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organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 66| Part 6| June 2010| Page o1310
https://doi.org/10.1107/S1600536810016193

Ethyl 4-(2-fur­yl)-2-oxochroman-3-carboxyl­ate

Maddela Prabhakar,a J. S. N. Reddy,a N. Ravi Kumar,a S. Viswanadha Ganesha and K. Anand Solomona*

aInstitute of Life Sciences, University of Hyderabad Campus, Hyderabad 500 046, India
*Correspondence e-mail: anandsolomonk@ilsresearch.org

(Received 15 April 2010; accepted 3 May 2010; online 12 May 2010)

The title compound, C16H14O5, was prepared from the reaction of 3-carbethoxy­coumarin with furan in the presence of AlCl3 as catalyst. In the crystal, inter­molecular C—H⋯O hydrogen-bonding inter­actions between four mol­ecules lead to a tetra­mer in the unit cell. The furan ring is anti­periplanar [C—C—C—O = 167.9 (13)°] and the ethoxy­carbonyl group is (−)anti­clinal [C—C—C—O = −128.6 (14)°] to the lactone ring.

Related literature

For the medicinal and biological activity of coumarins and their derivatives, see: Borges et al. (2005[Borges, F., Roleira, F., Milhazes, N., Santana, L. & Uriarte, E. (2005). Curr. Med. Chem. 12, 887-916.]); Kontogiorgis & Hadjipavlou-Litina (2005[Kontogiorgis, C. A. & Hadjipavlou-Litina, D. J. (2005). J. Med. Chem. 48, 6400-6408.]); Gursoy & Karali (2003[Gursoy, A. & &Karali, N. (2003). Turk. J. Chem. 27, 545-551.]); Prabhakar et al. (2010[Prabhakar, M., Narendar Reddy, G., Srinu, G., Manjulatha, K., Venkata Prasad, J., Pramod Kumar, S., Srinivas, O., Iqbal, J. & Anil Kumar, K. (2010). Synlett, pp. 947-951.]). For the assignment of conformations and the orientation of the substituents, see: Nardelli (1983[Nardelli, M. (1983). Acta Cryst. C39, 1141-1142.], 1995[Nardelli, M. (1995). J. Appl. Cryst. 28, 659.]); Klyne & Prelog (1960[Klyne, W. & Prelog, V. (1960). Experientia, 16, 521-568.]).

[Scheme 1]

Experimental

Crystal data

  • C16H14O5

  • Mr = 286.27

  • Monoclinic, P 21 /c

  • a = 10.393 (3) Å

  • b = 8.459 (3) Å

  • c = 15.819 (5) Å

  • β = 95.464 (5)°

  • V = 1384.5 (8) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.10 mm−1

  • T = 298 K

  • 0.34 × 0.24 × 0.20 mm
Data collection

  • Bruker SMART CCD area-detector diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2003[Bruker (2003). SMART, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.966, Tmax = 0.980

  • 13767 measured reflections

  • 2711 independent reflections

  • 2099 reflections with I > 2σ(I)

  • Rint = 0.035
Refinement

  • R[F2 > 2σ(F2)] = 0.042

  • wR(F2) = 0.111

  • S = 1.04

  • 2711 reflections

  • 227 parameters

  • H atoms treated by a mixture of independent and constrained refinement

  • Δρmax = 0.18 e Å−3

  • Δρmin = −0.16 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A D⋯A D—H⋯A
C3—H3⋯O3i 0.972 (15) 2.696 (15) 3.576 (2) 150.8 (11)
C16—H16B⋯O2ii 0.96 2.70 3.549 (3) 148
C16—H16A⋯O2iii 0.96 2.96 3.841 (3) 153
C8—H8⋯O3iv 0.96 (2) 2.94 (2) 3.611 (3) 128.2 (15)
C11—H11⋯O4v 0.93 (2) 2.73 (2) 3.501 (3) 140.9 (17)
C13—H13⋯O2vi 1.01 (2) 2.54 (2) 3.456 (3) 151.0 (17)
C12—H12⋯O4vii 0.95 (2) 2.74 (2) 3.478 (3) 134.9 (16)
Symmetry codes: (i) -x+1, -y+2, -z+2; (ii) x, y-1, z; (iii) [-x+2, y-{\script{1\over 2}}, -z+{\script{3\over 2}}]; (iv) -x+2, -y+2, -z+2; (v) [-x+1, y+{\script{1\over 2}}, -z+{\script{3\over 2}}]; (vi) [x, -y+{\script{5\over 2}}, z+{\script{1\over 2}}]; (vii) x, y+1, z.

