Supporting information
Crystallographic Information File (CIF) https://doi.org/10.1107/S1600536807020697/hk2237sup1.cif | |
Structure factor file (CIF format) https://doi.org/10.1107/S1600536807020697/hk2237Isup2.hkl |
CCDC reference: 651382
Key indicators
- Single-crystal X-ray study
- T = 298 K
- Mean (C-C) = 0.003 Å
- R factor = 0.050
- wR factor = 0.140
- Data-to-parameter ratio = 15.5
checkCIF/PLATON results
No syntax errors found
Alert level C PLAT066_ALERT_1_C Predicted and Reported Transmissions Identical . ?
0 ALERT level A = In general: serious problem 0 ALERT level B = Potentially serious problem 1 ALERT level C = Check and explain 0 ALERT level G = General alerts; check 1 ALERT type 1 CIF construction/syntax error, inconsistent or missing data 0 ALERT type 2 Indicator that the structure model may be wrong or deficient 0 ALERT type 3 Indicator that the structure quality may be low 0 ALERT type 4 Improvement, methodology, query or suggestion 0 ALERT type 5 Informative message, check
A mixture of benzocyclobutene-4-boronic acid (29.6 mg, 0.20 mmol), 4-bromobenzocyclobutene (85.0 mg, 0.46 mmol), tetrabutylammonium bromide (6.44 mg, 0.02 mmol) and palladium chloride (2.83 mg, 0.016 mmol) in ethanol (10 ml) was stirred for 1 h under nitrogen atmosphere at room temperature. Potassium carbonate (580 mg, 0.42 mmol) was then added and the mixture was stirred vigorously for 22 h. The reaction mixture was poured into distilled water (15 ml) and then extracted with chloroform (20 ml) three times. The combined organic phase was washed with distilled water (30 ml) and dried over sodium sulfate. Removal of the solvent under reduced pressure gave a grey-white solid, which could be purified by chromatography on silica gel using petroleum ether, as eluent to recover excess 4-bromobenzocyclobutene first, then using a mixture of petroleum ether and toluene (25:1) to afford (I) (yield; 37.0 mg, 90%, m.p. 333 K). Crystals of (I) suitable for X-ray diffraction was obtained by slow evaporation of hexane.
H atoms were positioned geometrically, with C—H = 0.93 and 0.97 Å for aromatic and methylene H, respectively, and constrained to ride on their parent atoms, with Uiso(H) = 1.2Ueq(C).
Benzocyclobutenes (BCBs) are a family of thermally polymerisable monomers for high-performance polymers, which have been widely used in the microelectronics industry because of their low dielectric constant, low dispersion factor, low water up-take, high thermal and chemical stabilities, and ease of processing (Kirchhoff & Bruza, 1993). Homopolymers and copolymers of aryl bridged bisbenzocyclobutene monomers (bisBCB) also exhibit excellent properties (Corley & Wong, 1992).
In the molecule of the title compound, (I), (Fig. 1), the bond lengths and angles are within normal ranges (Allen et al., 1987). Rings A (C1—C3/C8), B (C3—C8), C (C9—C14) and D (C11/C12/C15/C16) are, of course, planar and the dihedral angles between them are A/B = 1.92 (3)°, C/D = 0.27 (3)° and B/C = 38.00 (4)°.
As can be seen from the packing diagram, (Fig. 2), the molecules are elongated along the c axis and stacked along the b axis.
For general backgroud, see: Allen et al. (1987); Kirchhoff & Bruza (1993); Corley & Wong (1992).
Data collection: CAD-4 Software (Enraf–Nonius, 1989); cell refinement: CAD-4 Software; data reduction: XCAD4 (Harms & Wocadlo, 1995); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SHELXTL (Bruker, 2000); software used to prepare material for publication: SHELXTL.
