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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 67| Part 9| September 2011| Page o2282
doi:10.1107/S160053681103100X

3,15-Dimeth­­oxy-10-methyl­tri­cyclo­[9.4.0.02,7]penta­deca-1(11),2(7),3,5,9,12,14-heptaen-8-one

Yaomin Zhu,a Jianfei Yang,b Xianfei Lib and Le Zhoub*

aSchool of Materials Science and Engineering, Henan University of Science & Technology 471022, People's Republic of China, and bCollege of Science, Northwest A&F University, Yangling 712100, People's Republic of China
*Correspondence e-mail: zhoulechem@yahoo.com.cn

(Received 6 July 2011; accepted 2 August 2011; online 11 August 2011)

The title mol­ecule, C18H16O3, contains three fused rings, of which the seven-membered cyclo­hept-2-enone ring has a screw-boat conformation. The two meth­oxy­phenyl rings make a dihedral angle of 50.4 (2)°. In the crystal, mol­ecules are linked by inter­molecular C—H⋯O hydrogen bonds, leading to a three-dimensional supra­molecular architecture.

Related literature

The title compound was obtained through an aldol condensation reaction. For general background to aldol reactions, see: Machajewski & Wong (2000[Machajewski, T. D. & Wong, C. H. (2000). Angew. Chem. Int. Ed. 39, 1352-1375.]); Nelson (1998[Nelson, S. G. (1998). Tetrahedron Asymmetry, 9, 357-389.]). For structures with C—H⋯O hydrogen bonds, see: Broder et al. (2002[Broder, C. K., Davidson, M. G., Trevor Forsyth, V., Howard, J. A. K., Lamb, S. & Mason, S. A. (2002). Cryst. Growth Des. 2, 163-169.]); Senthil Kumar et al. (2006[Senthil Kumar, V. S., Christopher Pigge, F. & Rath, N. P. (2006). Cryst. Growth Des. 6, 193-196.]).

[Scheme 1]

Experimental

Crystal data

  • C18H16O3

  • Mr = 280.31

  • Orthorhombic, P 21 21 21

  • a = 7.6615 (10) Å

  • b = 12.2005 (16) Å

  • c = 15.545 (2) Å

  • V = 1453.1 (3) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.09 mm−1

  • T = 295 K

  • 0.43 × 0.31 × 0.17 mm
Data collection

  • Bruker SMART CCD area detector diffractometer

  • Absorption correction: multi-scan (SADABS; Sheldrick, 1996[Sheldrick, G. M. (1996). SADABS. University of Göttingen, Germany.]) Tmin = 0.964, Tmax = 0.986

  • 11119 measured reflections

  • 2708 independent reflections

  • 2083 reflections with I > 2σ(I)

  • Rint = 0.034
Refinement

  • R[F2 > 2σ(F2)] = 0.037

  • wR(F2) = 0.090

  • S = 1.09

  • 2708 reflections

  • 193 parameters

  • H-atom parameters constrained

  • Δρmax = 0.10 e Å−3

  • Δρmin = −0.13 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A D⋯A D—H⋯A
C13—H13B⋯O3i 0.96 2.40 3.349 (3) 171
C10—H10⋯O1ii 0.93 2.58 3.283 (2) 133
Symmetry codes: (i) [-x+1, y-{\script{1\over 2}}, -z+{\script{3\over 2}}]; (ii) [x-{\script{1\over 2}}, -y+{\script{3\over 2}}, -z+1].

Data collection: SMART (Bruker, 2004[Bruker (2004). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2004[Bruker (2004). 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: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); software used to prepare material for publication: SHELXTL.

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S160053681103100X/zj2016sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S160053681103100X/zj2016Isup2.hkl

Supporting information file. DOI: 10.1107/S160053681103100X/zj2016Isup3.cml

checkCIF report


Comment top

Direct aldol reactions provide an atom-economical approach to create the β-hydroxy carbonyl structural unit found in many natural products and drugs (Machajewski et al. 2000; Nelson, 1998.). In our study, we were interested to the intramolecular aldol condensation reaction. To our surprise, the resulting aldol adducts are further dehydrated to afford an enone compound. The title molecule is built up from three fused rings including two phenyl rings and one seven-membered ring (Fig. 1). The non aromatic seven-membered ring has a screw boat conformation. The two methoxyphenyl rings make dihedral angles of 50.4 (2) Å. In the crystal structure, the weak intermolecular C—H···O hydrogen bonds are observed. Thus, molecules are linked to each other by intermolecular C13—H13B···O3 hydrogen bonds (C13···O3 = 3.349 (3) Å), resulting in a one-dimensional chain. The chains are further connected through the formation of intermolecular C10—H10···O1 hydrogen bonds (C10···O1 = 3.283 (2) Å), leading to a three-dimensional supmolecular architecture, as shown in Fig. 2.

