organic compounds
5-Butyl-5-(2-methyl-1H-inden-1-yl)-5H-dibenzo[b,d]silole
aX-ray Structural Laboratory, A.N. Nesmeyanov Institute of Organoelement Compounds, Vavilova St. 28, GSP-1, Moscow 119991, V-334, Russian Federation, and bDepartment of Chemistry, Lomonosov Moscow State University, 1/3 Leninskie Gory, GSP-1, Moscow 119991, Russian Federation
*Correspondence e-mail: medvedev.m.g@gmail.com
The structure of the title compound [systematic name: 8-butyl-8-(2-methyl-1H-inden-1-yl)-8-silatricyclo[7.4.0.02,3]trideca-1(13),2,4,6,9,11-hexaene], C26H26Si, at 110 K has orthorhombic (Pbca) symmetry. In the molecule, the butyl group displays an extended conformation with the C—C—C—C torsion angle of 176.8 (2)°. The dihedral angle between the biphenyl group and the indole group is 60.04 (2)°. The structure exhibits a weak intramolecular C—H⋯π interaction.
Keywords: crystal structure; silole; organosilicon compound.
CCDC reference: 1493435
Structure description
Benzannulated siloles are distinguish from their all-carbon analogues by their unique electronic structure (Yamaguchi & Tamao, 2005), and so are valuable building blocks for π-conjugated polymers. In the title molecule (Fig. 1), the butyl group displays an extended conformation with the C23—C24—C25—C26 torsion angle of 176.8 (2)°. All bond lengths are normal. The structure contains an intramolecular C—H⋯π interaction (Table 1).
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Synthesis and crystallization
This compound was obtained via treatment of 5,5-dichloro-5H-dibenzo[b,d]silole (Liu et al., 2002) with 1 equivalent of lithium salt of 2-methyl-1H-indene in THF followed by 1 equivalent of 2.5 M butyllithium in hexanes. Single crystals suitable for X-ray analysis were grown from an n-hexane solution at 243 K.
Refinement
Crystal data, data collection and structure .
details are summarized in Table 2Structural data
CCDC reference: 1493435
https://doi.org/10.1107/S2414314616011512/xu4011sup1.cif
contains datablocks global, I. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2414314616011512/xu4011Isup2.hkl
Supporting information file. DOI: https://doi.org/10.1107/S2414314616011512/xu4011Isup3.mol
Supporting information file. DOI: https://doi.org/10.1107/S2414314616011512/xu4011Isup4.cml
Data collection: SMART (Bruker, 2007); cell
