Supporting information
Crystallographic Information File (CIF) https://doi.org/10.1107/S0108270107027606/gd3118sup1.cif | |
Structure factor file (CIF format) https://doi.org/10.1107/S0108270107027606/gd3118Isup2.hkl | |
Structure factor file (CIF format) https://doi.org/10.1107/S0108270107027606/gd3118IIsup3.hkl | |
Structure factor file (CIF format) https://doi.org/10.1107/S0108270107027606/gd3118IIIsup4.hkl | |
Structure factor file (CIF format) https://doi.org/10.1107/S0108270107027606/gd3118IVsup5.hkl | |
Structure factor file (CIF format) https://doi.org/10.1107/S0108270107027606/gd3118Vsup6.hkl |
CCDC references: 659133; 659134; 659135; 659136; 659137
The preparations of compounds (I)–(V) from the aldehyde precursors by Wittig, Corey-Fuchs and Bestmann reactions, including characterization by spectroscopic and analytical methods, were described previously by us (Bondarenko et al., 2004).
Acetylenic H atoms were refined freely. Other H atoms were included using a riding model, with C—H bond lengths fixed at 0.99 Å (methylene) or 0.95 Å (Csp2) and with Uiso(H) = 1.2Ueq(C). For compounds (III)–(V), which crystallize in non-centrosymmetric space groups, the anomalous scattering was negligible, and Friedel opposite reflections were therefore merged. For this reason, the Flack parameters are indeterminate. For compounds (III) and (V), this additionally means that the space groups P31 and P32 could not be distinguished. For consistency, P31 was chosen for both, which means that the enantiomer of (V) is opposite to that shown in the scheme (as noted in the Comment section). For compounds (III)–(V), and additionally for compound (I), which diffracted weakly, restraints to displacement parameters were employed (SIMU and DELU instructions in SHELXL97; Sheldrick, 1997) to improve the ratio of `observed' reflections to parameters (which would otherwise be less than 10).
We recently described the syntheses of 4-ethynyl[2.2]paracyclophane, (I), and the four isomeric disubstituted derivatives, 4,12-diethynyl-, (II), 4,13-diethynyl-, (III), 4,15-diethynyl-, (IV), and 4,16-diethynyl[2.2]paracyclophane, (V) (Bondarenko et al., 2004). These molecules are interesting building blocks for molecular scaffolding (Hopf & Dix, 2006). We are also interested in the structures of paracyclophane derivatives and, in particular, in their packing, and have presented a description of C—H···π interactions (Desiraju & Steiner, 1999) in some pseudo-geminally substituted derivatives (El Shaieb et al., 2003). Here, we present the crystal structures of compounds (I)–(V). The disubstituted compounds (II), (III), (IV) and (V) represent the substitution patterns pseudo-para, pseudo-meta, pseudo-geminal and pseudo-ortho, respectively. To the best of our knowledge, this is the first time that all four possible isomers with a given substituent have been structurally characterized by X-ray methods.
The molecules of compounds (I)–(V) are shown in Figs. 1–5. Those of (I), (III) and (V) are chiral, although all bulk samples were racemates. Nevertheless, compounds (III), (IV) and (V) crystallize by chance in chiral space groups. Compound (II) crystallizes with two independent molecules, each of which displays imposed inversion symmetry; for this reason, the standard IUPAC numbering cannot be fully implemented for (II). For compound (V), the enantiomer in Fig. 5 is opposite to that in the scheme.
Bond lengths and angles may be considered normal. In particular, the molecules show the distortions typical of [2.2]paracyclophane systems, e.g. lengthened C—C bonds and widened angles in the bridges, narrowed ring bond angles at the bridgehead atoms, and boatlike distortion of the rings (the bridgehead atoms lie significantly out of the plane of the other four ring atoms). These dimensions are summarized in Table 1. In the pseudo-geminal isomer, (IV), the separations between the atoms of the eclipsed triple-bond systems are C4···C15 3.170 (2), C17···C19 3.371 (2) and C18···C20 3.642 (3) Å. We have utilized such close contacts in related derivatives with double bonds to form ladderanes (see, for example, Hopf et al., 2005).
The molecular packing of all five compounds can be analysed in terms of C—H···π interactions, where the acceptor system can be the triple bond or the π electron density of the rings (Desiraju & Steiner, 1999). A summary of the observed contacts is given in Table 2. The packing of compound (I) involves layers of molecules parallel to the ab plane at z ≈ 1/4, 3/4, etc. One such layer is shown in Fig. 6. The molecules adopt a herringbone-type pattern, within which the three C—H···π interactions are accommodated. We have previously pointed out (El Shaieb et al., 2003) that many simple derivatives of [2.2]paracyclophane display a common combination of two axis lengths, one of ca 7.5 Å and the other of ca 11.5 Å. These values are consistent with the formation of hydrogen-bonded layers such as that observed for (I). Because the molecules are approximately equidimensional, mutual rotations within the layer can be tolerated without disturbing the overall pattern, and thus different types of H atom (bridge or ring) can act as donors. The substituents play a less important role: in general, they are directed perpendicularly away from the layers, and thus determine the interlayer interactions and, in turn, the space group and third axis length. The only requirement is that the substituents should not be too large or themselves determine the most important secondary interactions. In compound (I), the ethynyl substituent is even capable of accepting a hydrogen bond within the layer without disturbing the 7,11 pattern.
For the ring systems, it is not always clear whether the whole ring or only a part of it is the `true' acceptor of the hydrogen bond. For compound (I), the acceptor system of hydrogen bond No. 2 might be better expressed as the triangle of atoms C11/C12/C16 forming one angled end of the `boat'. For this grouping, the hydrogen-bond parameters would be 2.69 Å and 168°, shorter and more linear than the formal contact to the ring centroid.
The packing of compound (II) is shown in Fig. 7. It too involves a layer structure, but the 7,11 pattern is not observed. Instead, hydrogen bonds 1 and 2 (the latter involving an ethynyl acceptor) combine in layers parallel to (101). The other two hydrogen bonds are formed between layers. The acceptor for hydrogen bond 3 might be better expressed as the centroid of atoms C5–C7 (2.66 Å and 134°). Hydrogen bond 4 is a borderline case.
The 31 axis of compound (III) is clearly recognisable the packing diagram shown in Fig. 8. Within the 31 helices, the short hydrogen bond No. 1, with an ethynyl H atom as donor, links successive molecules (the `true' acceptor might be the centroid of atoms C11/C12/C16, with hydrogen-bond parameters of 2.56 Å, 138°). The other three hydrogen bonds, one short and two long, link adjacent helices. It is noteworthy that hydrogen bond 3 is from an ethynyl group to a symmetry equivalent of the same group.
With compound (IV), we return to the 7,11 pattern (Fig. 9), with one very short hydrogen bond (No. 1). The ethynyl groups play no role within the layer, but instead are involved in interlayer contacts.
Compound (V) crystallizes, like (III), in the space group P31. The packing diagram (Fig. 10) shows that the helices are assembled via a different type of hydrogen bond from those in (III), with a ring H atom as donor to the symmetry equivalent of the same ring. The first impression is that this is the only significant interaction (no other centroids or triple bonds appear to be involved in short contacts), but closer inspection reveals that the atom grouping C11/C12/C16 is the acceptor for hydrogen bond 2, which links adjacent helices.
For related literature, see: Bondarenko et al. (2004); Desiraju & Steiner (1999); El Shaieb, Narayanan, Hopf, Dix, Fischer, Jones, Ernst & Ibrom (2003); Hopf & Dix (2006); Hopf et al. (2005); Sheldrick (1997).
