research communications\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 73| Part 8| August 2017| Pages 1227-1231
https://doi.org/10.1107/S2056989017010556

Steric repulsion and supra­molecular assemblies via a two-dimensional plate by C—H⋯O hydrogen bonds in two closely related 2-(benzo­furan-2-yl)-2-oxo­ethyl benzoates

CROSSMARK_Color_square_no_text.svg
Li Yee Then,a C. S. Chidan Kumar,b* Huey Chong Kwong,c Yip-Foo Win,d Siau Hui Mah,e Ching Kheng Quah,a S. Naveenf and Ismail Waradg*

aX-ray Crystallography Unit, School of Physics, Universiti Sains Malaysia, 11800 USM, Penang, Malaysia, bDepartment of Engineering Chemistry, Vidya Vikas Institute of Engineering & Technology, Visvesvaraya Technological University, Alanahally, Mysuru 570 028, Karnataka, India, cSchool of Chemical Sciences, Universiti Sains Malaysia, Penang 11800 USM, Malaysia, dDepartment of Chemical Science, Faculty of Science, Universiti Tunku Abdul Rahman, Perak Campus, Jalan Universiti, Bandar Barat, Perak, Malaysia, eSchool of Biosciences, Taylor's University, Lakeside Campus, 47500 Subang Jaya, Selangor, Malaysia, fInstitution of Excellence, University of Mysore, Manasagangotri, Mysuru 570 006, India, and gDepartment of Chemistry, Science College, An-Najah National University, PO Box 7, Nablus, West Bank, Palestinian Territories
*Correspondence e-mail: chidankumar@gmail.com, khalil.i@najah.edu

Edited by P. McArdle, National University of Ireland, Ireland (Received 14 July 2017; accepted 17 July 2017; online 21 July 2017)

2-(Benzo­furan-2-yl)-2-oxoethyl 2-chloro­benzoate, C17H11ClO4 (I), and 2-(benzo­furan-2-yl)-2-oxoethyl 2-meth­oxy­benzoate, C18H14O5 (II), were synthesized under mild conditions. Their chemical and mol­ecular structures were analyzed by spectroscopic and single-crystal X-ray diffraction studies, respectively. These compounds possess different ortho-substituted functional groups on their phenyl rings, thus experiencing extra steric repulsion force within their mol­ecules as the substituent changes from 2-chloro (I) to 2-meth­oxy (II). The crystal packing of compound (I) depends on weak inter­molecular hydrogen bonds and π–π inter­actions. Mol­ecules are related by inversion into centrosymmetric dimers via C—H⋯O hydrogen bonds, and further strengthened by π–π inter­actions between furan rings. Conversely, mol­ecules in compound (II) are linked into alternating dimeric chains propagating along the [101] direction, which develop into a two-dimensional plate through extensive inter­molecular hydrogen bonds. These plates are further stabilized by π–π and C—H⋯π inter­actions.

CCDC references: 1449585; 1037757

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1. Chemical context

Benzo­furans are an important class of heterocyclic compounds with fused benzene and furan rings. The benzo­furan nucleus has been widely used as the building block for various biologically active compounds due to its broad range of pharmacological properties (Swamy et al., 2015[Swamy, P. M. G., Prasad, Y. R., Ashvini, H. M., Giles, D., Shashidhar, B. V. & Agasimundin, Y. S. (2015). Med. Chem. Res. 24, 3437-3452.]; Zhou et al., 2010[Zhou, X., Li, M., Wang, X.-B., Wang, T. & Kong, L.-Y. (2010). Molecules, 15, 8593-8601.]; Rangaswamy et al., 2012[Rangaswamy, J., Vijay Kumar, H., Harini, S. T. & Naik, N. (2012). Bioorg. Med. Chem. Lett. 22, 4773-4777.]). Benzo­furan derivatives, especially with substituents at their C-2 position, are commonly found in natural products and synthetic compounds. Several reviews describing the biological potential of these scaffolds acting as anti­oxidant (Chand et al., 2017[Chand, K., Rajeshwari, Hiremathad, A., Singh, M., Santos, M. A. & Keri, R. S. (2017). Pharmacol. Rep. 69, 281-295.]), anti­microbial (Hiremathad et al., 2015[Hiremathad, A., Patil, M. R. K. R. C., Chand, K., Santos, M. A. & Keri, R. S. (2015). RSC Adv. 5, 96809-96828.]), anti­cancer and anti­viral (Khanam & Shamsuzzaman, 2015[Khanam, H. & Shamsuzzaman (2015). Eur. J. Med. Chem. 97, 483-504.]) agents have been published. Encouraged by previous studies, we are herein reporting the synthesis, spectroscopic studies and structure determination of 2-(benzo­furan-2-yl)-2-oxoethyl 2-chloro­benzoate (I)[link] and 2-(benzo­furan-2-yl)-2-oxoethyl 2-meth­oxy­benzoate (II)[link].

[Scheme 1]

