supplementary materials


HTML versionpdf versioncif file3d viewstructure factorssupplementary materialsCIF check reportsimilar papers Open access

Acta Cryst. (2009). E65, o2091    [ doi:10.1107/S1600536809030244 ]

(R)-7-Bromo-2,3,4,4a-tetrahydro-1H-xanthen-1-one

A.-B. Xia, J. Tang, J.-R. Jiang, Y.-F. Wang and S.-P. Luo

Abstract top

The title compound, C13H11BrO2, contains a tricyclic ring system with one chiral center which exhibits an R configuration. The crystal structure is devoid of any classical hydrogen bonding.

Comment top

There has been growing interest in the study of domino or cascade reaction as it allows in principle the formation of multiple new bonds and stereocenters in one-pot system (Enders et al., 2007; Yu & Wang, 2002). Consequently, the title compound, (I), was synthesized as one of a series of oxa-Michael-aldol products under investigation. In this paper, the absolute configuration and crystal structure of (I) has been presented.

The title compound is shown in Fig. 1. One of the three fused rings in (I), the cyclohexanone ring (C1/C/C3/C4/C5/C13) adopts a distorted chair conformation while the ring O2/C5/C6/C11/C12/C13 is in a distorted half chair conformation. The bromophenyl ring (C6—C11/Br) is essentially planar as expected. The crystal structure is devoid of any classical hydrogen bonding. The crystal structures of closely related compound to (I) have been reported (Shi et al., 2004; Ndjakou Lenta et al., 2007).

ADDSYM in PLATON (Spek, 2009) suggested a pseudo mirror plane in the structure and P21/m as the alternate space group requiring all the atoms of the title compound to be coplanar with the atom, C2–C5 Sp2 hybridized which contravenes the true structure of the title compound.

Related literature top

For related structures, see: Shi et al. (2004); Ndjakou Lenta et al. (2007). Domino or cascade reactions allow, in principle, the formation of multiple new bonds and stereocenters in a one-pot system, see: Enders et al. (2007); Yu & Wang (2002).

Experimental top

A 1,4-dioxane (1 ml) solution of alicylic aldehyde (1 mmol) and cyclohex-2-enone (3.5 mmol) in the presence of (S)-1-methyl-2-(pyrrolidin-2-ylmethylthio)-1H-imidazole (0.3 mmol) as amine catalyst and benzoic acid (0.3 mmol) as additive was stirred at room temperature for 72 hrs. After completion of the reaction, the mixture was washed with water and extracted with ethyl acetate. The solvent was removed under reduced pressure and the residue was purified by silica gel column chromatography using petroleum ether-aether (2:1)) as an eluent. Single crystals of the title compound were obtained by slow evaporation of an acetone solution.

Refinement top

An absolute structure of (I) was determined by the Flack (1983) method without merging Friedel Pairs (1145) of reflections. H atoms were placed in calculated positions with in riding mode with C—H distances 0.93, 0.97 and 0.98 Å, for aryl, methylene and methine H-atoms; Uiso(H) = 1.2Ueq of the carrier atoms.

Computing details top

Data collection: PROCESS-AUTO (Rigaku, 2006); cell refinement: PROCESS-AUTO (Rigaku, 2006); data reduction: CrystalStructure (Rigaku/MSC and Rigaku, 2007); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997); software used to prepare material for publication: CrystalStructure (Rigaku/MSC and Rigaku, 2007) and PLATON Spek (2009).