SAINT (Bruker, 2007); data reduction: SAINT (Bruker, 2007); program(s) used to solve structure: SHLEXS (Sheldrick, 2008); program(s) used to refine structure: SHELXL (Sheldrick, 2015); molecular graphics: OLEX2 (Dolomanov et al., 2009); software used to prepare material for publication: OLEX2 (Dolomanov et al., 2009).C26H26Si | Dx = 1.197 Mg m−3 |
Mr = 366.56 | Mo Kα radiation, λ = 0.71073 Å |
Orthorhombic, Pbca | Cell parameters from 879 reflections |
a = 7.490 (2) Å | θ = 3–60° |
b = 18.968 (6) Å | µ = 0.12 mm−1 |
c = 28.635 (9) Å | T = 110 K |
V = 4068 (2) Å3 | Block, clear light yellow |
Z = 8 | 0.2 × 0.2 × 0.1 mm |
F(000) = 1568 |
Bruker SMART 1000 CCD diffractometer | Rint = 0.075 |
phi and ω scans | θmax = 30.0°, θmin = 2.2° |
25428 measured reflections | h = −10→7 |
5934 independent reflections | k = −23→26 |
2858 reflections with I > 2σ(I) | l = −40→36 |
Refinement on F2 | 0 restraints |
Least-squares matrix: full | Hydrogen site location: inferred from neighbouring sites |
R[F2 > 2σ(F2)] = 0.057 | H-atom parameters constrained |
wR(F2) = 0.148 | w = 1/[σ2(Fo2) + (0.0757P)2] where P = (Fo2 + 2Fc2)/3 |
S = 0.86 | (Δ/σ)max < 0.001 |
5934 reflections | Δρmax = 0.52 e Å−3 |
246 parameters | Δρmin = −0.24 e Å−3 |
Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes. |
x | y | z | Uiso*/Ueq | ||
Si1 | 0.79777 (7) | 0.42501 (3) | 0.11255 (2) | 0.02993 (15) | |
C1 | 0.8311 (2) | 0.49615 (10) | 0.15680 (6) | 0.0309 (4) | |
C2 | 0.8055 (3) | 0.56845 (10) | 0.15463 (7) | 0.0356 (5) | |
H2 | 0.7520 | 0.5887 | 0.1277 | 0.043* | |
C3 | 0.8574 (3) | 0.61143 (12) | 0.19140 (7) | 0.0418 (5) | |
H3 | 0.8412 | 0.6610 | 0.1894 | 0.050* | |
C4 | 0.9330 (3) | 0.58188 (12) | 0.23114 (7) | 0.0421 (5) | |
H4 | 0.9678 | 0.6115 | 0.2563 | 0.050* | |
C5 | 0.9581 (3) | 0.51005 (11) | 0.23455 (6) | 0.0370 (5) | |
H5 | 1.0097 | 0.4902 | 0.2619 | 0.044* | |
C6 | 0.9068 (2) | 0.46663 (10) | 0.19746 (6) | 0.0298 (4) | |
C7 | 0.9323 (2) | 0.38906 (11) | 0.19620 (6) | 0.0306 (4) | |
C8 | 1.0081 (3) | 0.34974 (11) | 0.23220 (6) | 0.0363 (5) | |
H8 | 1.0422 | 0.3722 | 0.2605 | 0.044* | |
C9 | 1.0334 (3) | 0.27829 (11) | 0.22679 (7) | 0.0401 (5) | |
H9 | 1.0844 | 0.2516 | 0.2515 | 0.048* | |
C10 | 0.9851 (3) | 0.24487 (12) | 0.18556 (7) | 0.0402 (5) | |
H10 | 1.0039 | 0.1957 | 0.1819 | 0.048* | |
C11 | 0.9089 (3) | 0.28411 (11) | 0.14960 (7) | 0.0364 (5) | |
H11 | 0.8759 | 0.2611 | 0.1214 | 0.044* | |
C12 | 0.8803 (3) | 0.35598 (10) | 0.15409 (6) | 0.0312 (4) | |
C13 | 0.5556 (3) | 0.41772 (11) | 0.09236 (6) | 0.0339 (5) | |