2. Structural commentary

The mol­ecular structure of the title compounds (Fig. 1[link]) contain two ring systems, which are the benzo­furan and the ortho-substituted [chloro- for (I)[link] and meth­oxy- for (II)] phenyl rings, inter­connected by a C—C(=O)—O—C(=O) connecting bridge. The unique mol­ecular conformations of compounds (I)[link] and (II)[link] can be characterized by three torsion angles, i.e. τ1 (O1—C8—C9—O3), τ2 (C9—C10—O2—C11) and τ3 (O4—C11—C12—C13) respectively (Fig. 2[link]). The torsion angle τ1 for both structures is approximately 0°, signifying the coplanarity between their benzo­furan ring and the adjacent carbonyl group at the connecting bridge. As for the torsion angle between the two carbonyl groups, τ2, compound (I)[link] exhibits a syn-clinal conformation [C9—C10—O2—C11 = −76.19 (17)°] whereas compound (II)[link] adopts an anti-periplanar conformation [C9—C10—O2—C11 = −173.51 (9)°]. Likewise, owing to the ortho-substitution of the functional group at their phenyl rings, both studied compounds experience steric repulsion between their substituent and adjacent carbonyl groups, which can influence torsion angle τ3. Greater steric repulsion force is observed between carbonyl group and meth­oxy groups [O4—C11—C12—C13 = 123.09 (14)° for compound (II)] than with the chlorine atom [O4—C11—C12—C13 = 22.0 (3)° for compound (I)] (Then et al., 2017[Then, L. Y., Chidan Kumar, C. S., Kwong, H. C., Win, Y.-F., Mah, S. H., Quah, C. K., Naveen, S. & Warad, I. (2017). Acta Cryst. E73, 1087-1091.]).

[Figure 1]
Figure 1
The structures of (I)[link] and (II)[link], showing 50% probability displacement ellipsoids and the atomic labelling scheme.
[Figure 2]
Figure 2
General chemical diagram showing the torsion angles τ1, τ2 and τ3.

3. Supra­molecular features

The crystal packing of compound (I)[link] features weak inter­molecular hydrogen bonds (Table 1[link]) and π–π inter­actions. Two inversion-related mol­ecules are joined to form a centrosymmetric dimer by a pair of weak inter­molecular C10—H10B⋯O4 hydrogen bonds, generating an R22(10) graph-set motif (Fig. 3[link]). These dimers are further consolidated by π–π inter­actions, involving two face-to-face related furan rings, distanced by 3.6623 (11) Å, propagating along the [001] direction (Fig. 4[link]) with symmetry code −x + 1, −y + 1, −z + 1.

Table 1
Hydrogen-bond geometry (Å, °) for (I)[link]

D—H⋯A D—H H⋯A D⋯A D—H⋯A
C10—H10B⋯O4i 0.97 2.53 3.495 (2) 176
Symmetry code: (i) -x+1, -y+1, -z+2.
[Figure 3]
Figure 3
The dimeric structure of compound (I)[link] formed by two adjacent inversion-related mol­ecules.
[Figure 4]
Figure 4
The crystal packing of compound (I)[link], showing hydrogen bonds (cyan dotted lines) and π–π inter­actions (red dotted lines).

Contrasting with compound (I)[link], compound (II)[link] is assembled by extensive inter­molecular inter­actions (Table 2[link]). Mol­ecules are linked into inversion dimer–dimer chains through weak C2—H2A⋯O3, C10—H10B⋯O4 and C7—H7A⋯O4 hydrogen bonds, propagating along the [101] direction (Fig. 5[link]). The centrosymmetric dimer formed by the C2—H2A⋯O3 hydrogen-bond pairs generates an R22(14) ring motif. On the other hand, atom O4 serves as a bifurcated acceptor in the R12(7) motif and yet, participates in a second R22(10) ring motif. These dimer–dimer chains are further expanded by C10—H10A⋯O3 and C17—H17A⋯O1 hydrogen bonds through inversion to build a two-dimensional plate parallel to the ac-plane (Fig. 6[link]). Within these plates, two kinds of π–π inter­actions further stabilize the crystal packing: these inter­actions are between furan rings [centroid–centroid separation: 3.4402 (7) Å; symmetry code: −x + 1, −y + 1, −z + 1] and between a furan ring and a benzene ring [centroid–centroid separation: 3.6088 (7) Å; symmetry code: −x + 1, −y + 1, −z + 1]. In addition, neighboring plates are inter­connected via C—H⋯π inter­actions involving the substituted meth­oxy group and an adjacent phenyl ring (Fig. 7[link]).

Table 2
Hydrogen-bond geometry (Å, °) for (II)[link]

Cg3 is the centroid of the C12–C17 ring.
D—H⋯A D—H H⋯A D⋯A D—H⋯A
C2—H2A⋯O3i 0.95 2.45 3.2677 (15) 145
C7—H7A⋯O4ii 0.95 2.31 3.2352 (16) 163
C10—H10A⋯O3iii 0.99 2.55 3.3746 (14) 141
C10—H10B⋯O4ii 0.99 2.44 3.2028 (17) 134
C17—H17A⋯O1iii 0.95 2.55 3.2730 (15) 134
C18—H18C⋯Cg3iv 0.98 2.81 3.6181 (16) 141
Symmetry codes: (i) -x, -y+1, -z+1; (ii) -x+1, -y+1, -z+2; (iii) -x, -y+1, -z+2; (iv) -x, -y+2, -z+2.
[Figure 5]
Figure 5
Inter­molecular hydrogen bonds joining mol­ecules into an endless chain in compound (II)[link].
[Figure 6]
Figure 6
Inter­molecular inter­actions in compound (II)[link], showing the two-dimensional plate parallel to the ac plane.
[Figure 7]
Figure 7
Extensive inter­molecular inter­actions in compound (II)[link], showing hydrogen bonds (cyan dotted lines), C—H⋯π inter­actions (blue dotted lines) and π–π inter­actions (red dotted lines).

