Ethyl 2-[(2-oxo-2H-chromen-7-yl)­oxy]acetate

Fun, H.-K.; Quah, C.K.; Aich, K.; Das, S.; Goswami, S.

doi:10.1107/S1600536813005539

organic compounds

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ISSN: 2056-9890

Volume 69| Part 4| April 2013| Page o502

doi:10.1107/S1600536813005539

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Ethyl 2-[(2-oxo-2H-chromen-7-yl)oxy]acetate

Hoong-Kun Fun,^a,^b ^*‡ Ching Kheng Quah,^a § Krishnendu Aich,^c Sangita Das ^c and Shyamaprosad Goswami ^c

^aX-ray Crystallography Unit, School of Physics, Universiti Sains Malaysia, 11800 USM, Penang, Malaysia, ^bDepartment of Pharmaceutical Chemistry, College of Pharmacy, King Saud University, PO Box 2457, Riyadh 11451, Saudi Arabia, and ^cDepartment of Chemistry, Bengal Engineering and Science University, Shibpur, Howrah 711 103, India
^*Correspondence e-mail: hkfun@usm.my

(Received 20 February 2013; accepted 26 February 2013; online 6 March 2013)

In the title compound, C₁₃H₁₂O₅, the mean plane of the 2H-chromene ring system (r.m.s deviation = 0.026 Å) forms a dihedral angle of 81.71 (6)° with the mean plane of ethyl 2-hydroxyacetate moiety (r.m.s deviation = 0.034 Å). In the crystal, C—H⋯O hydrogen bonds result in the formation of zigzag layers parallel to the bc plane.

Related literature

For general background to and the high emission quantum yield, photo stability and good solubility in common solvents of coumarin derivatives, see: Xie et al. (2012 ); Liu et al. (2012 ). For standard bond-length data, see: Allen et al. (1987 ). For the stability of the temperature controller used for the data collection, see: Cosier & Glazer (1986 ). For related structures, see: Arshad et al. (2010a ,b ).

Experimental

Crystal data

C₁₃H₁₂O₅
M_r = 248.23
Monoclinic, P 2₁ /c
a = 8.1435 (2) Å
b = 16.4887 (4) Å
c = 10.5506 (3) Å
β = 125.882 (2)°
V = 1147.84 (5) Å³
Z = 4
Mo Kα radiation
μ = 0.11 mm⁻¹
T = 100 K
0.31 × 0.24 × 0.11 mm

Data collection

Bruker SMART APEXII CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2009 ) T_min = 0.966, T_max = 0.988
12656 measured reflections
3344 independent reflections
2308 reflections with I > 2σ(I)
R_int = 0.035

Refinement

R[F² > 2σ(F²)] = 0.049
wR(F²) = 0.114
S = 1.04
3344 reflections
164 parameters
H-atom parameters constrained
Δρ_max = 0.32 e Å⁻³
Δρ_min = −0.24 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C1—H1A⋯O2ⁱ	0.93	2.38	3.2913 (19)	166
C5—H5A⋯O5ⁱⁱ	0.93	2.55	3.373 (2)	147
C10—H10B⋯O2ⁱ	0.97	2.48	3.353 (2)	149
Symmetry codes: (i) $[x, -y+{\script{3\over 2}}, z+{\script{1\over 2}}]$ ; (ii) -x, -y+2, -z.

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008 ); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL and PLATON (Spek, 2009 ).

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536813005539/rz5046sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536813005539/rz5046Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536813005539/rz5046Isup3.cml

checkCIF report

Comment top

Coumarins are attractive fluorescent molecules due to their high emission quantum yield, photo stability and good solubility in common solvents. As a consequence of these features, coumarins are widely used as laser dyes (Xie et al., 2012; Liu et al., 2012). Herein, we report the crystal structure of ethyl 2-(2-oxo-2H-chromen-7-yloxy)acetate.