Figures top
[Figure 1] Fig. 1. The asymmetric unit of the structure of the title compound, with the atomic labeling scheme. Displacement ellipsoids are drawn at the 40% probability level.
[Figure 2] Fig. 2. Unit cell packing of the title compound.
(R)-7-Bromo-2,3,4,4a-tetrahydro-1H-xanthen-1-one top
Crystal data top
C13H11BrO2F(000) = 280.00
Mr = 279.13Dx = 1.657 Mg m−3
Monoclinic, P21Mo Kα radiation, λ = 0.71075 Å
Hall symbol: P 2ybCell parameters from 4299 reflections
a = 7.5419 (4) Åθ = 3.2–27.4°
b = 6.9039 (3) ŵ = 3.67 mm−1
c = 10.7634 (5) ÅT = 296 K
β = 93.7110 (12)°Chunk, yellow
V = 559.26 (5) Å30.40 × 0.37 × 0.26 mm
Z = 2
Data collection top
Rigaku R-AXIS RAPID
diffractometer		1772 reflections with F2 > 2σ(F2)
Detector resolution: 10.00 pixels mm-1Rint = 0.036
ω scansθmax = 27.4°
Absorption correction: multi-scan
(ABSCOR; Higashi, 1995)		h = −9→9
Tmin = 0.252, Tmax = 0.386k = −8→8
5496 measured reflectionsl = −12→13
2525 independent reflections
Refinement top
Refinement on F2(Δ/σ)max = 0.001
R[F2 > 2σ(F2)] = 0.033Δρmax = 0.64 e Å−3
wR(F2) = 0.102Δρmin = −0.88 e Å−3
S = 1.00Extinction correction: SHELXL97 (Sheldrick, 2008)
2525 reflectionsExtinction coefficient: 0.035 (3)
147 parametersAbsolute structure: Flack (1983), 1145 Friedel pairs
H-atom parameters constrainedFlack parameter: 0.01 (2)
w = 1/[σ2(Fo2) + (0.02P)2 + P]
where P = (Fo2 + 2Fc2)/3
Crystal data top
C13H11BrO2V = 559.26 (5) Å3
Mr = 279.13Z = 2
Monoclinic, P21Mo Kα radiation
a = 7.5419 (4) ŵ = 3.67 mm−1
b = 6.9039 (3) ÅT = 296 K
c = 10.7634 (5) Å0.40 × 0.37 × 0.26 mm
β = 93.7110 (12)°
Data collection top
Rigaku R-AXIS RAPID
diffractometer		2525 independent reflections
Absorption correction: multi-scan
(ABSCOR; Higashi, 1995)		1772 reflections with F2 > 2σ(F2)
Tmin = 0.252, Tmax = 0.386Rint = 0.036
5496 measured reflectionsθmax = 27.4°
Refinement top
R[F2 > 2σ(F2)] = 0.033H-atom parameters constrained
wR(F2) = 0.102Δρmax = 0.64 e Å−3
S = 1.00Δρmin = −0.88 e Å−3
2525 reflectionsAbsolute structure: Flack (1983), 1145 Friedel pairs
147 parametersFlack parameter: 0.01 (2)
? restraints
Special details top

Experimental. The structure of the title compound was confirmed by NMR and HRMS methods: 1HNMR (500 MHz, CDCl3): 7.33–7.31(m, 3H), 6.77–6.75(d, J=9.5 Hz,1H),5.00–4.97(m, 1H),2.62–2.58 (m, 1H), 2.51–2.46(m, 1H),2.42–2.35(m, 1H),2.13–2.07(m, 1H),2.04–1.96 (m, 1H), 1.75–1.65(m, 1H) p.p.m.; 13CNMR (125 MHz, CDCl3): 197.1, 154.8, 134.4, 131.8, 131.4, 129.9, 123.9, 117.8, 114.0, 74.8, 38.8, 29.6, 17.9 p.p.m.. HRMS: (EI+) m/z calcd for (C13H11BrO2)+ 277.9942, found 277.9949.

