PMCCPMCCPMCC

Search tips
Search criteria 

Advanced

 
Logo of actaeInternational Union of Crystallographysearchopen accessarticle submissionjournal home pagethis article
 
Acta Crystallogr Sect E Struct Rep Online. 2010 March 1; 66(Pt 3): o703.
Published online 2010 February 27. doi:  10.1107/S160053681000677X
PMCID: PMC2983507

Methyl 3,5-bis­[(4-hydroxy­methyl-2-methoxy­phen­oxy)meth­yl]benzoate

Abstract

In the title compound, C26H28O8, the central aromatic ring forms dihedral angles of 24.32 (11) and 80.19 (7)° with the two adjoining vanillyl alcohol rings. In the crystal, O—H(...)O hydrogen bonds connect the mol­ecules, forming a hydrogen-bonded sheet-like motif extended in the ab plane.

Related literature

For the synthesis of and background to adjoined vanillyl alcohols, see: Mough et al. (2004 [triangle]); Mough & Holman (2008 [triangle]). For background to cryptophanes, see: Brotin & Dutasta (2009 [triangle]).

An external file that holds a picture, illustration, etc.
Object name is e-66-0o703-scheme1.jpg

Experimental

Crystal data

  • C26H28O8
  • M r = 468.48
  • Triclinic, An external file that holds a picture, illustration, etc.
Object name is e-66-0o703-efi1.jpg
  • a = 4.7707 (12) Å
  • b = 14.844 (4) Å
  • c = 16.349 (4) Å
  • α = 99.801 (5)°
  • β = 95.692 (5)°
  • γ = 92.821 (5)°
  • V = 1132.7 (5) Å3
  • Z = 2
  • Mo Kα radiation
  • μ = 0.10 mm−1
  • T = 173 K
  • 0.50 × 0.25 × 0.05 mm

Data collection

  • Bruker SMART 1K diffractometer
  • Absorption correction: multi-scan (SADABS; Bruker, 2001 [triangle]) T min = 0.951, T max = 0.995
  • 6559 measured reflections
  • 4394 independent reflections
  • 2197 reflections with I > 2σ(I)
  • R int = 0.037

Refinement

  • R[F 2 > 2σ(F 2)] = 0.054
  • wR(F 2) = 0.128
  • S = 0.85
  • 4394 reflections
  • 312 parameters
  • H-atom parameters constrained
  • Δρmax = 0.40 e Å−3
  • Δρmin = −0.22 e Å−3

Data collection: SMART (Bruker, 2001 [triangle]); cell refinement: SAINT (Bruker, 2001 [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 (Farrugia, 1997 [triangle]), PLATON (Spek, 2009 [triangle]) and X-SEED (Barbour, 2001 [triangle]); software used to prepare material for publication: WinGX (Farrugia, 1999 [triangle]) and PLATON.

Table 1
Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablocks global, I. DOI: 10.1107/S160053681000677X/ng2730sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S160053681000677X/ng2730Isup2.hkl

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

Acknowledgments

The authors acknowledge the Higher Education Commission of Pakistan for providing a fellowship to MNA under the Inter­national Research Support Initiative Program (IRSIP). KTH acknowledges grant support from the National Science Foundation (DMR-0349316).

supplementary crystallographic information

Comment

Adjoined vanillyl alcohols have been used extensively in the synthesis of container-like host molecules known as cryptophanes (Brotin & Dutasta, 2009). Our group has used the title compound as a precursor for the synthesis of a m-xylyl bridged cryptophane (Mough et al., 2004) that displays uncommon conformational behavior and whose carboxylic acid derivative has been used as a ligand for the synthesis of coordination polymers possessing container-like components (Mough et al., 2008).

The title compounds consists of two vanillyl alcohol moieties linked by a 3,5 disubstituted methylbenzoate. The arene rings of the vanilliyl alcohol moieties A (C1/C2/C3/C4/C5/C6) and B (C19/C20/C21/C22/C23/C24) are oriented, respectively, at dihedral angles of 24.32(0.11)° and 80.19(0.07)° with respect to the central methyl benzoate ring C (C10/C11/C12/C13/C14/C15). The hydroxyl groups available at each end of molecule participate in chains of O–H···O type hydrogen bonds that extend along the a-axis in the crystal (Table 1, Fig. 2). The molecules are thus connected into a hydrogen bonded polymeric sheet that resides in the ab plane.

