2-Oxo-2H-chromen-7-yl 4-ethyl­benzoate

Goulizan-Bi, S.D.; Bazié, H.; N'Gouan, A.J.; Djandé, A.; Kakou-Yao, R.; Lecomte, C.

doi:10.1107/S2414314625010302

organic compounds

IUCrDATA

ISSN: 2414-3146

Volume 10| Part 11| November 2025| x251030

https://doi.org/10.1107/S2414314625010302

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2-Oxo-2H-chromen-7-yl 4-ethylbenzoate

Séverin Dri Goulizan-Bi,^a ^* Hypolite Bazié,^b Aka Joseph N'Gouan,^a Abdoulaye Djandé,^b Rita Kakou-Yao ^a and Claude Lecomte ^c

^aLaboratory of Material Sciences, Environnement and Solar Energy, Research Team: Crystallography and Molecular Physics, University Félix Houphouët-Boigny, 22 BP 582 Abidjan 22, Côte d'Ivoire, ^bLaboratory of Molecular Chemistry and Materials, Research Team: Organic Chemistry and Phytochemistry, University Joseph KI-ZERBO, 03 BP 7021, Ouagadougou 03, Burkina Faso, and ^cCRM2, CNRS-Université de Lorraine, Vandoeuvre-lès-Nancy CEDEX BP 70239, France
^*Correspondence e-mail: [email protected]

Edited by W. T. A. Harrison, University of Aberdeen, United Kingdom (Received 10 November 2025; accepted 17 November 2025; online 21 November 2025)

In the title compound, C₁₈H₁₄O₄, the benzoate ring is oriented at a dihedral angle of 39.78 (5)° with respect to the coumarin ring system. In the crystal, the molecules are linked by C—H⋯O hydrogen bonds to generate infinite (101) layers.

Keywords: crystal structure; Hirshfeld surface analysis; coumarin.

CCDC reference: 2503393

Structure description

The title compound, C₁₈H₁₄O₄ (I), crystallizes in the monoclinic space group P2₁/c with one molecule in the asymmetric unit (Fig. 1). The side chain is titled with respect to the chromen-2-one ring system with torsion angles C18—C10—O2—C9 = −51.22 (16)° and C11—C10—O2—C9 = 133.18 (11)°. The C10–C18/O3 coumarin ring system is almost planar (r.m.s deviation = 0.012 Å) and makes a dihedral angle with the pendant benzoate ring system of 39.78 (5)°. The C14—C15 [1.342 (2) Å] and C15—C16 [1.447 (2) Å] bond lengths are consistent with the double and single bonds in the Lewis structure of (I) and with those in similar coumarin derivatives (Gomes et al., 2016 ; Ouédraogo et al., 2018 ).

Figure 1
The molecular structure of (I) with displacement ellipsoids drawn at the 50% probability level.

In the extended structure of (I), the molecules are connected by C—H⋯O hydrogen bonds (Table 1): the C11—H11⋯O1 and C12—H12⋯O3 bonds lead to [010] chains, which are cross-linked by the C15—H15⋯O4 bonds to generate (101) layers incorporating R₂²(11) and R₃³(13) loops (Fig. 2). The intermolecular interactions in (I) were further quantified by Hirshfeld surface (Fig. 3) analysis using CrystalExplorer (Spackman et al., 2021 ): the two-dimensional fingerprint plots for (I) (Fig. 4) show that the greatest contributions are from H⋯H (40.5%), H⋯O/O⋯H (26.1%) C⋯H/H⋯C (18.4%) and C⋯C (9.0%) contacts.

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C11—H11⋯O1ⁱ	0.943 (17)	2.527 (18)	3.4535 (16)	167.8 (14)
C12—H12⋯O3ⁱ	0.972 (18)	2.597 (18)	3.3166 (15)	131.0 (13)
C15—H15⋯O4ⁱⁱ	0.97 (2)	2.38 (2)	3.2871 (16)	155.1 (15)
Symmetry codes: (i) ; (ii) $[-x+1, y+{\script{1\over 2}}, -z+{\script{3\over 2}}]$ .

Figure 2
A view of the crystal packing of (I) showing C–H⋯O hydrogen bonds to form R₂²(11) and R₃³(13) loops extending parallel to the ac plane. H atoms not involved in the hydrogen bonds omitted.

Figure 3
The Hirshfeld surface of (I) mapped over d_norm. Dotted lines represent hydrogen bonds

Figure 4
Fingerprint plots for (I) showing (a) H⋯H, (b) O⋯H, (c) C⋯H, (d) C⋯C, (e) C⋯O, (f) O⋯O interactions. The outline of the full fingerprint is shown in grey: d_i is the closest internal distance from a given point on the Hirshfeld surface and d_e is the closest external contact.

