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

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890

rac-7-Methyl-3-[(7-methyl-4-oxo­chro­man-3-yl)meth­yl]-4H-chromen-4-one

aDepartment of Chemistry, Annamalai University, Annamalai Nagar, Chidambaram, India, and bShasun Reaearch Centre, 27 Vandaloor Kelambakkam Road, Keezhakottaiyur, Meelakottaiyur Post, Chennai, India
*Correspondence e-mail: soma78@gmail.com

(Received 6 March 2013; accepted 7 April 2013; online 20 April 2013)

In the racemic title compound, C21H18O4, the chromone ring is essentially planar [maximum deviation from the least-squares plane = 0.026 (3) Å], with a dihedral angle of 78.18 (12)° between the benzene rings of the chromanone and chromenone moieties. In the crystal, there are weak ππ stacking inter­actions [minimum ring centroid separation = 3.9286 (17) Å].

Related literature

For backgound to bis-chromanones, see: Dean & Murray (1975[Dean, F. M. & Murray, S. (1975). J. Chem. Soc. Perkin Trans. 1, pp. 1706-1711.]); Santhosh & Balasubramanian (1991[Santhosh, K. C. & Balasubramanian, K. K. (1991). Tetrahedron Lett. 32, 7727-7730.]); Panja et al. (2009[Panja, S. K., Maiti, S., Drew, M. G. B. & Bandyopadhyay, Ch. (2009). Tetrahedron, 65, 1276-1280.]). For related structures, see: Ambartsumyan et al. (2012[Ambartsumyan, A. A., Vasiléva, T. T., Chakhovskaya, O. V., Mysova, N. E., Tuskaev, V. A., Khrustalev, V. N. & Kochetkov, K. A. (2012). Russ. J. Org. Chem. 48, 451-455.]); Nyburg et al. (1986[Nyburg, S. C., Prasad, L., Leong, T. S. & Still, I. W. J. (1986). Acta Cryst. C42, 816-821.]); Li et al. (2010[Li, Y., Xiao, T., Liu, D. & Yu, G. (2010). Acta Cryst. E66, o694.]).

[Scheme 1]

Experimental

Crystal data
  • C21H18O4

  • Mr = 334.35

  • Monoclinic, P 21 /n

  • a = 10.664 (2) Å

  • b = 6.6428 (13) Å

  • c = 23.754 (5) Å

  • β = 91.11 (3)°

  • V = 1682.4 (6) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.09 mm−1

  • T = 293 K

  • 0.44 × 0.22 × 0.22 mm

Data collection
  • Bruker SMART CCD diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2007[Bruker (2007). SMART, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.961, Tmax = 0.980

  • 11780 measured reflections

  • 4032 independent reflections

  • 1982 reflections with I > 2σ(I)

  • Rint = 0.029

Refinement
  • R[F2 > 2σ(F2)] = 0.059

  • wR(F2) = 0.180

  • S = 1.02

  • 4032 reflections

  • 229 parameters

  • H-atom parameters constrained

  • Δρmax = 0.43 e Å−3

  • Δρmin = −0.30 e Å−3

Data collection: SMART (Bruker, 2007[Bruker (2007). SMART, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2007[Bruker (2007). 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


Comment top

The chromanone moiety forms an important component in pharmacophores in a number of biologically active molecules of synthetic as well as natural origin. Bis-chromanones bridged by a methylene group at C3 of the ring are considered to be a biologically important class of molecules (Santhosh & Balasubramanian, 1991; Panja, et al., 2009). Herein we report the structure of the racemic title compound, C21H18O4, in which the dihedral angle between the phenyl rings of the two chromanone moieties is 78.18 (12)° (Fig. 1). The chromone ring is essentially planar [maximum deviation from the l.s. plane = 0.026 (3) Å (C15)], while in the chromanone ring the maximum deviation is 0.206 (4) Å (C19)]. In the chromanone ring system, the C19—C20 bond length is short [1.380 (5)]. The torsion angles about the central methylene carbon C12 (C15—C1—C12—C20 and C19—C20—C12—C1) are -93.91 (3) and -37.48 (4)°, respectively. The angle subtended at C12 by the C—C bonds (C1—C12—C20) is 114.87 (2)°. The olefinic bond length [C1—C15 = 1.324 (4) Å] is close to the values found in known chromanone systems (Ambartsumyan et al., 2012). Some examples of bis-chromanone structures are known (Dean & Murray, 1975). In the crystal, there are weak π···π stacking interactions [minimum ring centroid separation = 3.9286 (17) Å].