Experimental

The compound was prepared following the method of Mough et al. (2004).

Refinement

All the C–H and O–H, H-atoms were positioned geometrically and refined using a riding model with: d(C—H) = 0.95Å and 0.99 Å, Uiso = 1.2Ueq (C) for aromatic and methylene C atoms, d(C—H)=0.98Å Uiso = 1.5Ueq (C) for methyl, d(C—H)=0.84Å Uiso = 1.2Ueq (O) for Hydroxyl.

Figures

Fig. 1.
A thermal ellisoid plot of I, at 50% probability.
Fig. 2.
Unit cell packing diagram of I depicting the hydrogen bonds as dashed lines. Hydrogen atoms not involved in O—H···O hydrogen bonding have been omitted for clarity.

Crystal data

C26H28O8Z = 2
Mr = 468.48F(000) = 496
Triclinic, P1Dx = 1.374 Mg m3
Hall symbol: -P 1Mo Kα radiation, λ = 0.71073 Å
a = 4.7707 (12) ÅCell parameters from 1285 reflections
b = 14.844 (4) Åθ = 2.5–24.5°
c = 16.349 (4) ŵ = 0.10 mm1
α = 99.801 (5)°T = 173 K
β = 95.692 (5)°Needle, pale yellow
γ = 92.821 (5)°0.50 × 0.25 × 0.05 mm
V = 1132.7 (5) Å3

Data collection

Bruker SMART K1 diffractometer4394 independent reflections
Radiation source: fine-focus sealed tube2197 reflections with I > 2σ(I)
graphiteRint = 0.037
ω scanθmax = 26.0°, θmin = 1.7°
Absorption correction: multi-scan (SADABS; Bruker, 2001)h = −5→5
Tmin = 0.951, Tmax = 0.995k = −16→18
6559 measured reflectionsl = −18→20

Refinement

Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.054Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.128H-atom parameters constrained
S = 0.85w = 1/[σ2(Fo2) + (0.0568P)2] where P = (Fo2 + 2Fc2)/3
4394 reflections(Δ/σ)max < 0.001
312 parametersΔρmax = 0.40 e Å3
0 restraintsΔρmin = −0.22 e Å3

Special details

Geometry. All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'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 > 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)

