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Acta Crystallogr Sect E Struct Rep Online. 2009 May 1; 65(Pt 5): o1151.
Published online 2009 April 30. doi:  10.1107/S1600536809014251
PMCID: PMC2977817

7,14-Bis(4-bromo­phen­yl)-2,11,11-trimethyl-1,4,10,12-tetra­oxa­dispiro­[4.2.5.2]penta­decane-9,13-dione

Abstract

In the mol­ecule of the title compound, C26H26Br2O6, the cyclo­hexane ring is in a chair conformation, while the five-membered and 1,3-dioxane rings both adopt envelope conformations. The dihedral angle between the benzene rings is 77.21 (3)°. In the crystal structure, weak inter­molecular C—H(...)O inter­actions link the mol­ecules into centrosymmetric dimers, forming R 2 2(14) ring motifs. One of the Br atoms, the methyl C and H atoms, and the C atom bonded to the methyl group of the five-membered ring are disordered over two positions. The Br atoms were refined with occupancies of 0.51 (4) and 0.49 (4), while the C and H atoms were refined with occupancies of 0.320 (18) and 0.680 (18).

Related literature

For general background, see: Davidson & Bernhard (1948 [triangle]); Meldrum (1908 [triangle]); Muller et al. (2005 [triangle]); Ramachary et al. (2003 [triangle]); Tietze & Beifuss (1993 [triangle]); Tietze et al. (2001 [triangle]). For related structures, see: Chande & Khanwelkar (2005 [triangle]); Ramachary & Barbas (2004 [triangle]). For bond-length data, see: Allen et al. (1987 [triangle]). For ring-puckering parameters, see: Cremer & Pople (1975 [triangle]). For graph-set notation, see: Bernstein et al. (1995 [triangle]).

An external file that holds a picture, illustration, etc.
Object name is e-65-o1151-scheme1.jpg

Experimental

Crystal data

  • C26H26Br2O6
  • M r = 594.29
  • Triclinic, An external file that holds a picture, illustration, etc.
Object name is e-65-o1151-efi1.jpg
  • a = 7.356 (3) Å
  • b = 12.590 (5) Å
  • c = 14.852 (6) Å
  • α = 69.787 (6)°
  • β = 87.415 (7)°
  • γ = 79.243 (6)°
  • V = 1267.8 (9) Å3
  • Z = 2
  • Mo Kα radiation
  • μ = 3.24 mm−1
  • T = 298 K
  • 0.18 × 0.11 × 0.09 mm

Data collection

  • Bruker SMART CCD area-detector diffractometer
  • Absorption correction: multi-scan (SADABS; Sheldrick, 1996 [triangle]) T min = 0.594, T max = 0.759
  • 6454 measured reflections
  • 4330 independent reflections
  • 1413 reflections with I > 2σ(I)
  • R int = 0.060

Refinement

  • R[F 2 > 2σ(F 2)] = 0.073
  • wR(F 2) = 0.146
  • S = 1.00
  • 4330 reflections
  • 327 parameters
  • H-atom parameters constrained
  • Δρmax = 0.44 e Å−3
  • Δρmin = −0.32 e Å−3

Data collection: SMART (Bruker, 1998 [triangle]); cell refinement: SAINT (Bruker, 1998 [triangle]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 [triangle]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 [triangle]); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997 [triangle]) and PLATON (Spek, 2009 [triangle]); software used to prepare material for publication: SHELXL97.

Table 1
Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536809014251/hk2666sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536809014251/hk2666Isup2.hkl

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Acknowledgments

We thank the Natural Science Foundation of China (grant No. 20672090) and the Natural Science Foundation of Jiangsu Province (grant No. BK2006033).

supplementary crystallographic information

Comment

Over the past few decades, Meldrum's acid (2,2-dimethyl-1,3-dioxane-4,6-dione) (Tietze & Beifuss, 1993; Tietze et al., 2001) has been used as a versatile organic reagent (Ramachary et al., 2003; Muller et al., 2005) and its derivatives are very useful building blocks in synthetic organic chemistry (Davidson & Bernhard, 1948; Meldrum, 1908). Spirocyclic compounds including a Meldrum's acid unit are attractive intermediates in the syntheses of natural products and in medicinal chemistry. Thus, the synthesis of new highly substituted spiro ring system with a Meldrum's acid unit has attracted widespread attention (Ramachary & Barbas, 2004; Chande & Khanwelkar, 2005). We report herein the crystal structure of the title compound.