Data collection: XSCANS (Siemens, 1991) for (I); SMART (Bruker, 1998) for (II), (III), (IV), (V). Cell refinement: XSCANS for (I); SAINT (Bruker, 1998) for (II), (III), (IV), (V). Data reduction: XSCANS for (I); SAINT for (II), (III), (IV), (V). For all compounds, program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: XP (Siemens, 1994); software used to prepare material for publication: SHELXL97.
C18H16 | F(000) = 496 |
Mr = 232.31 | Dx = 1.232 Mg m−3 |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2ybc | Cell parameters from 62 reflections |
a = 7.6538 (14) Å | θ = 3.7–12.4° |
b = 11.022 (2) Å | µ = 0.07 mm−1 |
c = 15.056 (3) Å | T = 173 K |
β = 99.561 (16)° | Tablet, colourless |
V = 1252.4 (4) Å3 | 0.6 × 0.3 × 0.18 mm |
Z = 4 |
Siemens P4 diffractometer | Rint = 0.024 |
Radiation source: fine-focus sealed tube | θmax = 25.0°, θmin = 3.3° |
Graphite monochromator | h = 0→9 |
ω scans | k = −13→5 |
3461 measured reflections | l = −17→17 |
2191 independent reflections | 3 standard reflections every 247 reflections |
1267 reflections with I > 2σ(I) | intensity decay: none |
Refinement on F2 | Secondary atom site location: difference Fourier map |
Least-squares matrix: full | Hydrogen site location: inferred from neighbouring sites |
R[F2 > 2σ(F2)] = 0.042 | H atoms treated by a mixture of independent and constrained refinement |
wR(F2) = 0.103 | w = 1/[σ2(Fo2) + (0.0531P)2] where P = (Fo2 + 2Fc2)/3 |
S = 0.86 | (Δ/σ)max < 0.001 |
2191 reflections | Δρmax = 0.19 e Å−3 |
168 parameters | Δρmin = −0.17 e Å−3 |
167 restraints | Extinction correction: SHELXL97 (Sheldrick, 1997), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4 |
Primary atom site location: structure-invariant direct methods | Extinction coefficient: 0.010 (2) |
C18H16 | V = 1252.4 (4) Å3 |
Mr = 232.31 | Z = 4 |
Monoclinic, P21/c | Mo Kα radiation |
a = 7.6538 (14) Å | µ = 0.07 mm−1 |
b = 11.022 (2) Å | T = 173 K |
c = 15.056 (3) Å | 0.6 × 0.3 × 0.18 mm |
β = 99.561 (16)° |
Siemens P4 diffractometer | Rint = 0.024 |
3461 measured reflections | 3 standard reflections every 247 reflections |
2191 independent reflections | intensity decay: none |
1267 reflections with I > 2σ(I) |
R[F2 > 2σ(F2)] = 0.042 | 167 restraints |
wR(F2) = 0.103 | H atoms treated by a mixture of independent and constrained refinement |
S = 0.86 | Δρmax = 0.19 e Å−3 |
2191 reflections | Δρmin = −0.17 e Å−3 |
168 parameters |
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. |
x | y | z | Uiso*/Ueq | ||
C1 | 0.3240 (3) | 0.3294 (2) | 0.07414 (14) | 0.0463 (6) | |
H1A | 0.2652 | 0.3761 | 0.0213 | 0.056* | |
H1B | 0.3585 | 0.2495 | 0.0525 | 0.056* | |
C2 | 0.4959 (2) | 0.3996 (2) | 0.11990 (13) | 0.0360 (5) | |
H2A | 0.5941 | 0.3408 | 0.1352 | 0.043* | |
H2B | 0.5307 | 0.4582 | 0.0762 | 0.043* | |
C3 | 0.4704 (2) | 0.46641 (18) | 0.20368 (13) | 0.0283 (5) | |
C4 | 0.3583 (2) | 0.56743 (17) | 0.20060 (13) | 0.0275 (5) | |
C5 | 0.2775 (2) | 0.59538 (18) | 0.27469 (12) | 0.0302 (5) | |
H5 | 0.1993 | 0.6628 | 0.2714 | 0.036* | |
C6 | 0.3091 (2) | 0.52675 (19) | 0.35289 (13) | 0.0297 (5) | |
C7 | 0.4514 (2) | 0.44587 (19) | 0.36174 (12) | 0.0304 (5) | |
H7 | 0.4948 | 0.4109 | 0.4188 | 0.036* | |
C8 | 0.5296 (2) | 0.41630 (18) | 0.28807 (13) | 0.0299 (5) | |
H8 | 0.6257 | 0.3607 | 0.2953 | 0.036* | |
C9 | 0.1697 (2) | 0.5179 (2) | 0.41273 (13) | 0.0402 (6) | |
H9A | 0.0995 | 0.5937 | 0.4076 | 0.048* | |
H9B | 0.2287 | 0.5097 | 0.4761 | 0.048* | |
C10 | 0.0411 (3) | 0.4069 (2) | 0.38758 (15) | 0.0473 (6) | |
H10A | 0.0685 | 0.3438 | 0.4346 | 0.057* | |
H10B | −0.0823 | 0.4341 | 0.3872 | 0.057* | |
C11 | 0.0544 (2) | 0.3517 (2) | 0.29722 (14) | 0.0351 (5) | |
C12 | 0.1664 (3) | 0.25412 (19) | 0.29033 (14) | 0.0383 (5) | |
H12 | 0.1968 | 0.2008 | 0.3401 | 0.046* | |
C13 | 0.2342 (2) | 0.2335 (2) | 0.21217 (14) | 0.0371 (5) | |
H13 | 0.3090 | 0.1655 | 0.2086 | 0.045* | |
C14 | 0.1946 (2) | 0.3106 (2) | 0.13905 (13) | 0.0343 (5) | |
C15 | 0.0537 (2) | 0.39093 (19) | 0.13934 (13) | 0.0354 (5) | |
H15 | 0.0050 | 0.4325 | 0.0856 | 0.042* | |
C16 | −0.0156 (2) | 0.41044 (19) | 0.21755 (13) | 0.0347 (5) | |
H16 | −0.1123 | 0.4647 | 0.2167 | 0.042* | |
C17 | 0.3047 (2) | 0.63154 (19) | 0.11716 (14) | 0.0333 (5) | |
C18 | 0.2613 (3) | 0.6839 (2) | 0.04844 (15) | 0.0422 (6) | |
H18 | 0.225 (3) | 0.727 (2) | −0.0080 (14) | 0.055 (7)* |
U11 | U22 | U33 | U12 | U13 | U23 | |
C1 | 0.0454 (12) | 0.0519 (16) | 0.0416 (13) | 0.0006 (12) | 0.0069 (10) | −0.0146 (11) |
C2 | 0.0321 (11) | 0.0374 (14) | 0.0398 (12) | 0.0049 (10) | 0.0098 (9) | 0.0008 (10) |
C3 | 0.0208 (9) | 0.0271 (12) | 0.0370 (11) | −0.0039 (9) | 0.0048 (8) | 0.0009 (9) |
C4 | 0.0225 (9) | 0.0252 (12) | 0.0332 (10) | −0.0040 (9) | 0.0001 (8) | −0.0007 (9) |
C5 | 0.0227 (9) | 0.0240 (12) | 0.0419 (12) | 0.0002 (9) | −0.0002 (9) | −0.0067 (10) |
C6 | 0.0254 (9) | 0.0298 (12) | 0.0327 (11) | −0.0045 (9) | 0.0011 (8) | −0.0065 (9) |
C7 | 0.0250 (10) | 0.0327 (12) | 0.0308 (11) | −0.0053 (9) | −0.0030 (8) | 0.0017 (9) |
C8 | 0.0206 (9) | 0.0275 (12) | 0.0402 (11) | −0.0008 (9) | 0.0014 (8) | 0.0010 (9) |
C9 | 0.0360 (11) | 0.0476 (15) | 0.0372 (12) | −0.0020 (11) | 0.0063 (10) | −0.0103 (11) |
C10 | 0.0374 (11) | 0.0581 (17) | 0.0498 (13) | −0.0113 (12) | 0.0173 (10) | −0.0021 (12) |
C11 | 0.0246 (10) | 0.0371 (14) | 0.0437 (12) | −0.0127 (10) | 0.0060 (9) | −0.0014 (10) |
C12 | 0.0316 (11) | 0.0337 (14) | 0.0468 (13) | −0.0093 (10) | −0.0013 (10) | 0.0077 (11) |
C13 | 0.0296 (11) | 0.0275 (13) | 0.0520 (13) | −0.0003 (9) | 0.0002 (10) | −0.0059 (10) |
C14 | 0.0295 (10) | 0.0334 (13) | 0.0379 (11) | −0.0042 (10) | −0.0005 (9) | −0.0101 (10) |
C15 | 0.0273 (10) | 0.0341 (13) | 0.0406 (12) | −0.0056 (10) | −0.0068 (9) | −0.0022 (10) |
C16 | 0.0182 (9) | 0.0336 (13) | 0.0513 (13) | −0.0024 (9) | 0.0023 (9) | −0.0034 (10) |
C17 | 0.0303 (11) | 0.0298 (13) | 0.0385 (12) | 0.0017 (9) | 0.0019 (9) | −0.0028 (10) |
C18 | 0.0472 (13) | 0.0377 (14) | 0.0400 (13) | 0.0049 (12) | 0.0023 (11) | 0.0005 (12) |
C1—C14 | 1.517 (3) | C9—C10 | 1.576 (3) |
C1—C2 | 1.582 (3) | C9—H9A | 0.9900 |
C1—H1A | 0.9900 | C9—H9B | 0.9900 |
C1—H1B | 0.9900 | C10—C11 | 1.509 (3) |
C2—C3 | 1.501 (3) | C10—H10A | 0.9900 |
C2—H2A | 0.9900 | C10—H10B | 0.9900 |
C2—H2B | 0.9900 | C11—C16 | 1.390 (3) |
C3—C8 | 1.391 (2) | C11—C12 | 1.390 (3) |
C3—C4 | 1.401 (3) | C12—C13 | 1.382 (3) |
C4—C5 | 1.397 (3) | C12—H12 | 0.9500 |
C4—C17 | 1.440 (3) | C13—C14 | 1.384 (3) |
C5—C6 | 1.386 (3) | C13—H13 | 0.9500 |
C5—H5 | 0.9500 | C14—C15 | 1.396 (3) |
C6—C7 | 1.397 (3) | C15—C16 | 1.386 (3) |
C6—C9 | 1.509 (3) | C15—H15 | 0.9500 |
C7—C8 | 1.384 (3) | C16—H16 | 0.9500 |
C7—H7 | 0.9500 | C17—C18 | 1.183 (3) |
C8—H8 | 0.9500 | C18—H18 | 0.97 (2) |
C14—C1—C2 | 111.79 (16) | C6—C9—H9A | 109.1 |
C14—C1—H1A | 109.3 | C10—C9—H9A | 109.1 |
C2—C1—H1A | 109.3 | C6—C9—H9B | 109.1 |
C14—C1—H1B | 109.3 | C10—C9—H9B | 109.1 |
C2—C1—H1B | 109.3 | H9A—C9—H9B | 107.8 |
H1A—C1—H1B | 107.9 | C11—C10—C9 | 113.36 (16) |
C3—C2—C1 | 112.98 (15) | C11—C10—H10A | 108.9 |
C3—C2—H2A | 109.0 | C9—C10—H10A | 108.9 |
C1—C2—H2A | 109.0 | C11—C10—H10B | 108.9 |
C3—C2—H2B | 109.0 | C9—C10—H10B | 108.9 |
C1—C2—H2B | 109.0 | H10A—C10—H10B | 107.7 |
H2A—C2—H2B | 107.8 | C16—C11—C12 | 116.7 (2) |
C8—C3—C4 | 116.79 (18) | C16—C11—C10 | 121.1 (2) |
C8—C3—C2 | 120.30 (19) | C12—C11—C10 | 120.91 (19) |
C4—C3—C2 | 121.77 (17) | C13—C12—C11 | 121.0 (2) |
C5—C4—C3 | 119.90 (18) | C13—C12—H12 | 119.5 |
C5—C4—C17 | 119.22 (18) | C11—C12—H12 | 119.5 |
C3—C4—C17 | 120.19 (18) | C12—C13—C14 | 120.8 (2) |
C6—C5—C4 | 121.32 (18) | C12—C13—H13 | 119.6 |
C6—C5—H5 | 119.3 | C14—C13—H13 | 119.6 |
C4—C5—H5 | 119.3 | C13—C14—C15 | 117.03 (19) |
C5—C6—C7 | 116.91 (18) | C13—C14—C1 | 121.05 (19) |
C5—C6—C9 | 120.10 (17) | C15—C14—C1 | 120.2 (2) |
C7—C6—C9 | 121.25 (18) | C16—C15—C14 | 120.40 (19) |
C8—C7—C6 | 120.54 (18) | C16—C15—H15 | 119.8 |
C8—C7—H7 | 119.7 | C14—C15—H15 | 119.8 |
C6—C7—H7 | 119.7 | C15—C16—C11 | 120.93 (19) |
C7—C8—C3 | 121.33 (18) | C15—C16—H16 | 119.5 |
C7—C8—H8 | 119.3 | C11—C16—H16 | 119.5 |