In the title molecule, Fig. 1, the mean plane of 2H-chromene ring system (O1/C1-C9, r.m.s deviation = 0.026 Å) forms a dihedral angle of 81.71 (6)° with the mean plane of ethyl 2-hydroxyacetate moiety (O1/N3/C9/C10, r.m.s deviation = 0.034 Å). Bond lengths (Allen et al., 1987) and angles are within normal ranges and are comparable to those observed in related structures (Arshad et al., 2010a, 2010b).

In the crystal structure (Fig. 2), molecules are linked via intermolecular C1–H1A···O2, C5–H5A···O5 and C10–H10B···O2 hydrogen bonds (Table 1) into zigzag layers parallel to the bc plane.

Related literature top

For general background to and the high emission quantum yield, photo stability and good solubility in common solvents of coumarin derivatives, see: Xie et al. (2012); Liu et al. (2012). For standard bond-length data, see: Allen et al. (1987). For the stability of the temperature controller used for the data collection, see: Cosier & Glazer (1986). For related structures, see: Arshad et al. (2010a,b).

Experimental top

To a stirred solution of 7-hydroxycoumarin (500 mg, 3 mmol) in dry acetone, potassium carbonate (900 mg, 6 mmol) was added. After stirring for five minutes, ethyl chloroacetate (564 mg, 4.6 mmol) and a catalytic amount of TBAB were added to it. The whole reaction mixture was further stirred for 12 h at room temperature. After evaporation, water was added to it and the reaction mixture was extracted with chloroform thrice. The organic solvents were combined together and dried over anhydrous sodium sulphate and evaporated under reduced pressure. The crude product was purified through column chromatography (silica gel, 100-200 mesh size) using 15% ethyl acetate in petroleum ether as eluent to afford a pure colourless crystalline solid. Yield: 98%. M. p. 74-76 °C.

Computing details top

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).

Figures top

	Fig. 1. The molecular structure of the title compound showing 50% probability displacement ellipsoids for non-H atoms.
	Fig. 2. The crystal structure of the title compound, viewed along the c axis. H atoms not involved in hydrogen bonds (dashed lines) have been omitted for clarity.

Ethyl 2-[(2-oxo-2H-chromen-7-yl)oxy]acetate top

Crystal data top

C₁₃H₁₂O₅	F(000) = 520
M_r = 248.23	D_x = 1.436 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 3372 reflections
a = 8.1435 (2) Å	θ = 2.5–29.4°
b = 16.4887 (4) Å	µ = 0.11 mm⁻¹
c = 10.5506 (3) Å	T = 100 K
β = 125.882 (2)°	Block, colourless
V = 1147.84 (5) Å³	0.31 × 0.24 × 0.11 mm
Z = 4

Data collection top

Bruker SMART APEXII CCD area-detector diffractometer	3344 independent reflections
Radiation source: fine-focus sealed tube	2308 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.035
ϕ and ω scans	θ_max = 30.0°, θ_min = 2.5°
Absorption correction: multi-scan (SADABS; Bruker, 2009)	h = −9→11
T_min = 0.966, T_max = 0.988	k = −23→15
12656 measured 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)] = 0.049	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.114	H-atom parameters constrained
S = 1.04	w = 1/[σ²(F_o²) + (0.040P)² + 0.4605P] where P = (F_o² + 2F_c²)/3
3344 reflections	(Δ/σ)_max = 0.001
164 parameters	Δρ_max = 0.32 e Å⁻³
0 restraints	Δρ_min = −0.24 e Å⁻³

Crystal data top

C₁₃H₁₂O₅	V = 1147.84 (5) Å³
M_r = 248.23	Z = 4
Monoclinic, P2₁/c	Mo Kα radiation
a = 8.1435 (2) Å	µ = 0.11 mm⁻¹
b = 16.4887 (4) Å	T = 100 K
c = 10.5506 (3) Å	0.31 × 0.24 × 0.11 mm
β = 125.882 (2)°

Data collection top

Bruker SMART APEXII CCD area-detector diffractometer	3344 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2009)	2308 reflections with I > 2σ(I)
T_min = 0.966, T_max = 0.988	R_int = 0.035
12656 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.049	0 restraints
wR(F²) = 0.114	H-atom parameters constrained
S = 1.04	Δρ_max = 0.32 e Å⁻³
3344 reflections	Δρ_min = −0.24 e Å⁻³
164 parameters

Special details top

Experimental. The crystal was placed in the cold stream of an Oxford Cryosystems Cobra open-flow nitrogen cryostat (Cosier & Glazer, 1986) operating at 100.0 (1) K.

