supplementary materials


zs2259 scheme

Acta Cryst. (2013). E69, o1011-o1012    [ doi:10.1107/S1600536813014645 ]

rac-3-(4-Hydroxybenzyl)chroman-4-one

S. Shalini, C. R. Girija, L. Simon, K. K. Srinivasan and T. V. Venkatesha

Abstract top

In the racemic title compound, C16H14O3, the ring of the 4-hydroxybenzyl substituent group forms a dihedral angle of 80.12 (12)° with the benzene ring of the chromanone system. Two C atoms of the pyranone ring and the H atoms on the benzyl [alpha]-C atom are disordered over two sites, with site-occupation factors of 0.818 (8) and 0.182 (8). The crystal structure is stabilized by O-H...O hydrogen bonds, which form parallel one-dimensional zigzag chains down the c axis and are interconnected by both methine C-H...O hydrogen bonds and weak aromatic C-H...[pi] interactions, giving a sheet structure lying parallel to [011].

Comment top

Naturally occurring homoisoflavanones that possess a 3-benzyl-substituted chroman ring system as a common framework have been isolated from a wide range of natural sources and exhibit a variety of biological activities (Wera et al. (2011). Here we report the structure of the racemic chroman-4-one benzyl derivative, C16H14O3, in which the phenyl ring of the 4-hydroxybenzyl substituent group forms a dihedral angle of 80.12 (12)° with the phenyl ring of the chromanone ring (Fig. 1). The ring-puckering parameters q2 = 0.3745 (0) Å, q3 = -0.2819 (0) Å, QT = 0.4688 Å and φ = -144.45 (0)° of the 2,3-dihydro-4H-chroman-4-one ring are indicative of an envelope conformation. Two carbon atoms of the pyranone ring (C8 and C9) with the hydrogen atoms of the benzyl C-atom (C7) are disordered over two sites with site-occupation factors of 0.818 (8) (C8, C9) and 0.182 (8) (C8' C9').

In the crystal a strong intermolecular hydrogen bond (O1—H1···O2i) (Table 1) results in the formation of one-dimensional zigzag chains which extend along c (Fig. 2). Weak intermolecular methine C8—H···O1ii hydrogen bonds and weak aromatic C16—H···π (C1–C6)iii interactions [H···Cg = 3.139 Å] [symmetry code (iii) x, y - 1, z] give sheets extending along [011]. There are no ππ stacking interactions present in the structure.

Related literature top

For general background on the properties of isoflavanones (derivatives of 3-benzyl-4H-chromen-4-one), see: Klymchenko et al. (2003); Sengupta & Kasha (1979). For related structures, see: Etter et al. (1986); Waller et al. (2003); Wera et al. (2011); Shalini et al. (2013). For intermolecular interactions, see: Takahashi et al. (2001). For ring-puckering calculations, see: Cremer & Pople (1975).

Experimental top

In the preparation of the title compound, 2'-hydroxydihydrochalcone (0.1 g, 1 equivalent) was dissolved in ethanol (10 ml) was refluxed with paraformaldehyde (0.022 g, 2 equivalents) and 50% aqueous diethylamine (0.2 ml, 1 equivalent) for 7 h. Ethanol was distilled off and the residue was taken up in ethyl acetate. The ethyl acetate layer was washed with water and then with dilute HCL. Ethyl acetate was distilled off and the oily residue was column-chromatographed over silica using petroleum ether:ethyl acetate (7:3) as eluent to obtain the title compound in 60–70% yield. Colourless single crystals were grown in ethanol by slow evaporation at ambient temperature. Spectroscopy: IR (cm-1): 3282 (O—H str), 1672 (CO str), 1604 (CC str); mass (m/z): M+ 254 (70%), 237, 147 (100%), 121; 1H NMR (400 MHz,solvent DMSO): δ 4.3 (dd, J = 11.6, 4.4 Hz, 1H, 2-H), δ 4.1 (dd, J = 16, 8.8 Hz, 1H, 2-H), δ 2.5 (m, 1H, 3-H), δ 3 (m, 2H, 9-H), δ 7.7 (dd, J = 7.6, 1.2 Hz, 1H), δ 7.5 (m, 1H), δ 7 (m, 3H, Ar—H), δ 6.6 (d, J = 8.4 Hz, 2H, Ar—H)