Fig. 1. The molecular structure of the title molecule, with the atom-numbering scheme. Displacement ellipsoids are drawn at the 30% probability level. | |
Fig. 2. A packing diagram for (I). |
C16H14 | F(000) = 440 |
Mr = 206.27 | Dx = 1.192 Mg m−3 |
Monoclinic, P21/n | Melting point: 333 K |
Hall symbol: -P 2yn | Mo Kα radiation, λ = 0.71073 Å |
a = 8.0250 (16) Å | Cell parameters from 25 reflections |
b = 11.365 (2) Å | θ = 10–13° |
c = 12.850 (3) Å | µ = 0.07 mm−1 |
β = 101.19 (3)° | T = 298 K |
V = 1149.7 (4) Å3 | Block, colorless |
Z = 4 | 0.30 × 0.20 × 0.20 mm |
Enraf–Nonius CAD-4 diffractometer | 1414 reflections with I > 2σ(I) |
Radiation source: fine-focus sealed tube | Rint = 0.000 |
Graphite monochromator | θmax = 26.0°, θmin = 2.4° |
ω/2θ scans | h = −9→9 |
Absorption correction: ψ scan (North et al., 1968) | k = 0→14 |
Tmin = 0.980, Tmax = 0.987 | l = 0→15 |
2248 measured reflections | 3 standard reflections every 200 reflections |
2248 independent reflections | intensity decay: none |
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)] = 0.050 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.140 | H-atom parameters constrained |
S = 1.08 | w = 1/[σ2(Fo2) + (0.0408P)2 + 0.3817P] where P = (Fo2 + 2Fc2)/3 |
2248 reflections | (Δ/σ)max < 0.001 |
145 parameters | Δρmax = 0.14 e Å−3 |
0 restraints | Δρmin = −0.13 e Å−3 |
C16H14 | V = 1149.7 (4) Å3 |
Mr = 206.27 | Z = 4 |
Monoclinic, P21/n | Mo Kα radiation |
a = 8.0250 (16) Å | µ = 0.07 mm−1 |
b = 11.365 (2) Å | T = 298 K |
c = 12.850 (3) Å | 0.30 × 0.20 × 0.20 mm |
β = 101.19 (3)° |
Enraf–Nonius CAD-4 diffractometer | 1414 reflections with I > 2σ(I) |
Absorption correction: ψ scan (North et al., 1968) | Rint = 0.000 |
Tmin = 0.980, Tmax = 0.987 | 3 standard reflections every 200 reflections |
2248 measured reflections | intensity decay: none |
2248 independent reflections |
R[F2 > 2σ(F2)] = 0.050 | 0 restraints |
wR(F2) = 0.140 | H-atom parameters constrained |
S = 1.08 | Δρmax = 0.14 e Å−3 |
2248 reflections | Δρmin = −0.13 e Å−3 |
145 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 | 0.0790 (4) | 0.9190 (3) | 0.31338 (18) | 0.0752 (8) | |
H1A | 0.1490 | 0.9893 | 0.3212 | 0.090* | |
H1B | −0.0403 | 0.9381 | 0.2901 | 0.090* | |
C2 | 0.1442 (3) | 0.8183 (3) | 0.24864 (19) | 0.0748 (8) | |
H2A | 0.0580 | 0.7859 | 0.1925 | 0.090* | |
H2B | 0.2470 | 0.8375 | 0.2231 | 0.090* | |
C3 | 0.1737 (3) | 0.7478 (2) | 0.34986 (18) | 0.0589 (6) | |
C4 | 0.2271 (3) | 0.6419 (2) | 0.3941 (2) | 0.0673 (7) | |
H4A | 0.2675 | 0.5831 | 0.3553 | 0.081* | |