Related literature top

The title compound was obtained through an aldol condensation reaction. For general background to aldol reactions, see: Machajewski & Wong (2000); Nelson (1998). For related? structures with C—H···O hydrogen bonds, see: Broder et al. (2002); Senthil Kumar et al. (2006).

Experimental top

2,2-dimethoxy-6,6-diacetyl-1,1-biphenyl (298 mm g, 1 mmol) was added to a solution of CH3CH2ONa (6.8 mg, 0.1 mmol) and enthanol (5 ml) at room temperature. The mixture was stirred, monitored by TLC. After 8 h, the mixture was extracted by ethyl acetate (3× 15 ml). The resulting solvent was removed in vacuo to yield the crude product. Purification by silica gel chromatography using 100 ~200 mesh ZCX II eluted by hexane-ethyl acetate (3:1, v/v) gave the yellow solid (196 mg, yield 70%). The crystalline compound was obtained through the slow volatilization of ethyl acetate containing the title compound.

Refinement top

All H atoms were positioned geometrically and treated as riding, with C—H bond lengths constrained to 0.93 Å (aromatic CH), 0.93 Å (methylene CH2), or 0.96 Å (methyl CH3), and with Uĩso~(H) = 1.2Ueq(C) or 1.5Ueq(methyl and methylene C).