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

	x	y	z	U_iso*/U_eq
O1	0.39589 (16)	0.81519 (6)	0.17293 (12)	0.0225 (2)
O2	0.48206 (18)	0.71922 (7)	0.07680 (13)	0.0311 (3)
O3	0.23054 (17)	1.01606 (6)	0.40644 (13)	0.0273 (3)
O4	0.06112 (16)	0.85696 (7)	0.53551 (13)	0.0284 (3)
O5	−0.09962 (17)	0.91734 (7)	0.30015 (13)	0.0305 (3)
C1	0.3155 (2)	0.91211 (9)	0.29088 (17)	0.0211 (3)
H1A	0.3389	0.8732	0.3635	0.025*
C2	0.3385 (2)	0.89394 (9)	0.17359 (16)	0.0193 (3)
C3	0.4238 (2)	0.78861 (10)	0.06252 (18)	0.0246 (3)
C4	0.3788 (2)	0.84577 (10)	−0.05922 (18)	0.0268 (3)
H4A	0.3890	0.8291	−0.1386	0.032*
C5	0.3227 (2)	0.92215 (10)	−0.05837 (18)	0.0270 (3)
H5A	0.2957	0.9579	−0.1367	0.032*
C6	0.3039 (2)	0.94961 (9)	0.06176 (17)	0.0221 (3)
C7	0.2475 (2)	1.02864 (10)	0.07243 (18)	0.0254 (3)
H7A	0.2248	1.0677	0.0001	0.031*
C8	0.2255 (2)	1.04899 (9)	0.18806 (18)	0.0243 (3)
H8A	0.1900	1.1016	0.1947	0.029*
C9	0.2567 (2)	0.98993 (9)	0.29621 (17)	0.0225 (3)
C10	0.2416 (2)	0.95782 (10)	0.51046 (18)	0.0253 (3)
H10A	0.2669	0.9853	0.6017	0.030*
H10B	0.3541	0.9213	0.5454	0.030*
C11	0.0474 (2)	0.90906 (9)	0.43309 (17)	0.0232 (3)
C12	−0.1214 (2)	0.80927 (10)	0.4789 (2)	0.0301 (4)
H12A	−0.1582	0.7776	0.3882	0.036*
H12B	−0.2336	0.8449	0.4489	0.036*
C13	−0.0765 (3)	0.75434 (11)	0.6084 (2)	0.0381 (4)
H13A	−0.1945	0.7226	0.5743	0.057*
H13B	−0.0400	0.7862	0.6975	0.057*
H13C	0.0337	0.7190	0.6365	0.057*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O1	0.0289 (6)	0.0198 (5)	0.0218 (5)	0.0002 (4)	0.0166 (5)	0.0001 (4)
O2	0.0396 (7)	0.0241 (6)	0.0342 (6)	−0.0001 (5)	0.0243 (6)	−0.0039 (5)
O3	0.0382 (6)	0.0211 (6)	0.0293 (6)	−0.0009 (5)	0.0236 (5)	−0.0021 (5)
O4	0.0249 (6)	0.0342 (6)	0.0231 (5)	−0.0025 (5)	0.0125 (5)	0.0046 (5)
O5	0.0309 (6)	0.0332 (7)	0.0220 (6)	0.0021 (5)	0.0125 (5)	0.0023 (5)
C1	0.0242 (7)	0.0208 (7)	0.0189 (7)	−0.0017 (6)	0.0129 (6)	0.0021 (6)
C2	0.0181 (7)	0.0183 (7)	0.0185 (7)	−0.0015 (5)	0.0091 (6)	−0.0009 (5)
C3	0.0237 (7)	0.0282 (9)	0.0227 (8)	−0.0039 (6)	0.0140 (7)	−0.0054 (6)
C4	0.0269 (8)	0.0334 (9)	0.0218 (8)	−0.0023 (7)	0.0152 (7)	−0.0011 (7)
C5	0.0268 (8)	0.0342 (9)	0.0203 (7)	−0.0013 (7)	0.0139 (7)	0.0047 (7)
C6	0.0191 (7)	0.0263 (8)	0.0183 (7)	−0.0021 (6)	0.0095 (6)	0.0021 (6)
C7	0.0237 (7)	0.0246 (8)	0.0255 (8)	−0.0001 (6)	0.0130 (7)	0.0067 (6)
C8	0.0242 (8)	0.0187 (8)	0.0285 (8)	−0.0008 (6)	0.0146 (7)	0.0006 (6)
C9	0.0232 (7)	0.0237 (8)	0.0216 (7)	−0.0036 (6)	0.0136 (6)	−0.0027 (6)
C10	0.0289 (8)	0.0270 (8)	0.0219 (7)	−0.0006 (7)	0.0160 (7)	−0.0016 (6)
C11	0.0280 (8)	0.0224 (8)	0.0213 (7)	0.0038 (6)	0.0156 (7)	0.0000 (6)
C12	0.0256 (8)	0.0314 (9)	0.0295 (8)	−0.0033 (7)	0.0142 (7)	−0.0025 (7)
C13	0.0324 (9)	0.0384 (10)	0.0474 (11)	0.0026 (8)	0.0257 (9)	0.0110 (9)