Related literature top

For backgound to bis-chromanones, see: Dean & Murray (1975); Santhosh & Balasubramanian (1991); Panja et al. (2009). For related structures, see: Ambartsumyan et al. (2012); Nyburg et al. (1986); Li et al. (2010).

Experimental top

In a dry single-neck round-bottom flask, 4-chloro-3-formyl chromene (1 mol) and sodium acetate (1.1 mol) was taken, and DMF (5 vol) was added. The reaction mixture was stirred at 70 – 80 °C for 7–8 h. The progress of the reaction was monitored by TLC. After completion of the reaction, the mixture was cooled to room temperature and then quenched with water, extracted with ethyl acetate and concentrated under reduced pressure, giving the crude bis-chromanone product. This product was purified on silica gel using ethyl acetate–hexane solvent, giving the pure title compound.

Computing details top

Data collection: SMART (Bruker, 2007); cell refinement: SAINT (Bruker, 2007); data reduction: SAINT (Bruker, 2007); 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. The molecular conformation and atom numbering scheme for the title compound, showing 50% probability displacement ellipsoids.
rac-7-Methyl-3-[(7-methyl-4-oxochroman-3-yl)methyl]-4H-chromen-4-one top
Crystal data top
C21H18O4F(000) = 704
Mr = 334.35Dx = 1.320 Mg m3
Monoclinic, P21/nMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ynCell parameters from 2970 reflections
a = 10.664 (2) Åθ = 2.5–28.2°
b = 6.6428 (13) ŵ = 0.09 mm1
c = 23.754 (5) ÅT = 293 K
β = 91.11 (3)°Crystal, yellow
V = 1682.4 (6) Å30.44 × 0.22 × 0.22 mm
Z = 4
Data collection top
Bruker SMART CCD
diffractometer
4032 independent reflections
Radiation source: fine-focus sealed tube1982 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.029
ϕ and ω scansθmax = 28.3°, θmin = 3.2°
Absorption correction: multi-scan
(SADABS; Bruker, 2007)
h = 1312
Tmin = 0.961, Tmax = 0.980k = 88
11780 measured reflectionsl = 2931
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)] = 0.059Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.180H-atom parameters constrained
S = 1.02 w = 1/[σ2(Fo2) + (0.0748P)2 + 0.4282P]
where P = (Fo2 + 2Fc2)/3
4032 reflections(Δ/σ)max < 0.001
229 parametersΔρmax = 0.43 e Å3
0 restraintsΔρmin = 0.30 e Å3
Crystal data top
C21H18O4V = 1682.4 (6) Å3
Mr = 334.35Z = 4
Monoclinic, P21/nMo Kα radiation
a = 10.664 (2) ŵ = 0.09 mm1
b = 6.6428 (13) ÅT = 293 K
c = 23.754 (5) Å0.44 × 0.22 × 0.22 mm
β = 91.11 (3)°
Data collection top
Bruker SMART CCD
diffractometer
4032 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2007)
1982 reflections with I > 2σ(I)
Tmin = 0.961, Tmax = 0.980Rint = 0.029
11780 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0590 restraints