In the molecule of the title compound (Fig. 1), the bond lengths (Allen et al., 1987) and angles are within normal ranges. Ring A (C4-C9) is not planar, having total puckering amplitude, QT, of 0.576 (3) Å and chair conformation [[var phi] = -150.30 (3) and θ = 3.77 (3) °] (Cremer & Pople, 1975). Rings D (C12-C17) and E (C18-C23) are, of course, planar, and they are oriented at a dihedral angle of D/E = 77.21 (3)°. Rings B (O1/O2/C1-C4) and C (O5/O6/C7/C24/C25) adopt envelope conformations, with atoms C2 and O5 displaced by -0.184 (3) and -0.291 (3) Å from the planes of the other rings atoms.

In the crystal structure, weak intermolecular C-H···O interactions (Table 1) link the molecules into centrosymmetric dimers forming R22(14) ring motifs (Fig. 2) (Bernstein et al., 1995), in which they may be effective in the stabilization of the structure.

Experimental

The title compound was prepared by the reaction of 1,2-diarylidenehydrazine (2 mmol), Meldrum's acid (5 mmol), HOAc (4 mL) and (S)-1,2-propanediol (8 ml). Upon completion, the reaction mixture was cooled to room temperature, and introduced into water. The solid was collected by washing with water. The combined solid was purified by ethanol.

Refinement

The Br2, C25, H25, C26, H26A, H26B and H26C atoms were disordered. During the refinement process, the disordered C and H atoms were refined with occupancies of 0.320 (18) and 0.680 (18), while Br atoms were refined with occupancies of 0.51 (4) and 0.49 (4). H atoms were positioned geometrically, with C-H = 0.93, 0.98, 0.97 and 0.96 Å for aromatic, methine, methylene and methyl H, respectively, and constrained to ride on their parent atoms, with Uiso(H) = xUeq(C), where x = 1.5 for methyl H and x = 1.2 for all other H atoms.

Figures

Fig. 1.
The molecular structure of the title molecule, with the atom-numbering scheme. Displacement ellipsoids are drawn at the 30% probability level.
Fig. 2.
A partial packing diagram of the title compound. Hydrogen bonds are shown as dashed lines.

Crystal data

C26H26Br2O6Z = 2
Mr = 594.29F(000) = 600
Triclinic, P1Dx = 1.557 Mg m3
Hall symbol: -P 1Mo Kα radiation, λ = 0.71073 Å
a = 7.356 (3) ÅCell parameters from 920 reflections
b = 12.590 (5) Åθ = 2.6–25.3°
c = 14.852 (6) ŵ = 3.24 mm1
α = 69.787 (6)°T = 298 K
β = 87.415 (7)°Prism, colorless
γ = 79.243 (6)°0.18 × 0.11 × 0.09 mm
V = 1267.8 (9) Å3

Data collection

Bruker SMART CCD area-detector diffractometer4330 independent reflections
Radiation source: fine-focus sealed tube1413 reflections with I > 2σ(I)
graphiteRint = 0.060
[var phi] and ω scansθmax = 25.0°, θmin = 1.9°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)h = −8→4
Tmin = 0.594, Tmax = 0.759k = −14→14
6454 measured reflectionsl = −17→16

Refinement

Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.073H-atom parameters constrained
wR(F2) = 0.146w = 1/[σ2(Fo2) + (0.038P)2] where P = (Fo2 + 2Fc2)/3
S = 1.00(Δ/σ)max < 0.001
4330 reflectionsΔρmax = 0.44 e Å3
327 parametersΔρmin = −0.32 e Å3
Primary atom site location: structure-invariant direct methods

