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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 68| Part 12| December 2012| Page o3379
doi:10.1107/S1600536812045606

2-(2-Hy­dr­oxy­propan-2-yl)-6-(prop-2-yn­yl­oxy)-1-benzo­furan-3(2H)-one

Henok H. Kinfe,a Yonas H. Belaya and Zanele H. Phashaa*

aResearch Center for Synthesis and Catalysis, Department of Chemistry, University of Johannesburg (APK Campus), PO Box 524, Auckland Park, Johannesburg, 2006, South Africa
*Correspondence e-mail: zhphasha@uj.ac.za

(Received 28 October 2012; accepted 5 November 2012; online 17 November 2012)

In the title compound, C14H14O4, the prop-2-yn­yloxy O—C—C≡C plane [maximum deviation = 0.0116 (12) Å] forms a dihedral angle of 78.44 (9)° with the benzofuran-3(2H)-one ring system. In the crystal, mol­ecules are linked by O—H⋯O hydrogen bonds, forming a tape along the a-axis direction. C—H⋯O inter­actions are observed between the tapes.

Related literature

For background to the development of hybrid drug candidates against tuberculosis, malaria and cancer, see: Morphy et al. (2004[Morphy, R., Kay, C. & Rankovic, Z. (2004). Drug Discov. Today, 9, 641-651.]). For details of the synthesis of the title compound, see: Hoogendoorn et al. (2011[Hoogendoorn, S., Blom, A. E. M., Willems, L. I., Van der Marel, G. A. & Overkleeft, H. S. (2011). Org. Lett. 13, 5656-5659.]).

[Scheme 1]

Experimental

Crystal data

  • C14H14O4

  • Mr = 246.25

  • Triclinic, [P \overline 1]

  • a = 5.4199 (2) Å

  • b = 9.0785 (3) Å

  • c = 12.3555 (4) Å

  • α = 85.758 (2)°

  • β = 80.455 (2)°

  • γ = 81.829 (2)°

  • V = 592.65 (4) Å3

  • Z = 2

  • Cu Kα radiation

  • μ = 0.84 mm−1

  • T = 100 K

  • 0.39 × 0.11 × 0.11 mm
Data collection

  • Bruker APEX DUO 4K CCD diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2008[Bruker (2008). SADABS and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.736, Tmax = 0.913

  • 10266 measured reflections

  • 1983 independent reflections

  • 1888 reflections with I > 2σ(I)

  • Rint = 0.025
Refinement

  • R[F2 > 2σ(F2)] = 0.032

  • wR(F2) = 0.082

  • S = 1.03

  • 1983 reflections

  • 166 parameters

  • H-atom parameters constrained

  • Δρmax = 0.21 e Å−3

  • Δρmin = −0.17 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A D⋯A D—H⋯A
O1—H⋯O4i 0.84 2.01 2.8328 (12) 167
C1—H1⋯O1ii 0.95 2.45 3.3283 (16) 154
C5—H5⋯O1iii 0.95 2.52 3.3809 (15) 152
Symmetry codes: (i) x+1, y, z; (ii) x, y, z-1; (iii) -x, -y+2, -z+1.

Data collection: APEX2 (Bruker, 2011[Bruker (2011). APEX2. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2008[Bruker (2008). SADABS and SAINT. 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: ORTEP-3 for Windows (Farrugia, 1997[Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565.]); software used to prepare material for publication: WinGX (Farrugia, 1999[Farrugia, L. J. (1999). J. Appl. Cryst. 32, 837-838.]).

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536812045606/is5212sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536812045606/is5212Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536812045606/is5212Isup3.cml

checkCIF report


Comment top

In our research in the development of hybrid drug candidates against tuberculosis, malaria and cancer (Morphy et al., 2004), the title compound was synthesized as a building starting material. The title compound was synthesized by the reaction of 6-hydroxy-benzofuran-3-one with propargyl bromide in the presence of potassium carbonate at relatively high temperature (Hoogendoorn et al., 2011). Herein we report the crystal structure of the title compound.

In the crystal structure of the title compound, the propyn-1-yloxy group (C1–C3/O3) forms a dihedral angle of 78.44 (9)° with the fused benzofuran-3-one ring system (Fig. 1). The crystal packing is stabilized by O—H···O interactions (Table 1 and Fig. 2). The C—H···O interactions are also observed (Table 1).

