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

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ISSN: 2056-9890

3-(3-Nitro­benz­yl)-4H-chromen-4-one

aSchool of Chemistry and Physics, University of KwaZulu-Natal, Private Bag X54001, Durban 4000, South Africa, bChemistry Department, University of Cape Town, Rondebosch 7701, South Africa, and cSchool of Chemical Engineering, University of KwaZulu-Natal, Durban 4041, South Africa
*Correspondence e-mail: koorbanally@ukzn.ac.za

(Received 31 January 2013; accepted 5 February 2013; online 9 February 2013)

In the title compound, C16H11NO4, the dihedral angle between the 10-membered coplanar chromone ring system and the benzene ring is 77.83 (3)°. In the crystal, weak C—H⋯O hydrogen bonds link the mol­ecules into a three-dimensional network.

Related literature

For the preparation, see: Valkonen et al. (2012[Valkonen, A., Laihia, K., Kolehmainen, E., Kauppinen, R. & Perjési, P. (2012). Struct. Chem. 23, 209-217.]). For related structures, see: Sievänen et al. (2010[Sievänen, E., Toušek, J., Lunerová, K., Marek, J., Jankovská, D., Dvorská, M. & Marek, R. (2010). J. Mol. Struct. 979, 172-179.]); Gopaul et al. (2012[Gopaul, K., Shaikh, M. M., Koorbanally, N. A., Ramjugernath, D. & Omondi, B. (2012). Acta Cryst. E68, o1972.]); Valkonen et al. (2012[Valkonen, A., Laihia, K., Kolehmainen, E., Kauppinen, R. & Perjési, P. (2012). Struct. Chem. 23, 209-217.]). For general background to homoisoflavoinoids, see: Shaikh et al. (2011[Shaikh, M., Petzold, K., Kruger, H. & du Toit, K. (2011). Struct. Chem. 22, 161-166.]); du Toit et al. (2010[Toit, K. du, Drewes, S. E. & Bodenstein, J. (2010). Nat. Prod. Res. 24, 457-490.]).

[Scheme 1]

Experimental

Crystal data
  • C16H11NO4

  • Mr = 281.26

  • Monoclinic, P 21 /c

  • a = 4.6082 (3) Å

  • b = 10.4219 (6) Å

  • c = 26.4468 (17) Å

  • β = 90.428 (1)°

  • V = 1270.10 (14) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.11 mm−1

  • T = 173 K

  • 0.42 × 0.22 × 0.04 mm

Data collection
  • Bruker Kappa DUO APEXII diffractometer

  • Absorption correction: multi-scan (SADABS; Sheldrick, 1997[Sheldrick, G. M. (1997). SADABS. University of Göttingen, Germany.]) Tmin = 0.956, Tmax = 0.996

  • 16973 measured reflections

  • 4246 independent reflections

  • 3069 reflections with I > 2σ(I)

  • Rint = 0.030

Refinement
  • R[F2 > 2σ(F2)] = 0.047

  • wR(F2) = 0.138

  • S = 1.04

  • 4246 reflections

  • 190 parameters

  • H-atom parameters constrained

  • Δρmax = 0.44 e Å−3

  • Δρmin = −0.19 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
C2—H2⋯O2 0.95 2.32 3.2663 (15) 171
C7—H7⋯O3i 0.95 2.65 3.5614 (19) 160
C8—H8⋯O3ii 0.95 2.54 3.3071 (18) 138
C14—H14⋯O4iii 0.95 2.50 3.4380 (17) 172
C15—H15⋯O1iv 0.95 2.62 3.5569 (15) 170
C16—H16⋯O2v 0.95 2.46 3.3764 (15) 163
Symmetry codes: (i) [-x, y+{\script{1\over 2}}, -z+{\script{1\over 2}}]; (ii) [x+1, -y+{\script{3\over 2}}, z-{\script{1\over 2}}]; (iii) -x+1, -y+2, -z+1; (iv) [-x+2, y+{\script{1\over 2}}, -z+{\script{1\over 2}}]; (v) x+1, y, z.

Data collection: APEX2 (Bruker, 2006[Bruker (2006). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2006[Bruker (2006). APEX2 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 (Farrugia, 2012[Farrugia, L. J. (2012). J. Appl. Cryst. 45, 849-854.]); software used to prepare material for publication: SHELXL97.