xyzUiso*/Ueq
O10.8577 (4)0.44795 (11)0.18004 (10)0.0323 (5)
C10.3350 (6)0.66420 (18)0.21353 (17)0.0325 (7)
O20.6676 (4)0.49101 (12)0.32243 (10)0.0400 (5)
C20.4117 (6)0.61493 (18)0.27658 (17)0.0329 (7)
H20.34340.63100.32940.039*
O30.2404 (4)0.80315 (13)0.30289 (13)0.0490 (6)
H30.10810.83460.31910.059*
C30.5843 (6)0.54346 (18)0.26403 (16)0.0319 (7)
O41.3168 (6)0.15167 (15)−0.10157 (14)0.0725 (8)
C40.6859 (5)0.51921 (17)0.18579 (16)0.0285 (6)
O51.6491 (5)0.09734 (14)−0.02106 (13)0.0614 (7)
C50.6078 (5)0.56715 (18)0.12281 (16)0.0299 (7)
H50.67270.55080.06950.036*
O61.4405 (4)0.26847 (12)0.34342 (10)0.0352 (5)
C60.4340 (6)0.63941 (17)0.13746 (16)0.0319 (7)
H60.38280.67230.09390.038*
O71.1515 (4)0.28885 (12)0.46990 (11)0.0436 (5)
C70.1416 (6)0.74113 (18)0.22818 (17)0.0409 (8)
H7A0.13260.77420.18030.049*
H7B−0.05120.71570.23240.049*
O80.7672 (4)−0.11335 (12)0.34750 (13)0.0489 (6)
H80.6119−0.14070.32630.059*
C80.5065 (7)0.4943 (2)0.39253 (16)0.0499 (9)
H8A0.55030.55320.43030.075*
H8B0.55470.44430.42240.075*
H8C0.30450.48770.37270.075*
C90.9429 (6)0.41381 (17)0.10055 (15)0.0304 (7)
H9A1.04100.46370.07890.036*
H9B0.77550.38970.06070.036*
C101.1380 (6)0.33864 (17)0.10909 (16)0.0286 (6)
C111.2673 (5)0.32889 (17)0.18610 (16)0.0283 (6)
H111.22180.36730.23500.034*
C121.4638 (5)0.26345 (17)0.19325 (16)0.0287 (6)
C131.5267 (6)0.20702 (18)0.12191 (17)0.0351 (7)
H131.66230.16280.12610.042*
C141.3922 (6)0.21470 (18)0.04403 (17)0.0373 (7)
C151.1980 (6)0.28043 (17)0.03803 (17)0.0327 (7)
H151.10550.2856−0.01500.039*
C161.4431 (8)0.1529 (2)−0.0346 (2)0.0472 (9)
C171.7031 (9)0.0358 (2)−0.0969 (2)0.0867 (14)
H17A1.52720.0010−0.12260.130*
H17B1.8436−0.0066−0.08270.130*
H17C1.77460.0719−0.13630.130*
C181.6184 (6)0.25862 (18)0.27714 (16)0.0357 (7)
H18A1.70480.19900.27390.043*
H18B1.77300.30750.29040.043*
C191.2662 (5)0.19350 (18)0.34944 (16)0.0300 (7)
C201.2295 (6)0.11288 (18)0.29360 (16)0.0338 (7)
H201.32780.10600.24540.041*
C211.0492 (6)0.04030 (18)0.30645 (16)0.0353 (7)
H211.0240−0.01490.26660.042*
C220.9088 (6)0.04871 (18)0.37649 (16)0.0310 (7)
C230.9420 (6)0.13196 (18)0.43279 (16)0.0346 (7)
H230.84270.13880.48080.042*
C241.1169 (6)0.20460 (18)0.41988 (16)0.0318 (7)
C250.7190 (6)−0.02789 (18)0.39519 (17)0.0374 (7)
H25A0.7527−0.03110.45530.045*
H25B0.5194−0.01450.38300.045*
C260.9726 (7)0.3043 (2)0.53515 (18)0.0574 (10)
H26A0.77490.29210.51130.086*
H26B1.00320.36810.56390.086*
H26C1.01670.26340.57500.086*