C3—C8—H8 | 119.3 | C18—C17—C4 | 179.6 (2) |
C6—C9—C10 | 112.45 (16) | C17—C18—H18 | 179.9 (15) |
C14—C1—C2—C3 | −18.7 (3) | C7—C6—C9—C10 | −73.5 (2) |
C1—C2—C3—C8 | 99.3 (2) | C6—C9—C10—C11 | −13.9 (3) |
C1—C2—C3—C4 | −68.1 (2) | C9—C10—C11—C16 | −73.5 (2) |
C8—C3—C4—C5 | −15.3 (3) | C9—C10—C11—C12 | 93.4 (2) |
C2—C3—C4—C5 | 152.46 (18) | C16—C11—C12—C13 | 13.5 (3) |
C8—C3—C4—C17 | 174.15 (17) | C10—C11—C12—C13 | −153.96 (19) |
C2—C3—C4—C17 | −18.0 (3) | C11—C12—C13—C14 | 1.0 (3) |
C3—C4—C5—C6 | 1.7 (3) | C12—C13—C14—C15 | −14.7 (3) |
C17—C4—C5—C6 | 172.24 (17) | C12—C13—C14—C1 | 150.44 (19) |
C4—C5—C6—C7 | 13.2 (3) | C2—C1—C14—C13 | −68.3 (3) |
C4—C5—C6—C9 | −151.97 (18) | C2—C1—C14—C15 | 96.4 (2) |
C5—C6—C7—C8 | −14.3 (3) | C13—C14—C15—C16 | 13.9 (3) |
C9—C6—C7—C8 | 150.72 (18) | C1—C14—C15—C16 | −151.41 (19) |
C6—C7—C8—C3 | 0.5 (3) | C14—C15—C16—C11 | 0.6 (3) |
C4—C3—C8—C7 | 14.4 (3) | C12—C11—C16—C15 | −14.3 (3) |
C2—C3—C8—C7 | −153.61 (18) | C10—C11—C16—C15 | 153.16 (19) |
C5—C6—C9—C10 | 91.0 (2) |
C20H16 | Z = 2 |
Mr = 256.33 | F(000) = 272 |
Triclinic, P1 | Dx = 1.263 Mg m−3 |
Hall symbol: -P 1 | Mo Kα radiation, λ = 0.71073 Å |
a = 7.6316 (10) Å | Cell parameters from 3408 reflections |
b = 7.8177 (10) Å | θ = 2–28° |
c = 12.4446 (16) Å | µ = 0.07 mm−1 |
α = 78.125 (2)° | T = 143 K |
β = 72.339 (2)° | Prism, colourless |
γ = 73.971 (2)° | 0.42 × 0.28 × 0.26 mm |
V = 673.90 (15) Å3 |
Bruker SMART 1000 CCD area-detector diffractometer | 2953 reflections with I > 2σ(I) |
Radiation source: fine-focus sealed tube | Rint = 0.030 |
Graphite monochromator | θmax = 28.5°, θmin = 1.7° |
Detector resolution: 8.192 pixels mm-1 | h = −10→10 |
ω scans | k = −10→8 |
5064 measured reflections | l = −16→16 |
3383 independent reflections |
Refinement on F2 | Primary atom site location: structure-invariant direct methods |
Least-squares matrix: full | Secondary atom site location: difference Fourier map |
R[F2 > 2σ(F2)] = 0.045 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.126 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.08 | w = 1/[σ2(Fo2) + (0.073P)2 + 0.1405P] where P = (Fo2 + 2Fc2)/3 |
3383 reflections | (Δ/σ)max < 0.001 |
189 parameters | Δρmax = 0.35 e Å−3 |
0 restraints | Δρmin = −0.23 e Å−3 |
C20H16 | γ = 73.971 (2)° |
Mr = 256.33 | V = 673.90 (15) Å3 |
Triclinic, P1 | Z = 2 |
a = 7.6316 (10) Å | Mo Kα radiation |
b = 7.8177 (10) Å | µ = 0.07 mm−1 |
c = 12.4446 (16) Å | T = 143 K |
α = 78.125 (2)° | 0.42 × 0.28 × 0.26 mm |
β = 72.339 (2)° |
Bruker SMART 1000 CCD area-detector diffractometer | 2953 reflections with I > 2σ(I) |
5064 measured reflections | Rint = 0.030 |
3383 independent reflections |
R[F2 > 2σ(F2)] = 0.045 | 0 restraints |
wR(F2) = 0.126 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.08 | Δρmax = 0.35 e Å−3 |
3383 reflections | Δρmin = −0.23 e Å−3 |
189 parameters |
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. |
x | y | z | Uiso*/Ueq | ||
C1 | −0.29585 (15) | 0.12460 (15) | 0.69765 (9) | 0.0220 (2) | |
H1A | −0.4118 | 0.0781 | 0.7310 | 0.026* | |
H1B | −0.3218 | 0.2447 | 0.7210 | 0.026* | |
C2 | −0.12894 (15) | −0.00650 (15) | 0.74753 (9) | 0.0207 (2) | |
H2A | −0.0878 | 0.0604 | 0.7913 | 0.025* | |
H2B | −0.1771 | −0.1065 | 0.8005 | 0.025* | |
C3 | 0.03919 (14) | −0.08282 (14) | 0.65501 (8) | 0.0185 (2) | |
C4 | 0.17681 (14) | 0.01575 (13) | 0.59413 (9) | 0.0180 (2) | |
C5 | 0.28086 (14) | −0.01550 (14) | 0.48280 (9) | 0.0188 (2) | |
H5 | 0.3732 | 0.0513 | 0.4422 | 0.023* | |
C6 | 0.25060 (14) | −0.14330 (14) | 0.43092 (9) | 0.0187 (2) | |
C7 | 0.14599 (15) | −0.26576 (14) | 0.50073 (9) | 0.0200 (2) | |
H7 | 0.1463 | −0.3701 | 0.4728 | 0.024* | |
C8 | 0.04156 (15) | −0.23477 (14) | 0.61105 (9) | 0.0203 (2) | |
H8 | −0.0293 | −0.3184 | 0.6573 | 0.024* | |
C9 | 0.19561 (15) | 0.16540 (15) | 0.63745 (9) | 0.0210 (2) | |
C10 | 0.21447 (18) | 0.29073 (17) | 0.67032 (10) | 0.0281 (3) | |
H10 | 0.230 (3) | 0.392 (3) | 0.6952 (15) | 0.048 (5)* | |
C1' | 0.86046 (17) | 0.28377 (17) | 0.03764 (11) | 0.0287 (3) | |
H1'1 | 0.9060 | 0.3002 | 0.1005 | 0.034* | |
H1'2 | 0.9710 | 0.2245 | −0.0190 | 0.034* | |
C2' | 0.71548 (16) | 0.15666 (15) | 0.08652 (10) | 0.0250 (2) | |
H2'1 | 0.7586 | 0.0537 | 0.0426 | 0.030* | |
H2'2 | 0.7150 | 0.1086 | 0.1667 | 0.030* | |
C3' | 0.51609 (15) | 0.25307 (14) | 0.08092 (9) | 0.0197 (2) | |
C4' | 0.40181 (14) | 0.37610 (14) | 0.15719 (9) | 0.0185 (2) | |
C5' | 0.25753 (15) | 0.51451 (14) | 0.12501 (9) | 0.0203 (2) | |
H5' | 0.1805 | 0.5963 | 0.1768 | 0.024* | |
C6' | 0.22560 (14) | 0.53366 (15) | 0.01792 (9) | 0.0217 (2) | |
C7' | 0.30971 (16) | 0.38834 (16) | −0.04408 (9) | 0.0236 (2) | |
H7' | 0.2690 | 0.3837 | −0.1082 | 0.028* | |
C8' | 0.45248 (16) | 0.25044 (15) | −0.01283 (9) | 0.0226 (2) | |
H8' | 0.5077 | 0.1527 | −0.0560 | 0.027* | |
C9' | 0.44786 (15) | 0.37435 (14) | 0.26161 (9) | 0.0215 (2) | |
C10' | 0.48740 (18) | 0.37135 (16) | 0.34783 (10) | 0.0270 (3) | |
H10' | 0.520 (3) | 0.367 (3) | 0.4182 (16) | 0.051 (5)* |
U11 | U22 | U33 | U12 | U13 | U23 | |
C1 | 0.0207 (5) | 0.0245 (5) | 0.0183 (5) | −0.0001 (4) | −0.0047 (4) | −0.0050 (4) |
C2 | 0.0202 (5) | 0.0242 (5) | 0.0162 (5) | −0.0044 (4) | −0.0043 (4) | −0.0010 (4) |
C3 | 0.0175 (5) | 0.0197 (5) | 0.0168 (4) | −0.0026 (4) | −0.0060 (4) | 0.0002 (4) |
C4 | 0.0178 (4) | 0.0177 (5) | 0.0189 (5) | −0.0025 (4) | −0.0075 (4) | −0.0012 (4) |
C5 | 0.0161 (4) | 0.0198 (5) | 0.0192 (5) | −0.0033 (4) | −0.0048 (4) | −0.0007 (4) |
C6 | 0.0162 (4) | 0.0199 (5) | 0.0182 (5) | 0.0004 (4) | −0.0054 (4) | −0.0032 (4) |
C7 | 0.0202 (5) | 0.0170 (5) | 0.0236 (5) | −0.0014 (4) | −0.0089 (4) | −0.0033 (4) |
C8 | 0.0196 (5) | 0.0183 (5) | 0.0223 (5) | −0.0044 (4) | −0.0069 (4) | 0.0010 (4) |
C9 | 0.0202 (5) | 0.0230 (5) | 0.0193 (5) | −0.0045 (4) | −0.0059 (4) | −0.0012 (4) |
C10 | 0.0340 (6) | 0.0257 (6) | 0.0277 (6) | −0.0078 (5) | −0.0105 (5) | −0.0051 (4) |
C1' | 0.0214 (5) | 0.0294 (6) | 0.0329 (6) | −0.0042 (4) | −0.0115 (5) | 0.0052 (5) |
C2' | 0.0237 (5) | 0.0189 (5) | 0.0273 (5) | −0.0002 (4) | −0.0054 (4) | −0.0002 (4) |
C3' | 0.0215 (5) | 0.0160 (4) | 0.0195 (5) | −0.0062 (4) | −0.0031 (4) | 0.0012 (4) |
C4' | 0.0192 (5) | 0.0180 (5) | 0.0179 (5) | −0.0073 (4) | −0.0034 (4) | 0.0004 (4) |
C5' | 0.0175 (5) | 0.0208 (5) | 0.0213 (5) | −0.0060 (4) | −0.0025 (4) | −0.0018 (4) |
C6' | 0.0165 (5) | 0.0244 (5) | 0.0242 (5) | −0.0075 (4) | −0.0065 (4) | 0.0022 (4) |
C7' | 0.0253 (5) | 0.0294 (6) | 0.0199 (5) | −0.0144 (4) | −0.0065 (4) | 0.0002 (4) |
C8' | 0.0265 (5) | 0.0210 (5) | 0.0202 (5) | −0.0105 (4) | −0.0013 (4) | −0.0029 (4) |
C9' | 0.0224 (5) | 0.0185 (5) | 0.0217 (5) | −0.0054 (4) | −0.0042 (4) | −0.0004 (4) |
C10' | 0.0324 (6) | 0.0242 (5) | 0.0250 (5) | −0.0058 (5) | −0.0106 (5) | −0.0007 (4) |
C1—C6i | 1.5157 (14) | C1'—C6'ii | 1.5160 (16) |
C1—C2 | 1.5985 (15) | C1'—C2' | 1.5911 (16) |
C1—H1A | 0.9900 | C1'—H1'1 | 0.9900 |
C1—H1B | 0.9900 | C1'—H1'2 | 0.9900 |
C2—C3 | 1.5138 (14) | C2'—C3' | 1.5158 (15) |
C2—H2A | 0.9900 | C2'—H2'1 | 0.9900 |
C2—H2B | 0.9900 | C2'—H2'2 | 0.9900 |
C3—C8 | 1.4000 (15) | C3'—C8' | 1.3988 (15) |
C3—C4 | 1.4123 (14) | C3'—C4' | 1.4130 (15) |
C4—C5 | 1.4051 (14) | C4'—C5' | 1.4053 (14) |
C4—C9 | 1.4419 (14) | C4'—C9' | 1.4420 (15) |
C5—C6 | 1.3971 (14) | C5'—C6' | 1.3974 (15) |
C5—H5 | 0.9500 | C5'—H5' | 0.9500 |
C6—C7 | 1.4027 (15) | C6'—C7' | 1.3984 (16) |
C6—C1i | 1.5157 (14) | C6'—C1'ii | 1.5160 (16) |
C7—C8 | 1.3946 (15) | C7'—C8' | 1.3915 (16) |
C7—H7 | 0.9500 | C7'—H7' | 0.9500 |
C8—H8 | 0.9500 | C8'—H8' | 0.9500 |
C9—C10 | 1.1944 (16) | C9'—C10' | 1.1937 (16) |
C10—H10 | 0.957 (18) | C10'—H10' | 0.971 (19) |
C6i—C1—C2 | 113.00 (8) | C6'ii—C1'—C2' | 112.86 (9) |
C6i—C1—H1A | 109.0 | C6'ii—C1'—H1'1 | 109.0 |
C2—C1—H1A | 109.0 | C2'—C1'—H1'1 | 109.0 |
C6i—C1—H1B | 109.0 | C6'ii—C1'—H1'2 | 109.0 |
C2—C1—H1B | 109.0 | C2'—C1'—H1'2 | 109.0 |
H1A—C1—H1B | 107.8 | H1'1—C1'—H1'2 | 107.8 |
C3—C2—C1 | 112.38 (8) | C3'—C2'—C1' | 112.70 (9) |
C3—C2—H2A | 109.1 | C3'—C2'—H2'1 | 109.1 |
C1—C2—H2A | 109.1 | C1'—C2'—H2'1 | 109.1 |
C3—C2—H2B | 109.1 | C3'—C2'—H2'2 | 109.1 |