H13 | 0.5437 | 0.3888 | 0.0633 | 0.041* | |
C14 | 0.4367 (3) | 0.39131 (12) | 0.13116 (7) | 0.0398 (5) | |
C15 | 0.3431 (3) | 0.44517 (13) | 0.14891 (7) | 0.0450 (6) | |
H15 | 0.2677 | 0.4422 | 0.1755 | 0.054* | |
C16 | 0.3726 (3) | 0.50819 (13) | 0.12209 (7) | 0.0426 (5) | |
C17 | 0.3022 (3) | 0.57576 (14) | 0.12600 (9) | 0.0520 (6) | |
H17 | 0.2229 | 0.5873 | 0.1507 | 0.062* | |
C18 | 0.3497 (3) | 0.62550 (15) | 0.09335 (9) | 0.0579 (7) | |
H18 | 0.3032 | 0.6719 | 0.0959 | 0.069* | |
C19 | 0.4644 (3) | 0.60938 (13) | 0.05667 (8) | 0.0510 (6) | |
H19 | 0.4931 | 0.6444 | 0.0342 | 0.061* | |
C20 | 0.5374 (3) | 0.54217 (12) | 0.05272 (7) | 0.0425 (5) | |
H20 | 0.6170 | 0.5311 | 0.0280 | 0.051* | |
C21 | 0.4918 (3) | 0.49199 (11) | 0.08540 (7) | 0.0361 (5) | |
C22 | 0.4270 (3) | 0.31583 (12) | 0.14542 (7) | 0.0498 (6) | |
H22A | 0.3819 | 0.2876 | 0.1193 | 0.075* | |
H22B | 0.3462 | 0.3110 | 0.1722 | 0.075* | |
H22C | 0.5463 | 0.2993 | 0.1542 | 0.075* | |
C23 | 0.9444 (3) | 0.43149 (11) | 0.05995 (6) | 0.0356 (5) | |
H23A | 0.8986 | 0.4692 | 0.0392 | 0.043* | |
H23B | 1.0663 | 0.4449 | 0.0699 | 0.043* | |
C24 | 0.9537 (3) | 0.36211 (12) | 0.03241 (7) | 0.0468 (6) | |
H24A | 0.9976 | 0.3247 | 0.0536 | 0.056* | |
H24B | 0.8312 | 0.3491 | 0.0228 | 0.056* | |
C25 | 1.0688 (4) | 0.36308 (13) | −0.00973 (8) | 0.0585 (7) | |
H25A | 1.1902 | 0.3784 | −0.0006 | 0.070* | |
H25B | 1.0210 | 0.3983 | −0.0320 | 0.070* | |
C26 | 1.0816 (4) | 0.29247 (13) | −0.03404 (8) | 0.0625 (7) | |
H26A | 1.1471 | 0.2979 | −0.0634 | 0.094* | |
H26B | 0.9612 | 0.2747 | −0.0406 | 0.094* | |
H26C | 1.1447 | 0.2590 | −0.0139 | 0.094* |
U11 | U22 | U33 | U12 | U13 | U23 | |
Si1 | 0.0326 (3) | 0.0299 (3) | 0.0273 (3) | −0.0030 (2) | 0.0000 (2) | −0.0030 (2) |
C1 | 0.0260 (10) | 0.0348 (11) | 0.0319 (9) | −0.0018 (8) | 0.0007 (8) | −0.0039 (8) |
C2 | 0.0360 (11) | 0.0341 (12) | 0.0367 (10) | 0.0027 (9) | −0.0051 (9) | −0.0040 (9) |
C3 | 0.0390 (12) | 0.0347 (12) | 0.0516 (13) | 0.0048 (10) | −0.0053 (10) | −0.0128 (10) |
C4 | 0.0395 (13) | 0.0438 (14) | 0.0429 (11) | 0.0043 (10) | −0.0079 (9) | −0.0177 (10) |
C5 | 0.0347 (12) | 0.0444 (13) | 0.0319 (10) | 0.0002 (10) | −0.0025 (8) | −0.0076 (9) |
C6 | 0.0250 (10) | 0.0340 (11) | 0.0303 (9) | −0.0013 (8) | 0.0032 (8) | −0.0042 (8) |
C7 | 0.0253 (10) | 0.0369 (12) | 0.0297 (9) | −0.0035 (8) | 0.0049 (8) | 0.0019 (8) |
C8 | 0.0378 (12) | 0.0413 (13) | 0.0297 (10) | −0.0023 (10) | 0.0011 (8) | 0.0010 (9) |