wR(F2) = 0.180H-atom parameters constrained
S = 1.02Δρmax = 0.43 e Å3
4032 reflectionsΔρmin = 0.30 e Å3
229 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
O20.12544 (16)0.0887 (3)0.10824 (8)0.0673 (5)
O10.34094 (18)0.1176 (2)0.01163 (8)0.0682 (5)
C10.0420 (2)0.1514 (3)0.10862 (11)0.0573 (7)
C20.3259 (2)0.4731 (3)0.03163 (10)0.0472 (6)
O40.18080 (18)0.6629 (2)0.01958 (8)0.0729 (6)
C30.0456 (2)0.1335 (3)0.17464 (9)0.0471 (6)
C40.2280 (2)0.4997 (3)0.00924 (10)0.0537 (6)
C50.1317 (2)0.3631 (3)0.16993 (11)0.0566 (7)
H50.20750.40030.15290.068*
C60.0679 (2)0.1937 (3)0.15148 (10)0.0493 (6)
C70.3769 (2)0.2828 (3)0.04092 (10)0.0533 (6)
C80.0330 (3)0.4157 (4)0.23729 (12)0.0684 (8)
H80.06760.49090.26670.082*
O30.2109 (2)0.1038 (3)0.17275 (9)0.0836 (6)
C90.1091 (2)0.0457 (4)0.15384 (10)0.0550 (6)
C100.0960 (2)0.2503 (4)0.21857 (10)0.0604 (7)
H100.17260.21520.23510.072*
C110.4571 (3)0.6020 (4)0.10497 (12)0.0634 (7)
H110.48260.71000.12690.076*
C120.0952 (3)0.3414 (3)0.08411 (11)0.0606 (7)
H12A0.02630.42520.07080.073*
H12B0.13910.41450.11390.073*
C130.3700 (2)0.6324 (3)0.06455 (11)0.0581 (7)
H130.33920.76150.05870.070*
C140.5085 (2)0.4123 (4)0.11405 (11)0.0631 (7)
C150.0676 (3)0.0812 (4)0.09029 (12)0.0684 (8)
H150.10900.15530.06240.082*
C160.0817 (3)0.4749 (4)0.21350 (11)0.0605 (7)
C170.4669 (3)0.2547 (4)0.08142 (12)0.0652 (7)
H170.50010.12680.08680.078*
C180.6082 (3)0.3821 (5)0.15727 (14)0.0897 (10)
H18A0.56980.37520.19410.135*
H18B0.65250.25910.14950.135*
H18C0.66600.49300.15580.135*
C190.2677 (4)0.1520 (4)0.03518 (17)0.0991 (12)
H190.22050.02970.04180.119*
H10.32470.16870.06720.62 (11)*
C200.1836 (3)0.3097 (4)0.03647 (15)0.0846 (10)
H200.12360.26400.00740.102*
C210.1514 (3)0.6556 (5)0.23528 (16)0.0968 (11)
H21A0.17300.63330.27380.145*
H21B0.09900.77270.23280.145*
H21C0.22640.67580.21300.145*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O20.0557 (11)0.0714 (11)0.0742 (12)0.0134 (9)0.0163 (10)0.0252 (10)
O10.0876 (14)0.0363 (8)0.0811 (13)0.0084 (8)0.0148 (11)0.0026 (8)
C10.0505 (16)0.0538 (13)0.0673 (17)0.0022 (12)0.0023 (13)0.0107 (12)
C20.0488 (14)0.0389 (11)0.0536 (14)0.0033 (10)0.0045 (12)0.0018 (10)
O40.0857 (14)0.0385 (9)0.0954 (14)0.0122 (9)0.0249 (11)0.0127 (9)
C30.0463 (14)0.0516 (12)0.0434 (13)0.0032 (10)0.0013 (11)0.0001 (10)
C40.0595 (16)0.0373 (11)0.0643 (16)0.0021 (11)0.0007 (13)0.0061 (11)
C50.0528 (15)0.0562 (14)0.0610 (16)0.0059 (12)0.0092 (13)0.0018 (12)
C60.0500 (15)0.0513 (12)0.0466 (13)0.0053 (11)0.0026 (12)0.0044 (11)
C70.0597 (16)0.0413 (12)0.0587 (15)0.0011 (11)0.0027 (13)0.0043 (11)
C80.0706 (19)0.0727 (17)0.0621 (17)0.0132 (15)0.0064 (15)0.0242 (14)
O30.0722 (14)0.0901 (14)0.0873 (14)0.0270 (11)0.0280 (12)0.0159 (11)