4. Database survey

A search of the Cambridge Structural Database (Groom et al., 2016[Groom, C. R., Bruno, I. J., Lightfoot, M. P. & Ward, S. C. (2016). Acta Cryst. B72, 171-179.]) by using 2-(1-benzo­furan-2-yl)-2-oxoethyl benzoate as reference skeleton has revealed five benzo­furan structures (Kumar et al., 2015[Kumar, C., Then, L., Chia, T., Chandraju, S., Win, Y.-F., Sulaiman, S., Hashim, N., Ooi, K., Quah, C. & Fun, H.-K. (2015). Molecules, 20, 16566-16581.]) related to the title compounds, i.e. ITAXUY, ITAYAF, ITAYEJ, ITAYIN and ITAYOT. The mol­ecular structures of these compounds differ only at their substituted phenyl rings, especially compound (I)[link] with ITAYAF and compound (II)[link] with ITAYIN, which have the same substituents at altered positions. By looking at their torsion angles at the C—C(=O)—O—C(=O) carbonyl connecting bridge, compound (I)[link] was found to exhibit a syn-clinal conformation similar to ITAXUY, ITAYEJ and ITAYIN (τ2 ranges from 75 to 80°) whereas compound (II)[link] shows an anti-periplanar conformation as do ITAYAF and ITAYOT (ranging from 163 to 180°).

5. Synthesis and crystallization

The title compounds were synthesized by dissolving a mixture of 1-(benzo­furan-2-yl)-2-bromo­ethan-1-one (1 mmol) with 2-chloro­benzoic acid (1 mmol) for compound (I)[link] and 2-meth­oxy­benzoic acid (1 mmol) for compound (II)[link] in N,N-di­methyl­formamide (8 ml). The solution was stirred for about two h at room temperature in the presence of a catalytic amount of anhydrous potassium carbonate and the progress was monitored by thin-layer chromatography (TLC). Once the reaction was complete, the resultant mixture was poured into a beaker of ice cooled water which gave a precipitate. The precipitate obtained was then filtered, washed with distilled water and dried. Finally, pure crystals suitable for X-ray analysis were obtained by slow evaporation using a suitable solvent.

2-(Benzo­furan-2-yl)-2-oxoethyl 2-chloro­benzoate (I)[link]:

Solvent used to grow crystals: acetone; yield: 79%; m.p. 366–368 K. 1H NMR (500 MHz, CDCl3) in ppm: δ 8.086–8.070 (d, 1H, J = 7.9 Hz, 17CH), 7.773–7.757 (d, 1H, J = 7.9 Hz, 14CH), 7.669 (s, 1H, 7CH), 7.632–7.615 (d, 1H, J = 8.4 Hz, 2CH), 7.564–7.530 (t, 1H, J = 8.4 Hz, 3CH), 7.526–7.510 (d, 1H, J = 8.4 Hz, 5CH), 7.507–7.474 (t, 1H, J = 8.4 Hz, 4CH), 7.407–7.355 (m, 2H, 15CH, 16CH), 5.595 (s, 2H, 10CH2). 13C NMR (125 MHz, CDCl3) in ppm: 183.38 (C9), 164.79 (C11), 155.69 (C1), 150.41 (C8), 134.23 (C12), 133.09 (C15), 132.03 (C16), 131.20 (C3), 129.01 (C6), 128.81 (C14), 126.71 (C5), 126.70 (C4), 124.25 (C13), 123.55 (C17), 113.57 (C7), 112.51 (C2), 66.43 (C10). FT–IR (ATR (solid) cm−1): 3074 (Ar C—H, ν), 2949 (C—H, ν), 1736, 1686 (C=O, ν), 1612 (C=C, ν), 1554, 1472 (Ar C=C, ν), 1255, 1115 (C—O, ν), 1066 (C—Cl, ν).

2-(Benzo­furan-2-yl)-2-oxoethyl 2-meth­oxy­benzoate (II)[link]:

Solvent used to grow crystals: acetone; yield: 83%; m.p. 378–380 K. 1H NMR (500 MHz, CDCl3) in ppm: δ 8.047–8.032 (d, 1H, J = 8.0 Hz, 17CH), 7.768–7.752 (d, 1H, J = 8.0 Hz, 14CH), 7.681 (s, 1H, 7CH), 7.636–7.619 (d, 1H, J = 8.5 Hz, 2CH), 7.569–7.523 (m, 2H, 5CH, 16CH), 7.381–7.349 (t, 1H, J = 8.0 Hz, 15CH), 7.071–7.033 (m, 2H,3CH, 4CH), 5.535 (s, 2H, 10CH2), 3.955 (s, 3H, 18CH3). 13C NMR (125 MHz, CDCl3) in ppm: 183.98 (C9), 165.18 (C11), 159.68 (C13), 155.66 (C1), 150.55 (C8), 134.22 (C15), 132.33 (C17), 128.68 (C3), 126.77 (C6), 124.15 (C5), 123.48 (C4), 120.26 (C16), 118.80 (C12), 113.57 (C7), 112.53 (C2), 112.10 (C14), 66.09 (C10), 56.05 (C18). FT–IR (ATR (solid) cm−1): 3081 (Ar C—H, ν), 2921 (C—H, ν), 1762, 1686 (C=O, ν), 1601 (C=C, ν), 1554, 1465 (Ar C=C, ν), 1255, 1101 (C—O, ν).

6. Refinement

Crystal data, data collection and structure refinement details are tabulated in Table 3[link]. All C-bound H atoms were positioned geometrically (C—H = 0.93–0.97 Å). Refinement was done using a riding model with Uiso(H) = 1.5Ueq(C-meth­yl) and 1.2Ueq(C) for other H atoms.

