2-Oxochromen-4-yl 4-(dimethyl­amino)­benzoate

Abou, A.; Djandé, A.; Sessouma, B.; Saba, A.; Kakou-Yao, R.

doi:10.1107/S1600536811030844

organic compounds

CRYSTALLOGRAPHIC
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ISSN: 2056-9890

Volume 67| Part 9| September 2011| Pages o2269-o2270

doi:10.1107/S1600536811030844

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2-Oxochromen-4-yl 4-(dimethylamino)benzoate

Akoun Abou,^a ^* Abdoulaye Djandé,^b Bintou Sessouma,^b Adama Saba ^b and Rita Kakou-Yao ^a

^aLaboratoire de Cristallographie et Physique Moléculaire, UFR SSMT, Université de Cocody 22 BP 582 Abidjan 22, Côte d'Ivoire, and ^bLaboratoire de Chimie Bio-organique et Phytochimie, Université de Ouagadougou 03 BP 7021 Ouagadougou 03, Burkina Faso
^*Correspondence e-mail: abou_akoun@yahoo.fr

(Received 18 July 2011; accepted 1 August 2011; online 6 August 2011)

In the title molecule, C₁₈H₁₅NO₄, the benzoate ring is oriented at a dihedral angle of 43.43 (6)° with respect to the planar [maximum deviation = 0.038 (2) Å] chromene ring. The crystal structure features R₂²(12) centrosymetric dimers formed via C—H⋯O interactions and these dimeric aggregates are connected by C—H⋯π interactions.

Related literature

For the biological activity of coumarin derivatives, see: Ukhov et al. (2001 ); Abd Elhafez et al. (2003 ); Basanagouda et al. (2009 ); Liu et al. (2008 ); Trapkov et al. (1996 ); Vukovic et al. (2010 ); Emmanuel-Giota et al. (2001 ); Hamdi & Dixneuf (2007 ); Wang et al. (2001 ); Marchenko et al. (2006 ). For hydrogen-bond graph-set motifs, see: Bernstein et al. (1995 ).

Experimental

Crystal data

C₁₈H₁₅NO₄
M_r = 309.32
Triclinic, $[P \overline 1]$
a = 7.4939 (2) Å
b = 10.2361 (3) Å
c = 10.6620 (3) Å
α = 92.307 (3)°
β = 103.935 (1)°
γ = 109.852 (2)°
V = 739.92 (4) Å³
Z = 2
Mo Kα radiation
μ = 0.10 mm⁻¹
T = 298 K
0.50 × 0.40 × 0.30 mm

Data collection

Nonius KappaCCD diffractometer
8424 measured reflections
3590 independent reflections
2897 reflections with I > 2σ(I)
R_int = 0.024

Refinement

R[F² > 2σ(F²)] = 0.048
wR(F²) = 0.120
S = 0.98
3585 reflections
208 parameters
H-atom parameters constrained
Δρ_max = 0.23 e Å⁻³
Δρ_min = −0.20 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

Cg3 is the centroid of the C15–C18/C22/C23 ring.

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C9—H91⋯O8ⁱ	0.96	2.49	3.449 (2)	171
C7—H71⋯Cg3ⁱⁱ	0.95	2.84	3.429 (2)	121
C20—H202⋯Cg3ⁱⁱⁱ	0.99	2.91	3.777 (2)	146
Symmetry codes: (i) -x, -y, -z-1; (ii) -x, -y+1, -z; (iii) -x+1, -y+1, -z+1.

Data collection: COLLECT (Nonius, 2001 ); cell refinement: DENZO/SCALEPACK (Otwinowski & Minor, 1997 ); data reduction: DENZO/SCALEPACK; program(s) used to solve structure: SIR92 (Altomare et al., 1994 ); program(s) used to refine structure: CRYSTALS (Betteridge et al., 2003 ); molecular graphics: PLATON (Spek, 2009 ); software used to prepare material for publication: CRYSTALS.