Special details

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. Atom C25 is disordered over two sites, C25 and C25', for which occupation factors were refined and converged to 0.320 (18) and 0.680 (18), respectively. Atom Br2 is disordered over two sites, Br2 and Br2', for which occupation factors were refined and converged to 0.51 (4) and 0.49 (4), respectively

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2)

xyzUiso*/UeqOcc. (<1)
Br1−0.42012 (15)0.06501 (8)1.10942 (7)0.0968 (5)
Br20.153 (4)0.9617 (10)0.6351 (8)0.129 (4)0.51 (4)
Br2'0.052 (4)0.9718 (7)0.6478 (10)0.133 (4)0.49 (4)
O10.0177 (8)0.4886 (5)0.8942 (4)0.0710 (15)
O2−0.2101 (7)0.5229 (5)0.7764 (4)0.0800 (16)
O30.2839 (8)0.3774 (4)0.9013 (4)0.0636 (16)
O4−0.1776 (7)0.4473 (4)0.6644 (4)0.0771 (17)
O50.2593 (9)0.2562 (5)0.5545 (4)0.1010 (19)
O60.4502 (10)0.2393 (5)0.6762 (4)0.0924 (17)
C10.1367 (14)0.4189 (7)0.8619 (6)0.057 (2)
C2−0.1683 (13)0.5300 (8)0.8662 (7)0.067 (2)
C3−0.1111 (14)0.4561 (7)0.7342 (7)0.068 (2)
C40.0841 (11)0.4000 (6)0.7706 (6)0.0578 (18)
C50.1176 (11)0.2655 (6)0.7948 (5)0.0652 (19)
H50.24110.23570.82500.078*
C60.1253 (13)0.2337 (7)0.7058 (6)0.084 (2)
H6A0.00470.26000.67400.100*
H6B0.15400.15050.72390.100*
C70.2707 (14)0.2862 (7)0.6355 (7)0.082 (2)
C80.2277 (12)0.4198 (7)0.6086 (6)0.081 (2)
H8A0.31870.45320.56360.098*
H8B0.10680.44980.57720.098*
C90.2306 (11)0.4533 (6)0.6926 (6)0.069 (2)
H90.35360.42000.72270.083*
C10−0.2069 (13)0.6528 (7)0.8562 (6)0.106 (3)
H10A−0.33370.68470.83650.158*
H10B−0.12740.69320.80890.158*
H10C−0.18450.66030.91670.158*
C11−0.2822 (11)0.4550 (6)0.9417 (5)0.076 (2)
H11A−0.41120.48040.92410.114*
H11B−0.26180.46111.00290.114*
H11C−0.24540.37630.94540.114*
C12−0.0149 (12)0.2112 (6)0.8688 (6)0.0561 (19)
C130.0441 (12)0.1672 (6)0.9644 (6)0.068 (2)
H130.16480.16720.98070.081*
C14−0.0782 (13)0.1233 (6)1.0353 (6)0.072 (2)
H14−0.03910.09481.09930.087*
C15−0.2547 (13)0.1210 (6)1.0128 (7)0.064 (2)
C16−0.3171 (11)0.1642 (6)0.9171 (6)0.067 (2)
H16−0.43770.16400.90090.080*
C17−0.1928 (13)0.2069 (6)0.8477 (6)0.069 (2)
H17−0.23110.23400.78360.083*
C180.2047 (12)0.5829 (6)0.6711 (6)0.061 (2)
C190.3090 (12)0.6205 (7)0.7226 (6)0.078 (2)
H190.40120.56860.76450.094*
C200.2792 (13)0.7354 (7)0.7134 (6)0.093 (3)
H200.35130.76170.74810.111*
C210.1409 (15)0.8104 (7)0.6517 (7)0.085 (3)
C220.0427 (13)0.7738 (7)0.5975 (6)0.081 (2)
H22−0.04530.82570.55300.097*
C230.0739 (12)0.6600 (7)0.6087 (6)0.072 (2)
H230.00370.63440.57250.086*
C240.4398 (14)0.2316 (9)0.5185 (7)0.130 (3)
H24A0.46610.29650.46450.156*
H24B0.45420.16420.49940.156*
C250.5598 (15)0.2100 (9)0.6036 (8)0.119 (3)0.320 (18)
H250.59570.28580.57740.142*0.320 (18)
C260.755 (3)0.147 (3)0.602 (2)0.160 (9)0.320 (18)
H26A0.82230.14020.65830.240*0.320 (18)
H26B0.81570.18890.54590.240*0.320 (18)
H26C0.75250.07140.60090.240*0.320 (18)
C25'0.5598 (15)0.2100 (9)0.6036 (8)0.119 (3)0.680 (18)
H25'0.66100.25370.58580.142*0.680 (18)
C26'0.633 (3)0.0856 (14)0.6492 (12)0.201 (8)0.680 (18)
H26D0.69630.07250.70820.302*0.680 (18)
H26E0.71680.05960.60680.302*0.680 (18)
H26F0.53180.04410.66240.302*0.680 (18)