Supporting information


Comment top

The title compound, 3-(3-nitrobenzyl)-2-chromen-4-one, belongs to a class of compounds called homoisoflavonoids, which are C-16, α,β unsaturated carbonyl compounds containing two aromatic rings. Homoisoflavonoids may be categorized into four groups depending on the type of structural backbone present. The four groups are 3-benzyl-4-chromanones, of which the title compound belongs to as well as the, 3-benzylidene-4-chromanones, 3-benzyl-3-hydroxy-4-chromanones and scillascillins (du Toit et al., 2010). The most commonly used procedure for the synthesis of homoisoflavoinoids involves the condensation of chroman-4-one with an aromatic aldehyde in the presence of either an acidic or basic catalyst (Shaikh et al., 2011).

The molecular structure of the title compound is shown in Fig.1. The dihedral angle between the 10-membered co-planar ring O1—C1—C9—C8—C7—C6—C5—C4—C3—C2 and the benzene ring C11—C12—C13—C14—C15—C16 is 77.83 (3)°. In the crystal packing, a number of weak intermolecular C—H···O hydrogen bonds are noted and are listed in Table 1.

Related literature top

For the preparation, see: Valkonen et al. (2012). For related structures, see: Sievänen et al. (2010); Gopaul et al. (2012); Valkonen et al. (2012). For general background to homoisoflavoinoids, see: Shaikh et al. (2011); du Toit et al. (2010).

Experimental top

A mixture of chroman-4-one (1.00 g, 6.75 mmol), 3-nitrobenzaldehyde (1.25 g, 8.10 mmol) and 10–15 drops of piperidine was heated at 80°C for 10 hrs. The reaction mixture was monitored for completion by thin layer chromatography. Upon completion, the reaction mixture was cooled, diluted with water and neutralized using 10% HCl. To the viscous reaction mixture, 15 ml of ethyl acetate was added. The homoisoflavonoid precipitated out upon the addition of hexane to the reaction mixture. The powdered product was filtered, washed with hexane and dried under vacuum. Upon slow evaporation of chloroform, the crystals of the homoisoflavonoid were obtained with a m.p. of 129–130 °C.

Refinement top

All non-hydrogen atoms were refined anisotropically. All hydrogen atoms were placed in idealized positions and refined with geometrical constraints, and with Uiso(H) = 1.2Ueq(C).

Computing details top

Data collection: APEX2 (Bruker, 2006); cell refinement: SAINT (Bruker, 2006); data reduction: SAINT (Bruker, 2006); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 2012); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. A view of the molecule with displacement ellipsoids drawn at the 50% probability level and H atoms drawn as circles of arbitary size.
3-(3-Nitrobenzyl)-4H-chromen-4-one top
Crystal data top
C16H11NO4F(000) = 584
Mr = 281.26Dx = 1.471 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
a = 4.6082 (3) ÅCell parameters from 16973 reflections
b = 10.4219 (6) Åθ = 1.5–31.6°
c = 26.4468 (17) ŵ = 0.11 mm1
β = 90.428 (1)°T = 173 K
V = 1270.10 (14) Å3Plate, colourless
Z = 40.42 × 0.22 × 0.04 mm
Data collection top
Bruker Kappa DUO APEXII
diffractometer
4246 independent reflections
Radiation source: fine-focus sealed tube3069 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.030
0.5° ϕ scans and ω scansθmax = 31.6°, θmin = 1.5°
Absorption correction: multi-scan
(SADABS; Sheldrick, 1997)
h = 36
Tmin = 0.956, Tmax = 0.996k = 1215
16973 measured reflectionsl = 3836
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)] = 0.047Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.138H-atom parameters constrained
S = 1.04 w = 1/[σ2(Fo2) + (0.0728P)2 + 0.2299P]
where P = (Fo2 + 2Fc2)/3
4246 reflections(Δ/σ)max < 0.001
190 parametersΔρmax = 0.44 e Å3
0 restraintsΔρmin = 0.19 e Å3
Crystal data top
C16H11NO4V = 1270.10 (14) Å3
Mr = 281.26Z = 4
Monoclinic, P21/cMo Kα radiation
a = 4.6082 (3) ŵ = 0.11 mm1
b = 10.4219 (6) ÅT = 173 K
c = 26.4468 (17) Å0.42 × 0.22 × 0.04 mm
β = 90.428 (1)°
Data collection top
Bruker Kappa DUO APEXII
diffractometer
4246 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 1997)
3069 reflections with I > 2σ(I)
Tmin = 0.956, Tmax = 0.996Rint = 0.030
16973 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0470 restraints
wR(F2) = 0.138H-atom parameters constrained
S = 1.04Δρmax = 0.44 e Å3
4246 reflectionsΔρmin = 0.19 e Å3
190 parameters
Special details top

Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'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 > σ(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
O10.74839 (19)0.65066 (9)0.16340 (3)0.0297 (2)
O20.12234 (19)0.86867 (9)0.23054 (3)0.0307 (2)
O30.0611 (3)0.69688 (13)0.46889 (4)0.0563 (4)
O40.2296 (3)0.87629 (13)0.49596 (4)0.0569 (3)
N10.2075 (3)0.79369 (12)0.46362 (4)0.0364 (3)
C10.6196 (2)0.74864 (12)0.13678 (4)0.0254 (2)
C20.6533 (3)0.62632 (12)0.21073 (5)0.0281 (2)
H20.73930.55620.22820.034*
C30.4471 (3)0.69311 (11)0.23514 (4)0.0243 (2)
C40.3094 (2)0.80163 (11)0.21004 (4)0.0229 (2)
C50.4068 (2)0.82546 (11)0.15828 (4)0.0228 (2)
C60.2875 (3)0.92474 (12)0.12884 (5)0.0304 (3)
H60.14130.97830.14260.037*
C70.3805 (3)0.94494 (15)0.08021 (5)0.0380 (3)
H70.29991.01270.06060.046*
C80.5929 (3)0.86601 (16)0.05974 (5)0.0392 (3)
H80.65590.88060.02610.047*
C90.7132 (3)0.76728 (14)0.08729 (5)0.0343 (3)
H90.85650.71310.07300.041*
C100.3523 (3)0.65438 (12)0.28725 (5)0.0303 (3)
H10A0.43650.56910.29490.036*
H10B0.13860.64460.28680.036*
C110.4334 (2)0.74495 (11)0.32985 (4)0.0238 (2)
C120.2953 (3)0.72947 (12)0.37618 (4)0.0265 (2)
H120.15540.66350.38050.032*
C130.3633 (3)0.81075 (12)0.41575 (4)0.0261 (2)
C140.5657 (3)0.90853 (12)0.41192 (5)0.0292 (3)
H140.60650.96400.43960.035*
C150.7057 (3)0.92194 (12)0.36619 (5)0.0305 (3)
H150.84820.98710.36240.037*
C160.6411 (3)0.84133 (12)0.32557 (5)0.0265 (2)
H160.74020.85230.29450.032*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0335 (4)0.0285 (4)0.0271 (4)0.0059 (3)0.0036 (3)0.0029 (3)
O20.0348 (5)0.0295 (5)0.0280 (5)0.0034 (4)0.0080 (3)0.0026 (4)
O30.0700 (8)0.0657 (8)0.0335 (6)0.0301 (6)0.0160 (5)0.0001 (5)
O40.0765 (8)0.0620 (8)0.0325 (6)0.0123 (6)0.0152 (5)0.0182 (5)
N10.0398 (6)0.0462 (7)0.0233 (5)0.0044 (5)0.0039 (4)0.0002 (5)
C10.0279 (5)0.0265 (5)0.0218 (5)0.0018 (4)0.0010 (4)0.0024 (4)
C20.0361 (6)0.0226 (5)0.0256 (6)0.0018 (5)0.0035 (4)0.0009 (4)
C30.0329 (6)0.0202 (5)0.0198 (5)0.0043 (4)0.0007 (4)0.0008 (4)
C40.0267 (5)0.0210 (5)0.0212 (5)0.0042 (4)0.0020 (4)0.0018 (4)
C50.0264 (5)0.0227 (5)0.0194 (5)0.0023 (4)0.0010 (4)0.0003 (4)
C60.0347 (6)0.0291 (6)0.0275 (6)0.0014 (5)0.0007 (5)0.0044 (5)
C70.0466 (8)0.0399 (7)0.0274 (7)0.0025 (6)0.0010 (5)0.0105 (6)
C80.0419 (7)0.0533 (9)0.0224 (6)0.0078 (6)0.0056 (5)0.0041 (6)
C90.0349 (6)0.0434 (7)0.0247 (6)0.0021 (6)0.0073 (5)0.0057 (5)
C100.0455 (7)0.0238 (5)0.0215 (6)0.0092 (5)0.0003 (5)0.0012 (4)
C110.0289 (5)0.0220 (5)0.0206 (5)0.0007 (4)0.0010 (4)0.0018 (4)
C120.0298 (5)0.0269 (5)0.0230 (6)0.0058 (4)0.0002 (4)0.0028 (4)
C130.0296 (5)0.0297 (6)0.0191 (5)0.0006 (4)0.0012 (4)0.0014 (4)
C140.0333 (6)0.0275 (6)0.0269 (6)0.0015 (5)0.0029 (5)0.0036 (5)
C150.0317 (6)0.0286 (6)0.0312 (6)0.0080 (5)0.0001 (5)0.0004 (5)
C160.0287 (5)0.0265 (5)0.0243 (6)0.0029 (4)0.0021 (4)0.0010 (4)
Geometric parameters (Å, º) top