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
O10.0385 (12)0.0315 (11)0.0290 (10)0.0110 (9)0.0096 (9)0.0052 (8)
C10.0261 (16)0.0276 (16)0.0426 (17)−0.0002 (12)0.0008 (14)0.0049 (13)
O20.0550 (14)0.0404 (12)0.0295 (10)0.0163 (10)0.0141 (10)0.0110 (9)
C20.0346 (17)0.0310 (17)0.0326 (16)0.0031 (13)0.0112 (14)−0.0002 (13)
O30.0348 (13)0.0368 (13)0.0694 (14)0.0063 (10)0.0067 (11)−0.0090 (11)
C30.0349 (17)0.0292 (17)0.0333 (16)0.0034 (13)0.0063 (14)0.0086 (13)
O40.120 (2)0.0577 (16)0.0399 (14)0.0244 (15)0.0195 (15)−0.0019 (12)
C40.0276 (16)0.0265 (16)0.0308 (15)−0.0001 (12)0.0068 (13)0.0020 (12)
O50.0712 (17)0.0463 (14)0.0649 (15)0.0127 (12)0.0290 (14)−0.0101 (12)
C50.0316 (17)0.0332 (16)0.0256 (14)0.0006 (13)0.0071 (13)0.0050 (12)
O60.0340 (12)0.0325 (12)0.0412 (11)0.0042 (9)0.0086 (10)0.0091 (9)
C60.0339 (17)0.0299 (16)0.0324 (16)0.0017 (13)0.0022 (14)0.0080 (13)
O70.0512 (14)0.0371 (12)0.0403 (11)−0.0025 (10)0.0139 (11)−0.0028 (10)
C70.0418 (19)0.0323 (17)0.0476 (18)0.0070 (14)0.0039 (16)0.0034 (14)
O80.0357 (13)0.0330 (12)0.0749 (15)0.0017 (9)0.0107 (12)−0.0023 (11)
C80.079 (3)0.044 (2)0.0330 (16)0.0115 (17)0.0238 (17)0.0128 (14)
C90.0321 (16)0.0332 (16)0.0266 (14)0.0019 (13)0.0064 (13)0.0058 (12)
C100.0297 (16)0.0279 (16)0.0292 (15)−0.0016 (12)0.0101 (13)0.0048 (12)
C110.0279 (16)0.0285 (16)0.0285 (15)−0.0008 (12)0.0090 (13)0.0020 (12)
C120.0264 (16)0.0254 (15)0.0359 (16)0.0016 (12)0.0084 (13)0.0072 (13)
C130.0308 (17)0.0282 (16)0.0499 (18)0.0056 (13)0.0171 (15)0.0083 (14)
C140.047 (2)0.0292 (17)0.0381 (17)−0.0022 (14)0.0216 (16)0.0051 (14)
C150.0369 (18)0.0280 (16)0.0338 (16)−0.0013 (13)0.0102 (14)0.0045 (13)
C160.061 (2)0.0284 (18)0.055 (2)0.0008 (16)0.027 (2)0.0027 (17)
C170.115 (4)0.055 (2)0.088 (3)0.012 (2)0.059 (3)−0.022 (2)
C180.0301 (17)0.0334 (17)0.0472 (18)0.0090 (13)0.0123 (15)0.0106 (14)
C190.0228 (16)0.0320 (17)0.0370 (16)0.0043 (13)0.0029 (13)0.0111 (13)
C200.0371 (18)0.0314 (17)0.0349 (15)0.0086 (14)0.0095 (14)0.0065 (13)
C210.0398 (18)0.0298 (17)0.0351 (16)0.0089 (14)0.0039 (14)0.0010 (13)
C220.0271 (16)0.0317 (17)0.0341 (15)0.0049 (13)0.0011 (13)0.0062 (13)
C230.0349 (17)0.0405 (18)0.0302 (15)0.0078 (14)0.0069 (13)0.0080 (13)
C240.0312 (17)0.0320 (17)0.0310 (15)0.0037 (13)0.0016 (13)0.0025 (13)
C250.0323 (17)0.0338 (18)0.0459 (17)0.0051 (13)0.0080 (15)0.0032 (14)
C260.071 (3)0.050 (2)0.0486 (19)−0.0013 (18)0.0276 (19)−0.0092 (16)

Geometric parameters (Å, °)