Geometric parameters (Å, º) top

O1—C2	1.3814 (17)	C5—H5A	0.9300
O1—C3	1.3827 (17)	C6—C7	1.408 (2)
O2—C3	1.2136 (19)	C7—C8	1.375 (2)
O3—C9	1.3692 (17)	C7—H7A	0.9300
O3—C10	1.4211 (18)	C8—C9	1.405 (2)
O4—C11	1.3328 (18)	C8—H8A	0.9300
O4—C12	1.4642 (19)	C10—C11	1.516 (2)
O5—C11	1.2045 (18)	C10—H10A	0.9700
C1—C9	1.382 (2)	C10—H10B	0.9700
C1—C2	1.389 (2)	C12—C13	1.495 (2)
C1—H1A	0.9300	C12—H12A	0.9700
C2—C6	1.387 (2)	C12—H12B	0.9700
C3—C4	1.456 (2)	C13—H13A	0.9600
C4—C5	1.341 (2)	C13—H13B	0.9600
C4—H4A	0.9300	C13—H13C	0.9600
C5—C6	1.436 (2)

C2—O1—C3	121.70 (12)	C9—C8—H8A	120.1
C9—O3—C10	118.20 (12)	O3—C9—C1	123.83 (13)
C11—O4—C12	115.63 (12)	O3—C9—C8	115.29 (13)
C9—C1—C2	117.86 (13)	C1—C9—C8	120.85 (14)
C9—C1—H1A	121.1	O3—C10—C11	111.63 (12)
C2—C1—H1A	121.1	O3—C10—H10A	109.3
O1—C2—C6	121.23 (13)	C11—C10—H10A	109.3
O1—C2—C1	115.48 (12)	O3—C10—H10B	109.3
C6—C2—C1	123.28 (14)	C11—C10—H10B	109.3
O2—C3—O1	116.08 (14)	H10A—C10—H10B	108.0
O2—C3—C4	126.72 (14)	O5—C11—O4	124.81 (15)
O1—C3—C4	117.20 (14)	O5—C11—C10	125.30 (14)
C5—C4—C3	120.84 (14)	O4—C11—C10	109.86 (12)
C5—C4—H4A	119.6	O4—C12—C13	107.85 (13)
C3—C4—H4A	119.6	O4—C12—H12A	110.1
C4—C5—C6	120.98 (14)	C13—C12—H12A	110.1
C4—C5—H5A	119.5	O4—C12—H12B	110.1
C6—C5—H5A	119.5	C13—C12—H12B	110.1
C2—C6—C7	117.25 (14)	H12A—C12—H12B	108.5
C2—C6—C5	117.92 (14)	C12—C13—H13A	109.5
C7—C6—C5	124.81 (14)	C12—C13—H13B	109.5
C8—C7—C6	121.00 (14)	H13A—C13—H13B	109.5
C8—C7—H7A	119.5	C12—C13—H13C	109.5
C6—C7—H7A	119.5	H13A—C13—H13C	109.5
C7—C8—C9	119.71 (14)	H13B—C13—H13C	109.5
C7—C8—H8A	120.1