Table 3
Experimental details

  (I) (II)
Crystal data
Chemical formula C17H11ClO4 C18H14O5
Mr 314.71 310.29
Crystal system, space group Triclinic, P[\overline{1}] Triclinic, P[\overline{1}]
Temperature (K) 294 100
a, b, c (Å) 5.5333 (8), 11.3212 (17), 11.5186 (18) 7.4094 (3), 9.7566 (4), 10.5832 (5)
α, β, γ (°) 92.283 (3), 91.536 (3), 99.638 (3) 83.430 (1), 71.808 (1), 87.265 (1)
V (Å3) 710.41 (19) 721.99 (5)
Z 2 2
Radiation type Mo Kα Mo Kα
μ (mm−1) 0.28 0.11
Crystal size (mm) 0.54 × 0.25 × 0.21 0.51 × 0.35 × 0.11
 
Data collection
Diffractometer Bruker APEXII DUO CCD area-detector Bruker APEXII DUO CCD area-detector
Absorption correction Multi-scan (SADABS; Bruker, 2009[Bruker (2009). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Multi-scan (SADABS; Krause et al., 2015[Krause, L., Herbst-Irmer, R., Sheldrick, G. M. & Stalke, D. (2015). J. Appl. Cryst. 48, 3-10.])
Tmin, Tmax 0.799, 0.944 0.766, 0.950
No. of measured, independent and observed [I > 2σ(I)] reflections 12081, 3798, 2860 27838, 4286, 3615
Rint 0.026 0.046
(sin θ/λ)max (Å−1) 0.688 0.708
 
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.045, 0.145, 1.03 0.045, 0.124, 1.04
No. of reflections 3798 4286
No. of parameters 199 209
H-atom treatment H-atom parameters constrained H-atom parameters constrained
Δρmax, Δρmin (e Å−3) 0.31, −0.27 0.52, −0.33
Computer programs: APEX2 and SAINT (Bruker, 2009[Bruker (2009). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]), XS (Sheldrick, 2013[Sheldrick, G. M. (2013). XS. Georg-August-Universität Göttingen, Germany.]), SHELXL2013 (Sheldrick, 2015[Sheldrick, G. M. (2015). Acta Cryst. C71, 3-8.]), Mercury (Macrae et al., 2006[Macrae, C. F., Edgington, P. R., McCabe, P., Pidcock, E., Shields, G. P., Taylor, R., Towler, M. & van de Streek, J. (2006). J. Appl. Cryst. 39, 453-457.]) and PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]).

Supporting information

CCDC references: 1449585; 1037757

Crystal structure: contains datablocks global, I, II. DOI: https://doi.org/10.1107/S2056989017010556/qm2117sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2056989017010556/qm2117Isup2.hkl

Structure factors: contains datablock II. DOI: https://doi.org/10.1107/S2056989017010556/qm2117IIsup3.hkl

checkCIF report


Computing details top

For both structures, data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009). Program(s) used to solve structure: XS (Sheldrick, 2013) for (I); XS (Sheldrick, 2013) for (II). Program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015) for (I); SHELXL2013 (Sheldrick, 2015) for (II). For both structures, molecular graphics: SHELXL2013 (Sheldrick, 2015) and Mercury (Macrae et al., 2006); software used to prepare material for publication: SHELXL2013 (Sheldrick, 2015) and PLATON (Spek, 2009).

2-(Benzofuran-2-yl)-2-oxoethyl 2-chlorobenzoate (I) top
Crystal data top
C17H11ClO4Z = 2
Mr = 314.71F(000) = 324
Triclinic, P1Dx = 1.471 Mg m−3
a = 5.5333 (8) ÅMo Kα radiation, λ = 0.71073 Å
b = 11.3212 (17) ÅCell parameters from 4675 reflections
c = 11.5186 (18) Åθ = 2.5–29.0°
α = 92.283 (3)°µ = 0.28 mm−1
β = 91.536 (3)°T = 294 K
γ = 99.638 (3)°Block, yellow
V = 710.41 (19) Å30.54 × 0.25 × 0.21 mm
Data collection top
Bruker APEXII DUO CCD area-detector
diffractometer		3798 independent reflections
Radiation source: fine-focus sealed tube2860 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.026
φ and ω scansθmax = 29.3°, θmin = 1.8°
Absorption correction: multi-scan
(SADABS; Bruker, 2009)		h = −7→7
Tmin = 0.799, Tmax = 0.944k = −15→15
12081 measured reflectionsl = −15→15
Refinement top
Refinement on F20 restraints
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.045H-atom parameters constrained
wR(F2) = 0.145 w = 1/[σ2(Fo2) + (0.0759P)2 + 0.1547P]
where P = (Fo2 + 2Fc2)/3
S = 1.03(Δ/σ)max = 0.001
3798 reflectionsΔρmax = 0.31 e Å−3
199 parametersΔρmin = −0.27 e Å−3
Special details top