Data collection: SMART (Bruker, 2003[Bruker (2003). SMART, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2003[Bruker (2003). SMART, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); software used to prepare material for publication: SHELXTL.

Supporting information

Crystal structure: contains datablocks I, global. DOI: https://doi.org/10.1107/S1600536810016193/ds2028sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536810016193/ds2028Isup2.hkl

checkCIF report


Comment top

We have synthesized and reported our serendipitous observations on the Diels-Alder reaction of 3-carbethoxy coumarin with furan, followed by a ring opening to yield Michael product, 3-carbethoxy-4-(2-furyl)-chroman-2-one in good yields.

Related literature top

For the medicinal and biological activity of coumarins and their derivatives, see: Borges et al. (2005); Kontogiorgis & Hadjipavlou-Litina (2005); Gursoy & Karali (2003); Prabhakar et al. (2010). For the assignment of conformations and the orientation of the substituents, see: Nardelli (1983, 1995); Klyne & Prelog (1960).

Experimental top

3-Carbethoxy coumarin (3 m mol) was taken into 30 mmol of furan and 10 mol% of AlCl3 catalyst was added. The reaction mixture was stirred at room temperature for 24 hours. After completion of the reaction, the excess of the furan was distilled off and extracted thrice with water/dichloromethane. The product was separated from flash column chromatography and recrystallized from dichloromethane.

Refinement top

All H atoms were found on difference maps, with C—H=0.93 Å and included in the final cycles of refinement using a riding model, with Uiso(H)=1.2Ueq(C)

Structure description top

We have synthesized and reported our serendipitous observations on the Diels-Alder reaction of 3-carbethoxy coumarin with furan, followed by a ring opening to yield Michael product, 3-carbethoxy-4-(2-furyl)-chroman-2-one in good yields.

For the medicinal and biological activity of coumarins and their derivatives, see: Borges et al. (2005); Kontogiorgis & Hadjipavlou-Litina (2005); Gursoy & Karali (2003); Prabhakar et al. (2010). For the assignment of conformations and the orientation of the substituents, see: Nardelli (1983, 1995); Klyne & Prelog (1960).