C1—C2—H2B | 109.1 | C1'—C2'—H2'2 | 109.1 |
H2A—C2—H2B | 107.9 | H2'1—C2'—H2'2 | 107.8 |
C8—C3—C4 | 117.16 (9) | C8'—C3'—C4' | 116.89 (10) |
C8—C3—C2 | 120.23 (9) | C8'—C3'—C2' | 120.63 (10) |
C4—C3—C2 | 121.24 (9) | C4'—C3'—C2' | 121.34 (10) |
C5—C4—C3 | 119.85 (9) | C5'—C4'—C3' | 119.87 (9) |
C5—C4—C9 | 118.38 (9) | C5'—C4'—C9' | 119.55 (9) |
C3—C4—C9 | 121.22 (9) | C3'—C4'—C9' | 120.11 (9) |
C6—C5—C4 | 120.98 (10) | C6'—C5'—C4' | 121.00 (10) |
C6—C5—H5 | 119.5 | C6'—C5'—H5' | 119.5 |
C4—C5—H5 | 119.5 | C4'—C5'—H5' | 119.5 |
C5—C6—C7 | 117.52 (9) | C5'—C6'—C7' | 117.09 (10) |
C5—C6—C1i | 119.93 (9) | C5'—C6'—C1'ii | 120.52 (10) |
C7—C6—C1i | 121.45 (9) | C7'—C6'—C1'ii | 121.15 (10) |
C8—C7—C6 | 120.22 (10) | C8'—C7'—C6' | 120.66 (10) |
C8—C7—H7 | 119.9 | C8'—C7'—H7' | 119.7 |
C6—C7—H7 | 119.9 | C6'—C7'—H7' | 119.7 |
C7—C8—C3 | 121.27 (10) | C7'—C8'—C3' | 121.18 (10) |
C7—C8—H8 | 119.4 | C7'—C8'—H8' | 119.4 |
C3—C8—H8 | 119.4 | C3'—C8'—H8' | 119.4 |
C10—C9—C4 | 178.10 (12) | C10'—C9'—C4' | 179.33 (12) |
C9—C10—H10 | 178.9 (11) | C9'—C10'—H10' | 179.0 (11) |
C6i—C1—C2—C3 | 0.37 (13) | C6'ii—C1'—C2'—C3' | −7.49 (14) |
C1—C2—C3—C8 | −83.73 (12) | C1'—C2'—C3'—C8' | 92.85 (12) |
C1—C2—C3—C4 | 82.56 (12) | C1'—C2'—C3'—C4' | −74.54 (13) |
C8—C3—C4—C5 | 13.75 (14) | C8'—C3'—C4'—C5' | −14.18 (14) |
C2—C3—C4—C5 | −152.94 (10) | C2'—C3'—C4'—C5' | 153.66 (10) |
C8—C3—C4—C9 | −174.87 (9) | C8'—C3'—C4'—C9' | 173.77 (9) |
C2—C3—C4—C9 | 18.44 (14) | C2'—C3'—C4'—C9' | −18.39 (15) |
C3—C4—C5—C6 | −0.07 (15) | C3'—C4'—C5'—C6' | −0.46 (15) |
C9—C4—C5—C6 | −171.69 (9) | C9'—C4'—C5'—C6' | 171.63 (9) |
C4—C5—C6—C7 | −13.95 (15) | C4'—C5'—C6'—C7' | 14.87 (15) |
C4—C5—C6—C1i | 154.25 (10) | C4'—C5'—C6'—C1'ii | −152.57 (10) |
C5—C6—C7—C8 | 14.20 (14) | C5'—C6'—C7'—C8' | −14.64 (15) |
C1i—C6—C7—C8 | −153.81 (10) | C1'ii—C6'—C7'—C8' | 152.71 (10) |
C6—C7—C8—C3 | −0.41 (15) | C6'—C7'—C8'—C3' | −0.11 (16) |
C4—C3—C8—C7 | −13.60 (15) | C4'—C3'—C8'—C7' | 14.55 (15) |
C2—C3—C8—C7 | 153.24 (10) | C2'—C3'—C8'—C7' | −153.38 (10) |
Symmetry codes: (i) −x, −y, −z+1; (ii) −x+1, −y+1, −z. |
C20H16 | Dx = 1.237 Mg m−3 |
Mr = 256.33 | Mo Kα radiation, λ = 0.71073 Å |
Trigonal, P31 | Cell parameters from 5139 reflections |
Hall symbol: P 31 | θ = 2–28° |
a = 11.8823 (12) Å | µ = 0.07 mm−1 |
c = 8.4426 (12) Å | T = 143 K |
V = 1032.3 (2) Å3 | Irregular tablet, colourless |
Z = 3 | 0.40 × 0.20 × 0.08 mm |
F(000) = 408 |
Bruker SMART 1000 CCD area-detector diffractometer | 1536 reflections with I > 2σ(I) |
Radiation source: fine-focus sealed tube | Rint = 0.081 |
Graphite monochromator | θmax = 28.3°, θmin = 2.0° |
Detector resolution: 8.192 pixels mm-1 | h = −15→15 |
ω scans | k = −15→15 |
13844 measured reflections | l = −11→11 |
1719 independent reflections |
Refinement on F2 | Primary atom site location: structure-invariant direct methods |
Least-squares matrix: full | Secondary atom site location: difference Fourier map |
R[F2 > 2σ(F2)] = 0.035 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.088 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.02 | w = 1/[σ2(Fo2) + (0.0585P)2 + 0.013P] where P = (Fo2 + 2Fc2)/3 |
1719 reflections | (Δ/σ)max < 0.001 |
189 parameters | Δρmax = 0.22 e Å−3 |
185 restraints | Δρmin = −0.14 e Å−3 |
C20H16 | Z = 3 |
Mr = 256.33 | Mo Kα radiation |
Trigonal, P31 | µ = 0.07 mm−1 |
a = 11.8823 (12) Å | T = 143 K |
c = 8.4426 (12) Å | 0.40 × 0.20 × 0.08 mm |
V = 1032.3 (2) Å3 |
Bruker SMART 1000 CCD area-detector diffractometer | 1536 reflections with I > 2σ(I) |
13844 measured reflections | Rint = 0.081 |
1719 independent reflections |
R[F2 > 2σ(F2)] = 0.035 | 185 restraints |
wR(F2) = 0.088 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.02 | Δρmax = 0.22 e Å−3 |
1719 reflections | Δρmin = −0.14 e Å−3 |
189 parameters |
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. The compound crystallizes by chance in a chiral space group. In the absence of significant anomalous scattering, Friedel opposite reflections were merged and the Flack parameter is thus meaningless. |
x | y | z | Uiso*/Ueq | ||
C1 | 0.38463 (19) | 0.52599 (19) | 0.2228 (2) | 0.0288 (4) | |
H1A | 0.4709 | 0.5625 | 0.1718 | 0.035* | |
H1B | 0.3651 | 0.5973 | 0.2359 | 0.035* | |
C2 | 0.27775 (19) | 0.41697 (19) | 0.1114 (2) | 0.0279 (4) | |
H2A | 0.2007 | 0.4282 | 0.1068 | 0.034* | |
H2B | 0.3130 | 0.4277 | 0.0028 | 0.034* | |
C3 | 0.23642 (18) | 0.28075 (17) | 0.1699 (2) | 0.0237 (4) | |
C4 | 0.32029 (19) | 0.22918 (18) | 0.1641 (2) | 0.0243 (4) | |
C5 | 0.30519 (18) | 0.13403 (18) | 0.2743 (2) | 0.0249 (4) | |
H5 | 0.3624 | 0.0999 | 0.2705 | 0.030* | |
C6 | 0.20789 (18) | 0.08875 (17) | 0.3890 (2) | 0.0245 (4) | |
C7 | 0.10905 (18) | 0.11972 (17) | 0.3691 (2) | 0.0244 (4) | |
H7 | 0.0317 | 0.0759 | 0.4301 | 0.029* | |
C8 | 0.12385 (17) | 0.21385 (18) | 0.2609 (2) | 0.0244 (4) | |
H8 | 0.0559 | 0.2333 | 0.2484 | 0.029* | |
C9 | 0.2258 (2) | 0.03632 (19) | 0.5445 (2) | 0.0298 (4) | |
H9A | 0.2845 | 0.0008 | 0.5278 | 0.036* | |
H9B | 0.1407 | −0.0358 | 0.5800 | 0.036* | |
C10 | 0.28428 (19) | 0.14386 (19) | 0.6790 (2) | 0.0276 (4) | |
H10A | 0.2150 | 0.1279 | 0.7560 | 0.033* | |
H10B | 0.3531 | 0.1366 | 0.7363 | 0.033* | |
C11 | 0.34088 (18) | 0.28007 (18) | 0.6133 (2) | 0.0236 (4) | |
C12 | 0.26351 (18) | 0.33750 (17) | 0.6053 (2) | 0.0228 (4) | |
H12 | 0.1938 | 0.3112 | 0.6781 | 0.027* | |
C13 | 0.28619 (18) | 0.43301 (17) | 0.4927 (2) | 0.0233 (4) | |
C14 | 0.38900 (19) | 0.47263 (17) | 0.3841 (2) | 0.0247 (4) | |
C15 | 0.48119 (17) | 0.43557 (18) | 0.4172 (2) | 0.0266 (4) | |
H15 | 0.5616 | 0.4761 | 0.3620 | 0.032* | |
C16 | 0.45747 (19) | 0.34053 (19) | 0.5294 (2) | 0.0276 (4) | |
H16 | 0.5214 | 0.3166 | 0.5490 | 0.033* | |
C17 | 0.43427 (19) | 0.28743 (19) | 0.0645 (2) | 0.0278 (4) | |
C18 | 0.5296 (2) | 0.3360 (2) | −0.0167 (3) | 0.0344 (4) | |
H18 | 0.611 (2) | 0.371 (2) | −0.100 (3) | 0.025 (5)* | |
C19 | 0.19045 (19) | 0.47211 (18) | 0.4727 (2) | 0.0261 (4) | |
C20 | 0.1076 (2) | 0.4989 (2) | 0.4533 (3) | 0.0318 (4) | |
H20 | 0.040 (3) | 0.516 (3) | 0.440 (3) | 0.049 (8)* |
U11 | U22 | U33 | U12 | U13 | U23 | |
C1 | 0.0319 (10) | 0.0230 (9) | 0.0280 (9) | 0.0110 (8) | −0.0003 (8) | 0.0027 (7) |
C2 | 0.0334 (10) | 0.0277 (10) | 0.0235 (9) | 0.0158 (8) | −0.0011 (8) | 0.0039 (7) |
C3 | 0.0268 (9) | 0.0232 (9) | 0.0183 (8) | 0.0104 (7) | −0.0047 (7) | −0.0035 (7) |
C4 | 0.0260 (9) | 0.0244 (9) | 0.0204 (8) | 0.0110 (7) | −0.0007 (7) | −0.0031 (7) |
C5 | 0.0254 (9) | 0.0227 (9) | 0.0269 (9) | 0.0122 (7) | −0.0025 (7) | −0.0045 (7) |
C6 | 0.0267 (9) | 0.0169 (8) | 0.0253 (9) | 0.0075 (7) | −0.0030 (7) | −0.0035 (6) |
C7 | 0.0238 (9) | 0.0196 (8) | 0.0230 (9) | 0.0057 (7) | 0.0000 (7) | −0.0045 (7) |
C8 | 0.0211 (8) | 0.0278 (9) | 0.0230 (8) | 0.0113 (8) | −0.0062 (7) | −0.0082 (7) |
C9 | 0.0363 (11) | 0.0213 (9) | 0.0304 (10) | 0.0134 (8) | −0.0009 (8) | 0.0024 (7) |
C10 | 0.0319 (10) | 0.0282 (9) | 0.0236 (9) | 0.0156 (8) | −0.0036 (7) | 0.0022 (7) |
C11 | 0.0255 (9) | 0.0225 (8) | 0.0215 (8) | 0.0108 (7) | −0.0073 (7) | −0.0027 (7) |
C12 | 0.0239 (8) | 0.0214 (8) | 0.0205 (8) | 0.0094 (7) | −0.0037 (7) | −0.0036 (7) |
C13 | 0.0259 (9) | 0.0193 (8) | 0.0219 (8) | 0.0092 (7) | −0.0056 (7) | −0.0040 (6) |
C14 | 0.0260 (9) | 0.0171 (8) | 0.0253 (9) | 0.0065 (7) | −0.0035 (7) | −0.0025 (7) |
C15 | 0.0198 (9) | 0.0237 (9) | 0.0292 (10) | 0.0056 (7) | −0.0013 (7) | −0.0040 (7) |
C16 | 0.0243 (9) | 0.0272 (9) | 0.0318 (10) | 0.0132 (8) | −0.0068 (7) | −0.0045 (8) |
C17 | 0.0292 (10) | 0.0283 (9) | 0.0275 (9) | 0.0156 (8) | −0.0012 (7) | −0.0019 (8) |
C18 | 0.0354 (11) | 0.0350 (10) | 0.0328 (10) | 0.0175 (9) | 0.0062 (9) | 0.0011 (8) |
C19 | 0.0321 (10) | 0.0232 (9) | 0.0227 (9) | 0.0135 (8) | −0.0009 (7) | −0.0011 (7) |
C20 | 0.0385 (11) | 0.0320 (10) | 0.0318 (10) | 0.0227 (9) | 0.0019 (8) | 0.0033 (8) |
C1—C14 | 1.514 (3) | C9—H9A | 0.9900 |
C1—C2 | 1.591 (3) | C9—H9B | 0.9900 |
C1—H1A | 0.9900 | C10—C11 | 1.514 (3) |
C1—H1B | 0.9900 | C10—H10A | 0.9900 |
C2—C3 | 1.520 (3) | C10—H10B | 0.9900 |