Refinement top

Carbon-bound H atoms were positioned geometrically, with C—H = 0.93 Å (aromatic), 0.98 Å (methine) and 0.97 Å (methylene), and were constrained to ride on their parent atoms with Uiso(H) = 1.2Ueq(C). The phenolic H atom was located in a difference Fourier map and was also allowed to ride with Uiso(H) = 1.2Ueq(O). In the refinement, positional, site-occupation factors and Uij parameters of the disordered C atoms [C8, C9 = 0.818 (8) and C8', C9' = 0.112 (8)] were refined freely. However, the EADP instruction (Sheldrick, 2008) was used to constrain the anisotropic displacement parameters (ADPs) of the disordered C atoms of the minor components to the same values as the corresponding C atoms in the principal component. Also, SUMP and DFIX restraints were used to stabilize the refinement of the disordered atoms. The occupancies of the disordered components were fixed during the final cycles of the refinement.

Computing details top

Data collection: APEX2 (Bruker, 2004); cell refinement: APEX2 and SAINT (Bruker, 2004); data reduction: SAINT and XPREP (Bruker, 2004); program(s) used to solve structure: SIR92 (Altomare et al., 1993); 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. The molecular structure of the title compound, showing the atom-labelling scheme. Displacement ellipsoids are drawn at the 40% probability level.
[Figure 2] Fig. 2. The intermolecular interactions, viewed down the a cell direction. The O—H···O and C—H···π hydrogen bonds are represented by dashed lines and the minor disordered atoms C8' and C9' are not shown.
rac-3-(4-Hydroxybenzyl)chroman-4-one top
Crystal data top
C16H14O3F(000) = 536
Mr = 254.27Dx = 1.297 Mg m3
Monoclinic, P21/nMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ynCell parameters from 3775 reflections
a = 5.2570 (2) Åθ = 2.5–23.5°
b = 17.0254 (7) ŵ = 0.09 mm1
c = 14.6879 (5) ÅT = 293 K
β = 97.806 (2)°Block, colourless
V = 1302.42 (9) Å30.30 × 0.20 × 0.20 mm
Z = 4
Data collection top
Bruker Kappa APEX2 CCD
diffractometer
2288 independent reflections
Radiation source: fine-focus sealed tube1523 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.026
ω and φ scanθmax = 25.0°, θmin = 2.4°
Absorption correction: multi-scan
(SADABS; Bruker, 2004)
h = 66
Tmin = 0.962, Tmax = 0.991k = 1720
12297 measured reflectionsl = 1717
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.041H-atom parameters constrained
wR(F2) = 0.110 w = 1/[σ2(Fo2) + (0.0283P)2 + 0.4082P]
where P = (Fo2 + 2Fc2)/3
S = 1.11(Δ/σ)max = 0.001
2288 reflectionsΔρmax = 0.13 e Å3