Related literature top

For background to the development of hybrid drug candidates against tuberculosis, malaria and cancer, see: Morphy et al. (2004). For details of the synthesis of the title compound, see: Hoogendoorn et al. (2011).

Experimental top

A solution of 6-hydroxy-benzofuran-3-one (1 g, 6.66 mmol) in dry acetone was treated with potassium carbonate (1.3 g, 9.32 mmol). The reaction mixture was heated at a temperature of 70–80 °C for about 30 minutes and then propargyl bromide (1.6 ml, 14.65 mmol) was added to it. The combined solution was stirred for about 2.5 h and concentrated under vacuum. The residue was diluted with water and extracted three times with ethyl acetate. The combined organic layer was washed with brine and water and dried over anhydrous magnesium sulfate. After that filtered and the filtrate solid product was recrystalized from ethyl acetate and hexane to afford 70% of the target compound as yellow crystal (m.p. 118–120 °C).

Refinement top

All hydrogen atoms were positioned in geometrically idealized positions with C—H = 1.00 Å (methine), 0.99 Å (methylene), 0.98 Å (methyl), 0.95 Å (aromatic), and 0.84 Å (hydroxyl). All hydrogen atoms were allowed to ride on their parent atoms with Uiso(H) = 1.2Ueq, except for the methyl and hydroxyl hydrogen atoms where Uiso(H) = 1.5Ueq was utilized. The initial positions of methyl hydrogen atoms were located in a difference Fourier map and refined as a fixed rotor.

Structure description top

In our research in the development of hybrid drug candidates against tuberculosis, malaria and cancer (Morphy et al., 2004), the title compound was synthesized as a building starting material. The title compound was synthesized by the reaction of 6-hydroxy-benzofuran-3-one with propargyl bromide in the presence of potassium carbonate at relatively high temperature (Hoogendoorn et al., 2011). Herein we report the crystal structure of the title compound.

In the crystal structure of the title compound, the propyn-1-yloxy group (C1–C3/O3) forms a dihedral angle of 78.44 (9)° with the fused benzofuran-3-one ring system (Fig. 1). The crystal packing is stabilized by O—H···O interactions (Table 1 and Fig. 2). The C—H···O interactions are also observed (Table 1).

For background to the development of hybrid drug candidates against tuberculosis, malaria and cancer, see: Morphy et al. (2004). For details of the synthesis of the title compound, see: Hoogendoorn et al. (2011).

Computing details top

Data collection: APEX2 (Bruker, 2011); cell refinement: SAINT (Bruker, 2008); data reduction: SAINT (Bruker, 2008); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997); software used to prepare material for publication: WinGX (Farrugia, 1999).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound with labeling and displacement ellipsoids drawn at the 50% probability level.
[Figure 2] Fig. 2. A portion of the crystal packing viewed approximately down the b axis. Dotted lines denote intermolecular O—H···O interactions.
2-(2-Hydroxypropan-2-yl)-6-(prop-2-ynyloxy)-1-benzofuran-3(2H)-one top
Crystal data top
C14H14O4Z = 2
Mr = 246.25F(000) = 260
Triclinic, P1Dx = 1.38 Mg m−3
Hall symbol: -P 1Cu Kα radiation, λ = 1.54178 Å
a = 5.4199 (2) ÅCell parameters from 4605 reflections
b = 9.0785 (3) Åθ = 4.9–66.1°
c = 12.3555 (4) ŵ = 0.84 mm−1
α = 85.758 (2)°T = 100 K
β = 80.455 (2)°Needle, colourless
γ = 81.829 (2)°0.39 × 0.11 × 0.11 mm
V = 592.65 (4) Å3
Data collection top
Bruker APEX DUO 4K CCD
diffractometer		1983 independent reflections
Incoatec Quazar Multilayer Mirror monochromator1888 reflections with I > 2σ(I)
Detector resolution: 8.4 pixels mm-1Rint = 0.025
φ and ω scansθmax = 66.3°, θmin = 4.9°
Absorption correction: multi-scan
(SADABS; Bruker, 2008)		h = −4→6
Tmin = 0.736, Tmax = 0.913k = −10→10
10266 measured reflectionsl = −14→14
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)] = 0.032Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.082H-atom parameters constrained
S = 1.03 w = 1/[σ2(Fo2) + (0.0364P)2 + 0.2704P]
where P = (Fo2 + 2Fc2)/3
1983 reflections(Δ/σ)max < 0.001
166 parametersΔρmax = 0.21 e Å−3
0 restraintsΔρmin = −0.17 e Å−3
Crystal data top
C14H14O4γ = 81.829 (2)°
Mr = 246.25V = 592.65 (4) Å3
Triclinic, P1Z = 2
a = 5.4199 (2) ÅCu Kα radiation
b = 9.0785 (3) ŵ = 0.84 mm−1
c = 12.3555 (4) ÅT = 100 K
α = 85.758 (2)°0.39 × 0.11 × 0.11 mm
β = 80.455 (2)°
Data collection top
Bruker APEX DUO 4K CCD
diffractometer		1983 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2008)		1888 reflections with I > 2σ(I)
Tmin = 0.736, Tmax = 0.913Rint = 0.025
10266 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0320 restraints
wR(F2) = 0.082H-atom parameters constrained
S = 1.03Δρmax = 0.21 e Å−3
1983 reflectionsΔρmin = −0.17 e Å−3
166 parameters
Special details top