O1—C21.3533 (15)C7—H70.9500
O1—C11.3727 (15)C8—C91.375 (2)
O2—C41.2377 (14)C8—H80.9500
O3—N11.2222 (17)C9—H90.9500
O4—N11.2172 (16)C10—C111.5145 (16)
N1—C131.4709 (16)C10—H10A0.9900
C1—C51.3905 (16)C10—H10B0.9900
C1—C91.3949 (17)C11—C161.3926 (16)
C2—C31.3467 (17)C11—C121.3942 (16)
C2—H20.9500C12—C131.3804 (17)
C3—C41.4546 (16)C12—H120.9500
C3—C101.5042 (16)C13—C141.3858 (18)
C4—C51.4650 (15)C14—C151.3823 (18)
C5—C61.4047 (17)C14—H140.9500
C6—C71.3748 (18)C15—C161.3941 (17)
C6—H60.9500C15—H150.9500
C7—C81.391 (2)C16—H160.9500
C2—O1—C1118.16 (9)C8—C9—C1118.37 (12)
O4—N1—O3123.17 (12)C8—C9—H9120.8
O4—N1—C13118.71 (12)C1—C9—H9120.8
O3—N1—C13118.12 (12)C3—C10—C11116.27 (10)
O1—C1—C5121.47 (10)C3—C10—H10A108.2
O1—C1—C9116.69 (11)C11—C10—H10A108.2
C5—C1—C9121.83 (12)C3—C10—H10B108.2
C3—C2—O1125.53 (11)C11—C10—H10B108.2
C3—C2—H2117.2H10A—C10—H10B107.4
O1—C2—H2117.2C16—C11—C12118.25 (11)
C2—C3—C4119.35 (11)C16—C11—C10123.71 (11)
C2—C3—C10120.76 (11)C12—C11—C10118.03 (10)
C4—C3—C10119.87 (10)C13—C12—C11119.51 (11)
O2—C4—C3122.81 (10)C13—C12—H12120.2
O2—C4—C5122.20 (11)C11—C12—H12120.2
C3—C4—C5114.98 (10)C12—C13—C14123.03 (11)
C1—C5—C6118.15 (11)C12—C13—N1117.96 (11)
C1—C5—C4120.43 (10)C14—C13—N1119.00 (11)
C6—C5—C4121.42 (11)C15—C14—C13117.20 (11)
C7—C6—C5120.52 (12)C15—C14—H14121.4
C7—C6—H6119.7C13—C14—H14121.4
C5—C6—H6119.7C14—C15—C16120.98 (11)
C6—C7—C8119.91 (13)C14—C15—H15119.5
C6—C7—H7120.0C16—C15—H15119.5
C8—C7—H7120.0C11—C16—C15121.00 (11)
C9—C8—C7121.22 (12)C11—C16—H16119.5
C9—C8—H8119.4C15—C16—H16119.5
C7—C8—H8119.4
C2—O1—C1—C53.07 (16)C7—C8—C9—C10.7 (2)
C2—O1—C1—C9177.07 (11)O1—C1—C9—C8178.84 (12)
C1—O1—C2—C32.33 (18)C5—C1—C9—C81.02 (19)
O1—C2—C3—C40.18 (19)C2—C3—C10—C11111.41 (14)
O1—C2—C3—C10178.04 (11)C4—C3—C10—C1170.37 (15)
C2—C3—C4—O2178.62 (11)C3—C10—C11—C1615.66 (18)
C10—C3—C4—O23.14 (17)C3—C10—C11—C12165.39 (11)
C2—C3—C4—C51.83 (16)C16—C11—C12—C131.26 (17)
C10—C3—C4—C5176.41 (10)C10—C11—C12—C13179.73 (11)
O1—C1—C5—C6179.30 (11)C11—C12—C13—C140.19 (19)
C9—C1—C5—C60.55 (18)C11—C12—C13—N1178.39 (11)
O1—C1—C5—C41.39 (17)O4—N1—C13—C12168.33 (13)
C9—C1—C5—C4178.76 (11)O3—N1—C13—C1211.53 (19)
O2—C4—C5—C1179.38 (11)O4—N1—C13—C1410.31 (19)
C3—C4—C5—C11.07 (15)O3—N1—C13—C14169.83 (13)
O2—C4—C5—C61.33 (18)C12—C13—C14—C150.96 (19)
C3—C4—C5—C6178.22 (11)N1—C13—C14—C15179.52 (12)
C1—C5—C6—C70.23 (19)C13—C14—C15—C161.02 (19)
C4—C5—C6—C7179.53 (12)C12—C11—C16—C151.20 (18)
C5—C6—C7—C80.5 (2)C10—C11—C16—C15179.86 (12)
C6—C7—C8—C90.0 (2)C14—C15—C16—C110.0 (2)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C2—H2···O20.952.323.2663 (15)171
C7—H7···O3i0.952.653.5614 (19)160
C8—H8···O3ii0.952.543.3071 (18)138
C14—H14···O4iii0.952.503.4380 (17)172
C15—H15···O1iv0.952.623.5569 (15)170
C16—H16···O2v0.952.463.3764 (15)163
Symmetry codes: (i) x, y+1/2, z+1/2; (ii) x+1, y+3/2, z1/2; (iii) x+1, y+2, z+1; (iv) x+2, y+1/2, z+1/2; (v) x+1, y, z.