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536811030844/tk2767sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536811030844/tk2767Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536811030844/tk2767Isup3.cml

checkCIF report

Comment top

Coumarin constitutes one of the major classes of naturally occurring compounds, and interest in its chemistry continues unabated because of its usefulness as biologically active agents. It also represents the core structure of several molecules of pharmaceutical importance. Coumarin and its derivatives have been reported to serve as anti-bacterial (Ukhov et al., 2001; Abd Elhafez et al., 2003; Basanagouda et al., 2009; Liu et al., 2008), anti-oxidant (Trapkov et al., 1996; Vukovic et al., 2010), anti-inflammatory (Emmanuel-Giota et al., 2001; Hamdi & Dixneuf, 2007), anti-coagulant (Hamdi et al., 2007) and anti-tumour (Wang et al., 2001; Marchenko et al., 2006) agents. Therefore, the synthesis of new coumarin derivatives is of considerable interest. In order to study the influence of new substituents on the activity of the coumarin derivative, the title compound, (I), has been synthesized and in this paper, we present its molecular structure, Fig. 1.

In (I), the planar chromene ring system resulting from the two coupled rings (benzene and 3,6-dihydro-2H-pyran) is oriented with respect to the benzoate-benzene ring at a dihedral angle of 43.43 (6)°. Atoms O14, N19, C13 and C21 are 0.046 (1), 0.052 (1), 0.079 (2) and 0.077 (3) Å out of the plane of the benzoate-benzene ring, respectively, so, they are coplanar with this ring.

In the crystal structure, intermolecular C—H···O interactions (Table 1) link the molecules into centrosymmetric dimers through R₂²(12) ring motifs (Bernstein et al., 1995) (Fig. 2). Two weak C—H···π interactions formed between the H71 and H202 atoms and the centroid Cg3 of the benzoate-benzene ring (Table 1 and Fig. 3) further stabilize the structure.

Related literature top

For the biological activity of coumarin derivatives, see: Ukhov et al. (2001); Abd Elhafez et al. (2003); Basanagouda et al. (2009); Liu et al. (2008); Trapkov et al. (1996); Vukovic et al. (2010); Emmanuel-Giota et al. (2001); Hamdi & Dixneuf (2007); Wang et al. (2001); Marchenko et al. (2006). For hydrogen-bond graph-set motifs, see: Bernstein et al. (1995).

Experimental top

To a solution of 4.10^-2 mole of paradimethylamino benzoyl chloride in 150 ml of dried tetrahydrofuran, was added 0.12 mole of dried triethylamine and 4.10^-2 mole of 4-hydroxycoumarin by small portions over 30 min. The mixture was then refluxed for 3 h and poured in 300 ml of chloroform or dichloromethane. The solution was acidified with dilute hydrochloric acid until the pH was 2 or 3. The organic layer was extracted, washed with water, dried over MgSO₄ and the solvent removed. The crude product was recrystallized in chloroform. Colourless crystals of the title compound are obtained in a good yield: 82.6%; M.pt. 445 K.

Computing details top

Data collection: COLLECT (Nonius, 2001); cell refinement: DENZO/SCALEPACK (Otwinowski & Minor, 1997); data reduction: DENZO/SCALEPACK (Otwinowski & Minor, 1997); program(s) used to solve structure: SIR92 (Altomare et al., 1994); program(s) used to refine structure: CRYSTALS (Betteridge et al., 2003); molecular graphics: PLATON (Spek, 2009); software used to prepare material for publication: CRYSTALS (Betteridge et al., 2003).