Experimental. Analytical data: 1H NMR (CDCl3, 400 MHZ): δ 7.55 (d, 1H), 6.69 (s, 1H), 6.66 (s, 1H), 4.74 (s, 2H), 4.36 (s, 1H), 3.26 (s, 1H), 2.58 (s, 1H), 1.33 (s, 3H), 1.18 (s, 3H); 13C NMR (CDCl3, 400 MHZ): δ 199.0, 175.0, 166.2, 125.4, 115.5, 112.1, 97.4, 89.8, 72.3, 56.3, 25.9, 23.9.

The intensity data was collected on a Bruker Apex DUO 4 K CCD diffractometer using an exposure time of 5 s/frame. A total of 4558 frames were collected with a frame width of 1° covering up to θ = 66.28° with 95.2% completeness accomplished.

Geometry. All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'s 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 > 2σ(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
xyzUiso*/Ueq
C10.2006 (3)0.84616 (15)0.02726 (11)0.0261 (3)
H10.10770.8209−0.02590.031*
C20.3167 (2)0.87773 (14)0.09371 (10)0.0223 (3)
C30.4670 (2)0.91785 (15)0.17253 (10)0.0223 (3)
H3A0.63870.92990.13390.027*
H3B0.38941.01480.20260.027*
C40.2852 (2)0.80294 (13)0.34321 (10)0.0172 (3)
C50.0548 (2)0.89754 (13)0.34541 (10)0.0189 (3)
H50.03090.96880.28660.023*
C6−0.1355 (2)0.88612 (13)0.43326 (10)0.0180 (3)
H6−0.29070.95040.43620.022*
C7−0.0975 (2)0.77883 (13)0.51799 (10)0.0167 (3)
C80.1301 (2)0.68501 (13)0.51207 (10)0.0164 (3)
C90.3268 (2)0.69443 (13)0.42660 (10)0.0177 (3)
H90.48220.63060.42460.021*
C10−0.2529 (2)0.73992 (13)0.61999 (10)0.0173 (3)
C11−0.0979 (2)0.60810 (13)0.67327 (10)0.0177 (3)
H11−0.18640.51810.67630.021*
C12−0.0406 (2)0.62882 (13)0.78842 (10)0.0183 (3)
C130.1469 (2)0.49897 (14)0.82127 (11)0.0237 (3)
H13A0.30490.49620.76930.036*
H13B0.07650.40550.82030.036*
H13C0.18020.51150.89540.036*
C14−0.2814 (2)0.64049 (15)0.87195 (10)0.0233 (3)
H14A−0.24380.66370.94320.035*
H14B−0.35040.54550.87930.035*
H14C−0.40520.71980.84720.035*
O10.05931 (15)0.76695 (9)0.78783 (7)0.0193 (2)
H0.20220.76120.74860.029*
O20.14038 (15)0.58334 (9)0.59873 (7)0.0187 (2)
O30.48574 (16)0.80822 (10)0.26152 (7)0.0215 (2)
O4−0.46595 (15)0.79629 (10)0.65811 (7)0.0215 (2)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0272 (7)0.0300 (7)0.0206 (7)−0.0034 (6)−0.0019 (5)−0.0033 (5)
C20.0241 (7)0.0221 (6)0.0176 (6)−0.0009 (5)0.0036 (5)0.0003 (5)
C30.0251 (7)0.0247 (7)0.0167 (6)−0.0065 (5)−0.0002 (5)0.0016 (5)
C40.0184 (6)0.0194 (6)0.0144 (6)−0.0047 (5)−0.0010 (5)−0.0043 (5)
C50.0222 (6)0.0188 (6)0.0161 (6)−0.0023 (5)−0.0050 (5)−0.0006 (5)
C60.0173 (6)0.0185 (6)0.0187 (6)−0.0003 (5)−0.0047 (5)−0.0033 (5)
C70.0163 (6)0.0180 (6)0.0166 (6)−0.0030 (4)−0.0035 (5)−0.0038 (5)
C80.0204 (6)0.0151 (6)0.0150 (6)−0.0034 (5)−0.0049 (5)−0.0024 (4)
C90.0171 (6)0.0186 (6)0.0175 (6)−0.0002 (5)−0.0034 (5)−0.0038 (5)
C100.0166 (6)0.0197 (6)0.0174 (6)−0.0050 (5)−0.0041 (5)−0.0041 (5)
C110.0161 (6)0.0187 (6)0.0176 (6)−0.0037 (5)0.0003 (5)−0.0010 (5)
C120.0184 (6)0.0195 (6)0.0171 (6)−0.0046 (5)−0.0021 (5)0.0010 (5)
C130.0242 (7)0.0239 (7)0.0220 (7)−0.0013 (5)−0.0043 (5)0.0033 (5)