C5 | 0.2181 (3) | 0.6263 (2) | 0.50072 (19) | 0.0600 (6) | |
H5A | 0.2547 | 0.5555 | 0.5336 | 0.072* | |
C6 | 0.1557 (3) | 0.7139 (2) | 0.55964 (17) | 0.0494 (6) | |
C7 | 0.1062 (3) | 0.8223 (2) | 0.51261 (17) | 0.0552 (6) | |
H7A | 0.0685 | 0.8829 | 0.5508 | 0.066* | |
C8 | 0.1155 (3) | 0.8361 (2) | 0.40726 (17) | 0.0558 (6) | |
C9 | 0.1413 (3) | 0.6890 (2) | 0.67190 (17) | 0.0502 (6) | |
C10 | 0.1747 (3) | 0.7754 (2) | 0.74977 (17) | 0.0531 (6) | |
H10A | 0.2084 | 0.8507 | 0.7344 | 0.064* | |
C11 | 0.1560 (3) | 0.7448 (2) | 0.85081 (17) | 0.0518 (6) | |
C12 | 0.1065 (3) | 0.6355 (2) | 0.87572 (18) | 0.0559 (6) | |
C13 | 0.0705 (3) | 0.5482 (2) | 0.8009 (2) | 0.0624 (7) | |
H13A | 0.0351 | 0.4738 | 0.8177 | 0.075* | |
C14 | 0.0897 (3) | 0.5770 (2) | 0.69819 (18) | 0.0561 (6) | |
H14A | 0.0675 | 0.5198 | 0.6455 | 0.067* | |
C15 | 0.1723 (3) | 0.7919 (2) | 0.96359 (17) | 0.0634 (7) | |
H15A | 0.0934 | 0.8546 | 0.9710 | 0.076* | |
H15B | 0.2874 | 0.8116 | 0.9981 | 0.076* | |
C16 | 0.1122 (4) | 0.6654 (2) | 0.99105 (19) | 0.0743 (8) | |
H16A | 0.1963 | 0.6215 | 1.0405 | 0.089* | |
H16B | 0.0023 | 0.6640 | 1.0119 | 0.089* |
U11 | U22 | U33 | U12 | U13 | U23 | |
C1 | 0.091 (2) | 0.085 (2) | 0.0501 (14) | −0.0114 (16) | 0.0156 (14) | 0.0022 (14) |
C2 | 0.0746 (18) | 0.104 (2) | 0.0470 (14) | −0.0247 (16) | 0.0143 (13) | −0.0124 (14) |
C3 | 0.0588 (15) | 0.0726 (17) | 0.0474 (13) | −0.0176 (13) | 0.0153 (11) | −0.0137 (12) |
C4 | 0.0708 (17) | 0.0742 (18) | 0.0616 (16) | −0.0081 (14) | 0.0244 (13) | −0.0249 (14) |
C5 | 0.0663 (16) | 0.0543 (15) | 0.0627 (15) | −0.0014 (12) | 0.0207 (12) | −0.0090 (12) |
C6 | 0.0493 (13) | 0.0538 (14) | 0.0466 (12) | −0.0040 (11) | 0.0133 (10) | −0.0033 (11) |
C7 | 0.0649 (15) | 0.0566 (14) | 0.0475 (13) | −0.0039 (12) | 0.0190 (11) | −0.0045 (11) |
C8 | 0.0562 (14) | 0.0659 (16) | 0.0456 (13) | −0.0089 (12) | 0.0103 (11) | −0.0033 (12) |
C9 | 0.0493 (13) | 0.0526 (14) | 0.0509 (13) | −0.0027 (11) | 0.0150 (10) | −0.0007 (11) |
C10 | 0.0583 (14) | 0.0491 (13) | 0.0538 (14) | −0.0041 (11) | 0.0154 (11) | −0.0001 (11) |
C11 | 0.0493 (13) | 0.0601 (15) | 0.0465 (13) | 0.0039 (11) | 0.0106 (10) | 0.0008 (11) |
C12 | 0.0541 (14) | 0.0611 (15) | 0.0537 (14) | 0.0060 (12) | 0.0133 (11) | 0.0095 (12) |
C13 | 0.0701 (17) | 0.0514 (15) | 0.0701 (16) | −0.0004 (12) | 0.0243 (13) | 0.0117 (13) |
C14 | 0.0597 (15) | 0.0515 (14) | 0.0588 (14) | −0.0037 (12) | 0.0159 (12) | −0.0037 (12) |
C15 | 0.0622 (16) | 0.0784 (18) | 0.0483 (13) | 0.0037 (14) | 0.0073 (11) | −0.0027 (13) |