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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
Cl11.19628 (9)0.69545 (5)1.14636 (5)0.06498 (18)
O10.7395 (2)0.47462 (10)0.60559 (10)0.0487 (3)
O20.5749 (2)0.74445 (10)0.91565 (10)0.0472 (3)
O30.8481 (3)0.67643 (12)0.74537 (13)0.0669 (4)
O40.7470 (3)0.61109 (11)1.01203 (13)0.0651 (4)
C10.6380 (3)0.36403 (15)0.55782 (13)0.0451 (4)
C20.7437 (4)0.30006 (18)0.47427 (16)0.0595 (5)
H2A0.89250.33030.44210.071*
C30.6141 (5)0.18868 (19)0.44183 (18)0.0683 (6)
H3A0.67740.14190.38590.082*
C40.3920 (5)0.14375 (18)0.48973 (18)0.0653 (5)
H4A0.31190.06730.46620.078*
C50.2876 (4)0.20964 (17)0.57136 (17)0.0579 (4)
H5A0.13730.17960.60230.069*
C60.4152 (3)0.32335 (14)0.60635 (13)0.0443 (4)
C70.3768 (3)0.41575 (15)0.68858 (14)0.0450 (4)
H7A0.24180.41590.73490.054*
C80.5753 (3)0.50274 (14)0.68559 (13)0.0429 (3)
C90.6496 (3)0.61413 (14)0.75465 (14)0.0459 (4)
C100.4630 (3)0.64691 (15)0.83864 (15)0.0489 (4)
H10A0.32620.66980.79570.059*
H10B0.40080.57810.88320.059*
C110.7212 (3)0.71241 (14)1.00006 (14)0.0438 (3)
C120.8368 (3)0.81814 (14)1.07463 (13)0.0419 (3)
C131.0492 (3)0.81829 (16)1.14281 (14)0.0465 (4)
C141.1527 (4)0.9200 (2)1.20965 (16)0.0601 (5)
H14A1.29500.91961.25440.072*
C151.0459 (4)1.02112 (19)1.20989 (17)0.0638 (5)
H15A1.11651.08921.25430.077*
C160.8358 (4)1.02186 (17)1.14495 (17)0.0619 (5)
H16A0.76211.08991.14610.074*
C170.7331 (4)0.92144 (15)1.07765 (16)0.0515 (4)
H17A0.59100.92321.03330.062*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cl10.0480 (3)0.0749 (3)0.0767 (3)0.0207 (2)−0.0007 (2)0.0182 (2)
O10.0479 (6)0.0484 (6)0.0486 (6)0.0049 (5)0.0077 (5)−0.0005 (5)
O20.0540 (7)0.0423 (6)0.0454 (6)0.0109 (5)−0.0056 (5)−0.0029 (4)
O30.0618 (8)0.0570 (8)0.0754 (9)−0.0079 (7)0.0171 (7)−0.0119 (6)
O40.0736 (9)0.0398 (6)0.0813 (9)0.0112 (6)−0.0169 (7)0.0035 (6)
C10.0504 (9)0.0461 (8)0.0401 (7)0.0120 (7)−0.0007 (6)0.0030 (6)
C20.0661 (12)0.0651 (12)0.0506 (9)0.0201 (10)0.0100 (8)−0.0007 (8)
C30.0932 (16)0.0647 (12)0.0519 (10)0.0311 (12)0.0006 (10)−0.0109 (9)
C40.0868 (15)0.0502 (10)0.0568 (10)0.0101 (10)−0.0124 (10)−0.0096 (8)
C50.0612 (11)0.0530 (10)0.0554 (10)0.0001 (8)−0.0054 (8)−0.0018 (8)
C60.0471 (9)0.0457 (8)0.0402 (7)0.0090 (7)−0.0036 (6)0.0019 (6)
C70.0427 (8)0.0485 (9)0.0435 (8)0.0071 (7)0.0015 (6)0.0000 (6)
C80.0449 (8)0.0439 (8)0.0405 (7)0.0096 (6)0.0019 (6)0.0022 (6)
C90.0478 (9)0.0426 (8)0.0466 (8)0.0053 (7)0.0010 (7)0.0020 (6)
C100.0497 (9)0.0476 (9)0.0480 (8)0.0072 (7)−0.0030 (7)−0.0073 (7)
C110.0437 (8)0.0413 (8)0.0473 (8)0.0093 (6)0.0020 (6)0.0037 (6)
C120.0425 (8)0.0422 (8)0.0407 (7)0.0060 (6)0.0035 (6)0.0039 (6)
C130.0404 (8)0.0553 (9)0.0438 (8)0.0056 (7)0.0057 (6)0.0091 (7)
C140.0514 (10)0.0745 (13)0.0478 (9)−0.0070 (9)−0.0029 (8)0.0010 (8)
C150.0749 (13)0.0563 (11)0.0528 (10)−0.0084 (10)0.0052 (9)−0.0070 (8)
C160.0786 (14)0.0459 (10)0.0604 (11)0.0097 (9)0.0077 (10)−0.0062 (8)
C170.0557 (10)0.0446 (9)0.0548 (9)0.0116 (7)−0.0016 (8)−0.0009 (7)
Geometric parameters (Å, º) top
Cl1—C131.7261 (18)C7—C81.349 (2)
O1—C11.371 (2)C7—H7A0.9300
O1—C81.3764 (19)C8—C91.456 (2)
O2—C111.3480 (19)C9—C101.514 (2)
O2—C101.4328 (19)C10—H10A0.9700
O3—C91.212 (2)C10—H10B0.9700
O4—C111.1922 (19)C11—C121.487 (2)
C1—C21.382 (2)C12—C171.386 (2)
C1—C61.382 (2)C12—C131.396 (2)
C2—C31.374 (3)C13—C141.390 (3)
C2—H2A0.9300C14—C151.373 (3)
C3—C41.386 (4)C14—H14A0.9300
C3—H3A0.9300C15—C161.367 (3)
C4—C51.375 (3)C15—H15A0.9300