Geometry. ENTER SPECIAL DETAILS OF THE MOLECULAR GEOMETRY

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 > 2σ(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
Br10.96613 (6)0.67049 (12)0.66752 (4)0.0633 (2)
O10.5964 (5)0.6274 (8)−0.0423 (3)0.0656 (16)
O20.2944 (3)0.6625 (11)0.3348 (2)0.0473 (7)
C10.4600 (6)0.6384 (11)0.0116 (4)0.0505 (16)
C20.2803 (7)0.6187 (12)−0.0570 (4)0.063 (2)
C30.1314 (6)0.7222 (8)0.0028 (4)0.0557 (18)
C40.1286 (5)0.6734 (16)0.1395 (3)0.0519 (11)
C50.2999 (6)0.7335 (7)0.2089 (4)0.0440 (13)
C60.4495 (4)0.6742 (14)0.4075 (3)0.0401 (8)
C70.4396 (5)0.6820 (14)0.5352 (3)0.0434 (10)
C80.5937 (5)0.6827 (14)0.6123 (3)0.0454 (11)
C90.7562 (5)0.6759 (14)0.5602 (3)0.0412 (9)
C100.7694 (5)0.6637 (16)0.4334 (3)0.0425 (9)
C110.6136 (4)0.6623 (14)0.3548 (3)0.0393 (8)
C120.6132 (5)0.6402 (11)0.2208 (4)0.0447 (15)
C130.4640 (4)0.6636 (15)0.1494 (3)0.0413 (9)
H50.30340.87530.21170.053*
H70.32940.68680.56920.052*
H80.58790.68770.69830.054*
H100.88010.65640.40040.051*
H120.71810.60950.18440.054*
H210.25090.4820−0.06220.075*
H220.28830.6705−0.14020.075*
H310.01910.6841−0.03910.067*
H320.14750.8609−0.00600.067*
H410.03040.74080.17420.062*
H420.11290.53470.14860.062*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Br10.0439 (2)0.0990 (4)0.0455 (2)−0.0020 (5)−0.00874 (17)0.0000 (5)
O10.062 (2)0.095 (5)0.0402 (16)0.016 (2)0.0060 (15)−0.009 (2)
O20.0289 (13)0.070 (2)0.0433 (14)0.006 (3)0.0015 (10)0.005 (3)
C10.053 (2)0.056 (4)0.042 (2)0.012 (3)−0.0026 (19)−0.005 (2)
C20.063 (3)0.079 (7)0.043 (2)0.004 (3)−0.015 (2)−0.003 (3)
C30.044 (2)0.073 (5)0.048 (2)0.003 (2)−0.012 (2)0.009 (2)
C40.035 (2)0.065 (3)0.056 (2)−0.011 (5)−0.0060 (17)0.009 (5)
C50.038 (2)0.054 (3)0.039 (2)0.000 (2)−0.0029 (18)0.004 (2)
C60.0311 (18)0.045 (2)0.0437 (19)−0.001 (3)0.0006 (14)0.007 (4)
C70.037 (2)0.053 (2)0.041 (2)0.000 (3)0.0100 (15)0.006 (3)
C80.047 (2)0.053 (3)0.0361 (19)−0.002 (3)0.0038 (16)−0.005 (3)
C90.0362 (19)0.047 (2)0.0400 (19)−0.003 (4)−0.0060 (14)0.005 (4)
C100.0340 (19)0.056 (2)0.0378 (18)0.001 (4)0.0050 (14)0.000 (4)
C110.0359 (19)0.044 (2)0.0376 (18)−0.002 (3)0.0014 (14)−0.005 (4)
C120.034 (2)0.058 (4)0.042 (2)0.006 (2)0.0051 (15)0.005 (3)
C130.040 (2)0.045 (2)0.0385 (19)0.001 (4)0.0004 (15)0.001 (4)
Geometric parameters (Å, °) top
Br1—C91.899 (3)C10—C111.403 (5)
O1—C11.215 (6)C11—C121.450 (5)
O2—C51.444 (5)C12—C131.330 (5)
O2—C61.367 (4)C2—H210.970
C1—C21.507 (7)C2—H220.970
C1—C131.492 (6)C3—H310.970
C2—C31.510 (8)C3—H320.970
C3—C41.511 (6)C4—H410.970
C4—C51.508 (6)C4—H420.970
C5—C131.509 (6)C5—H50.980
C6—C71.382 (5)C7—H70.930
C6—C111.397 (5)C8—H80.930