C90.0530 (16)0.0582 (14)0.0536 (15)0.0038 (12)0.0053 (13)0.0008 (12)
C100.0554 (16)0.0719 (16)0.0537 (15)0.0039 (13)0.0019 (13)0.0093 (13)
C110.0646 (18)0.0589 (15)0.0666 (17)0.0138 (13)0.0011 (15)0.0009 (13)
C120.0640 (17)0.0497 (13)0.0683 (17)0.0035 (12)0.0051 (14)0.0063 (12)
C130.0581 (16)0.0439 (12)0.0723 (17)0.0029 (11)0.0012 (14)0.0009 (12)
C140.0568 (17)0.0703 (17)0.0622 (17)0.0111 (13)0.0008 (14)0.0147 (14)
C150.0621 (18)0.0651 (16)0.0775 (19)0.0048 (14)0.0101 (15)0.0263 (14)
C160.0658 (18)0.0550 (14)0.0615 (16)0.0045 (13)0.0187 (14)0.0104 (12)
C170.0693 (18)0.0516 (14)0.0746 (18)0.0030 (13)0.0015 (15)0.0140 (13)
C180.084 (2)0.099 (2)0.087 (2)0.0138 (18)0.0216 (19)0.0229 (18)
C190.133 (3)0.0430 (14)0.124 (3)0.0074 (17)0.060 (3)0.0136 (16)
C200.105 (2)0.0431 (14)0.107 (2)0.0176 (14)0.041 (2)0.0204 (14)
C210.102 (3)0.078 (2)0.111 (3)0.0075 (18)0.027 (2)0.0322 (19)
Geometric parameters (Å, º) top
O2—C151.359 (3)C10—H100.9300
O2—C61.376 (3)C11—C131.364 (4)
O1—C71.359 (3)C11—C141.393 (3)
O1—C191.390 (3)C11—H110.9300
C1—C151.324 (3)C12—C201.501 (4)
C1—C91.459 (4)C12—H12A0.9700
C1—C121.505 (3)C12—H12B0.9700
C2—C71.395 (3)C13—H130.9300
C2—C131.402 (3)C14—C171.381 (4)
C2—C41.451 (3)C14—C181.505 (4)
O4—C41.222 (3)C15—H150.9300
C3—C61.379 (3)C16—C211.508 (4)
C3—C101.399 (3)C17—H170.9300
C3—C91.460 (3)C18—H18A0.9600
C4—C201.499 (3)C18—H18B0.9600
C5—C161.373 (4)C18—H18C0.9600
C5—C61.390 (3)C19—C201.380 (4)
C5—H50.9300C19—H190.9700
C7—C171.385 (3)C19—H10.9700
C8—C101.367 (4)C20—H200.9800
C8—C161.394 (4)C21—H21A0.9600
C8—H80.9300C21—H21B0.9600
O3—C91.229 (3)C21—H21C0.9600
C15—O2—C6117.2 (2)H12A—C12—H12B107.5
C7—O1—C19116.44 (18)C11—C13—C2121.4 (2)
C15—C1—C9119.3 (2)C11—C13—H13119.3
C15—C1—C12120.3 (2)C2—C13—H13119.3
C9—C1—C12120.3 (2)C17—C14—C11117.9 (2)
C7—C2—C13117.4 (2)C17—C14—C18121.4 (3)
C7—C2—C4120.3 (2)C11—C14—C18120.8 (3)
C13—C2—C4122.3 (2)C1—C15—O2126.3 (2)
C6—C3—C10117.3 (2)C1—C15—H15116.8
C6—C3—C9120.7 (2)O2—C15—H15116.8
C10—C3—C9122.1 (2)C5—C16—C8118.5 (2)
O4—C4—C2123.2 (2)C5—C16—C21120.2 (3)
O4—C4—C20121.7 (2)C8—C16—C21121.3 (3)
C2—C4—C20115.07 (19)C14—C17—C7121.5 (2)
C16—C5—C6119.4 (3)C14—C17—H17119.3
C16—C5—H5120.3C7—C17—H17119.3
C6—C5—H5120.3C14—C18—H18A109.5
O2—C6—C3121.8 (2)C14—C18—H18B109.5
O2—C6—C5115.6 (2)H18A—C18—H18B109.5
C3—C6—C5122.7 (2)C14—C18—H18C109.5
O1—C7—C17116.9 (2)H18A—C18—H18C109.5
O1—C7—C2122.4 (2)H18B—C18—H18C109.5
C17—C7—C2120.6 (2)C20—C19—O1121.2 (3)
C10—C8—C16121.9 (2)C20—C19—H19107.0
C10—C8—H8119.1O1—C19—H19107.0
C16—C8—H8119.1C20—C19—H1107.0
O3—C9—C1122.3 (2)O1—C19—H1107.0
O3—C9—C3123.0 (2)H19—C19—H1106.8
C1—C9—C3114.7 (2)C19—C20—C4114.7 (2)
C8—C10—C3120.3 (3)C19—C20—C12122.7 (3)
C8—C10—H10119.8C4—C20—C12114.6 (2)