C2—H2A | 0.9900 | C11—C16 | 1.394 (3) |
C2—H2B | 0.9900 | C11—C12 | 1.394 (3) |
C3—C8 | 1.396 (3) | C12—C13 | 1.400 (3) |
C3—C4 | 1.408 (3) | C12—H12 | 0.9500 |
C4—C5 | 1.405 (3) | C13—C14 | 1.407 (3) |
C4—C17 | 1.443 (3) | C13—C19 | 1.438 (3) |
C5—C6 | 1.393 (3) | C14—C15 | 1.398 (3) |
C5—H5 | 0.9500 | C15—C16 | 1.390 (3) |
C6—C7 | 1.405 (3) | C15—H15 | 0.9500 |
C6—C9 | 1.513 (3) | C16—H16 | 0.9500 |
C7—C8 | 1.385 (3) | C17—C18 | 1.197 (3) |
C7—H7 | 0.9500 | C18—H18 | 1.09 (2) |
C8—H8 | 0.9500 | C19—C20 | 1.188 (3) |
C9—C10 | 1.587 (3) | C20—H20 | 0.93 (3) |
C14—C1—C2 | 111.79 (15) | C10—C9—H9A | 109.1 |
C14—C1—H1A | 109.3 | C6—C9—H9B | 109.1 |
C2—C1—H1A | 109.3 | C10—C9—H9B | 109.1 |
C14—C1—H1B | 109.3 | H9A—C9—H9B | 107.8 |
C2—C1—H1B | 109.3 | C11—C10—C9 | 112.32 (16) |
H1A—C1—H1B | 107.9 | C11—C10—H10A | 109.1 |
C3—C2—C1 | 112.12 (15) | C9—C10—H10A | 109.1 |
C3—C2—H2A | 109.2 | C11—C10—H10B | 109.1 |
C1—C2—H2A | 109.2 | C9—C10—H10B | 109.1 |
C3—C2—H2B | 109.2 | H10A—C10—H10B | 107.9 |
C1—C2—H2B | 109.2 | C16—C11—C12 | 116.89 (17) |
H2A—C2—H2B | 107.9 | C16—C11—C10 | 122.23 (17) |
C8—C3—C4 | 117.17 (17) | C12—C11—C10 | 119.46 (17) |
C8—C3—C2 | 119.51 (17) | C11—C12—C13 | 121.53 (17) |
C4—C3—C2 | 122.02 (17) | C11—C12—H12 | 119.2 |
C5—C4—C3 | 119.61 (17) | C13—C12—H12 | 119.2 |
C5—C4—C17 | 118.91 (17) | C12—C13—C14 | 119.81 (17) |
C3—C4—C17 | 120.68 (17) | C12—C13—C19 | 118.64 (17) |
C6—C5—C4 | 121.23 (17) | C14—C13—C19 | 120.66 (17) |
C6—C5—H5 | 119.4 | C15—C14—C13 | 116.74 (17) |
C4—C5—H5 | 119.4 | C15—C14—C1 | 120.55 (18) |
C5—C6—C7 | 117.16 (17) | C13—C14—C1 | 121.37 (17) |
C5—C6—C9 | 120.12 (17) | C16—C15—C14 | 121.31 (17) |
C7—C6—C9 | 121.29 (17) | C16—C15—H15 | 119.3 |
C8—C7—C6 | 120.32 (17) | C14—C15—H15 | 119.3 |
C8—C7—H7 | 119.8 | C15—C16—C11 | 120.69 (17) |
C6—C7—H7 | 119.8 | C15—C16—H16 | 119.7 |
C7—C8—C3 | 121.42 (17) | C11—C16—H16 | 119.7 |
C7—C8—H8 | 119.3 | C18—C17—C4 | 179.3 (2) |
C3—C8—H8 | 119.3 | C17—C18—H18 | 173.4 (12) |
C6—C9—C10 | 112.64 (15) | C20—C19—C13 | 177.0 (2) |
C6—C9—H9A | 109.1 | C19—C20—H20 | 177.2 (18) |
C14—C1—C2—C3 | −18.1 (2) | C6—C9—C10—C11 | −14.7 (2) |
C1—C2—C3—C8 | 97.2 (2) | C9—C10—C11—C16 | −73.0 (2) |
C1—C2—C3—C4 | −69.5 (2) | C9—C10—C11—C12 | 93.0 (2) |
C8—C3—C4—C5 | −14.5 (3) | C16—C11—C12—C13 | 13.7 (3) |
C2—C3—C4—C5 | 152.45 (17) | C10—C11—C12—C13 | −153.03 (18) |
C8—C3—C4—C17 | 175.86 (17) | C11—C12—C13—C14 | 0.2 (3) |
C2—C3—C4—C17 | −17.2 (3) | C11—C12—C13—C19 | 169.42 (17) |
C3—C4—C5—C6 | 0.5 (3) | C12—C13—C14—C15 | −14.1 (3) |
C17—C4—C5—C6 | 170.32 (17) | C19—C13—C14—C15 | 176.86 (16) |
C4—C5—C6—C7 | 13.6 (3) | C12—C13—C14—C1 | 152.79 (17) |
C4—C5—C6—C9 | −152.86 (18) | C19—C13—C14—C1 | −16.3 (3) |
C5—C6—C7—C8 | −13.7 (2) | C2—C1—C14—C15 | 97.6 (2) |
C9—C6—C7—C8 | 152.61 (17) | C2—C1—C14—C13 | −68.8 (2) |
C6—C7—C8—C3 | −0.4 (3) | C13—C14—C15—C16 | 14.4 (3) |
C4—C3—C8—C7 | 14.5 (3) | C1—C14—C15—C16 | −152.59 (19) |
C2—C3—C8—C7 | −152.73 (17) | C14—C15—C16—C11 | −0.6 (3) |
C5—C6—C9—C10 | 93.5 (2) | C12—C11—C16—C15 | −13.5 (3) |
C7—C6—C9—C10 | −72.4 (2) | C10—C11—C16—C15 | 152.85 (18) |
C20H16 | F(000) = 272 |
Mr = 256.33 | Dx = 1.220 Mg m−3 |
Monoclinic, P21 | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: P 2yb | Cell parameters from 4465 reflections |
a = 7.6187 (10) Å | θ = 2–28° |
b = 10.8231 (16) Å | µ = 0.07 mm−1 |
c = 8.6293 (12) Å | T = 143 K |
β = 101.230 (6)° | Irregular prism, colourless |
V = 697.93 (17) Å3 | 0.40 × 0.20 × 0.18 mm |
Z = 2 |
Bruker SMART 1000 CCD area-detector diffractometer | 1706 reflections with I > 2σ(I) |
Radiation source: fine-focus sealed tube | Rint = 0.049 |
Graphite monochromator | θmax = 28.3°, θmin = 2.4° |
Detector resolution: 8.192 pixels mm-1 | h = −10→10 |
ω scans | k = −14→14 |
7442 measured reflections | l = −11→11 |
1821 independent reflections |
Refinement on F2 | Primary atom site location: structure-invariant direct methods |
Least-squares matrix: full | Secondary atom site location: difference Fourier map |
R[F2 > 2σ(F2)] = 0.036 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.098 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.07 | w = 1/[σ2(Fo2) + (0.071P)2 + 0.0161P] where P = (Fo2 + 2Fc2)/3 |
1821 reflections | (Δ/σ)max < 0.001 |
189 parameters | Δρmax = 0.26 e Å−3 |
185 restraints | Δρmin = −0.16 e Å−3 |
C20H16 | V = 697.93 (17) Å3 |
Mr = 256.33 | Z = 2 |
Monoclinic, P21 | Mo Kα radiation |
a = 7.6187 (10) Å | µ = 0.07 mm−1 |
b = 10.8231 (16) Å | T = 143 K |
c = 8.6293 (12) Å | 0.40 × 0.20 × 0.18 mm |
β = 101.230 (6)° |
Bruker SMART 1000 CCD area-detector diffractometer | 1706 reflections with I > 2σ(I) |
7442 measured reflections | Rint = 0.049 |
1821 independent reflections |
R[F2 > 2σ(F2)] = 0.036 | 185 restraints |
wR(F2) = 0.098 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.07 | Δρmax = 0.26 e Å−3 |
1821 reflections | Δρmin = −0.16 e Å−3 |
189 parameters |
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. The compound crystallizes by chance in a chiral space group. In the absence of significant anomalous scattering, Friedel opposites were merged and the Flack parameter is thus meaningless. |
x | y | z | Uiso*/Ueq | ||
C1 | −0.0018 (2) | 0.37404 (17) | 0.7711 (2) | 0.0277 (3) | |
H1A | −0.0379 | 0.3161 | 0.8480 | 0.033* | |
H1B | −0.0983 | 0.4359 | 0.7422 | 0.033* | |
C2 | 0.1770 (2) | 0.44218 (17) | 0.8517 (2) | 0.0289 (4) | |
H2A | 0.1464 | 0.5225 | 0.8944 | 0.035* | |
H2B | 0.2395 | 0.3917 | 0.9413 | 0.035* | |
C3 | 0.3022 (2) | 0.46428 (15) | 0.73761 (18) | 0.0228 (3) | |
C4 | 0.4525 (2) | 0.38759 (15) | 0.73720 (17) | 0.0222 (3) | |
C5 | 0.51507 (19) | 0.36971 (16) | 0.59655 (18) | 0.0235 (3) | |
H5 | 0.6154 | 0.3176 | 0.5966 | 0.028* | |
C6 | 0.4328 (2) | 0.42705 (16) | 0.45668 (18) | 0.0253 (3) | |
C7 | 0.3143 (2) | 0.52349 (16) | 0.4689 (2) | 0.0274 (3) | |
H7 | 0.2771 | 0.5772 | 0.3815 | 0.033* | |
C8 | 0.2501 (2) | 0.54185 (15) | 0.6075 (2) | 0.0266 (3) | |
H8 | 0.1698 | 0.6080 | 0.6137 | 0.032* | |
C9 | 0.4407 (2) | 0.3700 (2) | 0.2981 (2) | 0.0322 (4) | |
H9A | 0.5666 | 0.3496 | 0.2945 | 0.039* | |
H9B | 0.3980 | 0.4310 | 0.2136 | 0.039* | |
C10 | 0.3231 (2) | 0.24869 (18) | 0.26524 (19) | 0.0288 (3) | |
H10A | 0.2624 | 0.2472 | 0.1528 | 0.035* | |
H10B | 0.4021 | 0.1754 | 0.2849 | 0.035* | |
C11 | 0.18376 (19) | 0.24126 (16) | 0.36865 (18) | 0.0226 (3) | |
C12 | 0.0380 (2) | 0.32237 (16) | 0.34748 (19) | 0.0250 (3) | |
H12 | −0.0078 | 0.3560 | 0.2460 | 0.030* | |
C13 | −0.0398 (2) | 0.35376 (14) | 0.4754 (2) | 0.0248 (3) | |
H13 | −0.1358 | 0.4113 | 0.4604 | 0.030* | |
C14 | 0.0197 (2) | 0.30306 (15) | 0.62436 (19) | 0.0229 (3) | |
C15 | 0.1327 (2) | 0.19907 (14) | 0.63414 (18) | 0.0220 (3) | |
C16 | 0.2166 (2) | 0.17150 (14) | 0.50695 (19) | 0.0220 (3) | |
H16 | 0.2973 | 0.1039 | 0.5155 | 0.026* | |
C17 | 0.5339 (2) | 0.31673 (17) | 0.87298 (19) | 0.0254 (3) | |
C18 | 0.6094 (3) | 0.2580 (2) | 0.9827 (2) | 0.0352 (4) | |
H18 | 0.667 (3) | 0.211 (3) | 1.070 (3) | 0.063 (8)* | |
C19 | 0.1768 (2) | 0.12835 (16) | 0.77758 (19) | 0.0272 (3) | |
C20 | 0.2099 (3) | 0.06603 (19) | 0.8933 (2) | 0.0373 (4) | |
H20 | 0.234 (3) | 0.008 (3) | 0.980 (3) | 0.054 (7)* |
U11 | U22 | U33 | U12 | U13 | U23 | |
C1 | 0.0234 (7) | 0.0275 (8) | 0.0340 (8) | −0.0019 (7) | 0.0103 (6) | −0.0044 (7) |
C2 | 0.0244 (7) | 0.0343 (9) | 0.0284 (8) | −0.0004 (7) | 0.0064 (6) | −0.0080 (7) |
C3 | 0.0207 (6) | 0.0206 (7) | 0.0257 (7) | −0.0033 (6) | 0.0013 (5) | −0.0051 (6) |
C4 | 0.0186 (6) | 0.0231 (7) | 0.0238 (7) | −0.0045 (6) | 0.0016 (5) | −0.0030 (6) |
C5 | 0.0175 (6) | 0.0262 (8) | 0.0273 (7) | −0.0036 (6) | 0.0054 (5) | −0.0024 (7) |
C6 | 0.0218 (7) | 0.0285 (8) | 0.0263 (7) | −0.0091 (6) | 0.0065 (6) | −0.0009 (6) |
C7 | 0.0258 (8) | 0.0249 (8) | 0.0292 (8) | −0.0062 (6) | −0.0006 (6) | 0.0056 (7) |
C8 | 0.0218 (7) | 0.0207 (7) | 0.0352 (8) | −0.0024 (6) | 0.0001 (6) | −0.0031 (6) |
C9 | 0.0314 (8) | 0.0420 (10) | 0.0248 (7) | −0.0106 (8) | 0.0093 (6) | −0.0015 (7) |
C10 | 0.0299 (8) | 0.0321 (8) | 0.0254 (7) | −0.0025 (7) | 0.0075 (6) | −0.0018 (7) |