Synthesis and crystallization

In a 100 ml round-bottom flask equipped with a condenser, 4-ethylbenzoyl chloride (0.95 ml, 6.2 mmol, ∼1 equiv.) was dissolved in 30 ml of tetrahydrofuran and then were added dried triethylamine (2.6 ml, 3 equiv.) and 7-hydroxycoumarin (1 g, 6.17 mmol, 1 equiv.) in small portions over 30 min. While stirring, the mixture was refluxed for 4 h and poured into 40 ml of chloroform. The solution was acidified with dilute hydrochloric acid until its discoloration was complete. The organic phase was extracted, concentrated in a vacuum until a slight cloudiness was obtained and cooled in an ice bath. The resulting precipitate was filtered off with suction, washed with petroleum ether and recrystallized from a chloroform/n-hexane (1:3) solvent mixture resulting in a white powder of the title compound (1.15 g, 70% yield, m.p. = 407–409 K). Colorless crystals of (I) suitable for single-crystal X-ray diffraction analysis were then obtained by slow evaporation of an acetone solution.

Refinement

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

Table 2
Experimental details

Crystal data
Chemical formula	C₁₈H₁₄O₄
M_r	294.29
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	293
a, b, c (Å)	11.4837 (5), 6.1481 (3), 19.9255 (9)
β (°)	97.386 (2)
V (Å³)	1395.13 (11)
Z	4
Radiation type	Mo Kα
μ (mm⁻¹)	0.10
Crystal size (mm)	0.24 × 0.06 × 0.06

Data collection
Diffractometer	Bruker D8 Venture
Absorption correction	Multi-scan (SADABS; Krause et al., 2015 )
T_min, T_max	0.712, 0.746
No. of measured, independent and observed [I > 2σ(I)] reflections	70676, 4305, 3095
R_int	0.058
(sin θ/λ)_max (Å⁻¹)	0.717

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.050, 0.156, 1.06
No. of reflections	4305
No. of parameters	255
H-atom treatment	All H-atom parameters refined
Δρ_max, Δρ_min (e Å⁻³)	0.22, −0.31
Computer programs: CrysAlis PRO (Rigaku OD, 2022 ), SHELXT2018/2 (Sheldrick, 2015a ), SHELXL2018/3 (Sheldrick, 2015b ), PLATON (Spek,2020 ) and WinGX (Farrugia, 2012 ) and publCIF (Westrip, 2010 ).

Structural data

CCDC reference: 2503393

Crystal structure: contains datablock I. DOI: https://doi.org/10.1107/S2414314625010302/hb4544sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2414314625010302/hb4544Isup2.hkl

Supporting information file. DOI: https://doi.org/10.1107/S2414314625010302/hb4544Isup3.cml

checkCIF report

Computing details top

2-Oxo-2H-chromen-7-yl 4-ethylbenzoate top

Crystal data top

C₁₈H₁₄O₄	D_x = 1.401 Mg m⁻³
M_r = 294.29	Melting point = 407–409 K
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
a = 11.4837 (5) Å	Cell parameters from 4940 reflections
b = 6.1481 (3) Å	θ = 5.1–61.3°
c = 19.9255 (9) Å	µ = 0.10 mm⁻¹
β = 97.386 (2)°	T = 293 K
V = 1395.13 (11) Å³	Prism, colourless
Z = 4	0.24 × 0.06 × 0.06 mm
F(000) = 616

Data collection top

Bruker D8 Venture diffractometer	3095 reflections with I > 2σ(I)
Radiation source: micro-focus sealed X-ray tube	R_int = 0.058
ω scans	θ_max = 30.7°, θ_min = 2.6°
Absorption correction: multi-scan (SADABS; Krause et al., 2015)	h = −16→16
T_min = 0.712, T_max = 0.746	k = −8→8
70676 measured reflections	l = −28→28
4305 independent reflections

Refinement top

Refinement on F²	0 restraints
Least-squares matrix: full	Hydrogen site location: difference Fourier map
R[F² > 2σ(F²)] = 0.050	All H-atom parameters refined
wR(F²) = 0.156	w = 1/[σ²(F_o²) + (0.0889P)² + 0.2456P] where P = (F_o² + 2F_c²)/3
S = 1.06	(Δ/σ)_max = 0.001
4305 reflections	Δρ_max = 0.22 e Å⁻³
255 parameters	Δρ_min = −0.31 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.