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
Br10.0912 (9)0.0934 (8)0.1038 (8)−0.0385 (6)0.0252 (6)−0.0232 (6)
Br20.173 (10)0.061 (2)0.150 (3)−0.016 (4)−0.045 (5)−0.030 (2)
Br2'0.173 (10)0.047 (2)0.170 (4)−0.003 (4)−0.049 (6)−0.027 (2)
O10.065 (4)0.081 (3)0.077 (3)0.006 (3)−0.006 (3)−0.048 (3)
O20.070 (4)0.094 (3)0.079 (3)0.013 (3)−0.007 (3)−0.047 (3)
O30.058 (4)0.055 (3)0.076 (4)−0.003 (3)−0.012 (3)−0.022 (3)
O40.070 (4)0.078 (4)0.084 (4)−0.002 (3)−0.025 (3)−0.032 (3)
O50.110 (4)0.106 (4)0.085 (4)0.006 (3)0.006 (3)−0.043 (3)
O60.106 (4)0.095 (4)0.086 (4)−0.005 (3)0.007 (3)−0.049 (3)
C10.059 (4)0.055 (4)0.066 (4)−0.015 (4)0.003 (4)−0.028 (3)
C20.059 (5)0.078 (5)0.072 (5)0.008 (5)−0.022 (5)−0.042 (4)
C30.075 (4)0.060 (4)0.074 (4)−0.017 (4)−0.005 (4)−0.027 (4)
C40.059 (4)0.054 (3)0.069 (4)−0.012 (3)0.003 (3)−0.031 (3)
C50.073 (4)0.062 (4)0.072 (4)−0.014 (3)0.004 (4)−0.037 (3)
C60.095 (4)0.070 (4)0.087 (4)−0.008 (4)0.002 (4)−0.032 (4)
C70.094 (5)0.081 (4)0.078 (5)0.001 (4)0.005 (4)−0.046 (4)
C80.090 (4)0.077 (4)0.078 (4)−0.016 (4)0.001 (4)−0.028 (4)
C90.080 (4)0.060 (4)0.074 (4)−0.018 (3)0.006 (4)−0.028 (3)
C100.107 (7)0.088 (6)0.116 (7)0.019 (6)−0.015 (6)−0.044 (6)
C110.067 (6)0.090 (6)0.082 (6)−0.012 (5)−0.002 (5)−0.045 (5)
C120.055 (4)0.054 (4)0.072 (4)−0.016 (4)0.001 (4)−0.035 (3)
C130.063 (5)0.061 (4)0.080 (5)−0.015 (4)0.002 (4)−0.024 (4)
C140.074 (6)0.062 (4)0.082 (5)−0.016 (4)0.003 (5)−0.024 (4)
C150.063 (5)0.056 (4)0.079 (5)−0.024 (4)0.004 (5)−0.026 (4)
C160.057 (5)0.066 (5)0.089 (6)−0.034 (4)0.003 (5)−0.028 (4)
C170.081 (5)0.061 (4)0.071 (4)−0.016 (4)−0.007 (4)−0.027 (4)
C180.072 (4)0.053 (4)0.064 (4)−0.016 (4)−0.003 (4)−0.026 (3)
C190.085 (5)0.064 (4)0.089 (5)−0.027 (4)−0.012 (4)−0.021 (4)
C200.108 (6)0.064 (5)0.104 (5)−0.025 (5)−0.037 (5)−0.017 (5)
C210.106 (6)0.045 (4)0.101 (6)−0.021 (5)−0.022 (5)−0.013 (4)
C220.098 (6)0.049 (4)0.088 (5)−0.010 (4)−0.030 (5)−0.011 (4)
C230.083 (5)0.057 (4)0.075 (4)−0.021 (4)−0.009 (4)−0.016 (4)
C240.113 (6)0.148 (6)0.118 (6)0.004 (6)0.001 (6)−0.044 (5)
C250.106 (5)0.123 (5)0.106 (5)0.021 (5)0.010 (4)−0.037 (4)
C260.156 (15)0.138 (14)0.150 (14)0.013 (14)0.011 (14)−0.026 (13)
C25'0.106 (5)0.123 (5)0.106 (5)0.021 (5)0.010 (4)−0.037 (4)
C26'0.179 (13)0.184 (12)0.180 (12)0.009 (11)0.044 (11)−0.011 (11)