Experimental details

Crystal data
Chemical formulaC16H11NO4
Mr281.26
Crystal system, space groupMonoclinic, P21/c
Temperature (K)173
a, b, c (Å)4.6082 (3), 10.4219 (6), 26.4468 (17)
β (°) 90.428 (1)
V3)1270.10 (14)
Z4
Radiation typeMo Kα
µ (mm1)0.11
Crystal size (mm)0.42 × 0.22 × 0.04
Data collection
DiffractometerBruker Kappa DUO APEXII
diffractometer
Absorption correctionMulti-scan
(SADABS; Sheldrick, 1997)
Tmin, Tmax0.956, 0.996
No. of measured, independent and
observed [I > 2σ(I)] reflections
16973, 4246, 3069
Rint0.030
(sin θ/λ)max1)0.736
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.047, 0.138, 1.04
No. of reflections4246
No. of parameters190
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.44, 0.19

Computer programs: APEX2 (Bruker, 2006), SAINT (Bruker, 2006), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 2012).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C2—H2···O20.952.323.2663 (15)170.8
C7—H7···O3i0.952.653.5614 (19)160.0
C8—H8···O3ii0.952.543.3071 (18)137.5
C14—H14···O4iii0.952.503.4380 (17)171.5
C15—H15···O1iv0.952.623.5569 (15)170.4
C16—H16···O2v0.952.463.3764 (15)162.9
Symmetry codes: (i) x, y+1/2, z+1/2; (ii) x+1, y+3/2, z1/2; (iii) x+1, y+2, z+1; (iv) x+2, y+1/2, z+1/2; (v) x+1, y, z.
 

Acknowledgements

We thank the University of KwaZulu-Natal and the South Africa Research Chairs initiative of the Department of Science and Technology for financial support and the National Research Foundation of South Africa for a bursary for KG.

References

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