Refinement. The H atoms were located in difference maps and their positions and U_iso values were freely refined.

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

	x	y	z	U_iso*/U_eq
O2	0.71504 (8)	0.42159 (14)	0.38731 (4)	0.0248 (2)
O3	0.55289 (8)	0.14242 (14)	0.57921 (4)	0.0252 (2)
O1	0.80649 (9)	0.09594 (16)	0.40536 (5)	0.0323 (2)
O4	0.46888 (9)	0.00631 (16)	0.66357 (5)	0.0344 (2)
C17	0.60586 (10)	0.31085 (19)	0.54905 (6)	0.0219 (2)
C10	0.68769 (10)	0.4389 (2)	0.45336 (6)	0.0231 (2)
C9	0.77633 (10)	0.2465 (2)	0.36850 (6)	0.0244 (2)
C6	0.80475 (10)	0.2753 (2)	0.29849 (6)	0.0235 (2)
C18	0.63433 (11)	0.2719 (2)	0.48430 (6)	0.0235 (2)
C5	0.78305 (11)	0.4703 (2)	0.26297 (6)	0.0258 (2)
C13	0.62824 (10)	0.50917 (19)	0.58229 (6)	0.0234 (2)
C3	0.87510 (11)	0.3251 (2)	0.16904 (6)	0.0262 (3)
C11	0.71028 (11)	0.6413 (2)	0.48389 (6)	0.0256 (2)
C8	0.89493 (11)	0.1307 (2)	0.20483 (7)	0.0275 (3)
C7	0.86050 (11)	0.1057 (2)	0.26900 (6)	0.0263 (2)
C16	0.51819 (11)	0.1624 (2)	0.64297 (6)	0.0259 (3)
C4	0.81888 (11)	0.4938 (2)	0.19946 (6)	0.0273 (3)
C14	0.59507 (11)	0.5311 (2)	0.64935 (6)	0.0266 (3)
C15	0.54372 (11)	0.3659 (2)	0.67835 (6)	0.0267 (3)
C12	0.68011 (11)	0.6754 (2)	0.54797 (7)	0.0269 (3)
C2	0.91348 (12)	0.3636 (2)	0.10002 (6)	0.0302 (3)
C1	0.98427 (15)	0.1831 (3)	0.07278 (8)	0.0391 (3)
H2A	0.9611 (14)	0.505 (3)	0.1025 (8)	0.034 (4)*
H7	0.8742 (14)	−0.032 (3)	0.2945 (8)	0.035 (4)*
H8	0.9368 (15)	0.002 (3)	0.1848 (8)	0.038 (4)*
H4	0.8076 (14)	0.636 (3)	0.1754 (8)	0.035 (4)*
H2B	0.8427 (15)	0.393 (3)	0.0674 (8)	0.036 (4)*
H5	0.7432 (15)	0.596 (3)	0.2835 (8)	0.036 (4)*
H1B	1.0623 (18)	0.151 (3)	0.1047 (10)	0.052 (5)*
H11	0.7455 (14)	0.751 (3)	0.4603 (8)	0.033 (4)*
H1C	0.9376 (17)	0.043 (3)	0.0665 (11)	0.059 (6)*
H18	0.6161 (15)	0.136 (3)	0.4624 (8)	0.034 (4)*
H1A	1.0048 (16)	0.222 (3)	0.0264 (9)	0.044 (5)*
H12	0.6935 (15)	0.816 (3)	0.5699 (9)	0.043 (5)*
H15	0.5194 (16)	0.377 (3)	0.7232 (10)	0.045 (5)*
H14	0.6115 (15)	0.671 (3)	0.6738 (8)	0.037 (4)*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O2	0.0296 (4)	0.0253 (4)	0.0205 (4)	0.0027 (3)	0.0076 (3)	0.0016 (3)
O3	0.0322 (5)	0.0251 (4)	0.0193 (4)	−0.0033 (3)	0.0070 (3)	−0.0004 (3)
O1	0.0364 (5)	0.0323 (5)	0.0300 (5)	0.0082 (4)	0.0115 (4)	0.0091 (4)
O4	0.0460 (6)	0.0333 (5)	0.0259 (4)	−0.0070 (4)	0.0115 (4)	0.0030 (4)
C17	0.0226 (5)	0.0231 (5)	0.0201 (5)	−0.0005 (4)	0.0033 (4)	0.0018 (4)
C10	0.0230 (5)	0.0280 (6)	0.0187 (5)	0.0018 (4)	0.0041 (4)	0.0009 (4)
C9	0.0233 (5)	0.0255 (6)	0.0252 (5)	0.0004 (4)	0.0055 (4)	0.0008 (4)
C6	0.0231 (5)	0.0272 (6)	0.0206 (5)	−0.0016 (4)	0.0042 (4)	0.0000 (4)
C18	0.0262 (6)	0.0247 (5)	0.0197 (5)	−0.0006 (4)	0.0035 (4)	−0.0013 (4)
C5	0.0279 (6)	0.0273 (6)	0.0226 (5)	0.0013 (5)	0.0051 (4)	0.0006 (4)
C13	0.0225 (5)	0.0256 (5)	0.0220 (5)	0.0017 (4)	0.0031 (4)	−0.0021 (4)
C3	0.0233 (5)	0.0335 (6)	0.0217 (5)	−0.0021 (5)	0.0031 (4)	−0.0019 (5)
C11	0.0263 (6)	0.0245 (5)	0.0270 (6)	−0.0005 (4)	0.0069 (5)	0.0017 (4)
C8	0.0258 (6)	0.0303 (6)	0.0272 (6)	0.0011 (5)	0.0061 (5)	−0.0039 (5)
C7	0.0260 (6)	0.0272 (6)	0.0260 (6)	0.0008 (5)	0.0049 (5)	0.0005 (5)
C16	0.0287 (6)	0.0310 (6)	0.0187 (5)	0.0011 (5)	0.0057 (4)	0.0018 (4)
C4	0.0296 (6)	0.0300 (6)	0.0226 (5)	0.0002 (5)	0.0044 (5)	0.0017 (5)
C14	0.0277 (6)	0.0279 (6)	0.0244 (5)	0.0010 (5)	0.0043 (4)	−0.0044 (4)
C15	0.0290 (6)	0.0311 (6)	0.0207 (5)	0.0021 (5)	0.0052 (4)	−0.0016 (4)
C12	0.0285 (6)	0.0240 (6)	0.0290 (6)	−0.0002 (4)	0.0070 (5)	−0.0027 (4)
C2	0.0282 (6)	0.0411 (7)	0.0218 (6)	−0.0004 (5)	0.0056 (5)	−0.0016 (5)
C1	0.0434 (8)	0.0451 (8)	0.0315 (7)	0.0000 (7)	0.0157 (6)	−0.0066 (6)