C4—H4A0.9300C16—C171.381 (3)
C5—C61.399 (2)C16—H16A0.9300
C5—H5A0.9300C17—H17A0.9300
C6—C71.429 (2)
C1—O1—C8105.45 (12)C8—C9—C10115.69 (15)
C11—O2—C10114.00 (12)O2—C10—C9109.79 (14)
O1—C1—C2125.23 (17)O2—C10—H10A109.7
O1—C1—C6110.63 (14)C9—C10—H10A109.7
C2—C1—C6124.13 (17)O2—C10—H10B109.7
C3—C2—C1115.5 (2)C9—C10—H10B109.7
C3—C2—H2A122.2H10A—C10—H10B108.2
C1—C2—H2A122.2O4—C11—O2122.75 (16)
C2—C3—C4122.16 (19)O4—C11—C12126.00 (16)
C2—C3—H3A118.9O2—C11—C12111.24 (13)
C4—C3—H3A118.9C17—C12—C13117.76 (16)
C5—C4—C3121.47 (19)C17—C12—C11119.77 (15)
C5—C4—H4A119.3C13—C12—C11122.48 (14)
C3—C4—H4A119.3C14—C13—C12120.36 (17)
C4—C5—C6117.8 (2)C14—C13—Cl1117.41 (14)
C4—C5—H5A121.1C12—C13—Cl1122.23 (14)
C6—C5—H5A121.1C15—C14—C13120.29 (18)
C1—C6—C5118.95 (16)C15—C14—H14A119.9
C1—C6—C7105.80 (15)C13—C14—H14A119.9
C5—C6—C7135.22 (17)C16—C15—C14120.08 (18)
C8—C7—C6106.35 (15)C16—C15—H15A120.0
C8—C7—H7A126.8C14—C15—H15A120.0
C6—C7—H7A126.8C15—C16—C17119.91 (19)
C7—C8—O1111.77 (14)C15—C16—H16A120.0
C7—C8—C9131.98 (15)C17—C16—H16A120.0
O1—C8—C9116.14 (14)C16—C17—C12121.59 (18)
O3—C9—C8122.07 (16)C16—C17—H17A119.2
O3—C9—C10122.24 (15)C12—C17—H17A119.2
C8—O1—C1—C2−178.83 (16)O1—C8—C9—C10177.42 (13)
C8—O1—C1—C60.04 (16)C11—O2—C10—C9−76.19 (17)
O1—C1—C2—C3177.55 (16)O3—C9—C10—O2−10.9 (2)
C6—C1—C2—C3−1.2 (3)C8—C9—C10—O2169.07 (13)
C1—C2—C3—C40.1 (3)C10—O2—C11—O4−2.9 (2)
C2—C3—C4—C51.1 (3)C10—O2—C11—C12178.34 (13)
C3—C4—C5—C6−1.1 (3)O4—C11—C12—C17−158.19 (18)
O1—C1—C6—C5−177.75 (14)O2—C11—C12—C1720.6 (2)
C2—C1—C6—C51.1 (2)O4—C11—C12—C1322.0 (3)
O1—C1—C6—C70.55 (17)O2—C11—C12—C13−159.28 (14)
C2—C1—C6—C7179.44 (16)C17—C12—C13—C14−0.9 (2)
C4—C5—C6—C10.0 (2)C11—C12—C13—C14178.94 (15)
C4—C5—C6—C7−177.63 (18)C17—C12—C13—Cl1−179.83 (13)
C1—C6—C7—C8−0.93 (17)C11—C12—C13—Cl10.0 (2)
C5—C6—C7—C8176.95 (18)C12—C13—C14—C150.5 (3)
C6—C7—C8—O11.01 (17)Cl1—C13—C14—C15179.46 (15)
C6—C7—C8—C9−175.02 (16)C13—C14—C15—C160.5 (3)
C1—O1—C8—C7−0.67 (17)C14—C15—C16—C17−1.0 (3)
C1—O1—C8—C9176.04 (13)C15—C16—C17—C120.6 (3)
C7—C8—C9—O3173.32 (18)C13—C12—C17—C160.4 (3)
O1—C8—C9—O3−2.6 (2)C11—C12—C17—C16−179.46 (17)
C7—C8—C9—C10−6.7 (3)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C10—H10B···O4i0.972.533.495 (2)176
C17—H17A···O20.932.382.700 (2)100
Symmetry code: (i) −x+1, −y+1, −z+2.
2-(Benzofuran-2-yl)-2-oxoethyl 2-methoxybenzoate (II) top
Crystal data top
C18H14O5Z = 2
Mr = 310.29F(000) = 324
Triclinic, P1Dx = 1.427 Mg m−3
a = 7.4094 (3) ÅMo Kα radiation, λ = 0.71073 Å
b = 9.7566 (4) ÅCell parameters from 8829 reflections
c = 10.5832 (5) Åθ = 2.8–30.2°
α = 83.430 (1)°µ = 0.11 mm−1
β = 71.808 (1)°T = 100 K
γ = 87.265 (1)°Block, colourless
V = 721.99 (5) Å30.51 × 0.35 × 0.11 mm
Data collection top
Bruker APEXII DUO CCD area-detector
diffractometer		4286 independent reflections
Radiation source: fine-focus sealed tube3615 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.046
φ and ω scansθmax = 30.2°, θmin = 2.0°
Absorption correction: multi-scan
(SADABS; Krause et al., 2015)		h = −10→10
Tmin = 0.766, Tmax = 0.950k = −13→13
27838 measured reflectionsl = −14→14
Refinement top
Refinement on F20 restraints
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.045H-atom parameters constrained
wR(F2) = 0.124 w = 1/[σ2(Fo2) + (0.064P)2 + 0.3014P]
where P = (Fo2 + 2Fc2)/3
S = 1.04(Δ/σ)max = 0.001
4286 reflectionsΔρmax = 0.52 e Å−3
209 parametersΔρmin = −0.33 e Å−3
Special details top