187 parametersΔρmin = 0.11 e Å3
5 restraintsExtinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.0066 (15)
Crystal data top
C16H14O3V = 1302.42 (9) Å3
Mr = 254.27Z = 4
Monoclinic, P21/nMo Kα radiation
a = 5.2570 (2) ŵ = 0.09 mm1
b = 17.0254 (7) ÅT = 293 K
c = 14.6879 (5) Å0.30 × 0.20 × 0.20 mm
β = 97.806 (2)°
Data collection top
Bruker Kappa APEX2 CCD
diffractometer
2288 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2004)
1523 reflections with I > 2σ(I)
Tmin = 0.962, Tmax = 0.991Rint = 0.026
12297 measured reflectionsθmax = 25.0°
Refinement top
R[F2 > 2σ(F2)] = 0.041H-atom parameters constrained
wR(F2) = 0.110Δρmax = 0.13 e Å3
S = 1.11Δρmin = 0.11 e Å3
2288 reflectionsAbsolute structure: ?
187 parametersAbsolute structure parameter: ?
5 restraintsRogers parameter: ?
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*/UeqOcc. (<1)
C11.4022 (4)0.27353 (12)1.13065 (15)0.0628 (6)
C21.2332 (4)0.28490 (13)1.05275 (15)0.0717 (6)
H21.09320.31821.05340.086*
C31.2717 (5)0.24661 (14)0.97306 (15)0.0768 (7)
H31.15650.25510.92010.092*
C41.4740 (4)0.19636 (12)0.96916 (14)0.0620 (6)
C51.6411 (4)0.18607 (13)1.04841 (16)0.0685 (6)
H51.78070.15261.04810.082*
C61.6067 (4)0.22434 (14)1.12857 (16)0.0741 (6)
H61.72300.21661.18140.089*
C71.5106 (4)0.15507 (15)0.88088 (15)0.0770 (7)
H7A1.66940.12530.89060.092*0.818 (8)
H7B1.52720.19420.83400.092*0.818 (8)
H7C1.69380.14730.88200.092*0.182 (8)
H7D1.45700.19150.83120.092*0.182 (8)
C81.2935 (8)0.10032 (19)0.8465 (2)0.0608 (9)0.818 (8)
H81.13650.13200.83890.073*0.818 (8)
C91.2480 (9)0.0336 (3)0.9090 (2)0.0726 (11)0.818 (8)
H9A1.23810.05430.97000.087*0.818 (8)
H9B1.39370.00180.91350.087*0.818 (8)
C8'1.387 (3)0.0801 (8)0.8553 (13)0.0608 (9)0.182 (8)
H8'1.50450.03830.88030.073*0.182 (8)
C9'1.146 (3)0.0730 (10)0.8989 (10)0.058 (4)0.182 (8)
H9'11.18520.08110.96460.070*0.182 (8)
H9'21.02460.11300.87420.070*0.182 (8)
C101.0010 (4)0.03237 (13)0.79097 (18)0.0718 (6)
C111.1423 (4)0.00044 (12)0.72734 (15)0.0671 (6)
C121.3175 (4)0.06544 (13)0.75340 (15)0.0662 (6)
C131.1050 (6)0.02833 (16)0.63788 (18)0.0956 (8)
H131.19880.00740.59430.115*
C140.9319 (7)0.0870 (2)0.6134 (3)0.1193 (11)
H140.90710.10570.55340.143*
C150.7942 (7)0.11842 (19)0.6781 (3)0.1237 (12)
H150.67690.15840.66120.148*
C160.8271 (5)0.09181 (16)0.7663 (2)0.0994 (9)
H160.73330.11350.80940.119*
O11.3727 (3)0.30821 (10)1.21218 (10)0.0888 (6)
H11.24350.33571.20550.107*
O21.4570 (3)0.09234 (10)0.70136 (10)0.0866 (5)
O31.0259 (3)0.00860 (9)0.88004 (12)0.0819 (5)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0626 (13)0.0639 (14)0.0646 (13)0.0046 (11)0.0181 (11)0.0075 (11)