Geometric parameters (Å, º) top

O2—C9	1.3644 (14)	C3—C4	1.4003 (18)
O2—C10	1.3958 (13)	C3—C2	1.5157 (17)
O3—C17	1.3774 (14)	C11—C12	1.3813 (17)
O3—C16	1.3850 (14)	C11—H11	0.941 (17)
O1—C9	1.2048 (15)	C8—C7	1.3946 (17)
O4—C16	1.2126 (15)	C8—H8	1.035 (17)
C17—C18	1.3918 (15)	C7—H7	0.990 (17)
C17—C13	1.3956 (16)	C16—C15	1.4474 (18)
C10—C18	1.3807 (16)	C4—H4	0.995 (17)
C10—C11	1.3948 (17)	C14—C15	1.3417 (18)
C9—C6	1.4836 (16)	C14—H14	0.994 (17)
C6—C7	1.3925 (17)	C15—H15	0.973 (18)
C6—C5	1.3980 (17)	C12—H12	0.972 (18)
C18—H18	0.952 (17)	C2—C1	1.517 (2)
C5—C4	1.3876 (16)	C2—H2A	1.022 (17)
C5—H5	1.009 (17)	C2—H2B	0.990 (17)
C13—C12	1.4040 (17)	C1—H1B	1.05 (2)
C13—C14	1.4421 (16)	C1—H1C	1.01 (2)
C3—C8	1.3956 (18)	C1—H1A	1.011 (18)