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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
O10.17733 (11)0.47109 (8)0.59014 (8)0.01564 (17)
O20.17204 (12)0.66894 (8)0.98339 (8)0.01707 (18)
O30.01605 (12)0.62351 (9)0.79953 (8)0.01888 (18)
O40.36010 (15)0.60784 (11)1.11020 (10)0.0314 (2)
O50.30167 (13)0.95091 (9)0.94102 (8)0.01990 (19)
C10.28755 (15)0.38063 (11)0.50676 (11)0.0145 (2)
C20.26141 (17)0.34956 (13)0.38921 (11)0.0190 (2)
H2A0.16200.39010.35800.023*
C30.38996 (18)0.25537 (13)0.32014 (12)0.0215 (2)
H3A0.37820.23020.23900.026*
C40.53699 (18)0.19608 (13)0.36640 (12)0.0224 (2)
H4A0.62290.13260.31570.027*
C50.55911 (17)0.22858 (13)0.48483 (12)0.0198 (2)
H5A0.65830.18780.51620.024*
C60.43110 (15)0.32313 (11)0.55666 (11)0.0146 (2)
C70.40703 (16)0.38347 (11)0.67825 (11)0.0149 (2)
H7A0.48300.36670.73620.018*
C80.25361 (15)0.46946 (11)0.69393 (10)0.0142 (2)
C90.15814 (15)0.55579 (11)0.79978 (11)0.0142 (2)
C100.24468 (16)0.55128 (11)0.91227 (11)0.0151 (2)
H10A0.20930.46500.97280.018*
H10B0.38490.55480.87580.018*
C110.24999 (15)0.68820 (12)1.07844 (11)0.0153 (2)
C120.17567 (15)0.81458 (11)1.14463 (11)0.0142 (2)
C130.19740 (15)0.94584 (12)1.07249 (11)0.0153 (2)
C140.11950 (16)1.06035 (12)1.13868 (12)0.0180 (2)
H14A0.13031.14961.09060.022*
C150.02584 (17)1.04355 (13)1.27532 (12)0.0206 (2)
H15A−0.02801.12201.31980.025*
C160.00940 (18)0.91521 (13)1.34781 (12)0.0212 (2)
H16A−0.05370.90541.44140.025*
C170.08654 (17)0.80078 (12)1.28184 (11)0.0180 (2)
H17A0.07820.71231.33100.022*
C180.33754 (19)1.08448 (13)0.86819 (12)0.0226 (2)
H18A0.42411.07580.77800.034*
H18B0.39551.14230.91450.034*
H18C0.21761.12700.86210.034*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0172 (4)0.0179 (4)0.0137 (4)0.0017 (3)−0.0075 (3)−0.0026 (3)
O20.0213 (4)0.0164 (4)0.0176 (4)0.0062 (3)−0.0112 (3)−0.0062 (3)
O30.0184 (4)0.0207 (4)0.0198 (4)0.0047 (3)−0.0093 (3)−0.0037 (3)
O40.0403 (6)0.0307 (5)0.0362 (5)0.0198 (4)−0.0288 (5)−0.0166 (4)
O50.0265 (4)0.0163 (4)0.0143 (4)−0.0002 (3)−0.0034 (3)0.0007 (3)
C10.0155 (5)0.0152 (5)0.0129 (5)−0.0015 (4)−0.0046 (4)−0.0013 (4)
C20.0209 (5)0.0230 (6)0.0147 (5)−0.0040 (4)−0.0075 (4)−0.0013 (4)
C30.0237 (6)0.0262 (6)0.0153 (5)−0.0050 (5)−0.0053 (4)−0.0056 (4)
C40.0234 (6)0.0234 (6)0.0201 (6)0.0007 (4)−0.0041 (4)−0.0086 (4)
C50.0197 (5)0.0202 (5)0.0201 (5)0.0025 (4)−0.0065 (4)−0.0046 (4)
C60.0167 (5)0.0141 (5)0.0129 (5)−0.0006 (4)−0.0048 (4)−0.0007 (4)
C70.0180 (5)0.0147 (5)0.0128 (5)0.0001 (4)−0.0063 (4)−0.0004 (4)
C80.0165 (5)0.0146 (5)0.0125 (5)−0.0009 (4)−0.0062 (4)−0.0005 (4)
C90.0161 (5)0.0136 (5)0.0133 (5)−0.0012 (4)−0.0053 (4)−0.0003 (4)
C100.0184 (5)0.0151 (5)0.0132 (5)0.0041 (4)−0.0068 (4)−0.0035 (4)
C110.0164 (5)0.0163 (5)0.0145 (5)0.0012 (4)−0.0070 (4)−0.0017 (4)
C120.0155 (5)0.0140 (5)0.0144 (5)0.0012 (4)−0.0065 (4)−0.0025 (4)
C130.0158 (5)0.0166 (5)0.0143 (5)0.0006 (4)−0.0061 (4)−0.0014 (4)
C140.0198 (5)0.0146 (5)0.0206 (5)0.0015 (4)−0.0076 (4)−0.0023 (4)
C150.0205 (5)0.0193 (5)0.0225 (6)0.0013 (4)−0.0059 (4)−0.0072 (4)
C160.0231 (5)0.0235 (6)0.0153 (5)−0.0011 (4)−0.0023 (4)−0.0050 (4)
C170.0207 (5)0.0172 (5)0.0160 (5)−0.0018 (4)−0.0056 (4)−0.0008 (4)
C180.0278 (6)0.0190 (5)0.0197 (5)−0.0041 (4)−0.0072 (5)0.0042 (4)
Geometric parameters (Å, º) top
O1—C11.3726 (13)C7—H7A0.9500
O1—C81.3817 (13)C8—C91.4591 (15)
O2—C111.3405 (13)C9—C101.5141 (15)
O2—C101.4352 (13)C10—H10A0.9900
O3—C91.2165 (13)C10—H10B0.9900
O4—C111.2013 (14)C11—C121.4854 (15)
O5—C131.3608 (13)C12—C171.3885 (15)
O5—C181.4278 (14)C12—C131.4029 (15)
C1—C21.3854 (15)C13—C141.3918 (15)
C1—C61.3968 (15)C14—C151.3891 (17)
C2—C31.3862 (17)C14—H14A0.9500
C2—H2A0.9500C15—C161.3811 (17)
C3—C41.4033 (18)C15—H15A0.9500