C16 | 0.0791 (19) | 0.093 (2) | 0.0537 (15) | 0.0096 (16) | 0.0203 (13) | 0.0148 (14) |
C1—C8 | 1.514 (3) | C9—C10 | 1.390 (3) |
C1—C2 | 1.564 (4) | C9—C14 | 1.401 (3) |
C1—H1A | 0.9700 | C10—C11 | 1.380 (3) |
C1—H1B | 0.9700 | C10—H10A | 0.9300 |
C2—C3 | 1.507 (3) | C11—C12 | 1.361 (3) |
C2—H2A | 0.9700 | C11—C15 | 1.526 (3) |
C2—H2B | 0.9700 | C12—C13 | 1.373 (3) |
C3—C4 | 1.364 (4) | C12—C16 | 1.512 (3) |
C3—C8 | 1.380 (3) | C13—C14 | 1.397 (3) |
C4—C5 | 1.397 (3) | C13—H13A | 0.9300 |
C4—H4A | 0.9300 | C14—H14A | 0.9300 |
C5—C6 | 1.401 (3) | C15—C16 | 1.578 (4) |
C5—H5A | 0.9300 | C15—H15A | 0.9700 |
C6—C7 | 1.395 (3) | C15—H15B | 0.9700 |
C6—C9 | 1.497 (3) | C16—H16A | 0.9700 |
C7—C8 | 1.379 (3) | C16—H16B | 0.9700 |
C7—H7A | 0.9300 | ||
C8—C1—C2 | 86.3 (2) | C10—C9—C14 | 119.6 (2) |
C8—C1—H1A | 114.3 | C10—C9—C6 | 121.3 (2) |
C2—C1—H1A | 114.3 | C14—C9—C6 | 119.1 (2) |
C8—C1—H1B | 114.3 | C11—C10—C9 | 117.2 (2) |
C2—C1—H1B | 114.3 | C11—C10—H10A | 121.4 |
H1A—C1—H1B | 111.4 | C9—C10—H10A | 121.4 |
C3—C2—C1 | 86.72 (18) | C12—C11—C10 | 122.8 (2) |
C3—C2—H2A | 114.2 | C12—C11—C15 | 94.11 (19) |
C1—C2—H2A | 114.2 | C10—C11—C15 | 143.1 (2) |
C3—C2—H2B | 114.2 | C11—C12—C13 | 121.8 (2) |
C1—C2—H2B | 114.2 | C11—C12—C16 | 94.1 (2) |
H2A—C2—H2B | 111.4 | C13—C12—C16 | 144.1 (2) |
C4—C3—C8 | 122.0 (2) | C12—C13—C14 | 116.5 (2) |
C4—C3—C2 | 144.4 (2) | C12—C13—H13A | 121.8 |
C8—C3—C2 | 93.5 (2) | C14—C13—H13A | 121.8 |
C3—C4—C5 | 116.7 (2) | C13—C14—C9 | 122.2 (2) |
C3—C4—H4A | 121.6 | C13—C14—H14A | 118.9 |
C5—C4—H4A | 121.6 | C9—C14—H14A | 118.9 |
C4—C5—C6 | 122.1 (2) | C11—C15—C16 | 85.38 (19) |
C4—C5—H5A | 119.0 | C11—C15—H15A | 114.4 |
C6—C5—H5A | 119.0 | C16—C15—H15A | 114.4 |
C7—C6—C5 | 119.7 (2) | C11—C15—H15B | 114.4 |
C7—C6—C9 | 121.0 (2) | C16—C15—H15B | 114.4 |
C5—C6—C9 | 119.3 (2) | H15A—C15—H15B | 111.5 |
C8—C7—C6 | 117.4 (2) | C12—C16—C15 | 86.41 (18) |
C8—C7—H7A | 121.3 | C12—C16—H16A | 114.3 |
C6—C7—H7A | 121.3 | C15—C16—H16A | 114.3 |
C7—C8—C3 | 122.0 (2) | C12—C16—H16B | 114.3 |
C7—C8—C1 | 144.5 (2) | C15—C16—H16B | 114.3 |
C3—C8—C1 | 93.4 (2) | H16A—C16—H16B | 111.4 |
C8—C1—C2—C3 | −0.28 (19) | C7—C6—C9—C14 | 141.2 (2) |
C1—C2—C3—C4 | 178.6 (4) | C5—C6—C9—C14 | −38.0 (3) |
C1—C2—C3—C8 | 0.3 (2) | C14—C9—C10—C11 | 0.5 (3) |
C8—C3—C4—C5 | 0.8 (4) | C6—C9—C10—C11 | 179.2 (2) |
C2—C3—C4—C5 | −177.2 (3) | C9—C10—C11—C12 | −0.2 (3) |
C3—C4—C5—C6 | 0.7 (4) | C9—C10—C11—C15 | 179.1 (3) |
C4—C5—C6—C7 | −2.4 (4) | C10—C11—C12—C13 | −0.6 (4) |
C4—C5—C6—C9 | 176.9 (2) | C15—C11—C12—C13 | 179.9 (2) |