C9—O2—C10	120.37 (9)	C3—C8—H8	120.9 (9)
C17—O3—C16	121.92 (9)	C6—C7—C8	120.29 (12)
O3—C17—C18	116.40 (10)	C6—C7—H7	118.4 (9)
O3—C17—C13	120.96 (10)	C8—C7—H7	121.4 (9)
C18—C17—C13	122.63 (11)	O4—C16—O3	116.24 (11)
C18—C10—C11	122.47 (11)	O4—C16—C15	126.41 (11)
C18—C10—O2	122.07 (10)	O3—C16—C15	117.35 (10)
C11—C10—O2	115.30 (10)	C5—C4—C3	121.65 (12)
O1—C9—O2	123.83 (11)	C5—C4—H4	119.7 (9)
O1—C9—C6	125.74 (11)	C3—C4—H4	118.6 (9)
O2—C9—C6	110.36 (10)	C15—C14—C13	120.76 (11)
C7—C6—C5	119.36 (11)	C15—C14—H14	120.6 (10)
C7—C6—C9	118.44 (11)	C13—C14—H14	118.6 (10)
C5—C6—C9	122.12 (11)	C14—C15—C16	121.14 (11)
C10—C18—C17	117.17 (11)	C14—C15—H15	122.6 (11)
C10—C18—H18	122.0 (10)	C16—C15—H15	116.2 (11)
C17—C18—H18	120.8 (10)	C11—C12—C13	120.82 (11)
C4—C5—C6	119.78 (11)	C11—C12—H12	120.4 (11)
C4—C5—H5	119.5 (9)	C13—C12—H12	118.8 (10)
C6—C5—H5	120.7 (9)	C3—C2—C1	116.26 (12)
C17—C13—C12	117.94 (11)	C3—C2—H2A	107.8 (9)
C17—C13—C14	117.83 (11)	C1—C2—H2A	109.2 (9)
C12—C13—C14	124.23 (11)	C3—C2—H2B	108.3 (9)
C8—C3—C4	117.86 (11)	C1—C2—H2B	109.3 (10)
C8—C3—C2	123.35 (11)	H2A—C2—H2B	105.4 (13)
C4—C3—C2	118.77 (11)	C2—C1—H1B	112.1 (10)
C12—C11—C10	118.94 (11)	C2—C1—H1C	111.5 (11)
C12—C11—H11	121.9 (10)	H1B—C1—H1C	108.3 (16)
C10—C11—H11	119.2 (10)	C2—C1—H1A	110.5 (11)
C7—C8—C3	121.06 (11)	H1B—C1—H1A	108.5 (14)
C7—C8—H8	118.1 (9)	H1C—C1—H1A	105.7 (15)

C16—O3—C17—C18	−178.68 (10)	O2—C10—C11—C12	176.73 (11)
C16—O3—C17—C13	0.87 (17)	C4—C3—C8—C7	−0.39 (19)
C9—O2—C10—C18	−51.22 (17)	C2—C3—C8—C7	178.31 (12)
C9—O2—C10—C11	133.19 (11)	C5—C6—C7—C8	0.37 (19)
C10—O2—C9—O1	2.72 (18)	C9—C6—C7—C8	−176.26 (11)
C10—O2—C9—C6	−174.39 (10)	C3—C8—C7—C6	0.4 (2)
O1—C9—C6—C7	7.17 (19)	C17—O3—C16—O4	177.58 (11)
O2—C9—C6—C7	−175.79 (10)	C17—O3—C16—C15	−2.29 (16)
O1—C9—C6—C5	−169.36 (13)	C6—C5—C4—C3	1.05 (19)
O2—C9—C6—C5	7.68 (16)	C8—C3—C4—C5	−0.32 (19)
C11—C10—C18—C17	−1.63 (18)	C2—C3—C4—C5	−179.08 (11)
O2—C10—C18—C17	−176.91 (10)	C17—C13—C14—C15	−0.42 (18)
O3—C17—C18—C10	−179.88 (10)	C12—C13—C14—C15	178.69 (12)
C13—C17—C18—C10	0.58 (18)	C13—C14—C15—C16	−1.07 (19)
C7—C6—C5—C4	−1.06 (19)	O4—C16—C15—C14	−177.46 (13)
C9—C6—C5—C4	175.44 (11)	O3—C16—C15—C14	2.40 (18)
O3—C17—C13—C12	−178.62 (10)	C10—C11—C12—C13	0.43 (19)
C18—C17—C13—C12	0.90 (18)	C17—C13—C12—C11	−1.41 (18)
O3—C17—C13—C14	0.54 (17)	C14—C13—C12—C11	179.49 (12)
C18—C17—C13—C14	−179.94 (11)	C8—C3—C2—C1	−4.46 (19)
C18—C10—C11—C12	1.16 (19)	C4—C3—C2—C1	174.23 (12)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C11—H11···O1ⁱ	0.943 (17)	2.527 (18)	3.4535 (16)	167.8 (14)
C12—H12···O3ⁱ	0.972 (18)	2.597 (18)	3.3166 (15)	131.0 (13)
C15—H15···O4ⁱⁱ	0.97 (2)	2.38 (2)	3.2871 (16)	155.1 (15)

Symmetry codes: (i) x, y+1, z; (ii) −x+1, y+1/2, −z+3/2.

Acknowledgements

The authors thank the AFRAMED project, and the Institute Jean Barriol (Université de Lorraine, France) for X-ray diffraction measurements.

References

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