Geometric parameters (Å, °)

Br1—C151.870 (8)C11—H11A0.9600
Br2—C211.853 (12)C11—H11B0.9600
Br2'—C211.997 (15)C11—H11C0.9600
O1—C11.316 (9)C12—C171.374 (10)
O1—C21.397 (9)C12—C131.391 (10)
O2—C31.313 (9)C13—C141.386 (9)
O2—C21.419 (8)C13—H130.9300
O3—C11.193 (9)C14—C151.363 (10)
O4—C31.213 (9)C14—H140.9300
O5—C71.390 (8)C15—C161.400 (10)
O5—C241.428 (9)C16—C171.380 (9)
O6—C71.411 (9)C16—H160.9300
O6—C251.426 (9)C17—H170.9300
C1—C41.534 (10)C18—C231.355 (10)
C2—C101.475 (10)C18—C191.356 (10)
C2—C111.525 (10)C19—C201.381 (10)
C3—C41.510 (11)C19—H190.9300
C4—C51.577 (9)C20—C211.376 (11)
C4—C91.604 (9)C20—H200.9300
C5—C121.503 (9)C21—C221.347 (10)
C5—C61.504 (9)C22—C231.360 (10)
C5—H50.9800C22—H220.9300
C6—C71.535 (10)C23—H230.9300
C6—H6A0.9700C24—C251.492 (10)
C6—H6B0.9700C24—H24A0.9700
C7—C81.562 (10)C24—H24B0.9700
C8—C91.450 (9)C25—C261.512 (16)
C8—H8A0.9700C25—H250.9800
C8—H8B0.9700C26—H26A0.9600
C9—C181.526 (9)C26—H26B0.9600
C9—H90.9800C26—H26C0.9600
C10—H10A0.9600C26'—H26D0.9600
C10—H10B0.9600C26'—H26E0.9600
C10—H10C0.9600C26'—H26F0.9600
C1—O1—C2126.5 (8)H11A—C11—H11C109.5
C3—O2—C2126.0 (7)H11B—C11—H11C109.5
C7—O5—C24110.3 (8)C17—C12—C13118.4 (8)
C7—O6—C25105.9 (8)C17—C12—C5123.7 (8)
O3—C1—O1119.5 (9)C13—C12—C5117.8 (8)
O3—C1—C4122.3 (9)C14—C13—C12119.5 (8)
O1—C1—C4118.1 (8)C14—C13—H13120.3
O1—C2—O2113.3 (7)C12—C13—H13120.3
O1—C2—C10106.9 (8)C15—C14—C13121.1 (9)
O2—C2—C10107.4 (7)C15—C14—H14119.4
O1—C2—C11107.3 (7)C13—C14—H14119.4
O2—C2—C11107.5 (7)C14—C15—C16120.5 (8)
C10—C2—C11114.8 (8)C14—C15—Br1120.7 (8)
O4—C3—O2118.2 (10)C16—C15—Br1118.8 (7)
O4—C3—C4122.9 (9)C17—C16—C15117.4 (8)
O2—C3—C4118.8 (9)C17—C16—H16121.3
C3—C4—C1114.0 (8)C15—C16—H16121.3
C3—C4—C5111.8 (7)C12—C17—C16123.0 (9)
C1—C4—C5106.2 (6)C12—C17—H17118.5