Computing details top

Data collection: SMART (Bruker, 2003); cell refinement: SAINT (Bruker, 2003); data reduction: SAINT (Bruker, 2003); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. Chemical diagram of the title compound.
[Figure 2] Fig. 2. ORTEP diagram of the 3-carbethoxy-4-(2-furyl)-chroman-2-one. (Thermal ellipsoids are at 50% probability level).
[Figure 3] Fig. 3. Crystal packing of (I) showing the formation of tetramer. The C—H•••O contacts are shown as dashed lines. Symmetry code: (i) 1-x,-1/2+y, 1/2-z (ii) x, -1/2-y, -1/2+z
[Figure 4] Fig. 4. The formation of the title compound.
Ethyl 4-(2-furyl)-2-oxochroman-3-carboxylate top
Crystal data top
C16H14O5F(000) = 600
Mr = 286.27Dx = 1.373 Mg m−3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 5174 reflections
a = 10.393 (3) Åθ = 2.5–25.8°
b = 8.459 (3) ŵ = 0.10 mm−1
c = 15.819 (5) ÅT = 298 K
β = 95.464 (5)°Block, colourless
V = 1384.5 (8) Å30.34 × 0.24 × 0.20 mm
Z = 4
Data collection top
Bruker SMART CCD area-detector
diffractometer		2711 independent reflections
Radiation source: fine-focus sealed tube2099 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.035
phi and ω scansθmax = 25.9°, θmin = 2.0°
Absorption correction: multi-scan
(SADABS; Bruker, 2003)		h = −12→12
Tmin = 0.966, Tmax = 0.980k = −10→10
13767 measured reflectionsl = −19→19
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.042Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.111H atoms treated by a mixture of independent and constrained refinement
S = 1.04 w = 1/[σ2(Fo2) + (0.058P)2 + 0.1619P]
where P = (Fo2 + 2Fc2)/3
2711 reflections(Δ/σ)max < 0.001
227 parametersΔρmax = 0.18 e Å−3
0 restraintsΔρmin = −0.16 e Å−3
Crystal data top
C16H14O5V = 1384.5 (8) Å3
Mr = 286.27Z = 4
Monoclinic, P21/cMo Kα radiation
a = 10.393 (3) ŵ = 0.10 mm−1
b = 8.459 (3) ÅT = 298 K
c = 15.819 (5) Å0.34 × 0.24 × 0.20 mm
β = 95.464 (5)°
Data collection top
Bruker SMART CCD area-detector
diffractometer		2711 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2003)		2099 reflections with I > 2σ(I)
Tmin = 0.966, Tmax = 0.980Rint = 0.035
13767 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0420 restraints
wR(F2) = 0.111H atoms treated by a mixture of independent and constrained refinement
S = 1.04Δρmax = 0.18 e Å−3
2711 reflectionsΔρmin = −0.16 e Å−3
227 parameters
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
H20.5893 (16)0.9788 (19)0.7769 (10)0.045 (4)*
H130.648 (2)1.325 (3)1.0884 (14)0.084 (7)*
H110.598 (2)1.251 (2)0.8313 (14)0.076 (6)*
H120.598 (2)1.472 (3)0.9435 (13)0.081 (6)*
H71.082 (2)0.672 (3)1.0318 (14)0.085 (7)*
H60.8933 (19)0.630 (2)1.0962 (13)0.073 (6)*
H81.077 (2)0.828 (2)0.9093 (13)0.078 (6)*
H50.6973 (18)0.7462 (19)1.0400 (11)0.048 (5)*
H30.5753 (15)0.8783 (17)0.9186 (9)0.033 (4)*
C60.8921 (2)0.6956 (2)1.04771 (12)0.0626 (5)
O30.65502 (12)1.13244 (14)1.01627 (7)0.0545 (3)
O10.88812 (11)0.98037 (14)0.83531 (7)0.0523 (3)
O50.74734 (13)0.71312 (14)0.73664 (7)0.0598 (4)
O20.78518 (13)1.08381 (15)0.72090 (7)0.0635 (4)
C30.65067 (15)0.93666 (18)0.90397 (9)0.0404 (4)
O40.57089 (13)0.66307 (15)0.80304 (8)0.0651 (4)
C40.77275 (15)0.86004 (17)0.94453 (9)0.0388 (4)
C10.77894 (17)1.00313 (19)0.78254 (10)0.0460 (4)
C90.88546 (15)0.88312 (18)0.90688 (10)0.0429 (4)
C20.65772 (16)0.92533 (19)0.80739 (10)0.0425 (4)
C140.65204 (17)0.7516 (2)0.78227 (10)0.0465 (4)
C130.63873 (19)1.2923 (2)1.02691 (14)0.0597 (5)
C81.00056 (18)0.8154 (2)0.93811 (12)0.0576 (5)
C50.77720 (19)0.7640 (2)1.01532 (10)0.0502 (4)
C100.63742 (14)1.10518 (19)0.93083 (9)0.0419 (4)
C110.61161 (18)1.2410 (2)0.89003 (12)0.0550 (5)
C120.61250 (19)1.3618 (2)0.95281 (13)0.0593 (5)
C150.7673 (2)0.5456 (2)0.71929 (12)0.0718 (6)
H15A0.80290.53390.66520.086*
H15B0.68530.49020.71620.086*
C71.0035 (2)0.7225 (2)1.00924 (13)0.0656 (5)
C160.8571 (2)0.4771 (2)0.78765 (14)0.0738 (6)
H16A0.93560.53760.79350.111*