C140.0214 (7)0.0302 (7)0.0175 (6)−0.0045 (5)−0.0013 (5)0.0024 (5)
O10.0183 (5)0.0207 (5)0.0188 (4)−0.0044 (3)−0.0002 (3)−0.0024 (3)
O20.0204 (5)0.0182 (4)0.0156 (4)0.0009 (3)−0.0002 (3)0.0006 (3)
O30.0197 (5)0.0272 (5)0.0155 (4)−0.0010 (3)0.0005 (3)0.0015 (3)
O40.0154 (5)0.0279 (5)0.0203 (5)−0.0017 (3)−0.0014 (3)−0.0012 (4)
Geometric parameters (Å, º) top
C1—C21.187 (2)C9—H90.95
C1—H10.95C10—O41.2264 (15)
C2—C31.4647 (18)C10—C111.5338 (17)
C3—O31.4339 (15)C11—O21.4561 (14)
C3—H3A0.99C11—C121.5359 (17)
C3—H3B0.99C11—H111
C4—O31.3586 (14)C12—O11.4339 (14)
C4—C91.3952 (17)C12—C141.5198 (17)
C4—C51.4092 (18)C12—C131.5206 (17)
C5—C61.3767 (17)C13—H13A0.98
C5—H50.95C13—H13B0.98
C6—C71.3968 (17)C13—H13C0.98
C6—H60.95C14—H14A0.98
C7—C81.3906 (17)C14—H14B0.98
C7—C101.4454 (17)C14—H14C0.98
C8—O21.3640 (15)O1—H0.84
C8—C91.3777 (17)
C2—C1—H1180C7—C10—C11105.72 (10)
C1—C2—C3177.97 (13)O2—C11—C10105.17 (9)
O3—C3—C2112.50 (10)O2—C11—C12108.40 (9)
O3—C3—H3A109.1C10—C11—C12116.67 (10)
C2—C3—H3A109.1O2—C11—H11108.8
O3—C3—H3B109.1C10—C11—H11108.8
C2—C3—H3B109.1C12—C11—H11108.8
H3A—C3—H3B107.8O1—C12—C14106.41 (10)
O3—C4—C9113.90 (10)O1—C12—C13110.61 (10)
O3—C4—C5123.96 (11)C14—C12—C13110.22 (10)
C9—C4—C5122.14 (11)O1—C12—C11109.16 (9)
C6—C5—C4119.68 (11)C14—C12—C11110.66 (10)
C6—C5—H5120.2C13—C12—C11109.74 (10)
C4—C5—H5120.2C12—C13—H13A109.5
C5—C6—C7119.14 (11)C12—C13—H13B109.5
C5—C6—H6120.4H13A—C13—H13B109.5
C7—C6—H6120.4C12—C13—H13C109.5
C8—C7—C6119.71 (11)H13A—C13—H13C109.5
C8—C7—C10107.37 (10)H13B—C13—H13C109.5
C6—C7—C10132.92 (11)C12—C14—H14A109.5
O2—C8—C9123.28 (11)C12—C14—H14B109.5
O2—C8—C7113.74 (10)H14A—C14—H14B109.5
C9—C8—C7122.98 (11)C12—C14—H14C109.5
C8—C9—C4116.33 (11)H14A—C14—H14C109.5
C8—C9—H9121.8H14B—C14—H14C109.5
C4—C9—H9121.8C12—O1—H109.5
O4—C10—C7128.78 (11)C8—O2—C11107.95 (9)
O4—C10—C11125.50 (11)C4—O3—C3118.88 (9)
O3—C4—C5—C6−178.39 (10)O4—C10—C11—O2−179.31 (10)
C9—C4—C5—C61.43 (18)C7—C10—C11—O21.55 (12)
C4—C5—C6—C7−1.02 (17)O4—C10—C11—C12−59.16 (16)
C5—C6—C7—C8−0.40 (17)C7—C10—C11—C12121.70 (11)
C5—C6—C7—C10178.94 (12)O2—C11—C12—O168.57 (11)
C6—C7—C8—O2−178.57 (10)C10—C11—C12—O1−49.84 (13)
C10—C7—C8—O21.93 (14)O2—C11—C12—C14−174.64 (9)
C6—C7—C8—C91.55 (18)C10—C11—C12—C1466.94 (13)
C10—C7—C8—C9−177.94 (11)O2—C11—C12—C13−52.79 (12)
O2—C8—C9—C4178.99 (10)C10—C11—C12—C13−171.21 (10)
C7—C8—C9—C4−1.15 (18)C9—C8—O2—C11178.98 (10)
O3—C4—C9—C8179.49 (10)C7—C8—O2—C11−0.89 (13)
C5—C4—C9—C8−0.34 (17)C10—C11—O2—C8−0.46 (12)
C8—C7—C10—O4178.84 (12)C12—C11—O2—C8−125.94 (10)
C6—C7—C10—O4−0.6 (2)C9—C4—O3—C3−178.56 (10)
C8—C7—C10—C11−2.06 (12)C5—C4—O3—C31.28 (17)
C6—C7—C10—C11178.53 (12)C2—C3—O3—C4−76.90 (13)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1—H···O4i0.842.012.8328 (12)167
C1—H1···O1ii0.952.453.3283 (16)154
C5—H5···O1iii0.952.523.3809 (15)152
Symmetry codes: (i) x+1, y, z; (ii) x, y, z−1; (iii) −x, −y+2, −z+1.