C7—C81.384 (5)C10—H100.930
C8—C91.381 (5)C12—H120.930
C9—C101.377 (5)
C5—O2—C6116.2 (3)C1—C2—H21108.1
O1—C1—C2121.5 (4)C1—C2—H22108.1
O1—C1—C13121.2 (4)C3—C2—H21108.1
C2—C1—C13117.2 (4)C3—C2—H22108.1
C1—C2—C3114.7 (4)H21—C2—H22109.5
C2—C3—C4111.5 (5)C2—C3—H31109.0
C3—C4—C5110.8 (4)C2—C3—H32109.0
O2—C5—C4107.2 (4)C4—C3—H31109.0
O2—C5—C13111.3 (4)C4—C3—H32109.0
C4—C5—C13113.7 (4)H31—C3—H32109.5
O2—C6—C7118.2 (3)C3—C4—H41109.1
O2—C6—C11120.8 (3)C3—C4—H42109.1
C7—C6—C11120.8 (3)C5—C4—H41109.1
C6—C7—C8120.0 (3)C5—C4—H42109.1
C7—C8—C9119.2 (3)H41—C4—H42109.5
Br1—C9—C8118.7 (2)O2—C5—H5108.1
Br1—C9—C10119.4 (2)C4—C5—H5108.1
C8—C9—C10121.8 (3)C13—C5—H5108.1
C9—C10—C11119.1 (3)C6—C7—H7120.0
C6—C11—C10119.0 (3)C8—C7—H7120.0
C6—C11—C12117.7 (3)C7—C8—H8120.4
C10—C11—C12123.3 (3)C9—C8—H8120.4
C11—C12—C13120.6 (4)C9—C10—H10120.4
C1—C13—C5119.6 (3)C11—C10—H10120.4
C1—C13—C12121.5 (4)C11—C12—H12119.7
C5—C13—C12118.7 (3)C13—C12—H12119.7
C5—O2—C6—C7155.2 (7)O2—C6—C7—C8176.3 (8)
C5—O2—C6—C11−30.1 (12)O2—C6—C11—C10−176.4 (9)
C6—O2—C5—C4169.6 (7)O2—C6—C11—C121.0 (13)
C6—O2—C5—C1344.7 (8)C7—C6—C11—C10−1.8 (14)
O1—C1—C2—C3−153.0 (6)C7—C6—C11—C12175.6 (8)
O1—C1—C13—C5162.5 (7)C11—C6—C7—C81.6 (14)
O1—C1—C13—C12−12.2 (13)C6—C7—C8—C90.1 (12)
C2—C1—C13—C5−20.1 (11)C7—C8—C9—Br1−178.5 (7)
C2—C1—C13—C12165.2 (8)C7—C8—C9—C10−1.6 (15)
C13—C1—C2—C329.6 (9)Br1—C9—C10—C11178.2 (7)
C1—C2—C3—C4−50.2 (8)C8—C9—C10—C111.4 (15)
C2—C3—C4—C560.7 (8)C9—C10—C11—C60.3 (11)
C3—C4—C5—O2−173.7 (6)C9—C10—C11—C12−176.9 (9)
C3—C4—C5—C13−50.2 (9)C6—C11—C12—C1311.1 (13)
O2—C5—C13—C1151.9 (7)C10—C11—C12—C13−171.7 (9)
O2—C5—C13—C12−33.3 (10)C11—C12—C13—C1−179.0 (8)
C4—C5—C13—C130.7 (10)C11—C12—C13—C56.3 (12)
C4—C5—C13—C12−154.5 (8)
references
References top

Enders, D., Grondal, C. & Huttl, M. R. M. (2007). Angew. Chem. Int. Ed. 46, 1570–1581.

Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565.

Flack, H. D. (1983). Acta Cryst. A39, 876–881.

Higashi, T. (1995). ABSCOR. Rigaku Corporation, Tokyo, Japan.

Ndjakou Lenta, B., Devkota, K. P., Neumann, B., Tsamo, E. & Sewald, N. (2007). Acta Cryst. E63, o1629–o1631.

Rigaku (2006). PROCESS-AUTO. Rigaku Corporation, Tokyo, Japan.

Rigaku/MSC and Rigaku (2007). CrystalStructure. Rigaku/MSC, The Woodlands, Texas, USA, and Rigaku Corporation, Tokyo, Japan.

Sheldrick, G. M. (2008). Acta Cryst. A64b, 112–122.

Shi, G.-F., Lu, R.-H., Yang, Y.-S., Li, C.-L., Yang, A.-M. & Cai, L.-X. (2004). Acta Cryst. E60, o878–o880.

Spek, A. L. (2009). Acta Cryst. D65, 148–155.

Yu, X. & Wang, W. (2002). Org. Biomol. Chem. 6, 2037–2046. Please check – cited as Yu et al. (2008) in text