C5—C6—C7—C8 | 2.5 (3) | C10—C11—C12—C16 | −179.6 (2) |
C9—C6—C7—C8 | −176.8 (2) | C15—C11—C12—C16 | 0.8 (2) |
C6—C7—C8—C3 | −1.0 (4) | C11—C12—C13—C14 | 0.9 (4) |
C6—C7—C8—C1 | 176.4 (3) | C16—C12—C13—C14 | 179.3 (3) |
C4—C3—C8—C7 | −0.6 (4) | C12—C13—C14—C9 | −0.6 (4) |
C2—C3—C8—C7 | 178.2 (2) | C10—C9—C14—C13 | −0.1 (4) |
C4—C3—C8—C1 | −179.1 (2) | C6—C9—C14—C13 | −178.8 (2) |
C2—C3—C8—C1 | −0.3 (2) | C12—C11—C15—C16 | −0.8 (2) |
C2—C1—C8—C7 | −177.5 (3) | C10—C11—C15—C16 | 179.8 (3) |
C2—C1—C8—C3 | 0.3 (2) | C11—C12—C16—C15 | −0.8 (2) |
C7—C6—C9—C10 | −37.5 (3) | C13—C12—C16—C15 | −179.4 (4) |
C5—C6—C9—C10 | 143.3 (2) | C11—C15—C16—C12 | 0.73 (18) |
Experimental details
Crystal data | |
Chemical formula | C16H14 |
Mr | 206.27 |
Crystal system, space group | Monoclinic, P21/n |
Temperature (K) | 298 |
a, b, c (Å) | 8.0250 (16), 11.365 (2), 12.850 (3) |
β (°) | 101.19 (3) |
V (Å3) | 1149.7 (4) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 0.07 |
Crystal size (mm) | 0.30 × 0.20 × 0.20 |
Data collection | |
Diffractometer | Enraf–Nonius CAD-4 |
Absorption correction | ψ scan (North et al., 1968) |
Tmin, Tmax | 0.980, 0.987 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 2248, 2248, 1414 |
Rint | 0.000 |
(sin θ/λ)max (Å−1) | 0.616 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.050, 0.140, 1.08 |
No. of reflections | 2248 |
No. of parameters | 145 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.14, −0.13 |
Computer programs: CAD-4 Software (Enraf–Nonius, 1989), CAD-4 Software, XCAD4 (Harms & Wocadlo, 1995), SHELXS97 (Sheldrick, 1997), SHELXL97 (Sheldrick, 1997), SHELXTL (Bruker, 2000), SHELXTL.
Benzocyclobutenes (BCBs) are a family of thermally polymerisable monomers for high-performance polymers, which have been widely used in the microelectronics industry because of their low dielectric constant, low dispersion factor, low water up-take, high thermal and chemical stabilities, and ease of processing (Kirchhoff & Bruza, 1993). Homopolymers and copolymers of aryl bridged bisbenzocyclobutene monomers (bisBCB) also exhibit excellent properties (Corley & Wong, 1992).
In the molecule of the title compound, (I), (Fig. 1), the bond lengths and angles are within normal ranges (Allen et al., 1987). Rings A (C1—C3/C8), B (C3—C8), C (C9—C14) and D (C11/C12/C15/C16) are, of course, planar and the dihedral angles between them are A/B = 1.92 (3)°, C/D = 0.27 (3)° and B/C = 38.00 (4)°.
As can be seen from the packing diagram, (Fig. 2), the molecules are elongated along the c axis and stacked along the b axis.