C11 | 0.0205 (6) | 0.0215 (7) | 0.0254 (7) | −0.0027 (6) | 0.0034 (5) | −0.0026 (6) |
C12 | 0.0225 (7) | 0.0225 (7) | 0.0278 (7) | −0.0035 (6) | −0.0005 (6) | 0.0020 (6) |
C13 | 0.0174 (7) | 0.0187 (7) | 0.0369 (8) | −0.0012 (5) | 0.0018 (6) | −0.0012 (6) |
C14 | 0.0175 (6) | 0.0205 (7) | 0.0313 (8) | −0.0041 (6) | 0.0062 (6) | −0.0030 (6) |
C15 | 0.0196 (6) | 0.0187 (7) | 0.0268 (7) | −0.0038 (6) | 0.0022 (6) | −0.0001 (6) |
C16 | 0.0195 (6) | 0.0165 (6) | 0.0291 (7) | −0.0010 (5) | 0.0025 (5) | −0.0021 (6) |
C17 | 0.0235 (7) | 0.0260 (8) | 0.0264 (7) | −0.0016 (6) | 0.0046 (6) | −0.0032 (6) |
C18 | 0.0355 (9) | 0.0386 (10) | 0.0310 (9) | 0.0072 (8) | 0.0056 (7) | 0.0044 (8) |
C19 | 0.0283 (8) | 0.0224 (8) | 0.0307 (8) | −0.0035 (6) | 0.0049 (6) | −0.0025 (6) |
C20 | 0.0480 (11) | 0.0298 (9) | 0.0316 (9) | −0.0043 (8) | 0.0015 (8) | 0.0033 (7) |
C1—C14 | 1.517 (2) | C9—H9A | 0.9900 |
C1—C2 | 1.586 (2) | C9—H9B | 0.9900 |
C1—H1A | 0.9900 | C10—C11 | 1.516 (2) |
C1—H1B | 0.9900 | C10—H10A | 0.9900 |
C2—C3 | 1.517 (2) | C10—H10B | 0.9900 |
C2—H2A | 0.9900 | C11—C16 | 1.393 (2) |
C2—H2B | 0.9900 | C11—C12 | 1.399 (2) |
C3—C8 | 1.396 (2) | C12—C13 | 1.393 (2) |
C3—C4 | 1.415 (2) | C12—H12 | 0.9500 |
C4—C5 | 1.401 (2) | C13—C14 | 1.390 (2) |
C4—C17 | 1.436 (2) | C13—H13 | 0.9500 |
C5—C6 | 1.393 (2) | C14—C15 | 1.410 (2) |
C5—H5 | 0.9500 | C15—C16 | 1.405 (2) |
C6—C7 | 1.397 (3) | C15—C19 | 1.438 (2) |
C6—C9 | 1.514 (2) | C16—H16 | 0.9500 |
C7—C8 | 1.392 (3) | C17—C18 | 1.191 (3) |
C7—H7 | 0.9500 | C18—H18 | 0.95 (3) |
C8—H8 | 0.9500 | C19—C20 | 1.191 (3) |
C9—C10 | 1.584 (3) | C20—H20 | 0.96 (3) |
C14—C1—C2 | 112.24 (12) | C10—C9—H9A | 109.1 |
C14—C1—H1A | 109.2 | C6—C9—H9B | 109.1 |
C2—C1—H1A | 109.2 | C10—C9—H9B | 109.1 |
C14—C1—H1B | 109.2 | H9A—C9—H9B | 107.9 |
C2—C1—H1B | 109.2 | C11—C10—C9 | 112.05 (14) |
H1A—C1—H1B | 107.9 | C11—C10—H10A | 109.2 |
C3—C2—C1 | 112.56 (13) | C9—C10—H10A | 109.2 |
C3—C2—H2A | 109.1 | C11—C10—H10B | 109.2 |
C1—C2—H2A | 109.1 | C9—C10—H10B | 109.2 |
C3—C2—H2B | 109.1 | H10A—C10—H10B | 107.9 |
C1—C2—H2B | 109.1 | C16—C11—C12 | 117.22 (14) |
H2A—C2—H2B | 107.8 | C16—C11—C10 | 120.24 (14) |
C8—C3—C4 | 117.01 (14) | C12—C11—C10 | 121.24 (15) |
C8—C3—C2 | 120.04 (14) | C13—C12—C11 | 119.93 (14) |
C4—C3—C2 | 121.36 (14) | C13—C12—H12 | 120.0 |
C5—C4—C3 | 119.69 (14) | C11—C12—H12 | 120.0 |
C5—C4—C17 | 117.85 (14) | C14—C13—C12 | 121.62 (15) |
C3—C4—C17 | 122.17 (14) | C14—C13—H13 | 119.2 |
C6—C5—C4 | 121.16 (14) | C12—C13—H13 | 119.2 |
C6—C5—H5 | 119.4 | C13—C14—C15 | 117.12 (14) |
C4—C5—H5 | 119.4 | C13—C14—C1 | 120.23 (15) |
C5—C6—C7 | 117.12 (14) | C15—C14—C1 | 121.21 (14) |
C5—C6—C9 | 120.75 (16) | C16—C15—C14 | 119.21 (14) |
C7—C6—C9 | 120.87 (15) | C16—C15—C19 | 119.58 (14) |
C8—C7—C6 | 120.78 (15) | C14—C15—C19 | 120.93 (14) |
C8—C7—H7 | 119.6 | C11—C16—C15 | 121.40 (14) |
C6—C7—H7 | 119.6 | C11—C16—H16 | 119.3 |
C7—C8—C3 | 120.85 (15) | C15—C16—H16 | 119.3 |
C7—C8—H8 | 119.6 | C18—C17—C4 | 176.63 (17) |
C3—C8—H8 | 119.6 | C17—C18—H18 | 178.6 (17) |
C6—C9—C10 | 112.28 (13) | C20—C19—C15 | 177.47 (18) |
C6—C9—H9A | 109.1 | C19—C20—H20 | 174.0 (17) |
C14—C1—C2—C3 | 22.3 (2) | C6—C9—C10—C11 | 19.4 (2) |
C1—C2—C3—C8 | 64.0 (2) | C9—C10—C11—C16 | −97.61 (19) |
C1—C2—C3—C4 | −101.20 (18) | C9—C10—C11—C12 | 69.0 (2) |
C8—C3—C4—C5 | −15.2 (2) | C16—C11—C12—C13 | 15.7 (2) |
C2—C3—C4—C5 | 150.48 (15) | C10—C11—C12—C13 | −151.23 (16) |
C8—C3—C4—C17 | 171.22 (14) | C11—C12—C13—C14 | −2.3 (2) |
C2—C3—C4—C17 | −23.2 (2) | C12—C13—C14—C15 | −13.9 (2) |
C3—C4—C5—C6 | 0.6 (2) | C12—C13—C14—C1 | 152.54 (15) |
C17—C4—C5—C6 | 174.47 (15) | C2—C1—C14—C13 | −99.26 (17) |
C4—C5—C6—C7 | 14.3 (2) | C2—C1—C14—C15 | 66.7 (2) |
C4—C5—C6—C9 | −153.02 (15) | C13—C14—C15—C16 | 16.4 (2) |
C5—C6—C7—C8 | −14.6 (2) | C1—C14—C15—C16 | −149.91 (15) |
C9—C6—C7—C8 | 152.71 (16) | C13—C14—C15—C19 | −169.66 (14) |
C6—C7—C8—C3 | −0.1 (2) | C1—C14—C15—C19 | 24.0 (2) |
C4—C3—C8—C7 | 15.0 (2) | C12—C11—C16—C15 | −13.1 (2) |
C2—C3—C8—C7 | −150.84 (16) | C10—C11—C16—C15 | 154.03 (15) |
C5—C6—C9—C10 | 70.55 (19) | C14—C15—C16—C11 | −3.1 (2) |
C7—C6—C9—C10 | −96.3 (2) | C19—C15—C16—C11 | −177.07 (14) |
C20H16 | Dx = 1.190 Mg m−3 |
Mr = 256.33 | Mo Kα radiation, λ = 0.71073 Å |
Trigonal, P31 | Cell parameters from 5471 reflections |
Hall symbol: P 31 | θ = 2–28° |
a = 12.5475 (12) Å | µ = 0.07 mm−1 |
c = 7.8705 (10) Å | T = 143 K |
V = 1073.1 (2) Å3 | Needle, colourless |
Z = 3 | 0.45 × 0.12 × 0.11 mm |
F(000) = 408 |
Bruker SMART 1000 CCD area-detector diffractometer | 1311 reflections with I > 2σ(I) |
Radiation source: fine-focus sealed tube | Rint = 0.037 |
Graphite monochromator | θmax = 26.4°, θmin = 1.9° |
Detector resolution: 8.192 pixels mm-1 | h = −15→15 |
ω scans | k = −15→15 |
14432 measured reflections | l = −9→9 |
1462 independent reflections |
Refinement on F2 | Primary atom site location: structure-invariant direct methods |
Least-squares matrix: full | Secondary atom site location: difference Fourier map |
R[F2 > 2σ(F2)] = 0.037 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.101 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.05 | w = 1/[σ2(Fo2) + (0.0692P)2 + 0.073P] where P = (Fo2 + 2Fc2)/3 |
1462 reflections | (Δ/σ)max < 0.001 |
189 parameters | Δρmax = 0.27 e Å−3 |
185 restraints | Δρmin = −0.12 e Å−3 |
C20H16 | Z = 3 |
Mr = 256.33 | Mo Kα radiation |
Trigonal, P31 | µ = 0.07 mm−1 |
a = 12.5475 (12) Å | T = 143 K |
c = 7.8705 (10) Å | 0.45 × 0.12 × 0.11 mm |
V = 1073.1 (2) Å3 |
Bruker SMART 1000 CCD area-detector diffractometer | 1311 reflections with I > 2σ(I) |
14432 measured reflections | Rint = 0.037 |
1462 independent reflections |
R[F2 > 2σ(F2)] = 0.037 | 185 restraints |
wR(F2) = 0.101 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.05 | Δρmax = 0.27 e Å−3 |
1462 reflections | Δρmin = −0.12 e Å−3 |
189 parameters |
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. The compound crystallizes by chance in a chiral space group. In the absence of significant anomalous scattering, the Friedel opposite reflections were merged and the Flack parameter is thus meaningless. |
x | y | z | Uiso*/Ueq | ||
C1 | 0.4525 (2) | 0.5701 (3) | 0.5217 (4) | 0.0467 (6) | |
H1A | 0.4192 | 0.5464 | 0.4052 | 0.051* | |
H1B | 0.4136 | 0.6137 | 0.5749 | 0.051* | |
C2 | 0.4176 (2) | 0.4496 (3) | 0.6277 (3) | 0.0431 (6) | |
H2A | 0.3469 | 0.4308 | 0.7026 | 0.047* | |
H2B | 0.3918 | 0.3795 | 0.5486 | 0.047* | |
C3 | 0.5241 (2) | 0.4632 (2) | 0.7351 (3) | 0.0336 (5) | |
C4 | 0.5642 (2) | 0.5382 (2) | 0.8805 (3) | 0.0331 (5) | |
C5 | 0.6870 (2) | 0.5902 (2) | 0.9345 (3) | 0.0313 (5) | |
H5 | 0.7140 | 0.6421 | 1.0316 | 0.038* | |
C6 | 0.7692 (2) | 0.5667 (2) | 0.8477 (3) | 0.0301 (5) | |
C7 | 0.7199 (2) | 0.4704 (2) | 0.7300 (3) | 0.0323 (5) | |
H7 | 0.7692 | 0.4385 | 0.6879 | 0.039* | |
C8 | 0.6002 (2) | 0.4214 (2) | 0.6745 (3) | 0.0352 (5) | |
H8 | 0.5691 | 0.3573 | 0.5926 | 0.042* | |
C9 | 0.9052 (2) | 0.6605 (2) | 0.8497 (3) | 0.0378 (5) | |
H9A | 0.9527 | 0.6169 | 0.8528 | 0.042* | |
H9B | 0.9247 | 0.7108 | 0.9542 | 0.042* | |
C10 | 0.9464 (2) | 0.7486 (2) | 0.6886 (3) | 0.0381 (5) | |
H10A | 1.0049 | 0.8339 | 0.7252 | 0.042* | |
H10B | 0.9899 | 0.7231 | 0.6078 | 0.042* | |
C11 | 0.8386 (2) | 0.7465 (2) | 0.5988 (3) | 0.0312 (5) | |
C12 | 0.7865 (2) | 0.6723 (2) | 0.4560 (3) | 0.0350 (5) | |
H12 | 0.8357 | 0.6518 | 0.3870 | 0.042* | |
C13 | 0.6651 (2) | 0.6282 (2) | 0.4130 (3) | 0.0391 (6) | |
H13 | 0.6319 | 0.5780 | 0.3151 | 0.047* | |
C14 | 0.5907 (2) | 0.6567 (2) | 0.5119 (3) | 0.0375 (5) | |
C15 | 0.6488 (2) | 0.7514 (2) | 0.6291 (3) | 0.0377 (6) | |
H15 | 0.6040 | 0.7859 | 0.6794 | 0.045* | |
C16 | 0.7723 (2) | 0.7972 (2) | 0.6747 (3) | 0.0341 (5) | |
C17 | 0.4861 (2) | 0.5759 (3) | 0.9650 (3) | 0.0422 (6) | |
C18 | 0.4248 (3) | 0.6080 (3) | 1.0396 (4) | 0.0646 (10) | |
H18 | 0.355 (4) | 0.612 (4) | 1.109 (5) | 0.094 (12)* | |
C19 | 0.8233 (2) | 0.8801 (2) | 0.8144 (3) | 0.0420 (6) | |
C20 | 0.8666 (3) | 0.9478 (3) | 0.9312 (4) | 0.0577 (8) | |
H20 | 0.904 (3) | 1.000 (4) | 1.028 (5) | 0.071 (11)* |