O1—C41.366 (3)C9—H9B0.9900
O1—C91.418 (3)C10—C111.380 (3)
C1—C61.372 (3)C10—C151.388 (3)
C1—C21.393 (4)C11—C121.394 (4)
C1—C71.506 (4)C11—H110.9500
O2—C31.372 (3)C12—C131.383 (3)
O2—C81.437 (3)C12—C181.506 (4)
C2—C31.375 (4)C13—C141.393 (4)
C2—H20.9500C13—H130.9500
O3—C71.422 (3)C14—C151.387 (4)
O3—H30.8400C14—C161.495 (4)
C3—C41.409 (3)C15—H150.9500
O4—C161.193 (4)C17—H17A0.9800
C4—C51.380 (3)C17—H17B0.9800
O5—C161.339 (4)C17—H17C0.9800
O5—C171.462 (3)C18—H18A0.9900
C5—C61.391 (4)C18—H18B0.9900
C5—H50.9500C19—C201.368 (3)
O6—C191.379 (3)C19—C241.404 (3)
O6—C181.434 (3)C20—C211.402 (3)
C6—H60.9500C20—H200.9500
O7—C241.366 (3)C21—C221.374 (3)
O7—C261.427 (3)C21—H210.9500
C7—H7A0.9900C22—C231.401 (3)
C7—H7B0.9900C22—C251.509 (3)
O8—C251.413 (3)C23—C241.388 (4)
O8—H80.8400C23—H230.9500
C8—H8A0.9800C25—H25A0.9900
C8—H8B0.9800C25—H25B0.9900
C8—H8C0.9800C26—H26A0.9800
C9—C101.503 (4)C26—H26B0.9800
C9—H9A0.9900C26—H26C0.9800
C4—O1—C9117.7 (2)C12—C13—H13119.8
C6—C1—C2118.4 (2)C14—C13—H13119.8
C6—C1—C7121.0 (3)C15—C14—C13119.7 (3)
C2—C1—C7120.5 (2)C15—C14—C16117.7 (3)
C3—O2—C8116.9 (2)C13—C14—C16122.6 (3)
C3—C2—C1121.4 (2)C14—C15—C10120.3 (3)
C3—C2—H2119.3C14—C15—H15119.8
C1—C2—H2119.3C10—C15—H15119.8
C7—O3—H3109.5O4—C16—O5123.3 (3)
O2—C3—C2125.1 (2)O4—C16—C14125.1 (3)
O2—C3—C4115.4 (2)O5—C16—C14111.6 (3)
C2—C3—C4119.5 (3)O5—C17—H17A109.5
O1—C4—C5125.8 (2)O5—C17—H17B109.5
O1—C4—C3114.9 (2)H17A—C17—H17B109.5
C5—C4—C3119.3 (2)O5—C17—H17C109.5
C16—O5—C17112.9 (3)H17A—C17—H17C109.5
C4—C5—C6119.9 (2)H17B—C17—H17C109.5
C4—C5—H5120.0O6—C18—C12113.4 (2)
C6—C5—H5120.0O6—C18—H18A108.9
C19—O6—C18117.38 (19)C12—C18—H18A108.9
C1—C6—C5121.4 (3)O6—C18—H18B108.9
C1—C6—H6119.3C12—C18—H18B108.9
C5—C6—H6119.3H18A—C18—H18B107.7
C24—O7—C26116.3 (2)C20—C19—O6125.7 (2)
O3—C7—C1110.5 (2)C20—C19—C24119.6 (2)
O3—C7—H7A109.5O6—C19—C24114.6 (2)
C1—C7—H7A109.5C19—C20—C21121.0 (2)
O3—C7—H7B109.5C19—C20—H20119.5
C1—C7—H7B109.5C21—C20—H20119.5
H7A—C7—H7B108.1C22—C21—C20120.2 (2)
C25—O8—H8109.5C22—C21—H21119.9
O2—C8—H8A109.5C20—C21—H21119.9
O2—C8—H8B109.5C21—C22—C23118.7 (3)
H8A—C8—H8B109.5C21—C22—C25122.7 (2)
O2—C8—H8C109.5C23—C22—C25118.6 (2)
H8A—C8—H8C109.5C24—C23—C22121.4 (2)
H8B—C8—H8C109.5C24—C23—H23119.3
O1—C9—C10108.8 (2)C22—C23—H23119.3
O1—C9—H9A109.9O7—C24—C23124.9 (2)
C10—C9—H9A109.9O7—C24—C19116.1 (2)
O1—C9—H9B109.9C23—C24—C19119.0 (2)
C10—C9—H9B109.9O8—C25—C22111.7 (2)
H9A—C9—H9B108.3O8—C25—H25A109.3
C11—C10—C15119.4 (3)C22—C25—H25A109.3
C11—C10—C9121.0 (2)O8—C25—H25B109.3
C15—C10—C9119.5 (2)C22—C25—H25B109.3
C10—C11—C12121.0 (2)H25A—C25—H25B107.9
C10—C11—H11119.5O7—C26—H26A109.5
C12—C11—H11119.5O7—C26—H26B109.5
C13—C12—C11119.2 (2)H26A—C26—H26B109.5
C13—C12—C18120.6 (2)O7—C26—H26C109.5
C11—C12—C18120.1 (2)H26A—C26—H26C109.5
C12—C13—C14120.4 (3)H26B—C26—H26C109.5
C6—C1—C2—C30.5 (4)C16—C14—C15—C10178.8 (2)
C7—C1—C2—C3178.9 (3)C11—C10—C15—C14−1.8 (4)
C8—O2—C3—C217.4 (4)C9—C10—C15—C14175.6 (2)
C8—O2—C3—C4−161.8 (2)C17—O5—C16—O40.3 (4)
C1—C2—C3—O2−179.3 (2)C17—O5—C16—C14179.8 (2)
C1—C2—C3—C4−0.1 (4)C15—C14—C16—O4−5.0 (4)
C9—O1—C4—C5−6.5 (4)C13—C14—C16—O4173.5 (3)
C9—O1—C4—C3173.5 (2)C15—C14—C16—O5175.5 (2)
O2—C3—C4—O1−1.3 (3)C13—C14—C16—O5−6.0 (4)
C2—C3—C4—O1179.4 (2)C19—O6—C18—C1277.3 (3)
O2—C3—C4—C5178.7 (2)C13—C12—C18—O6−141.4 (2)
C2—C3—C4—C5−0.6 (4)C11—C12—C18—O642.5 (3)
O1—C4—C5—C6−179.1 (2)C18—O6—C19—C20−6.0 (4)
C3—C4—C5—C61.0 (4)C18—O6—C19—C24174.4 (2)
C2—C1—C6—C5−0.2 (4)O6—C19—C20—C21179.1 (3)
C7—C1—C6—C5−178.6 (2)C24—C19—C20—C21−1.3 (4)
C4—C5—C6—C1−0.5 (4)C19—C20—C21—C22−1.0 (4)
C6—C1—C7—O3−130.8 (3)C20—C21—C22—C232.2 (4)
C2—C1—C7—O350.8 (3)C20—C21—C22—C25−178.1 (3)
C4—O1—C9—C10177.9 (2)C21—C22—C23—C24−1.3 (4)
O1—C9—C10—C11−17.5 (3)C25—C22—C23—C24179.0 (3)
O1—C9—C10—C15165.2 (2)C26—O7—C24—C23−6.2 (4)
C15—C10—C11—C122.1 (4)C26—O7—C24—C19172.0 (3)
C9—C10—C11—C12−175.3 (2)C22—C23—C24—O7177.2 (2)
C10—C11—C12—C13−0.7 (4)C22—C23—C24—C19−0.9 (4)
C10—C11—C12—C18175.5 (2)C20—C19—C24—O7−176.1 (2)
C11—C12—C13—C14−0.9 (4)O6—C19—C24—O73.5 (3)
C18—C12—C13—C14−177.1 (2)C20—C19—C24—C232.2 (4)
C12—C13—C14—C151.1 (4)O6—C19—C24—C23−178.1 (2)
C12—C13—C14—C16−177.4 (2)C21—C22—C25—O816.9 (4)
C13—C14—C15—C100.2 (4)C23—C22—C25—O8−163.4 (2)