C3—H3A0.9500C16—C171.3888 (16)
C4—C51.3865 (17)C16—H16A0.9500
C4—H4A0.9500C17—H17A0.9500
C5—C61.3983 (15)C18—H18A0.9800
C5—H5A0.9500C18—H18B0.9800
C6—C71.4333 (15)C18—H18C0.9800
C7—C81.3589 (15)
C1—O1—C8105.39 (8)C9—C10—H10A110.3
C11—O2—C10114.70 (8)O2—C10—H10B110.3
C13—O5—C18116.85 (9)C9—C10—H10B110.3
O1—C1—C2125.19 (10)H10A—C10—H10B108.5
O1—C1—C6110.64 (9)O4—C11—O2123.18 (11)
C2—C1—C6124.16 (11)O4—C11—C12124.35 (10)
C1—C2—C3115.56 (11)O2—C11—C12112.37 (9)
C1—C2—H2A122.2C17—C12—C13120.00 (10)
C3—C2—H2A122.2C17—C12—C11118.36 (10)
C2—C3—C4122.01 (11)C13—C12—C11121.63 (10)
C2—C3—H3A119.0O5—C13—C14124.76 (10)
C4—C3—H3A119.0O5—C13—C12115.95 (10)
C5—C4—C3121.16 (11)C14—C13—C12119.25 (10)
C5—C4—H4A119.4C15—C14—C13119.68 (11)
C3—C4—H4A119.4C15—C14—H14A120.2
C4—C5—C6118.01 (11)C13—C14—H14A120.2
C4—C5—H5A121.0C16—C15—C14121.37 (11)
C6—C5—H5A121.0C16—C15—H15A119.3
C1—C6—C5119.09 (10)C14—C15—H15A119.3
C1—C6—C7105.80 (9)C15—C16—C17119.02 (11)
C5—C6—C7135.10 (11)C15—C16—H16A120.5
C8—C7—C6106.09 (9)C17—C16—H16A120.5
C8—C7—H7A127.0C12—C17—C16120.59 (11)
C6—C7—H7A127.0C12—C17—H17A119.7
C7—C8—O1112.07 (9)C16—C17—H17A119.7
C7—C8—C9131.43 (10)O5—C18—H18A109.5
O1—C8—C9116.50 (9)O5—C18—H18B109.5
O3—C9—C8122.38 (10)H18A—C18—H18B109.5
O3—C9—C10122.39 (10)O5—C18—H18C109.5
C8—C9—C10115.20 (9)H18A—C18—H18C109.5
O2—C10—C9107.13 (8)H18B—C18—H18C109.5
O2—C10—H10A110.3
C8—O1—C1—C2179.76 (10)C11—O2—C10—C9−173.51 (9)
C8—O1—C1—C6−0.15 (12)O3—C9—C10—O2−18.82 (14)
O1—C1—C2—C3179.82 (10)C8—C9—C10—O2163.15 (9)
C6—C1—C2—C3−0.28 (17)C10—O2—C11—O4−6.03 (17)
C1—C2—C3—C4−0.22 (17)C10—O2—C11—C12177.51 (9)
C2—C3—C4—C50.57 (19)O4—C11—C12—C17−55.50 (17)
C3—C4—C5—C6−0.42 (18)O2—C11—C12—C17120.91 (11)
O1—C1—C6—C5−179.67 (10)O4—C11—C12—C13123.09 (14)
C2—C1—C6—C50.42 (17)O2—C11—C12—C13−60.51 (14)
O1—C1—C6—C7−0.36 (12)C18—O5—C13—C142.08 (16)
C2—C1—C6—C7179.73 (10)C18—O5—C13—C12−175.45 (10)
C4—C5—C6—C1−0.05 (17)C17—C12—C13—O5174.12 (10)
C4—C5—C6—C7−179.11 (12)C11—C12—C13—O5−4.45 (15)
C1—C6—C7—C80.73 (12)C17—C12—C13—C14−3.55 (16)
C5—C6—C7—C8179.88 (13)C11—C12—C13—C14177.88 (10)
C6—C7—C8—O1−0.87 (12)O5—C13—C14—C15−175.85 (11)
C6—C7—C8—C9178.16 (11)C12—C13—C14—C151.60 (17)
C1—O1—C8—C70.65 (12)C13—C14—C15—C160.55 (18)
C1—O1—C8—C9−178.54 (9)C14—C15—C16—C17−0.74 (19)
C7—C8—C9—O3−177.25 (11)C13—C12—C17—C163.40 (17)
O1—C8—C9—O31.74 (16)C11—C12—C17—C16−177.99 (10)
C7—C8—C9—C100.77 (17)C15—C16—C17—C12−1.25 (18)
O1—C8—C9—C10179.77 (9)
Hydrogen-bond geometry (Å, º) top
Cg3 is the centroid of the C12–C17 ring.
D—H···AD—HH···AD···AD—H···A
C2—H2A···O3i0.952.453.2677 (15)145
C7—H7A···O4ii0.952.313.2352 (16)163
C10—H10A···O3iii0.992.553.3746 (14)141
C10—H10B···O4ii0.992.443.2028 (17)134
C17—H17A···O1iii0.952.553.2730 (15)134
C18—H18C···Cg3iv0.982.813.6181 (16)141
Symmetry codes: (i) −x, −y+1, −z+1; (ii) −x+1, −y+1, −z+2; (iii) −x, −y+1, −z+2; (iv) −x, −y+2, −z+2.
π–π interactions in compound (II). top
Centroid 1Centroid 2Centroid-to-centroid distance (Å)Symmetry code
Cg1Cg13.4402 (7)-x+1, -y+1, -z+1
Cg1Cg23.6088 (7)-x+1, -y+1, -z+1
Cg1 and Cg2 are the centroids of O1/C1/C6/C7/C8 and C1–C6 rings, respectively.

Acknowledgements

LYT thanks Universiti Sains Malaysia for USM Fellowship Scheme and the Malaysian Government for MyBrain15 (MyMaster) scholarship. HCK thanks the Malaysian Government for MyBrain15 (MyPhD) scholarship. The authors extend their appreciation to Vidya Vikas Research & Development Centre for the facilities and encouragement.

References

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ISSN: 2056-9890
Volume 73| Part 8| August 2017| Pages 1227-1231
https://doi.org/10.1107/S2056989017010556
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