U11 | U22 | U33 | U12 | U13 | U23 | |
C1 | 0.0376 (13) | 0.0564 (16) | 0.0467 (14) | 0.0240 (12) | −0.0007 (11) | 0.0151 (12) |
C2 | 0.0344 (13) | 0.0431 (15) | 0.0456 (13) | 0.0149 (11) | −0.0019 (11) | 0.0074 (11) |
C3 | 0.0298 (11) | 0.0316 (12) | 0.0338 (10) | 0.0113 (10) | 0.0034 (9) | 0.0111 (9) |
C4 | 0.0361 (12) | 0.0348 (12) | 0.0337 (11) | 0.0217 (10) | 0.0112 (9) | 0.0148 (9) |
C5 | 0.0414 (13) | 0.0333 (12) | 0.0259 (9) | 0.0238 (11) | 0.0030 (8) | 0.0038 (8) |
C6 | 0.0335 (12) | 0.0323 (11) | 0.0282 (10) | 0.0192 (10) | 0.0044 (8) | 0.0078 (9) |
C7 | 0.0396 (12) | 0.0320 (11) | 0.0301 (10) | 0.0217 (10) | 0.0091 (9) | 0.0064 (9) |
C8 | 0.0421 (13) | 0.0274 (11) | 0.0296 (11) | 0.0126 (10) | 0.0036 (9) | 0.0036 (9) |
C9 | 0.0341 (12) | 0.0424 (13) | 0.0398 (12) | 0.0213 (11) | −0.0014 (9) | 0.0011 (10) |
C10 | 0.0311 (12) | 0.0357 (13) | 0.0449 (13) | 0.0147 (10) | 0.0054 (10) | 0.0006 (10) |
C11 | 0.0311 (11) | 0.0270 (11) | 0.0339 (10) | 0.0134 (9) | 0.0076 (9) | 0.0081 (9) |
C12 | 0.0393 (13) | 0.0345 (12) | 0.0296 (10) | 0.0173 (10) | 0.0115 (9) | 0.0081 (9) |
C13 | 0.0440 (14) | 0.0392 (13) | 0.0281 (10) | 0.0163 (11) | 0.0032 (10) | 0.0078 (10) |
C14 | 0.0386 (13) | 0.0434 (13) | 0.0325 (11) | 0.0221 (11) | 0.0017 (9) | 0.0146 (10) |
C15 | 0.0423 (13) | 0.0397 (13) | 0.0412 (12) | 0.0280 (11) | 0.0108 (10) | 0.0149 (10) |
C16 | 0.0401 (12) | 0.0275 (11) | 0.0362 (11) | 0.0181 (10) | 0.0081 (9) | 0.0082 (9) |
C17 | 0.0484 (15) | 0.0516 (15) | 0.0367 (12) | 0.0325 (13) | 0.0105 (10) | 0.0133 (11) |
C18 | 0.078 (2) | 0.100 (3) | 0.0531 (17) | 0.072 (2) | 0.0279 (16) | 0.0266 (17) |
C19 | 0.0469 (14) | 0.0327 (13) | 0.0518 (14) | 0.0238 (12) | 0.0066 (11) | −0.0003 (11) |
C20 | 0.0678 (19) | 0.0527 (17) | 0.0627 (18) | 0.0378 (16) | −0.0050 (16) | −0.0181 (15) |
C1—C14 | 1.520 (3) | C9—H9A | 0.9900 |
C1—C2 | 1.585 (4) | C9—H9B | 0.9900 |
C1—H1A | 0.9900 | C10—C11 | 1.515 (3) |
C1—H1B | 0.9900 | C10—H10A | 0.9900 |
C2—C3 | 1.518 (3) | C10—H10B | 0.9900 |
C2—H2A | 0.9900 | C11—C12 | 1.396 (3) |
C2—H2B | 0.9900 | C11—C16 | 1.408 (3) |
C3—C8 | 1.383 (3) | C12—C13 | 1.377 (4) |
C3—C4 | 1.405 (3) | C12—H12 | 0.9500 |
C4—C5 | 1.406 (3) | C13—C14 | 1.392 (4) |
C4—C17 | 1.446 (3) | C13—H13 | 0.9500 |
C5—C6 | 1.386 (3) | C14—C15 | 1.388 (4) |
C5—H5 | 0.9500 | C15—C16 | 1.404 (4) |
C6—C7 | 1.397 (3) | C15—H15 | 0.9500 |
C6—C9 | 1.513 (3) | C16—C19 | 1.427 (4) |
C7—C8 | 1.379 (3) | C17—C18 | 1.187 (4) |
C7—H7 | 0.9500 | C18—H18 | 1.06 (4) |
C8—H8 | 0.9500 | C19—C20 | 1.183 (4) |
C9—C10 | 1.590 (3) | C20—H20 | 0.96 (4) |
C14—C1—C2 | 112.44 (19) | C10—C9—H9A | 109.1 |
C14—C1—H1A | 109.1 | C6—C9—H9B | 109.1 |
C2—C1—H1A | 109.1 | C10—C9—H9B | 109.1 |
C14—C1—H1B | 109.1 | H9A—C9—H9B | 107.9 |
C2—C1—H1B | 109.1 | C11—C10—C9 | 112.52 (19) |
H1A—C1—H1B | 107.8 | C11—C10—H10A | 109.1 |
C3—C2—C1 | 112.2 (2) | C9—C10—H10A | 109.1 |
C3—C2—H2A | 109.2 | C11—C10—H10B | 109.1 |
C1—C2—H2A | 109.2 | C9—C10—H10B | 109.1 |
C3—C2—H2B | 109.2 | H10A—C10—H10B | 107.8 |
C1—C2—H2B | 109.2 | C12—C11—C16 | 117.2 (2) |
H2A—C2—H2B | 107.9 | C12—C11—C10 | 120.2 (2) |
C8—C3—C4 | 116.8 (2) | C16—C11—C10 | 121.2 (2) |
C8—C3—C2 | 120.1 (2) | C13—C12—C11 | 121.4 (2) |
C4—C3—C2 | 121.9 (2) | C13—C12—H12 | 119.3 |
C3—C4—C5 | 119.9 (2) | C11—C12—H12 | 119.3 |
C3—C4—C17 | 121.4 (2) | C12—C13—C14 | 120.5 (2) |
C5—C4—C17 | 118.3 (2) | C12—C13—H13 | 119.7 |
C6—C5—C4 | 120.8 (2) | C14—C13—H13 | 119.7 |
C6—C5—H5 | 119.6 | C15—C14—C13 | 117.3 (2) |
C4—C5—H5 | 119.6 | C15—C14—C1 | 120.1 (2) |
C5—C6—C7 | 117.1 (2) | C13—C14—C1 | 121.1 (2) |
C5—C6—C9 | 120.0 (2) | C14—C15—C16 | 121.3 (2) |
C7—C6—C9 | 121.24 (19) | C14—C15—H15 | 119.3 |
C8—C7—C6 | 120.5 (2) | C16—C15—H15 | 119.3 |
C8—C7—H7 | 119.7 | C15—C16—C11 | 119.2 (2) |
C6—C7—H7 | 119.7 | C15—C16—C19 | 119.8 (2) |
C7—C8—C3 | 121.7 (2) | C11—C16—C19 | 120.3 (2) |
C7—C8—H8 | 119.1 | C18—C17—C4 | 177.6 (3) |
C3—C8—H8 | 119.1 | C17—C18—H18 | 165 (2) |
C6—C9—C10 | 112.38 (19) | C20—C19—C16 | 178.8 (3) |
C6—C9—H9A | 109.1 | C19—C20—H20 | 176 (2) |
C14—C1—C2—C3 | 16.1 (3) | C6—C9—C10—C11 | 17.5 (3) |
C1—C2—C3—C8 | −95.5 (3) | C9—C10—C11—C12 | −97.5 (2) |
C1—C2—C3—C4 | 71.8 (3) | C9—C10—C11—C16 | 69.0 (3) |
C8—C3—C4—C5 | 14.4 (3) | C16—C11—C12—C13 | −13.9 (3) |
C2—C3—C4—C5 | −153.2 (2) | C10—C11—C12—C13 | 153.1 (2) |
C8—C3—C4—C17 | −173.2 (2) | C11—C12—C13—C14 | −0.1 (3) |
C2—C3—C4—C17 | 19.1 (3) | C12—C13—C14—C15 | 14.3 (3) |
C3—C4—C5—C6 | −1.2 (3) | C12—C13—C14—C1 | −151.7 (2) |
C17—C4—C5—C6 | −173.7 (2) | C2—C1—C14—C15 | −93.7 (3) |
C4—C5—C6—C7 | −13.5 (3) | C2—C1—C14—C13 | 71.8 (3) |
C4—C5—C6—C9 | 152.0 (2) | C13—C14—C15—C16 | −14.5 (3) |
C5—C6—C7—C8 | 14.9 (3) | C1—C14—C15—C16 | 151.7 (2) |
C9—C6—C7—C8 | −150.4 (2) | C14—C15—C16—C11 | 0.5 (3) |
C6—C7—C8—C3 | −1.4 (3) | C14—C15—C16—C19 | −170.0 (2) |
C4—C3—C8—C7 | −13.3 (3) | C12—C11—C16—C15 | 13.5 (3) |
C2—C3—C8—C7 | 154.6 (2) | C10—C11—C16—C15 | −153.4 (2) |
C5—C6—C9—C10 | −95.2 (2) | C12—C11—C16—C19 | −176.0 (2) |
C7—C6—C9—C10 | 69.6 (3) | C10—C11—C16—C19 | 17.1 (3) |
Experimental details
(I) | (II) | (III) | (IV) | |
Crystal data | ||||
Chemical formula | C18H16 | C20H16 | C20H16 | C20H16 |
Mr | 232.31 | 256.33 | 256.33 | 256.33 |
Crystal system, space group | Monoclinic, P21/c | Triclinic, P1 | Trigonal, P31 | Monoclinic, P21 |
Temperature (K) | 173 | 143 | 143 | 143 |
a, b, c (Å) | 7.6538 (14), 11.022 (2), 15.056 (3) | 7.6316 (10), 7.8177 (10), 12.4446 (16) | 11.8823 (12), 11.8823 (12), 8.4426 (12) | 7.6187 (10), 10.8231 (16), 8.6293 (12) |
α, β, γ (°) | 90, 99.561 (16), 90 | 78.125 (2), 72.339 (2), 73.971 (2) | 90, 90, 120 | 90, 101.230 (6), 90 |
V (Å3) | 1252.4 (4) | 673.90 (15) | 1032.3 (2) | 697.93 (17) |
Z | 4 | 2 | 3 | 2 |
Radiation type | Mo Kα | Mo Kα | Mo Kα | Mo Kα |
µ (mm−1) | 0.07 | 0.07 | 0.07 | 0.07 |
Crystal size (mm) | 0.6 × 0.3 × 0.18 | 0.42 × 0.28 × 0.26 | 0.40 × 0.20 × 0.08 | 0.40 × 0.20 × 0.18 |
Data collection | ||||
Diffractometer | Siemens P4 | Bruker SMART 1000 CCD area-detector | Bruker SMART 1000 CCD area-detector | Bruker SMART 1000 CCD area-detector |
Absorption correction | – | – | – | – |
No. of measured, independent and observed [I > 2σ(I)] reflections | 3461, 2191, 1267 | 5064, 3383, 2953 | 13844, 1719, 1536 | 7442, 1821, 1706 |
Rint | 0.024 | 0.030 | 0.081 | 0.049 |
(sin θ/λ)max (Å−1) | 0.595 | 0.671 | 0.666 | 0.667 |
Refinement | ||||
R[F2 > 2σ(F2)], wR(F2), S | 0.042, 0.103, 0.86 | 0.045, 0.126, 1.08 | 0.035, 0.088, 1.02 | 0.036, 0.098, 1.07 |
No. of reflections | 2191 | 3383 | 1719 | 1821 |
No. of parameters | 168 | 189 | 189 | 189 |
No. of restraints | 167 | 0 | 185 | 185 |
H-atom treatment | H atoms treated by a mixture of independent and constrained refinement | H atoms treated by a mixture of independent and constrained refinement | H atoms treated by a mixture of independent and constrained refinement | H atoms treated by a mixture of independent and constrained refinement |
Δρmax, Δρmin (e Å−3) | 0.19, −0.17 | 0.35, −0.23 | 0.22, −0.14 | 0.26, −0.16 |
(V) | |
Crystal data | |
Chemical formula | C20H16 |
Mr | 256.33 |
Crystal system, space group | Trigonal, P31 |
Temperature (K) | 143 |
a, b, c (Å) | 12.5475 (12), 12.5475 (12), 7.8705 (10) |
α, β, γ (°) | 90, 90, 120 |
V (Å3) | 1073.1 (2) |
Z | 3 |
Radiation type | Mo Kα |
µ (mm−1) | 0.07 |
Crystal size (mm) | 0.45 × 0.12 × 0.11 |
Data collection | |
Diffractometer | Bruker SMART 1000 CCD area-detector |
Absorption correction | – |
No. of measured, independent and observed [I > 2σ(I)] reflections | 14432, 1462, 1311 |
Rint | 0.037 |
(sin θ/λ)max (Å−1) | 0.625 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.037, 0.101, 1.05 |
No. of reflections | 1462 |
No. of parameters | 189 |
No. of restraints | 185 |
H-atom treatment | H atoms treated by a mixture of independent and constrained refinement |
Δρmax, Δρmin (e Å−3) | 0.27, −0.12 |
Computer programs: XSCANS (Siemens, 1991), SMART (Bruker, 1998), XSCANS, SAINT (Bruker, 1998), SAINT, SHELXS97 (Sheldrick, 1997), SHELXL97 (Sheldrick, 1997), XP (Siemens, 1994), SHELXL97.