C20.0703 (14)0.0750 (15)0.0719 (15)0.0148 (11)0.0176 (12)0.0028 (12)
C30.0750 (15)0.0922 (17)0.0625 (14)0.0139 (13)0.0072 (11)0.0019 (12)
C40.0578 (12)0.0648 (14)0.0667 (14)0.0074 (10)0.0207 (11)0.0064 (11)
C50.0550 (12)0.0682 (15)0.0841 (16)0.0017 (10)0.0156 (11)0.0113 (12)
C60.0676 (14)0.0841 (17)0.0685 (14)0.0034 (12)0.0015 (11)0.0076 (12)
C70.0683 (14)0.0928 (17)0.0747 (15)0.0110 (13)0.0278 (12)0.0168 (13)
C80.074 (2)0.0546 (17)0.0585 (15)0.0042 (14)0.0242 (17)0.0011 (14)
C90.079 (3)0.080 (3)0.0608 (18)0.007 (2)0.0166 (17)0.0059 (18)
C8'0.074 (2)0.0546 (17)0.0585 (15)0.0042 (14)0.0242 (17)0.0011 (14)
C9'0.061 (8)0.054 (10)0.065 (8)0.009 (6)0.022 (7)0.008 (7)
C100.0660 (14)0.0589 (14)0.0909 (18)0.0062 (11)0.0119 (13)0.0013 (13)
C110.0734 (14)0.0571 (13)0.0708 (15)0.0064 (11)0.0097 (11)0.0041 (11)
C120.0796 (15)0.0618 (14)0.0610 (13)0.0042 (11)0.0229 (12)0.0044 (11)
C130.118 (2)0.0855 (19)0.0816 (18)0.0047 (17)0.0078 (15)0.0140 (15)
C140.134 (3)0.096 (2)0.119 (3)0.002 (2)0.017 (2)0.036 (2)
C150.108 (3)0.080 (2)0.173 (4)0.0091 (18)0.016 (3)0.024 (2)
C160.0839 (19)0.0734 (18)0.140 (3)0.0107 (15)0.0117 (18)0.0041 (18)
O10.0925 (12)0.1042 (13)0.0711 (10)0.0090 (9)0.0164 (9)0.0248 (9)
O20.1092 (13)0.0882 (12)0.0706 (10)0.0128 (10)0.0413 (9)0.0031 (9)
O30.0861 (12)0.0782 (11)0.0868 (12)0.0134 (9)0.0308 (9)0.0065 (9)
Geometric parameters (Å, º) top
C1—O11.363 (2)C9—H9A0.9700
C1—C21.364 (3)C9—H9B0.9700
C1—C61.366 (3)C8'—C9'1.501 (10)
C2—C31.379 (3)C8'—C121.513 (18)
C2—H20.9300C8'—H8'0.9800
C3—C41.372 (3)C9'—O31.535 (15)
C3—H30.9300C9'—H9'10.9700
C4—C51.371 (3)C9'—H9'20.9700
C4—C71.510 (3)C10—O31.359 (3)
C5—C61.379 (3)C10—C161.379 (3)
C5—H50.9300C10—C111.388 (3)
C6—H60.9300C11—C131.391 (3)
C7—C8'1.457 (9)C11—C121.457 (3)
C7—C81.507 (4)C12—O21.218 (2)
C7—H7A0.9700C13—C141.366 (4)
C7—H7B0.9700C13—H130.9300
C7—H7C0.9700C14—C151.378 (4)
C7—H7D0.9700C14—H140.9300
C8—C91.500 (4)C15—C161.361 (4)
C8—C121.512 (4)C15—H150.9300
C8—H80.9800C16—H160.9300
C9—O31.388 (4)O1—H10.8200
O1—C1—C2122.4 (2)O3—C9—H9A108.8
O1—C1—C6118.0 (2)C8—C9—H9A108.8
C2—C1—C6119.6 (2)O3—C9—H9B108.8
C1—C2—C3119.4 (2)C8—C9—H9B108.8
C1—C2—H2120.3H9A—C9—H9B107.7
C3—C2—H2120.3C7—C8'—C9'109.5 (10)
C4—C3—C2122.3 (2)C7—C8'—C12116.1 (11)
C4—C3—H3118.8C9'—C8'—C12107.6 (12)
C2—C3—H3118.8C7—C8'—H8'107.8
C5—C4—C3117.1 (2)C9'—C8'—H8'107.8
C5—C4—C7121.8 (2)C12—C8'—H8'107.8
C3—C4—C7121.1 (2)C8'—C9'—O3110.4 (10)
C4—C5—C6121.4 (2)C8'—C9'—H9'1109.6
C4—C5—H5119.3O3—C9'—H9'1109.6
C6—C5—H5119.3C8'—C9'—H9'2109.6
C1—C6—C5120.2 (2)O3—C9'—H9'2109.6