Computing details top

Data collection: SMART (Bruker, 2004); cell refinement: SAINT (Bruker, 2004); data reduction: SAINT (Bruker, 2004); 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. View of the title molecular structure with atom numbering scheme and 50% probability displacement ellipsoids for non-hydrogen atoms.
[Figure 2] Fig. 2. View of three-dimensional structure (C—H···O hydrogen bonds are represented as dashed lines).
3,15-Dimethoxy-10-methyltricyclo[9.4.0.02,7]pentadeca- 1(11),2(7),3,5,9,12,14-heptaen-8-one top
Crystal data top
C18H16O3F(000) = 592
Mr = 280.31Dx = 1.281 Mg m−3
Orthorhombic, P212121Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ac 2abCell parameters from 2351 reflections
a = 7.6615 (10) Åθ = 2.6–22.6°
b = 12.2005 (16) ŵ = 0.09 mm−1
c = 15.545 (2) ÅT = 295 K
V = 1453.1 (3) Å3Block, yellow
Z = 40.43 × 0.31 × 0.17 mm
Data collection top
Bruker SMART CCD area detector
diffractometer		2708 independent reflections
Radiation source: fine-focus sealed tube2083 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.034
ϕ and ω scansθmax = 25.5°, θmin = 2.6°
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)		h = −9→9
Tmin = 0.964, Tmax = 0.986k = −14→14
11119 measured reflectionsl = −18→18
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)] = 0.037Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.090H-atom parameters constrained
S = 1.09 w = 1/[σ2(Fo2) + (0.0385P)2 + 0.0759P]
where P = (Fo2 + 2Fc2)/3
2708 reflections(Δ/σ)max < 0.001
193 parametersΔρmax = 0.10 e Å−3
0 restraintsΔρmin = −0.13 e Å−3
Crystal data top
C18H16O3V = 1453.1 (3) Å3
Mr = 280.31Z = 4
Orthorhombic, P212121Mo Kα radiation
a = 7.6615 (10) ŵ = 0.09 mm−1
b = 12.2005 (16) ÅT = 295 K
c = 15.545 (2) Å0.43 × 0.31 × 0.17 mm
Data collection top
Bruker SMART CCD area detector
diffractometer		2708 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)		2083 reflections with I > 2σ(I)
Tmin = 0.964, Tmax = 0.986Rint = 0.034
11119 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0370 restraints
wR(F2) = 0.090H-atom parameters constrained
S = 1.09Δρmax = 0.10 e Å−3
2708 reflectionsΔρmin = −0.13 e Å−3
193 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
O10.90746 (18)0.51793 (11)0.45436 (10)0.0617 (4)
O20.6310 (2)0.46929 (11)0.35471 (8)0.0590 (4)
O30.4247 (3)0.68747 (15)0.67899 (12)0.0975 (6)
C10.8412 (3)0.43948 (14)0.50732 (12)0.0435 (5)
C20.6641 (2)0.45458 (13)0.53147 (11)0.0391 (4)
C30.5949 (3)0.38457 (15)0.59460 (11)0.0423 (5)
C40.6961 (3)0.29640 (16)0.62432 (12)0.0506 (5)
H40.64900.24830.66450.061*
C50.8624 (3)0.27996 (16)0.59543 (14)0.0544 (5)
H50.92560.21960.61470.065*
C60.9376 (3)0.35217 (15)0.53789 (14)0.0516 (5)
H61.05220.34210.51990.062*
C70.5694 (3)0.55704 (15)0.39995 (13)0.0478 (5)
C80.5662 (2)0.54490 (14)0.48981 (12)0.0415 (4)
C90.4791 (3)0.62605 (15)0.53714 (14)0.0502 (5)
C100.4157 (3)0.72015 (16)0.49742 (18)0.0658 (6)
H100.36070.77400.53000.079*
C110.4340 (3)0.73350 (19)0.41045 (19)0.0756 (7)
H110.39660.79800.38440.091*
C120.5077 (3)0.65175 (18)0.36140 (17)0.0657 (6)
H120.51600.66020.30210.079*
C130.3278 (3)0.3040 (2)0.66884 (15)0.0734 (7)
H13A0.21270.32510.68670.110*
H13B0.38990.27360.71690.110*
H13C0.31950.25010.62400.110*
C140.4239 (3)0.40290 (18)0.63578 (12)0.0519 (5)
C150.3608 (3)0.5025 (2)0.65305 (13)0.0634 (6)
H150.25790.50400.68480.076*
C160.4316 (3)0.6103 (2)0.62877 (14)0.0624 (6)
C171.0812 (3)0.5087 (2)0.42411 (17)0.0778 (7)
H17A1.09260.44310.39040.117*
H17B1.15960.50540.47220.117*
H17C1.10910.57120.38930.117*
C180.6894 (4)0.4865 (3)0.26972 (15)0.0946 (10)
H18A0.77020.54660.26870.142*
H18B0.59140.50320.23350.142*
H18C0.74620.42150.24910.142*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0433 (8)0.0547 (8)0.0872 (10)−0.0025 (7)0.0133 (8)0.0130 (8)
O20.0767 (10)0.0580 (8)0.0422 (8)0.0003 (8)0.0094 (7)0.0039 (7)
O30.1176 (15)0.0921 (12)0.0829 (12)0.0259 (12)−0.0124 (11)−0.0455 (11)
C10.0437 (12)0.0397 (9)0.0472 (11)−0.0009 (9)0.0022 (9)−0.0023 (8)
C20.0390 (10)0.0380 (9)0.0403 (10)−0.0017 (8)−0.0028 (8)−0.0037 (8)
C30.0445 (11)0.0457 (10)0.0367 (9)−0.0050 (9)−0.0059 (9)−0.0040 (8)