Figures top

	Fig. 1. The molecular structure of (I) showing the atomic labeling scheme, with displacement ellipsoids drawn at the 50% probability level. H atoms are shown as spheres of arbitrary radius.
	Fig. 2. Crystal packing, viewed in projection down the b axis, showing parallel centrosymmetric dimers. Dashed lines indicate hydrogen bonds. H atoms not involved in hydrogen bonds have been omitted for clarity.
	Fig. 3. Crystal packing, showing C—H···π stacking interactions. The green dots are centroids of rings. H atoms not involved in C—H···π interactions have been omitted for clarity.

2-Oxochromen-4-yl 4-(dimethylamino)benzoate top

Crystal data top

C₁₈H₁₅NO₄	Z = 2
M_r = 309.32	F(000) = 324
Triclinic, P1	D_x = 1.388 Mg m⁻³
Hall symbol: -P 1	Melting point: 445 K
a = 7.4939 (2) Å	Mo Kα radiation, λ = 0.71073 Å
b = 10.2361 (3) Å	Cell parameters from 8424 reflections
c = 10.6620 (3) Å	θ = 2.0–28.7°
α = 92.307 (3)°	µ = 0.10 mm⁻¹
β = 103.935 (1)°	T = 298 K
γ = 109.852 (2)°	Parallelepiped, colourless
V = 739.92 (4) Å³	0.50 × 0.40 × 0.30 mm

Data collection top

Nonius KappaCCD diffractometer	2897 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	R_int = 0.024
Graphite monochromator	θ_max = 28.7°, θ_min = 2.0°
ϕ and ω scans	h = −9→9
8424 measured reflections	k = −13→13
3590 independent reflections	l = −14→14

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)] = 0.048	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.120	H-atom parameters constrained
S = 0.98	Method = Modified Sheldrick w = 1/[σ²(F²) + (0.05P)² + 0.22P], where P = [max(F_o²,0) + 2F_c²]/3
3585 reflections	(Δ/σ)_max = 0.00023
208 parameters	Δρ_max = 0.23 e Å⁻³
0 restraints	Δρ_min = −0.20 e Å⁻³
60 constraints

Crystal data top

C₁₈H₁₅NO₄	γ = 109.852 (2)°
M_r = 309.32	V = 739.92 (4) Å³
Triclinic, P1	Z = 2
a = 7.4939 (2) Å	Mo Kα radiation
b = 10.2361 (3) Å	µ = 0.10 mm⁻¹
c = 10.6620 (3) Å	T = 298 K
α = 92.307 (3)°	0.50 × 0.40 × 0.30 mm
β = 103.935 (1)°

Data collection top

Nonius KappaCCD diffractometer	2897 reflections with I > 2σ(I)
8424 measured reflections	R_int = 0.024
3590 independent reflections

Refinement top

R[F² > 2σ(F²)] = 0.048	0 restraints
wR(F²) = 0.120	H-atom parameters constrained
S = 0.98	Δρ_max = 0.23 e Å⁻³
3585 reflections	Δρ_min = −0.20 e Å⁻³
208 parameters

Special details top

Refinement. The 5 reflections 1 0 0; 0 1 0; -1 0 1; 0 0 1; -1 1 1 have been measured with too low intensities. It might be caused by some systematical error, probably by shielding by a beam stop of these diffractions. They were not used in the refinement.