C3—O1—C2—C6	0.8 (2)	C2—C6—C7—C8	−0.8 (2)
C3—O1—C2—C1	179.82 (13)	C5—C6—C7—C8	177.46 (15)
C9—C1—C2—O1	−179.53 (12)	C6—C7—C8—C9	−0.9 (2)
C9—C1—C2—C6	−0.6 (2)	C10—O3—C9—C1	−7.5 (2)
C2—O1—C3—O2	177.16 (13)	C10—O3—C9—C8	174.34 (13)
C2—O1—C3—C4	−3.51 (19)	C2—C1—C9—O3	−179.32 (13)
O2—C3—C4—C5	−177.40 (16)	C2—C1—C9—C8	−1.3 (2)
O1—C3—C4—C5	3.4 (2)	C7—C8—C9—O3	−179.80 (13)
C3—C4—C5—C6	−0.5 (2)	C7—C8—C9—C1	2.0 (2)
O1—C2—C6—C7	−179.50 (13)	C9—O3—C10—C11	−78.32 (16)
C1—C2—C6—C7	1.6 (2)	C12—O4—C11—O5	−1.9 (2)
O1—C2—C6—C5	2.1 (2)	C12—O4—C11—C10	176.37 (12)
C1—C2—C6—C5	−176.81 (14)	O3—C10—C11—O5	0.2 (2)
C4—C5—C6—C2	−2.2 (2)	O3—C10—C11—O4	−178.06 (12)
C4—C5—C6—C7	179.51 (15)	C11—O4—C12—C13	179.49 (14)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C1—H1A···O2ⁱ	0.93	2.38	3.2913 (19)	166
C5—H5A···O5ⁱⁱ	0.93	2.55	3.373 (2)	147
C10—H10B···O2ⁱ	0.97	2.48	3.353 (2)	149

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

Experimental details

Crystal data
Chemical formula	C₁₃H₁₂O₅
M_r	248.23
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	100
a, b, c (Å)	8.1435 (2), 16.4887 (4), 10.5506 (3)
β (°)	125.882 (2)
V (Å³)	1147.84 (5)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.11
Crystal size (mm)	0.31 × 0.24 × 0.11

Data collection
Diffractometer	Bruker SMART APEXII CCD area-detector diffractometer
Absorption correction	Multi-scan (SADABS; Bruker, 2009)
T_min, T_max	0.966, 0.988
No. of measured, independent and observed [I > 2σ(I)] reflections	12656, 3344, 2308
R_int	0.035
(sin θ/λ)_max (Å⁻¹)	0.704

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.049, 0.114, 1.04
No. of reflections	3344
No. of parameters	164
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.32, −0.24

Computer programs: APEX2 (Bruker, 2009), SAINT (Bruker, 2009), SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C1—H1A···O2ⁱ	0.9300	2.3800	3.2913 (19)	166.00
C5—H5A···O5ⁱⁱ	0.9300	2.5500	3.373 (2)	147.00
C10—H10B···O2ⁱ	0.9700	2.4800	3.353 (2)	149.00

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

Footnotes

‡Thomson Reuters ResearcherID: A-3561-2009.

§Thomson Reuters ResearcherID: A-5525-2009.

Acknowledgements

The authors thank Universiti Sains Malaysia (USM) for the RUC grant (Structure Determination of 50 kDa Outer Membrane Proteins from S. typhi by X-ray Protein Crystallography, No. 1001/PSKBP/8630013) and APEX DE2012 grant (No.1002/PFIZIK/910323). The authors also thank the CSIR and DST, Government of India, for financial support.

References

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