C40.0575 (14)0.0501 (11)0.0442 (12)−0.0052 (10)−0.0081 (10)0.0055 (9)
C50.0585 (14)0.0481 (11)0.0566 (12)0.0082 (10)−0.0117 (11)0.0036 (10)
C60.0429 (12)0.0533 (11)0.0586 (13)0.0059 (10)−0.0017 (11)−0.0056 (10)
C70.0465 (12)0.0436 (10)0.0533 (12)−0.0009 (10)−0.0003 (10)0.0048 (9)
C80.0371 (10)0.0393 (9)0.0481 (11)−0.0021 (8)−0.0021 (9)−0.0003 (8)
C90.0426 (12)0.0455 (10)0.0626 (14)0.0007 (9)−0.0098 (10)−0.0103 (10)
C100.0577 (14)0.0449 (12)0.0949 (19)0.0099 (11)−0.0053 (13)−0.0067 (12)
C110.0739 (18)0.0526 (13)0.100 (2)0.0139 (13)−0.0096 (16)0.0202 (14)
C120.0654 (15)0.0643 (14)0.0673 (16)0.0037 (12)−0.0007 (13)0.0209 (13)
C130.0571 (15)0.0989 (18)0.0641 (15)−0.0115 (14)0.0047 (12)0.0218 (14)
C140.0446 (12)0.0717 (14)0.0392 (11)0.0011 (11)−0.0005 (10)−0.0001 (10)
C150.0490 (13)0.0945 (18)0.0467 (12)0.0074 (13)0.0045 (11)−0.0071 (12)
C160.0564 (14)0.0690 (14)0.0616 (14)0.0134 (12)−0.0114 (12)−0.0210 (12)
C170.0504 (14)0.0781 (16)0.105 (2)−0.0057 (13)0.0223 (14)0.0109 (15)
C180.126 (3)0.108 (2)0.0490 (13)0.030 (2)0.0240 (15)0.0192 (14)
Geometric parameters (Å, º) top
O1—C11.361 (2)C9—C161.483 (3)
O1—C171.416 (2)C10—C111.369 (3)
O2—C71.365 (2)C10—H100.9300
O2—C181.411 (3)C11—C121.376 (3)
O3—C161.225 (2)C11—H110.9300
C1—C61.381 (3)C12—H120.9300
C1—C21.419 (3)C13—C141.504 (3)
C2—C31.405 (2)C13—H13A0.9600
C2—C81.482 (2)C13—H13B0.9600
C3—C41.404 (3)C13—H13C0.9600
C3—C141.475 (3)C14—C151.335 (3)
C4—C51.366 (3)C15—C161.472 (3)
C4—H40.9300C15—H150.9300
C5—C61.381 (3)C17—H17A0.9600
C5—H50.9300C17—H17B0.9600
C6—H60.9300C17—H17C0.9600
C7—C121.385 (3)C18—H18A0.9600
C7—C81.405 (3)C18—H18B0.9600
C8—C91.402 (3)C18—H18C0.9600
C9—C101.391 (3)
C1—O1—C17119.71 (17)C10—C11—H11119.9
C7—O2—C18118.37 (17)C12—C11—H11119.9
O1—C1—C6123.45 (19)C11—C12—C7120.3 (2)
O1—C1—C2115.18 (16)C11—C12—H12119.8
C6—C1—C2121.35 (18)C7—C12—H12119.8
C3—C2—C1117.83 (16)C14—C13—H13A109.5
C3—C2—C8124.46 (17)C14—C13—H13B109.5
C1—C2—C8117.70 (16)H13A—C13—H13B109.5
C4—C3—C2119.13 (18)C14—C13—H13C109.5
C4—C3—C14117.64 (18)H13A—C13—H13C109.5
C2—C3—C14123.12 (17)H13B—C13—H13C109.5
C5—C4—C3121.30 (19)C15—C14—C3123.2 (2)
C5—C4—H4119.3C15—C14—C13118.9 (2)
C3—C4—H4119.3C3—C14—C13117.48 (19)
C4—C5—C6120.54 (19)C14—C15—C16128.9 (2)
C4—C5—H5119.7C14—C15—H15115.6
C6—C5—H5119.7C16—C15—H15115.6
C1—C6—C5119.47 (19)O3—C16—C15120.5 (2)
C1—C6—H6120.3O3—C16—C9121.5 (2)
C5—C6—H6120.3C15—C16—C9116.94 (18)
O2—C7—C12123.33 (19)O1—C17—H17A109.5
O2—C7—C8115.82 (16)O1—C17—H17B109.5
C12—C7—C8120.8 (2)H17A—C17—H17B109.5
C9—C8—C7117.10 (17)O1—C17—H17C109.5
C9—C8—C2122.44 (17)H17A—C17—H17C109.5
C7—C8—C2120.26 (17)H17B—C17—H17C109.5
C10—C9—C8121.1 (2)O2—C18—H18A109.5
C10—C9—C16116.6 (2)O2—C18—H18B109.5
C8—C9—C16121.94 (18)H18A—C18—H18B109.5
C11—C10—C9120.0 (2)O2—C18—H18C109.5
C11—C10—H10120.0H18A—C18—H18C109.5
C9—C10—H10120.0H18B—C18—H18C109.5
C10—C11—C12120.2 (2)
C17—O1—C1—C63.6 (3)C3—C2—C8—C7−132.37 (19)
C17—O1—C1—C2−177.90 (18)C1—C2—C8—C749.1 (2)
O1—C1—C2—C3−171.97 (16)C7—C8—C9—C10−6.8 (3)
C6—C1—C2—C36.6 (3)C2—C8—C9—C10168.16 (18)
O1—C1—C2—C86.6 (2)C7—C8—C9—C16165.73 (19)
C6—C1—C2—C8−174.83 (16)C2—C8—C9—C16−19.3 (3)
C1—C2—C3—C4−6.6 (2)C8—C9—C10—C111.6 (3)
C8—C2—C3—C4174.93 (17)C16—C9—C10—C11−171.3 (2)
C1—C2—C3—C14169.41 (17)C9—C10—C11—C123.1 (4)
C8—C2—C3—C14−9.1 (3)C10—C11—C12—C7−2.3 (4)
C2—C3—C4—C52.5 (3)O2—C7—C12—C11174.6 (2)
C14—C3—C4—C5−173.75 (18)C8—C7—C12—C11−3.2 (3)
C3—C4—C5—C62.1 (3)C4—C3—C14—C15141.1 (2)
O1—C1—C6—C5176.20 (18)C2—C3—C14—C15−34.9 (3)
C2—C1—C6—C5−2.2 (3)C4—C3—C14—C13−31.5 (2)
C4—C5—C6—C1−2.2 (3)C2—C3—C14—C13152.51 (19)
C18—O2—C7—C1221.8 (3)C3—C14—C15—C166.9 (3)
C18—O2—C7—C8−160.3 (2)C13—C14—C15—C16179.3 (2)
O2—C7—C8—C9−170.39 (17)C14—C15—C16—O3−141.6 (2)
C12—C7—C8—C97.6 (3)C14—C15—C16—C949.7 (3)
O2—C7—C8—C214.6 (3)C10—C9—C16—O3−37.9 (3)
C12—C7—C8—C2−167.46 (18)C8—C9—C16—O3149.3 (2)
C3—C2—C8—C952.8 (3)C10—C9—C16—C15130.6 (2)
C1—C2—C8—C9−125.65 (19)C8—C9—C16—C15−42.2 (3)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C13—H13B···O3i0.962.403.349 (3)171
C10—H10···O1ii0.932.583.283 (2)133
Symmetry codes: (i) −x+1, y−1/2, −z+3/2; (ii) x−1/2, −y+3/2, −z+1.