C1—C6—H6119.9H9'1—C9'—H9'2108.1
C5—C6—H6119.9O3—C10—C16116.5 (2)
C8'—C7—C4121.6 (6)O3—C10—C11122.6 (2)
C8—C7—C4113.3 (2)C16—C10—C11121.0 (3)
C8'—C7—H7A85.7C10—C11—C13118.3 (2)
C8—C7—H7A108.9C10—C11—C12120.4 (2)
C4—C7—H7A108.9C13—C11—C12121.2 (2)
C8'—C7—H7B119.9O2—C12—C11122.2 (2)
C8—C7—H7B108.9O2—C12—C8123.4 (2)
C4—C7—H7B108.9C11—C12—C8114.1 (2)
H7A—C7—H7B107.7O2—C12—C8'118.2 (4)
C8'—C7—H7C106.9C11—C12—C8'116.4 (4)
C8—C7—H7C128.8C14—C13—C11120.6 (3)
C4—C7—H7C106.9C14—C13—H13119.7
H7B—C7—H7C85.5C11—C13—H13119.7
C8'—C7—H7D107.0C13—C14—C15119.8 (3)
C8—C7—H7D90.8C13—C14—H14120.1
C4—C7—H7D106.9C15—C14—H14120.1
H7A—C7—H7D126.9C16—C15—C14121.1 (3)
H7C—C7—H7D106.7C16—C15—H15119.5
C9—C8—C7116.1 (3)C14—C15—H15119.5
C9—C8—C12107.2 (3)C15—C16—C10119.3 (3)
C7—C8—C12113.2 (3)C15—C16—H16120.4
C9—C8—H8106.6C10—C16—H16120.4
C7—C8—H8106.6C1—O1—H1109.5
C12—C8—H8106.6C10—O3—C9114.6 (2)
O3—C9—C8113.7 (3)C10—O3—C9'115.2 (5)
O1—C1—C2—C3178.6 (2)C10—C11—C12—C89.9 (3)
C6—C1—C2—C30.1 (3)C13—C11—C12—C8167.7 (3)
C1—C2—C3—C40.7 (4)C10—C11—C12—C8'15.4 (8)
C2—C3—C4—C50.7 (3)C13—C11—C12—C8'167.0 (7)
C2—C3—C4—C7179.8 (2)C9—C8—C12—O2146.6 (3)
C3—C4—C5—C60.2 (3)C7—C8—C12—O217.2 (4)
C7—C4—C5—C6179.7 (2)C9—C8—C12—C1138.5 (5)
O1—C1—C6—C5178.2 (2)C7—C8—C12—C11167.8 (2)
C2—C1—C6—C50.4 (3)C9—C8—C12—C8'62.8 (11)
C4—C5—C6—C10.3 (3)C7—C8—C12—C8'66.6 (12)
C5—C4—C7—C8'93.3 (10)C7—C8'—C12—O233.5 (13)
C3—C4—C7—C8'87.3 (10)C9'—C8'—C12—O2156.6 (10)
C5—C4—C7—C8117.9 (3)C7—C8'—C12—C11165.9 (7)
C3—C4—C7—C862.7 (3)C9'—C8'—C12—C1142.9 (16)
C8'—C7—C8—C955.0 (17)C7—C8'—C12—C876.2 (15)
C4—C7—C8—C961.2 (5)C9'—C8'—C12—C846.8 (12)
C8'—C7—C8—C1269.6 (19)C10—C11—C13—C140.5 (4)
C4—C7—C8—C12174.1 (2)C12—C11—C13—C14177.1 (2)
C7—C8—C9—O3171.8 (2)C11—C13—C14—C150.5 (5)
C12—C8—C9—O360.6 (6)C13—C14—C15—C160.2 (5)
C8—C7—C8'—C9'48.6 (12)C14—C15—C16—C100.1 (5)
C4—C7—C8'—C9'27 (2)O3—C10—C16—C15179.7 (3)
C8—C7—C8'—C1273 (2)C11—C10—C16—C150.0 (4)
C4—C7—C8'—C12148.8 (6)C16—C10—O3—C9162.3 (3)
C7—C8'—C9'—O3174.9 (10)C11—C10—O3—C917.4 (4)
C12—C8'—C9'—O358.1 (18)C16—C10—O3—C9'160.5 (7)
O3—C10—C11—C13179.4 (2)C11—C10—O3—C9'19.8 (7)
C16—C10—C11—C130.3 (3)C8—C9—O3—C1050.6 (5)
O3—C10—C11—C122.9 (3)C8—C9—O3—C9'48.5 (9)
C16—C10—C11—C12177.4 (2)C8'—C9'—O3—C1048.9 (17)
C10—C11—C12—O2175.1 (2)C8'—C9'—O3—C948.2 (12)
C13—C11—C12—O27.3 (4)
Hydrogen-bond geometry (Å, º) top
Cg1 is the centroid of the C1–C6 ring.
D—H···AD—HH···AD···AD—H···A
O1—H1···O2i0.821.942.752 (2)173
C8—H8···O1ii0.982.393.166 (4)136
C16—H16···Cg1iii0.933.144.022 (3)159
Symmetry codes: (i) x1/2, y1/2, z+1/2; (ii) x1/2, y1/2, z1/2; (iii) x, y1, z.