C9 | 0.0429 (13) | 0.0394 (13) | 0.0381 (11) | −0.0019 (10) | 0.0005 (9) | 0.0110 (9) |
C10 | 0.0435 (13) | 0.0328 (12) | 0.0443 (11) | −0.0045 (10) | 0.0042 (10) | 0.0072 (9) |
C11 | 0.0417 (12) | 0.0347 (12) | 0.0328 (10) | −0.0063 (10) | 0.0009 (9) | −0.0007 (9) |
C12 | 0.0312 (10) | 0.0332 (11) | 0.0292 (9) | −0.0053 (9) | 0.0010 (8) | −0.0008 (8) |
C13 | 0.0337 (11) | 0.0389 (13) | 0.0289 (9) | −0.0053 (9) | 0.0006 (8) | −0.0060 (8) |
C14 | 0.0331 (12) | 0.0532 (15) | 0.0330 (10) | −0.0131 (10) | −0.0005 (9) | −0.0085 (10) |
C15 | 0.0321 (12) | 0.0651 (17) | 0.0377 (11) | −0.0076 (11) | 0.0023 (9) | −0.0134 (11) |
C16 | 0.0283 (11) | 0.0563 (16) | 0.0433 (12) | 0.0005 (10) | −0.0070 (9) | −0.0152 (11) |
C17 | 0.0349 (13) | 0.0624 (17) | 0.0587 (14) | 0.0091 (12) | −0.0070 (11) | −0.0187 (13) |
C18 | 0.0480 (15) | 0.0590 (18) | 0.0667 (16) | 0.0178 (13) | −0.0199 (13) | −0.0181 (14) |
C19 | 0.0517 (15) | 0.0484 (15) | 0.0530 (14) | 0.0066 (12) | −0.0206 (11) | −0.0010 (12) |
C20 | 0.0424 (13) | 0.0475 (14) | 0.0378 (11) | 0.0022 (11) | −0.0115 (9) | −0.0048 (10) |
C21 | 0.0303 (11) | 0.0433 (13) | 0.0346 (10) | −0.0007 (9) | −0.0115 (8) | −0.0083 (9) |
C22 | 0.0504 (15) | 0.0581 (16) | 0.0407 (11) | −0.0217 (12) | 0.0057 (10) | −0.0055 (11) |
C23 | 0.0357 (11) | 0.0363 (12) | 0.0347 (10) | 0.0014 (9) | 0.0053 (8) | −0.0013 (9) |
C24 | 0.0470 (13) | 0.0502 (15) | 0.0431 (12) | −0.0055 (11) | 0.0074 (10) | −0.0081 (10) |
C25 | 0.0693 (18) | 0.0516 (16) | 0.0545 (14) | 0.0009 (13) | 0.0223 (13) | −0.0068 (12) |
C26 | 0.0764 (19) | 0.0528 (16) | 0.0582 (15) | 0.0133 (14) | 0.0165 (14) | −0.0154 (13) |
Si1—C1 | 1.8678 (19) | C14—C22 | 1.491 (3) |
Si1—C12 | 1.874 (2) | C15—H15 | 0.9500 |
Si1—C13 | 1.909 (2) | C15—C16 | 1.438 (3) |
Si1—C23 | 1.8680 (19) | C16—C17 | 1.390 (3) |
C1—C2 | 1.386 (3) | C16—C21 | 1.413 (3) |
C1—C6 | 1.411 (3) | C17—H17 | 0.9500 |
C2—H2 | 0.9500 | C17—C18 | 1.375 (3) |
C2—C3 | 1.387 (3) | C18—H18 | 0.9500 |
C3—H3 | 0.9500 | C18—C19 | 1.391 (3) |
C3—C4 | 1.389 (3) | C19—H19 | 0.9500 |
C4—H4 | 0.9500 | C19—C20 | 1.392 (3) |
C4—C5 | 1.379 (3) | C20—H20 | 0.9500 |
C5—H5 | 0.9500 | C20—C21 | 1.378 (3) |
C5—C6 | 1.398 (2) | C22—H22A | 0.9800 |
C6—C7 | 1.484 (3) | C22—H22B | 0.9800 |
C7—C8 | 1.393 (3) | C22—H22C | 0.9800 |
C7—C12 | 1.414 (2) | C23—H23A | 0.9900 |
C8—H8 | 0.9500 | C23—H23B | 0.9900 |
C8—C9 | 1.377 (3) | C23—C24 | 1.536 (3) |
C9—H9 | 0.9500 | C24—H24A | 0.9900 |