H16B0.87630.36980.77370.111*
H16C0.81770.47950.84010.111*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C60.0812 (15)0.0569 (11)0.0475 (10)0.0109 (10)−0.0047 (10)0.0124 (9)
O30.0658 (8)0.0534 (7)0.0449 (7)0.0049 (6)0.0093 (5)−0.0084 (5)
O10.0463 (7)0.0581 (7)0.0526 (7)−0.0034 (5)0.0059 (5)0.0137 (6)
O50.0819 (9)0.0466 (7)0.0524 (7)0.0094 (6)0.0151 (7)−0.0060 (5)
O20.0824 (9)0.0614 (8)0.0474 (7)0.0061 (7)0.0110 (6)0.0171 (6)
C30.0377 (8)0.0423 (9)0.0416 (8)−0.0022 (7)0.0052 (7)−0.0030 (7)
O40.0666 (8)0.0592 (8)0.0684 (9)−0.0165 (7)0.0007 (7)−0.0116 (6)
C40.0459 (9)0.0342 (8)0.0357 (8)−0.0005 (6)0.0000 (6)−0.0043 (6)
C10.0571 (10)0.0409 (9)0.0403 (9)0.0072 (7)0.0058 (8)0.0004 (7)
C90.0453 (9)0.0417 (8)0.0410 (8)−0.0012 (7)0.0005 (7)0.0016 (7)
C20.0446 (9)0.0423 (9)0.0392 (8)0.0078 (7)−0.0041 (7)−0.0021 (7)
C140.0539 (10)0.0482 (9)0.0352 (8)0.0012 (8)−0.0077 (7)−0.0034 (7)
C130.0629 (12)0.0556 (11)0.0622 (12)−0.0001 (9)0.0144 (10)−0.0197 (10)
C80.0456 (10)0.0652 (12)0.0609 (11)0.0047 (8)−0.0008 (9)0.0030 (9)
C50.0623 (11)0.0471 (10)0.0420 (9)−0.0002 (8)0.0081 (8)0.0010 (8)
C100.0384 (8)0.0479 (9)0.0394 (8)0.0024 (7)0.0044 (6)−0.0057 (7)
C110.0628 (12)0.0512 (10)0.0508 (11)0.0106 (8)0.0039 (9)−0.0008 (9)
C120.0629 (12)0.0441 (10)0.0723 (13)0.0059 (9)0.0138 (10)−0.0066 (9)
C150.1093 (17)0.0474 (11)0.0597 (12)0.0141 (11)0.0133 (12)−0.0108 (9)
C70.0622 (13)0.0673 (13)0.0641 (12)0.0171 (10)−0.0104 (10)0.0071 (10)
C160.0813 (15)0.0552 (11)0.0863 (15)0.0111 (10)0.0158 (12)0.0064 (11)
Geometric parameters (Å, º) top
C6—C71.377 (3)C2—C141.522 (2)
C6—C51.381 (3)C2—H20.937 (17)
C6—H60.94 (2)C13—C121.317 (3)
O3—C101.3663 (19)C13—H131.01 (2)
O3—C131.375 (2)C8—C71.371 (3)
O1—C11.357 (2)C8—H80.96 (2)
O1—C91.4020 (19)C5—H50.962 (18)
O5—C141.321 (2)C10—C111.333 (2)
O5—C151.462 (2)C11—C121.425 (3)
O2—C11.1969 (19)C11—H110.93 (2)
C3—C101.498 (2)C12—H120.95 (2)
C3—C41.512 (2)C15—C161.478 (3)
C3—C21.539 (2)C15—H15A0.9700
C3—H30.972 (15)C15—H15B0.9700
O4—C141.197 (2)C7—H70.95 (2)
C4—C91.378 (2)C16—H16A0.9600
C4—C51.381 (2)C16—H16B0.9600
C1—C21.506 (2)C16—H16C0.9600
C9—C81.375 (2)
C7—C6—C5120.05 (18)O3—C13—H13113.0 (13)
C7—C6—H6120.5 (13)C7—C8—C9118.97 (19)
C5—C6—H6119.4 (13)C7—C8—H8119.9 (13)
C10—O3—C13106.29 (14)C9—C8—H8121.0 (13)
C1—O1—C9120.03 (12)C6—C5—C4120.55 (18)
C14—O5—C15117.97 (15)C6—C5—H5122.2 (10)
C10—C3—C4112.56 (13)C4—C5—H5117.2 (10)
C10—C3—C2110.80 (13)C11—C10—O3109.59 (14)
C4—C3—C2106.09 (12)C11—C10—C3134.68 (15)
C10—C3—H3108.5 (8)O3—C10—C3115.73 (13)
C4—C3—H3110.1 (8)C10—C11—C12107.06 (17)
C2—C3—H3108.7 (8)C10—C11—H11124.6 (13)
C9—C4—C5118.03 (15)C12—C11—H11128.3 (13)
C9—C4—C3117.99 (13)C13—C12—C11106.68 (17)
C5—C4—C3123.94 (15)C13—C12—H12126.2 (13)
O2—C1—O1118.36 (16)C11—C12—H12127.1 (13)
O2—C1—C2124.98 (16)O5—C15—C16109.51 (16)
O1—C1—C2116.65 (13)O5—C15—H15A109.8
C8—C9—C4122.14 (15)C16—C15—H15A109.8
C8—C9—O1116.82 (15)O5—C15—H15B109.8
C4—C9—O1121.02 (13)C16—C15—H15B109.8
C1—C2—C14111.48 (13)H15A—C15—H15B108.2
C1—C2—C3110.60 (13)C8—C7—C6120.24 (18)
C14—C2—C3108.36 (13)C8—C7—H7120.9 (14)
C1—C2—H2105.5 (10)C6—C7—H7118.8 (14)
C14—C2—H2108.9 (10)C15—C16—H16A109.5
C3—C2—H2112.1 (10)C15—C16—H16B109.5
O4—C14—O5125.46 (16)H16A—C16—H16B109.5
O4—C14—C2122.91 (16)C15—C16—H16C109.5
O5—C14—C2111.62 (15)H16A—C16—H16C109.5
C12—C13—O3110.37 (17)H16B—C16—H16C109.5
C12—C13—H13136.6 (13)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C3—H3···O3i0.972 (15)2.696 (15)3.576 (2)150.8 (11)
C16—H16B···O2ii0.962.703.549 (3)148
C16—H16A···O2iii0.962.963.841 (3)153
C8—H8···O3iv0.96 (2)2.94 (2)3.611 (3)128.2 (15)
C11—H11···O4v0.93 (2)2.73 (2)3.501 (3)140.9 (17)
C13—H13···O2vi1.01 (2)2.54 (2)3.456 (3)151.0 (17)
C12—H12···O4vii0.95 (2)2.74 (2)3.478 (3)134.9 (16)
Symmetry codes: (i) −x+1, −y+2, −z+2; (ii) x, y−1, z; (iii) −x+2, y−1/2, −z+3/2; (iv) −x+2, −y+2, −z+2; (v) −x+1, y+1/2, −z+3/2; (vi) x, −y+5/2, z+1/2; (vii) x, y+1, z.