Hydrogen-bond geometry (Å, °)

D—H···AD—HH···AD···AD—H···A
O3—H3···O8i0.841.902.731 (3)170
O8—H8···O3ii0.841.902.721 (3)167

Symmetry codes: (i) x−1, y+1, z; (ii) x, y−1, z.

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: NG2730).

References

  • Barbour, L. J. (2001). J. Supramol. Chem.1 189–191.
  • Brotin, T. & Dutasta, J.-P. (2009). Chem. Rev.109, 88–130. [PubMed]
  • Bruker (2001). SADABS, APEX2 and SAINT Bruker AXS Inc., Madison, Wisconsin, USA.
  • Farrugia, L. J. (1997). J. Appl. Cryst.30, 565.
  • Farrugia, L. J. (1999). J. Appl. Cryst.32, 837–838.
  • Mough, S. T., Goeltz, J. C. & Holman, K. T. (2004). Angew. Chem. Int. Ed.43, 5631–5635. [PubMed]
  • Mough, S. T. & Holman, K. T. (2008). Chem. Commun. pp. 1407–1409. [PubMed]
  • Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. [PubMed]
  • Spek, A. L. (2009). Acta Cryst. D65, 148–155. [PMC free article] [PubMed]

Articles from Acta Crystallographica Section E: Structure Reports Online are provided here courtesy of International Union of Crystallography