Ethyl 2-(3-acetyl-6-methyl-2-oxo-2H-pyran-4-yl­oxy)acetate

Muhammad Rabnawaz; Stacy D Benson; Burhan Khan; Muhammad Raza Shah

doi:10.1107/S1600536810001601

. 2010 Jan 20;66(Pt 2):o397. doi: 10.1107/S1600536810001601

Ethyl 2-(3-acetyl-6-methyl-2-oxo-2H-pyran-4-yloxy)acetate

Muhammad Rabnawaz ^a, Stacy D Benson ^b, Burhan Khan ^a, Muhammad Raza Shah ^a,^*

PMCID: PMC2979740 PMID: 21579818

Abstract

The title compound, C₁₂H₁₄O₆, features a roughly planar molecule (r.m.s. deviation for all non-H atoms = 0.287 Å). In the crystal, the molecules are held together by C—H⋯O hydrogen bonds.

Related literature

For the use of dehydroacetic acid as a starting material in the synthesis of heterocyclic ring systems, see: Prakash et al. (2004 ▶), and of biologically important molecules such as coumarins, see: Hernandez-Galan et al. (1993 ▶).

Experimental

Crystal data

C₁₂H₁₄O₆
M _r = 254.23
Triclinic,
a = 7.8258 (10) Å
b = 8.2722 (11) Å
c = 10.0838 (13) Å
α = 77.374 (7)°
β = 77.759 (6)°
γ = 88.857 (7)°
V = 622.28 (14) Å³
Z = 2
Mo Kα radiation
μ = 0.11 mm⁻¹
T = 298 K
0.72 × 0.13 × 0.11 mm

Data collection

Bruker SMART APEXII diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2001 ▶) T _min = 0.925, T _max = 0.988
14279 measured reflections
3039 independent reflections
2330 reflections with I > 2σ(I)
R _int = 0.036

Refinement

R[F ² > 2σ(F ²)] = 0.050
wR(F ²) = 0.159
S = 1.04
3039 reflections
166 parameters
H-atom parameters constrained
Δρ_max = 0.35 e Å⁻³
Δρ_min = −0.20 e Å⁻³

Data collection: APEX2 (Bruker, 2008 ▶); cell refinement: SAINT-Plus (Bruker, 2008 ▶); data reduction: SAINT-Plus; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: XP in SHELXTL (Sheldrick, 2008 ▶); software used to prepare material for publication: SHELXL97.

Supplementary Material

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536810001601/bt5170sup1.cif

e-66-0o397-sup1.cif^{(17.4KB, cif)}

Structure factors: contains datablocks I. DOI: 10.1107/S1600536810001601/bt5170Isup2.hkl

e-66-0o397-Isup2.hkl^{(149.1KB, hkl)}

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Table 1. Hydrogen-bond geometry (Å, °).

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C6A—H6A1⋯O2ⁱ	0.96	2.53	3.462 (2)	165
C5—H5⋯O3Aⁱ	0.93	2.38	3.3053 (19)	174
C2A—H2A1⋯O3Aⁱ	0.97	2.57	3.355 (2)	138
C2E—H2E2⋯O1ⁱⁱ	0.96	2.54	3.484 (3)	169

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Symmetry codes: (i) Inline graphic ; (ii) .

Acknowledgments

The authors thank the Organization for the Prohibition of Chemical Weapons for financial support.

supplementary crystallographic information

Comment

3-Acetyl-4-hydroxy-6-methyl-2-oxo-2H-pyran (dehydroacetic acid) is a versatile starting material for the synthesis of a wide variety of heterocyclic ring systems (Prakash et al., 2004) and biologically important molecules like coumarins (Hernandez-Galan et al., 1993).

Experimental

The dehydroacetic acid (500 mg, 3 mmol) was treated with ethylbromoacetate (2 g, 12 mmol) in acetone in the presence of K₂CO₃ (1.6 g, 12 mmol). The reaction mixture was refluxed for 3 h monitored with TLC at regular intervals of 30 minutes. The reaction was quenched by addition of 1 N HCl (10 ml) and the aqueous layer was extracted with ethyl acetate three times. The combined organic layers were concentrated under reduced pressure. The crude residue was dissolved in hot ethanol. The slow evaporation of ethanol yielded colorless needle-like crystals (90%, 680 mg).