C9—C10 | 1.388 (3) | C24—H24B | 0.9900 |
C10—H10 | 0.9500 | C24—C25 | 1.483 (3) |
C10—C11 | 1.393 (3) | C25—H25A | 0.9900 |
C11—H11 | 0.9500 | C25—H25B | 0.9900 |
C11—C12 | 1.386 (3) | C25—C26 | 1.512 (3) |
C13—H13 | 1.0000 | C26—H26A | 0.9800 |
C13—C14 | 1.510 (3) | C26—H26B | 0.9800 |
C13—C21 | 1.501 (3) | C26—H26C | 0.9800 |
C14—C15 | 1.339 (3) | ||
C1—Si1—C12 | 91.72 (9) | C14—C15—H15 | 124.7 |
C1—Si1—C13 | 112.64 (8) | C14—C15—C16 | 110.56 (19) |
C1—Si1—C23 | 114.88 (9) | C16—C15—H15 | 124.7 |
C12—Si1—C13 | 117.07 (9) | C17—C16—C15 | 131.7 (2) |
C23—Si1—C12 | 111.33 (9) | C17—C16—C21 | 120.0 (2) |
C23—Si1—C13 | 108.62 (9) | C21—C16—C15 | 108.3 (2) |
C2—C1—Si1 | 131.75 (15) | C16—C17—H17 | 120.7 |
C2—C1—C6 | 119.02 (17) | C18—C17—C16 | 118.7 (2) |
C6—C1—Si1 | 109.08 (14) | C18—C17—H17 | 120.7 |
C1—C2—H2 | 119.7 | C17—C18—H18 | 119.3 |
C1—C2—C3 | 120.58 (19) | C17—C18—C19 | 121.5 (2) |
C3—C2—H2 | 119.7 | C19—C18—H18 | 119.3 |
C2—C3—H3 | 120.0 | C18—C19—H19 | 119.8 |
C2—C3—C4 | 119.9 (2) | C18—C19—C20 | 120.4 (2) |
C4—C3—H3 | 120.0 | C20—C19—H19 | 119.8 |
C3—C4—H4 | 119.6 | C19—C20—H20 | 120.6 |
C5—C4—C3 | 120.81 (19) | C21—C20—C19 | 118.7 (2) |
C5—C4—H4 | 119.6 | C21—C20—H20 | 120.6 |
C4—C5—H5 | 120.3 | C16—C21—C13 | 107.86 (18) |
C4—C5—C6 | 119.42 (19) | C20—C21—C13 | 131.28 (19) |
C6—C5—H5 | 120.3 | C20—C21—C16 | 120.8 (2) |
C1—C6—C7 | 115.15 (16) | C14—C22—H22A | 109.5 |
C5—C6—C1 | 120.24 (19) | C14—C22—H22B | 109.5 |
C5—C6—C7 | 124.57 (18) | C14—C22—H22C | 109.5 |
C8—C7—C6 | 124.41 (17) | H22A—C22—H22B | 109.5 |
C8—C7—C12 | 120.37 (19) | H22A—C22—H22C | 109.5 |
C12—C7—C6 | 115.17 (17) | H22B—C22—H22C | 109.5 |
C7—C8—H8 | 120.0 | Si1—C23—H23A | 109.1 |
C9—C8—C7 | 119.99 (19) | Si1—C23—H23B | 109.1 |
C9—C8—H8 | 120.0 | H23A—C23—H23B | 107.8 |
C8—C9—H9 | 119.7 | C24—C23—Si1 | 112.61 (14) |
C8—C9—C10 | 120.60 (19) | C24—C23—H23A | 109.1 |
C10—C9—H9 | 119.7 | C24—C23—H23B | 109.1 |
C9—C10—H10 | 120.3 | C23—C24—H24A | 108.4 |
C9—C10—C11 | 119.4 (2) | C23—C24—H24B | 108.4 |
C11—C10—H10 | 120.3 | H24A—C24—H24B | 107.4 |
C10—C11—H11 | 119.3 | C25—C24—C23 | 115.71 (19) |
C12—C11—C10 | 121.36 (19) | C25—C24—H24A | 108.4 |
C12—C11—H11 | 119.3 | C25—C24—H24B | 108.4 |
C7—C12—Si1 | 108.79 (14) | C24—C25—H25A | 108.8 |
C11—C12—Si1 | 132.81 (14) | C24—C25—H25B | 108.8 |
C11—C12—C7 | 118.22 (18) | C24—C25—C26 | 113.6 (2) |
Si1—C13—H13 | 112.1 | H25A—C25—H25B | 107.7 |
C14—C13—Si1 | 111.22 (13) | C26—C25—H25A | 108.8 |