Experimental details

Crystal data
Chemical formulaC14H14O4
Mr246.25
Crystal system, space groupTriclinic, P1
Temperature (K)100
a, b, c (Å)5.4199 (2), 9.0785 (3), 12.3555 (4)
α, β, γ (°)85.758 (2), 80.455 (2), 81.829 (2)
V (Å3)592.65 (4)
Z2
Radiation typeCu Kα
µ (mm−1)0.84
Crystal size (mm)0.39 × 0.11 × 0.11
Data collection
DiffractometerBruker APEX DUO 4K CCD
Absorption correctionMulti-scan
(SADABS; Bruker, 2008)
Tmin, Tmax0.736, 0.913
No. of measured, independent and
observed [I > 2σ(I)] reflections		10266, 1983, 1888
Rint0.025
(sin θ/λ)max (Å−1)0.594
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.032, 0.082, 1.03
No. of reflections1983
No. of parameters166
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å−3)0.21, −0.17

Computer programs: APEX2 (Bruker, 2011), SAINT (Bruker, 2008), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 1997), WinGX (Farrugia, 1999).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1—H···O4i0.842.012.8328 (12)167.3
C1—H1···O1ii0.952.453.3283 (16)153.5
C5—H5···O1iii0.952.523.3809 (15)151.6
Symmetry codes: (i) x+1, y, z; (ii) x, y, z−1; (iii) −x, −y+2, −z+1.
 

Acknowledgements

Research funds of the University of Johannesburg is gratefully acknowledged.

References

First citationBruker (2008). SADABS and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.  Google Scholar
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Journal logoCRYSTALLOGRAPHIC
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ISSN: 2056-9890
Volume 68| Part 12| December 2012| Page o3379
doi:10.1107/S1600536812045606
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