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

	x	y	z	U_iso*/U_eq
O1	0.16941 (15)	0.34698 (9)	−0.00111 (8)	0.0462
C2	0.13553 (19)	0.27238 (13)	−0.11979 (11)	0.0385
C3	0.16678 (17)	0.14123 (12)	−0.10953 (12)	0.0363
C4	0.12326 (18)	0.05485 (13)	−0.22545 (12)	0.0396
O5	0.05704 (15)	0.09384 (10)	−0.34457 (9)	0.0493
C6	0.0349 (2)	0.22168 (15)	−0.35487 (13)	0.0480
C7	0.0715 (2)	0.31027 (14)	−0.23575 (13)	0.0453
O8	−0.0149 (2)	0.24941 (13)	−0.46358 (10)	0.0703
C9	0.1466 (2)	−0.07411 (14)	−0.22593 (15)	0.0499
C10	0.2154 (2)	−0.11591 (15)	−0.10867 (16)	0.0531
C11	0.2611 (2)	−0.03116 (15)	0.00810 (15)	0.0504
C12	0.2373 (2)	0.09635 (14)	0.00783 (13)	0.0436
C13	0.26101 (19)	0.49181 (13)	0.02252 (12)	0.0394
O14	0.31022 (19)	0.56038 (11)	−0.06000 (10)	0.0605
C15	0.29273 (18)	0.54219 (12)	0.15893 (11)	0.0361
C16	0.40333 (19)	0.68335 (13)	0.20353 (12)	0.0399
C17	0.4486 (2)	0.73643 (14)	0.33261 (13)	0.0438
C18	0.38190 (19)	0.64988 (14)	0.42412 (12)	0.0399
N19	0.42952 (19)	0.70056 (13)	0.55279 (11)	0.0513
C20	0.3356 (3)	0.61733 (19)	0.64173 (14)	0.0591
C21	0.5486 (4)	0.8446 (2)	0.59983 (17)	0.0903
C22	0.2647 (2)	0.50796 (14)	0.37750 (12)	0.0422
C23	0.22417 (19)	0.45612 (13)	0.24879 (12)	0.0402
H71	0.0500	0.3963	−0.2441	0.0557*
H91	0.1132	−0.1320	−0.3079	0.0600*
H101	0.2329	−0.2053	−0.1062	0.0641*
H111	0.3097	−0.0605	0.0902	0.0601*
H121	0.2673	0.1552	0.0875	0.0528*
H161	0.4492	0.7442	0.1416	0.0485*
H171	0.5265	0.8322	0.3594	0.0528*
H201	0.3856	0.6702	0.7280	0.0885*
H203	0.1930	0.5921	0.6121	0.0885*
H202	0.3622	0.5286	0.6450	0.0885*
H211	0.5837	0.8563	0.6932	0.1350*
H213	0.4752	0.9046	0.5672	0.1350*
H212	0.6655	0.8711	0.5708	0.1350*
H221	0.2121	0.4466	0.4367	0.0519*
H231	0.1484	0.3589	0.2193	0.0481*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O1	0.0692 (6)	0.0362 (5)	0.0336 (4)	0.0168 (4)	0.0184 (4)	0.0015 (4)
C2	0.0442 (7)	0.0376 (6)	0.0332 (6)	0.0136 (5)	0.0122 (5)	0.0005 (5)
C3	0.0355 (6)	0.0348 (6)	0.0363 (6)	0.0096 (5)	0.0109 (5)	0.0019 (5)
C4	0.0397 (6)	0.0371 (6)	0.0375 (6)	0.0095 (5)	0.0095 (5)	0.0001 (5)
O5	0.0631 (6)	0.0452 (5)	0.0345 (5)	0.0183 (5)	0.0072 (4)	−0.0028 (4)
C6	0.0555 (8)	0.0498 (8)	0.0358 (6)	0.0196 (6)	0.0069 (6)	0.0016 (6)
C7	0.0571 (8)	0.0444 (7)	0.0378 (6)	0.0241 (6)	0.0105 (6)	0.0042 (5)
O8	0.1030 (10)	0.0720 (8)	0.0340 (5)	0.0396 (7)	0.0038 (5)	0.0047 (5)
C9	0.0537 (8)	0.0389 (7)	0.0534 (8)	0.0137 (6)	0.0140 (6)	−0.0039 (6)
C10	0.0543 (8)	0.0396 (7)	0.0668 (9)	0.0197 (6)	0.0150 (7)	0.0058 (6)
C11	0.0500 (8)	0.0478 (8)	0.0534 (8)	0.0194 (6)	0.0104 (6)	0.0122 (6)
C12	0.0467 (7)	0.0439 (7)	0.0382 (6)	0.0149 (6)	0.0099 (5)	0.0052 (5)
C13	0.0487 (7)	0.0361 (6)	0.0357 (6)	0.0171 (5)	0.0133 (5)	0.0045 (5)
O14	0.0936 (8)	0.0462 (6)	0.0392 (5)	0.0159 (5)	0.0266 (5)	0.0087 (4)
C15	0.0419 (6)	0.0361 (6)	0.0331 (6)	0.0161 (5)	0.0124 (5)	0.0044 (5)
C16	0.0461 (7)	0.0368 (6)	0.0379 (6)	0.0129 (5)	0.0159 (5)	0.0076 (5)
C17	0.0477 (7)	0.0367 (6)	0.0415 (7)	0.0090 (5)	0.0120 (5)	0.0012 (5)
C18	0.0423 (7)	0.0456 (7)	0.0324 (6)	0.0185 (5)	0.0077 (5)	0.0033 (5)
N19	0.0632 (8)	0.0545 (7)	0.0319 (5)	0.0193 (6)	0.0086 (5)	0.0011 (5)
C20	0.0716 (10)	0.0777 (11)	0.0347 (7)	0.0325 (9)	0.0179 (7)	0.0104 (7)
C21	0.1312 (19)	0.0643 (11)	0.0409 (9)	0.0037 (11)	0.0096 (10)	−0.0089 (8)
C22	0.0506 (7)	0.0418 (7)	0.0366 (6)	0.0160 (6)	0.0163 (5)	0.0102 (5)
C23	0.0474 (7)	0.0344 (6)	0.0385 (6)	0.0128 (5)	0.0139 (5)	0.0048 (5)