Experimental details

Crystal data
Chemical formulaC16H14O3
Mr254.27
Crystal system, space groupMonoclinic, P21/n
Temperature (K)293
a, b, c (Å)5.2570 (2), 17.0254 (7), 14.6879 (5)
β (°) 97.806 (2)
V3)1302.42 (9)
Z4
Radiation typeMo Kα
µ (mm1)0.09
Crystal size (mm)0.30 × 0.20 × 0.20
Data collection
DiffractometerBruker Kappa APEX2 CCD
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 2004)
Tmin, Tmax0.962, 0.991
No. of measured, independent and
observed [I > 2σ(I)] reflections
12297, 2288, 1523
Rint0.026
(sin θ/λ)max1)0.595
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.041, 0.110, 1.11
No. of reflections2288
No. of parameters187
No. of restraints5
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.13, 0.11

Computer programs: APEX2 (Bruker, 2004), APEX2 and SAINT (Bruker, 2004), SAINT and XPREP (Bruker, 2004), SIR92 (Altomare et al., 1993), SHELXL97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 2012).

Hydrogen-bond geometry (Å, º) top
Cg1 is the centroid of the C1–C6 ring.
D—H···AD—HH···AD···AD—H···A
O1—H1···O2i0.821.942.752 (2)173
C8—H8···O1ii0.982.393.166 (4)136
C16—H16···Cg1iii0.933.144.022 (3)159
Symmetry codes: (i) x1/2, y1/2, z+1/2; (ii) x1/2, y1/2, z1/2; (iii) x, y1, z.
Acknowledgements top

SS and CRG thank the Sophisticated Analytical Instrument Facility (SAIF), Indian Institute of Technology (IIT), Chennai, for the data collection, and the Rashtriya Sikshana Samithi Trust (RSST), Sri Shivananda Memorial Rashtriya Vidyalaya (SSMRV) Degree College, for providing research facilities.

references
References top

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