C3—C10—H10119.8C19—C20—H2099.5
C13—C11—C14121.2 (2)C4—C20—H2099.5
C13—C11—H11119.4C12—C20—H2099.5
C14—C11—H11119.4C16—C21—H21A109.5
C20—C12—C1114.9 (2)C16—C21—H21B109.5
C20—C12—H12A108.5H21A—C21—H21B109.5
C1—C12—H12A108.5C16—C21—H21C109.5
C20—C12—H12B108.5H21A—C21—H21C109.5
C1—C12—H12B108.5H21B—C21—H21C109.5
C19—O1—C7—C211.4 (4)C6—C3—C9—O3179.2 (2)
C19—O1—C7—C17169.2 (3)C6—C3—C9—C10.9 (3)
C7—O1—C19—C2033.0 (4)C10—C3—C9—O31.1 (4)
C15—O2—C6—C32.0 (3)C10—C3—C9—C1178.9 (2)
C15—O2—C6—C5178.0 (2)C6—C3—C10—C80.5 (4)
C6—O2—C15—C13.3 (4)C9—C3—C10—C8179.2 (2)
C12—C1—C9—O31.4 (4)O4—C4—C20—C1210.6 (4)
C12—C1—C9—C3178.6 (2)O4—C4—C20—C19160.5 (3)
C15—C1—C9—O3179.8 (3)C2—C4—C20—C12172.1 (2)
C15—C1—C9—C30.2 (3)C2—C4—C20—C1922.2 (4)
C9—C1—C12—C2087.7 (3)C16—C5—C6—O2179.1 (2)
C15—C1—C12—C2093.9 (3)C16—C5—C6—C31.0 (4)
C9—C1—C15—O22.4 (4)C6—C5—C16—C80.9 (4)
C12—C1—C15—O2179.3 (2)C6—C5—C16—C21178.2 (2)
C7—C2—C4—O4179.2 (2)O1—C7—C17—C14179.0 (3)
C7—C2—C4—C203.6 (3)C2—C7—C17—C140.4 (4)
C13—C2—C4—O43.1 (4)C16—C8—C10—C30.5 (4)
C13—C2—C4—C20174.2 (2)C10—C8—C16—C50.2 (4)
C4—C2—C7—O12.0 (3)C10—C8—C16—C21178.9 (3)
C4—C2—C7—C17177.5 (2)C14—C11—C13—C21.9 (4)
C13—C2—C7—O1179.8 (2)C13—C11—C14—C171.1 (4)
C13—C2—C7—C170.4 (3)C13—C11—C14—C18177.6 (3)
C4—C2—C13—C11176.3 (2)C1—C12—C20—C4175.3 (2)
C7—C2—C13—C111.5 (4)C1—C12—C20—C1937.5 (4)
C9—C3—C6—O20.1 (3)C11—C14—C17—C70.1 (4)
C9—C3—C6—C5180.0 (2)C18—C14—C17—C7178.8 (3)
C10—C3—C6—O2179.8 (2)O1—C19—C20—C438.2 (5)
C10—C3—C6—C50.2 (3)O1—C19—C20—C12174.7 (3)

Experimental details

Crystal data
Chemical formulaC21H18O4
Mr334.35
Crystal system, space groupMonoclinic, P21/n
Temperature (K)293
a, b, c (Å)10.664 (2), 6.6428 (13), 23.754 (5)
β (°) 91.11 (3)
V3)1682.4 (6)
Z4
Radiation typeMo Kα
µ (mm1)0.09
Crystal size (mm)0.44 × 0.22 × 0.22
Data collection
DiffractometerBruker SMART CCD
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 2007)
Tmin, Tmax0.961, 0.980
No. of measured, independent and
observed [I > 2σ(I)] reflections
11780, 4032, 1982
Rint0.029
(sin θ/λ)max1)0.667
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.059, 0.180, 1.02
No. of reflections4032
No. of parameters229
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.43, 0.30

Computer programs: SMART (Bruker, 2007), SAINT (Bruker, 2007), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

 

Acknowledgements

The authors are thankful to the University Grants Commission, New Delhi, India, for financial support in the form of a Major Research Project. In addition, they express thanks to Dr Srinivasulu and Dr Jai Anand Garg for their valuable support in the preparation of this structure report.

References

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