Geometric parameters (Å, º) top

O1—C2	1.3728 (14)	C13—C15	1.4586 (16)
O1—C13	1.3885 (15)	C15—C16	1.3937 (17)
C2—C3	1.4430 (17)	C15—C23	1.3985 (17)
C2—C7	1.3373 (18)	C16—C17	1.3762 (17)
C3—C4	1.3920 (16)	C16—H161	0.969
C3—C12	1.3958 (17)	C17—C18	1.4110 (18)
C4—O5	1.3749 (15)	C17—H171	0.944
C4—C9	1.3892 (18)	C18—N19	1.3637 (16)
O5—C6	1.3794 (17)	C18—C22	1.4121 (18)
C6—C7	1.4425 (18)	N19—C20	1.4490 (19)
C6—O8	1.2056 (16)	N19—C21	1.433 (2)
C7—H71	0.952	C20—H201	0.967
C9—C10	1.376 (2)	C20—H203	0.976
C9—H91	0.965	C20—H202	0.994
C10—C11	1.388 (2)	C21—H211	0.958
C10—H101	0.967	C21—H213	0.977
C11—C12	1.3764 (19)	C21—H212	0.956
C11—H111	0.965	C22—C23	1.3742 (17)
C12—H121	0.954	C22—H221	0.965
C13—O14	1.1970 (15)	C23—H231	0.958