C14—C13—H13 | 112.1 | C26—C25—H25B | 108.8 |
C21—C13—Si1 | 105.95 (13) | C25—C26—H26A | 109.5 |
C21—C13—H13 | 112.1 | C25—C26—H26B | 109.5 |
C21—C13—C14 | 102.78 (17) | C25—C26—H26C | 109.5 |
C15—C14—C13 | 109.6 (2) | H26A—C26—H26B | 109.5 |
C15—C14—C22 | 127.1 (2) | H26A—C26—H26C | 109.5 |
C22—C14—C13 | 123.30 (19) | H26B—C26—H26C | 109.5 |
Si1—C1—C2—C3 | −173.53 (16) | C12—Si1—C1—C2 | 178.22 (19) |
Si1—C1—C6—C5 | 174.92 (14) | C12—Si1—C1—C6 | 2.78 (14) |
Si1—C1—C6—C7 | −2.8 (2) | C12—Si1—C23—C24 | 60.18 (17) |
Si1—C13—C14—C15 | 103.56 (18) | C12—C7—C8—C9 | 0.3 (3) |
Si1—C13—C14—C22 | −77.7 (2) | C13—Si1—C1—C2 | −61.4 (2) |
Si1—C13—C21—C16 | −107.51 (15) | C13—Si1—C1—C6 | 123.17 (13) |
Si1—C13—C21—C20 | 68.8 (2) | C13—Si1—C12—C7 | −118.75 (13) |
Si1—C23—C24—C25 | −179.64 (18) | C13—Si1—C12—C11 | 66.4 (2) |
C1—Si1—C12—C7 | −2.15 (14) | C13—Si1—C23—C24 | −70.15 (17) |
C1—Si1—C12—C11 | −177.0 (2) | C13—C14—C15—C16 | 6.1 (2) |
C1—Si1—C23—C24 | 162.69 (14) | C14—C13—C21—C16 | 9.3 (2) |
C1—C2—C3—C4 | −1.1 (3) | C14—C13—C21—C20 | −174.4 (2) |
C1—C6—C7—C8 | 178.61 (17) | C14—C15—C16—C17 | 177.9 (2) |
C1—C6—C7—C12 | 1.2 (2) | C14—C15—C16—C21 | 0.1 (2) |
C2—C1—C6—C5 | −1.2 (3) | C15—C16—C17—C18 | −176.9 (2) |
C2—C1—C6—C7 | −178.87 (16) | C15—C16—C21—C13 | −6.3 (2) |
C2—C3—C4—C5 | 0.3 (3) | C15—C16—C21—C20 | 176.95 (17) |
C3—C4—C5—C6 | 0.1 (3) | C16—C17—C18—C19 | 0.6 (3) |
C4—C5—C6—C1 | 0.4 (3) | C17—C16—C21—C13 | 175.67 (18) |
C4—C5—C6—C7 | 177.83 (18) | C17—C16—C21—C20 | −1.1 (3) |
C5—C6—C7—C8 | 1.0 (3) | C17—C18—C19—C20 | −1.4 (3) |
C5—C6—C7—C12 | −176.39 (18) | C18—C19—C20—C21 | 0.9 (3) |
C6—C1—C2—C3 | 1.5 (3) | C19—C20—C21—C13 | −175.58 (19) |
C6—C7—C8—C9 | −177.02 (18) | C19—C20—C21—C16 | 0.4 (3) |
C6—C7—C12—Si1 | 1.0 (2) | C21—C13—C14—C15 | −9.4 (2) |
C6—C7—C12—C11 | 176.75 (17) | C21—C13—C14—C22 | 169.30 (18) |
C7—C8—C9—C10 | 0.4 (3) | C21—C16—C17—C18 | 0.6 (3) |
C8—C7—C12—Si1 | −176.51 (14) | C22—C14—C15—C16 | −172.57 (19) |
C8—C7—C12—C11 | −0.8 (3) | C23—Si1—C1—C2 | 63.7 (2) |
C8—C9—C10—C11 | −0.6 (3) | C23—Si1—C1—C6 | −111.74 (14) |
C9—C10—C11—C12 | 0.0 (3) | C23—Si1—C12—C7 | 115.47 (14) |
C10—C11—C12—Si1 | 175.10 (16) | C23—Si1—C12—C11 | −59.4 (2) |
C10—C11—C12—C7 | 0.6 (3) | C23—C24—C25—C26 | 176.8 (2) |
Cg1 is the centroid of the C16–C21 ring. |
D—H···A | D—H | H···A | D···A | D—H···A |
C2—H2···Cg1 | 0.95 | 2.78 | 3.446 (3) | 128 |
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