Compound | C—C bridge bond lengths | C—C—C bridge bond angles | C—C—C bridgehead bond angles | Bridgehead deviations from plane | C≡C bond lengths | C—C≡C bond angles |
1 | 1.582 (3), 1.576 (3) | 111.8 (2), 113.0 (2), 112.5 (2), 113.4 (2) | 117.8 (2), 116.9 (2), 116.7 (2), 117.0 (2) | 0.162 (2), 0.148 (2), 0.150 (3), 0.154 (3) | 1.183 (3) | 179.6 (2) |
2 | 1.599 (2), 1.591 (2) | 113.0 (1), 112.4 (1), 112.9 (1), 112.7 (1) | 117.2 (1), 117.5 (1), 116.9 (1), 117.1 (1) | 0.149 (2), 0.152 (2), 0.157 (2), 0.160 (2) | 1.194 (2), 1.194 (2) | 178.1 (1), 179.3 (1) |
3 | 1.591 (3), 1.587 (3) | 111.8 (2), 112.1 (2), 112.6 (2), 112.3 (2) | 117.2 (2), 117.2 (2), 116.9 (2), 116.7 (2) | 0.158 (3), 0.148 (3), 0.147 (3), 0.156 (3) | 1.197 (3), 1.188 (3) | 179.3 (2), 177.0 (2) |
4 | 1.586 (2), 1.584 (3) | 112.2 (1), 112.6 (1), 112.2 (1), 112.0 (1) | 117.0 (1), 117.1 (1), 117.2 (1), 117.1 (1) | 0.165 (2), 0.155 (2), 0.156 (2), 0.166 (2) | 1.191 (3), 1.191 (3) | 176.6 (2), 177.5 (2) |
5 | 1.585 (4), 1.590 (3) | 112.4 (2), 112.2 (2), 112.4 (2), 112.5 (2) | 116.8 (2), 117.1 (2), 117.2 (2), 117.3 (2) | 0.150 (3), 0.153 (3), 0.150 (3), 0.154 (3) | 1.187 (4), 1.183 (4) | 177.6 (3), 178.8 (3) |
Angles are rounded where necessary to nearest 0.1°. Unless otherwise specified (see below), atom labels for columns 2–7, respectively, are: C1—C2 and C9—C10; angles at C1, C2, C9 and C10; angles at C3, C6, C11 and C14; deviations of atoms C3, C6, C11 and C14 from ring planes calculated without bridgehead atoms; bond lengths C17≡C18 and C19≡C20; angles C4—C17≡C18 and C—C19≡C20. Exceptions: for compound (I), there is only one triple bond; for compound (II), values are given for the first and second independent half molecule, whereby atom labels can be taken from Fig. 2. |
Compound | Hydrogen-bond No. | D—H···A | H···A | D—H···A | Symmetry code |
(I) | 1 | C13—H13···Cg1 | 2.67 | 165 | (1-x, -1/2+y, 1/2-z) |
2 | C5—H5···Cg2 | 2.86 | 131 | (-x, 1/2+y, 1/2-z) | |
3 | C8—H8···Cg3 | 2.82 | 130 | (1-x, -1/2+y, 1/2-z) | |
(II) | 1 | C2—H2B···Cg2 | 2.78 | 173 | (-x, -y, 1-z) |
2 | C1—H1B···Cg4 | 2.80 | 164 | (-x, 1-y, 1-z) | |
3 | C10'—H10'···Cg1 | 2.68 | 116 | (1-x, -y, 1-z) | |
4 | C2'—H2'2···Cg3 | 3.06 | 147 | (1-x, -y, 1-z) | |
(III) | 1 | C20—H20···Cg2 | 2.60 | 119 | (y-x, 1-x, -1/3+z) |
2 | C7—H7···Cg1 | 2.56 | 158 | (-y, x-y, 1/3+z) | |
3 | C18—H18···Cg3 | 2.91 | 173 | (1+y-x, 1-x, -1/3+z) | |
4 | C5—H5···Cg4 | 2.97 | 131 | (y-x, -x, -1/3+z) | |
(IV) | 1 | C8—H8···Cg2 | 2.47 | 155 | (-x, 1/2+y, 1-z) |
2 | C10—H10B···Cg1 | 2.86 | 170 | (1-x, -1/2+y, 1-z) | |
3 | C20—H20···Cg3 | 2.75 | 139 | (1-x, -1/2+y, 2-z) | |
4 | C12—H12···Cg4 | 2.91 | 127 | (-x, 1/2+y, 1-z) | |
(V) | 1 | C7—H7···Cg1 | 2.43 | 157 | (1-x+y, 1-x, -1/3+z) |
2 | C20—H20···Cg2 | 2.78 | 149 | (1-x+y, 2-x, 2/3+z) |
C—H distances are normalized to 1.08 Å (Steiner, 1998). Cg1 is the centroid of atoms C4/C5/C7/C8; Cg2 is the centroid of atoms C12/C13/C15/C16; Cg3 is the midpoint of C17≡C18; Cg4 is the midpoint of C19≡C20. Exceptions for compound (II): Cg2 is the centroid of atoms C4'/C5'/C7'/C8'; Cg3 is the midpoint of C9—C10; Cg4 is the midpoint of C9'—C10'. Exception for compound (V): Cg2 is the centroid of atoms C11/C12/C16 (see text). Hydrogen-bond numbers are shown in the packing diagrams. |
We recently described the syntheses of 4-ethynyl[2.2]paracyclophane, (I), and the four isomeric disubstituted derivatives, 4,12-diethynyl-, (II), 4,13-diethynyl-, (III), 4,15-diethynyl-, (IV), and 4,16-diethynyl[2.2]paracyclophane, (V) (Bondarenko et al., 2004). These molecules are interesting building blocks for molecular scaffolding (Hopf & Dix, 2006). We are also interested in the structures of paracyclophane derivatives and, in particular, in their packing, and have presented a description of C—H···π interactions (Desiraju & Steiner, 1999) in some pseudo-geminally substituted derivatives (El Shaieb et al., 2003). Here, we present the crystal structures of compounds (I)–(V). The disubstituted compounds (II), (III), (IV) and (V) represent the substitution patterns pseudo-para, pseudo-meta, pseudo-geminal and pseudo-ortho, respectively. To the best of our knowledge, this is the first time that all four possible isomers with a given substituent have been structurally characterized by X-ray methods.
The molecules of compounds (I)–(V) are shown in Figs. 1–5. Those of (I), (III) and (V) are chiral, although all bulk samples were racemates. Nevertheless, compounds (III), (IV) and (V) crystallize by chance in chiral space groups. Compound (II) crystallizes with two independent molecules, each of which displays imposed inversion symmetry; for this reason, the standard IUPAC numbering cannot be fully implemented for (II). For compound (V), the enantiomer in Fig. 5 is opposite to that in the scheme.
Bond lengths and angles may be considered normal. In particular, the molecules show the distortions typical of [2.2]paracyclophane systems, e.g. lengthened C—C bonds and widened angles in the bridges, narrowed ring bond angles at the bridgehead atoms, and boatlike distortion of the rings (the bridgehead atoms lie significantly out of the plane of the other four ring atoms). These dimensions are summarized in Table 1. In the pseudo-geminal isomer, (IV), the separations between the atoms of the eclipsed triple-bond systems are C4···C15 3.170 (2), C17···C19 3.371 (2) and C18···C20 3.642 (3) Å. We have utilized such close contacts in related derivatives with double bonds to form ladderanes (see, for example, Hopf et al., 2005).
The molecular packing of all five compounds can be analysed in terms of C—H···π interactions, where the acceptor system can be the triple bond or the π electron density of the rings (Desiraju & Steiner, 1999). A summary of the observed contacts is given in Table 2. The packing of compound (I) involves layers of molecules parallel to the ab plane at z ≈ 1/4, 3/4, etc. One such layer is shown in Fig. 6. The molecules adopt a herringbone-type pattern, within which the three C—H···π interactions are accommodated. We have previously pointed out (El Shaieb et al., 2003) that many simple derivatives of [2.2]paracyclophane display a common combination of two axis lengths, one of ca 7.5 Å and the other of ca 11.5 Å. These values are consistent with the formation of hydrogen-bonded layers such as that observed for (I). Because the molecules are approximately equidimensional, mutual rotations within the layer can be tolerated without disturbing the overall pattern, and thus different types of H atom (bridge or ring) can act as donors. The substituents play a less important role: in general, they are directed perpendicularly away from the layers, and thus determine the interlayer interactions and, in turn, the space group and third axis length. The only requirement is that the substituents should not be too large or themselves determine the most important secondary interactions. In compound (I), the ethynyl substituent is even capable of accepting a hydrogen bond within the layer without disturbing the 7,11 pattern.
For the ring systems, it is not always clear whether the whole ring or only a part of it is the `true' acceptor of the hydrogen bond. For compound (I), the acceptor system of hydrogen bond No. 2 might be better expressed as the triangle of atoms C11/C12/C16 forming one angled end of the `boat'. For this grouping, the hydrogen-bond parameters would be 2.69 Å and 168°, shorter and more linear than the formal contact to the ring centroid.
The packing of compound (II) is shown in Fig. 7. It too involves a layer structure, but the 7,11 pattern is not observed. Instead, hydrogen bonds 1 and 2 (the latter involving an ethynyl acceptor) combine in layers parallel to (101). The other two hydrogen bonds are formed between layers. The acceptor for hydrogen bond 3 might be better expressed as the centroid of atoms C5–C7 (2.66 Å and 134°). Hydrogen bond 4 is a borderline case.
The 31 axis of compound (III) is clearly recognisable the packing diagram shown in Fig. 8. Within the 31 helices, the short hydrogen bond No. 1, with an ethynyl H atom as donor, links successive molecules (the `true' acceptor might be the centroid of atoms C11/C12/C16, with hydrogen-bond parameters of 2.56 Å, 138°). The other three hydrogen bonds, one short and two long, link adjacent helices. It is noteworthy that hydrogen bond 3 is from an ethynyl group to a symmetry equivalent of the same group.
With compound (IV), we return to the 7,11 pattern (Fig. 9), with one very short hydrogen bond (No. 1). The ethynyl groups play no role within the layer, but instead are involved in interlayer contacts.
Compound (V) crystallizes, like (III), in the space group P31. The packing diagram (Fig. 10) shows that the helices are assembled via a different type of hydrogen bond from those in (III), with a ring H atom as donor to the symmetry equivalent of the same ring. The first impression is that this is the only significant interaction (no other centroids or triple bonds appear to be involved in short contacts), but closer inspection reveals that the atom grouping C11/C12/C16 is the acceptor for hydrogen bond 2, which links adjacent helices.