7—C6119.62 (12)O6—C16—O7125.43 (13)
C8—C7—C14115.35 (12)O6—C16—C15124.80 (13)
C6—C7—C14124.95 (12)O7—C16—C15109.73 (11)
C7—C8—C9118.76 (12)O7—C17—C18107.62 (12)
C7—C8—H8121.0 (10)O7—C17—H17A108.0 (12)
C9—C8—H8120.2 (10)C18—C17—H17A111.4 (12)
N1—C9—O1119.94 (11)O7—C17—H17B107.5 (12)
N1—C9—C8124.63 (12)C18—C17—H17B113.4 (12)
O1—C9—C8115.43 (11)H17A—C17—H17B108.7 (16)
O1—C10—C11111.20 (11)C17—C18—H18A109.5 (12)
O1—C10—H10A106.4 (11)C17—C18—H18B110.4 (12)
C11—C10—H10A107.0 (11)H18A—C18—H18B109.9 (17)
O1—C10—H10B112.6 (9)C17—C18—H18C109.8 (13)
C11—C10—H10B109.0 (10)H18A—C18—H18C106.2 (18)
H10A—C10—H10B110.5 (15)H18B—C18—H18C111.0 (17)
O2—C11—O3124.61 (12)
C9—N1—C1—C2177.99 (12)C10—O1—C9—C8175.21 (11)
C9—N1—C1—C61.91 (18)C7—C8—C9—N10.3 (2)
N1—C1—C2—C3178.82 (13)C7—C8—C9—O1179.63 (11)
C6—C1—C2—C31.3 (2)C9—O1—C10—C1176.01 (14)
C1—C2—C3—C40.8 (2)C12—O3—C11—O20.38 (19)
C2—C3—C4—C51.5 (2)C12—O3—C11—C10178.34 (12)
C3—C4—C5—C60.1 (2)O1—C10—C11—O28.81 (19)
C4—C5—C6—C11.89 (19)O1—C10—C11—O3173.25 (10)
C4—C5—C6—C7179.92 (12)C11—O3—C12—C13177.61 (13)
N1—C1—C6—C5177.54 (12)C15—O5—C14—O44.6 (2)
C2—C1—C6—C52.56 (18)C15—O5—C14—C7176.06 (11)
N1—C1—C6—C70.83 (18)C8—C7—C14—O425.5 (2)
C2—C1—C6—C7179.08 (12)C6—C7—C14—O4151.15 (16)
C5—C6—C7—C8178.79 (12)C8—C7—C14—O5153.84 (12)
C1—C6—C7—C80.57 (18)C6—C7—C14—O529.51 (19)
C5—C6—C7—C142.3 (2)C14—O5—C15—C1672.46 (16)
C1—C6—C7—C14175.94 (12)C17—O7—C16—O61.3 (2)
C6—C7—C8—C90.84 (19)C17—O7—C16—C15178.99 (13)
C14—C7—C8—C9175.99 (11)O5—C15—C16—O69.4 (2)
C1—N1—C9—O1179.05 (11)O5—C15—C16—O7172.89 (12)
C1—N1—C9—C81.65 (19)C16—O7—C17—C18151.56 (14)
C10—O1—C9—N14.16 (17)
Hydrogen-bond geometry (Å, º) top
Cg2 is the centroid of the C1–C6 ring.
D—H···AD—HH···AD···AD—H···A
C5—H5···O50.977 (19)2.244 (17)2.8681 (17)120.7 (14)
C10—H10A···O2i0.954 (19)2.435 (19)3.3079 (16)152.1 (15)
C10—H10B···Cg2i0.983 (17)3.249 (16)4.0173 (14)136.3 (15)
Symmetry code: (i) x+1, y, z.
 

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.

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