C2—O1—C13	122.05 (10)	C13—C15—C23	123.81 (11)
O1—C2—C3	113.36 (10)	C16—C15—C23	117.98 (11)
O1—C2—C7	125.23 (12)	C15—C16—C17	121.34 (11)
C3—C2—C7	121.35 (11)	C15—C16—H161	118.6
C2—C3—C4	117.02 (11)	C17—C16—H161	120.1
C2—C3—C12	124.46 (11)	C16—C17—C18	120.99 (12)
C4—C3—C12	118.52 (12)	C16—C17—H171	118.8
C3—C4—O5	121.54 (11)	C18—C17—H171	120.2
C3—C4—C9	121.44 (12)	C17—C18—N19	121.52 (12)
O5—C4—C9	117.02 (11)	C17—C18—C22	117.38 (11)
C4—O5—C6	121.54 (10)	N19—C18—C22	121.10 (12)
O5—C6—C7	117.73 (11)	C18—N19—C20	120.85 (12)
O5—C6—O8	116.75 (12)	C18—N19—C21	120.98 (13)
C7—C6—O8	125.52 (14)	C20—N19—C21	117.41 (13)
C6—C7—C2	120.70 (12)	N19—C20—H201	109.4
C6—C7—H71	116.9	N19—C20—H203	110.3
C2—C7—H71	122.4	H201—C20—H203	109.8
C4—C9—C10	118.74 (13)	N19—C20—H202	110.5
C4—C9—H91	119.3	H201—C20—H202	109.5
C10—C9—H91	121.9	H203—C20—H202	107.3
C9—C10—C11	120.87 (13)	N19—C21—H211	108.5
C9—C10—H101	120.4	N19—C21—H213	110.0
C11—C10—H101	118.7	H211—C21—H213	109.9
C10—C11—C12	120.06 (13)	N19—C21—H212	110.5
C10—C11—H111	120.8	H211—C21—H212	109.4
C12—C11—H111	119.2	H213—C21—H212	108.5
C3—C12—C11	120.37 (12)	C18—C22—C23	120.82 (12)
C3—C12—H121	118.8	C18—C22—H221	119.6
C11—C12—H121	120.8	C23—C22—H221	119.6
O1—C13—O14	122.43 (11)	C15—C23—C22	121.45 (12)
O1—C13—C15	110.44 (10)	C15—C23—H231	118.7
O14—C13—C15	127.08 (12)	C22—C23—H231	119.9
C13—C15—C16	118.18 (11)

Hydrogen-bond geometry (Å, º) top

Cg3 is the centroid of the benzoate-benzene ring (C15–C18/C22/C23).

D—H···A	D—H	H···A	D···A	D—H···A
C9—H91···O8ⁱ	0.96	2.49	3.449 (2)	171
C7—H71···Cg3ⁱⁱ	0.95	2.84	3.429 (2)	121
C20—H202···Cg3ⁱⁱⁱ	0.99	2.91	3.777 (2)	146

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

Experimental details

Crystal data
Chemical formula	C₁₈H₁₅NO₄
M_r	309.32
Crystal system, space group	Triclinic, P1
Temperature (K)	298
a, b, c (Å)	7.4939 (2), 10.2361 (3), 10.6620 (3)
α, β, γ (°)	92.307 (3), 103.935 (1), 109.852 (2)
V (Å³)	739.92 (4)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	0.10
Crystal size (mm)	0.50 × 0.40 × 0.30

Data collection
Diffractometer	Nonius KappaCCD diffractometer
Absorption correction	–
No. of measured, independent and observed [I > 2σ(I)] reflections	8424, 3590, 2897
R_int	0.024
(sin θ/λ)_max (Å⁻¹)	0.676

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.048, 0.120, 0.98
No. of reflections	3585
No. of parameters	208
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.23, −0.20

Computer programs: COLLECT (Nonius, 2001), DENZO/SCALEPACK (Otwinowski & Minor, 1997), SIR92 (Altomare et al., 1994), CRYSTALS (Betteridge et al., 2003), PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top

Cg3 is the centroid of the benzoate-benzene ring (C15–C18/C22/C23).

D—H···A	D—H	H···A	D···A	D—H···A
C9—H91···O8ⁱ	0.96	2.49	3.449 (2)	171
C7—H71···Cg3ⁱⁱ	0.95	2.84	3.429 (2)	121
C20—H202···Cg3ⁱⁱⁱ	0.99	2.91	3.777 (2)	146

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

Acknowledgements

We thank the Laboratoire de Physique des Interactions Ioniques and Spectropôle, Université de Provence, and the Université Paul Cézanne, Faculté des Sciences et Techniques de Saint Jérôme, Marseille, France, for the use of their diffractometer.

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