Experimental details

Crystal data
Chemical formulaC16H14O5
Mr286.27
Crystal system, space groupMonoclinic, P21/c
Temperature (K)298
a, b, c (Å)10.393 (3), 8.459 (3), 15.819 (5)
β (°) 95.464 (5)
V (Å3)1384.5 (8)
Z4
Radiation typeMo Kα
µ (mm−1)0.10
Crystal size (mm)0.34 × 0.24 × 0.20
Data collection
DiffractometerBruker SMART CCD area-detector
Absorption correctionMulti-scan
(SADABS; Bruker, 2003)
Tmin, Tmax0.966, 0.980
No. of measured, independent and
observed [I > 2σ(I)] reflections		13767, 2711, 2099
Rint0.035
(sin θ/λ)max (Å−1)0.615
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.042, 0.111, 1.04
No. of reflections2711
No. of parameters227
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å−3)0.18, −0.16

Computer programs: SMART (Bruker, 2003), SAINT (Bruker, 2003), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C3—H3···O3i0.972 (15)2.696 (15)3.576 (2)150.8 (11)
C16—H16B···O2ii0.962.703.549 (3)147.6
C16—H16A···O2iii0.962.963.841 (3)153.4
C8—H8···O3iv0.96 (2)2.94 (2)3.611 (3)128.2 (15)
C11—H11···O4v0.93 (2)2.73 (2)3.501 (3)140.9 (17)
C13—H13···O2vi1.01 (2)2.54 (2)3.456 (3)151.0 (17)
C12—H12···O4vii0.95 (2)2.74 (2)3.478 (3)134.9 (16)
Symmetry codes: (i) −x+1, −y+2, −z+2; (ii) x, y−1, z; (iii) −x+2, y−1/2, −z+3/2; (iv) −x+2, −y+2, −z+2; (v) −x+1, y+1/2, −z+3/2; (vi) x, −y+5/2, z+1/2; (vii) x, y+1, z.
 

Acknowledgements

We thank the Director, Institute of Life Sciences, for support and also the Dean, School of Chemistry, University of Hyderabad, for the X-ray crystallographic data.

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ISSN: 2056-9890
Volume 66| Part 6| June 2010| Page o1310
https://doi.org/10.1107/S1600536810016193
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