Experimental details

Crystal data
Chemical formulaC18H16O3
Mr280.31
Crystal system, space groupOrthorhombic, P212121
Temperature (K)295
a, b, c (Å)7.6615 (10), 12.2005 (16), 15.545 (2)
V (Å3)1453.1 (3)
Z4
Radiation typeMo Kα
µ (mm−1)0.09
Crystal size (mm)0.43 × 0.31 × 0.17
Data collection
DiffractometerBruker SMART CCD area detector
diffractometer
Absorption correctionMulti-scan
(SADABS; Sheldrick, 1996)
Tmin, Tmax0.964, 0.986
No. of measured, independent and
observed [I > 2σ(I)] reflections		11119, 2708, 2083
Rint0.034
(sin θ/λ)max (Å−1)0.606
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.037, 0.090, 1.09
No. of reflections2708
No. of parameters193
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å−3)0.10, −0.13

Computer programs: SMART (Bruker, 2004), SAINT (Bruker, 2004), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C13—H13B···O3i0.962.403.349 (3)171.3
C10—H10···O1ii0.932.583.283 (2)133.2
Symmetry codes: (i) −x+1, y−1/2, −z+3/2; (ii) x−1/2, −y+3/2, −z+1.
 

Acknowledgements

We are grateful to the National Natural Sciences Foundation of China (grant No. 20872057) and the Natural Science Foundation of Henan Province (No. 082300420040) for financial support.

References

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This is an open-access article distributed under the terms of the Creative Commons Attribution (CC-BY) Licence, which permits unrestricted use, distribution, and reproduction in any medium, provided the original authors and source are cited.

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ISSN: 2056-9890
Volume 67| Part 9| September 2011| Page o2282
doi:10.1107/S160053681103100X
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