C3—C4—C9110.4 (7)C16—C17—H17118.5
C1—C4—C9104.9 (6)C23—C18—C19119.1 (8)
C5—C4—C9109.2 (6)C23—C18—C9123.1 (8)
C12—C5—C6114.8 (6)C19—C18—C9117.7 (8)
C12—C5—C4111.2 (6)C18—C19—C20120.4 (9)
C6—C5—C4112.0 (6)C18—C19—H19119.8
C12—C5—H5106.0C20—C19—H19119.8
C6—C5—H5106.0C21—C20—C19118.7 (9)
C4—C5—H5106.0C21—C20—H20120.6
C5—C6—C7112.4 (7)C19—C20—H20120.6
C5—C6—H6A109.1C22—C21—C20120.7 (8)
C7—C6—H6A109.1C22—C21—Br2126.7 (9)
C5—C6—H6B109.1C20—C21—Br2111.0 (10)
C7—C6—H6B109.1C22—C21—Br2'115.6 (9)
H6A—C6—H6B107.9C20—C21—Br2'123.3 (9)
O5—C7—O6108.0 (7)Br2—C21—Br2'22.3 (3)
O5—C7—C6107.4 (8)C21—C22—C23119.1 (9)
O6—C7—C6110.3 (8)C21—C22—H22120.4
O5—C7—C8110.5 (7)C23—C22—H22120.4
O6—C7—C8111.3 (8)C18—C23—C22121.8 (9)
C6—C7—C8109.1 (7)C18—C23—H23119.1
C9—C8—C7111.6 (7)C22—C23—H23119.1
C9—C8—H8A109.3O5—C24—C25101.7 (8)
C7—C8—H8A109.3O5—C24—H24A111.4
C9—C8—H8B109.3C25—C24—H24A111.4
C7—C8—H8B109.3O5—C24—H24B111.4
H8A—C8—H8B108.0C25—C24—H24B111.4
C8—C9—C18114.6 (7)H24A—C24—H24B109.3
C8—C9—C4112.0 (6)O6—C25—C24109.5 (9)
C18—C9—C4109.8 (6)O6—C25—C26133.7 (15)
C8—C9—H9106.6C24—C25—C26116.0 (13)
C18—C9—H9106.6O6—C25—H2593.0
C4—C9—H9106.6C24—C25—H2593.0
C2—C10—H10A109.5C26—C25—H2593.0
C2—C10—H10B109.5C25—C26—H26A109.5
H10A—C10—H10B109.5C25—C26—H26B109.5
C2—C10—H10C109.5H26A—C26—H26B109.5
H10A—C10—H10C109.5C25—C26—H26C109.5
H10B—C10—H10C109.5H26A—C26—H26C109.5
C2—C11—H11A109.5H26B—C26—H26C109.5
C2—C11—H11B109.5H26D—C26'—H26E109.5
H11A—C11—H11B109.5H26D—C26'—H26F109.5
C2—C11—H11C109.5H26E—C26'—H26F109.5

Hydrogen-bond geometry (Å, °)

D—H···AD—HH···AD···AD—H···A
C23—H23···O5i0.932.603.286 (2)131

Symmetry codes: (i) −x, −y+1, −z+1.

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: HK2666).

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