The title compound, C
42H
42O
7Si
2, was obtained as a by-product from the reaction of (
p-Tol-O)
3SiCl with [PhC(S)S]
2Mg·2THF (
p-Tol is
p-tolyl and THF is tetrahydrofuran). The molecule has
symmetry and is an example of a compound with an Si-O-Si valence angle of 180°. The distribution of this angle within disiloxanes is briefly described and discussed.
Supporting information
CCDC reference: 627646
Key indicators
- Single-crystal X-ray study
- T = 120 K
- Mean (C-C) = 0.002 Å
- R factor = 0.047
- wR factor = 0.124
- Data-to-parameter ratio = 22.9
checkCIF/PLATON results
No syntax errors found
Alert level B
PLAT396_ALERT_2_B Deviating Si-O-Si Angle from 150 Deg for O1 180.00 Deg.
0 ALERT level A = In general: serious problem
1 ALERT level B = Potentially serious problem
0 ALERT level C = Check and explain
0 ALERT level G = General alerts; check
0 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
1 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
Data collection: CrysAlis CCD (Oxford Diffraction, 2005); cell refinement: CrysAlis RED (Oxford Diffraction, 2005); data reduction: CrysAlis RED; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997); software used to prepare material for publication: WinGX (Farrugia, 1999).
Hexakis(4-methylphenoxy)disiloxane
top
Crystal data top
C42H42O7Si2 | Dx = 1.272 Mg m−3 |
Mr = 714.94 | Mo Kα radiation, λ = 0.71073 Å |
Hexagonal, R3 | Cell parameters from 1223 reflections |
Hall symbol: -R 3 | θ = 2.6–32.6° |
a = 14.1520 (18) Å | µ = 0.15 mm−1 |
c = 16.149 (2) Å | T = 120 K |
V = 2801.0 (6) Å3 | Prism, colourless |
Z = 3 | 0.5 × 0.3 × 0.18 mm |
F(000) = 1134 | |
Data collection top
Oxford Diffraction KM-4-CCD diffractometer | Rint = 0.038 |
ω scans | θmax = 29.9°, θmin = 2.9° |
6943 measured reflections | h = −18→19 |
1810 independent reflections | k = −15→19 |
1705 reflections with I > 2σ(I) | l = −22→22 |
Refinement top
Refinement on F2 | 0 restraints |
Least-squares matrix: full | H-atom parameters constrained |
R[F2 > 2σ(F2)] = 0.047 | w = 1/[σ2(Fo2) + (0.0687P)2 + 2.6331P] where P = (Fo2 + 2Fc2)/3 |
wR(F2) = 0.124 | (Δ/σ)max = 0.001 |
S = 1.07 | Δρmax = 0.44 e Å−3 |
1810 reflections | Δρmin = −0.24 e Å−3 |
79 parameters | |
Special details top
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. |
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top | x | y | z | Uiso*/Ueq | |
C1 | 0.10502 (9) | −0.11280 (9) | 0.60890 (7) | 0.0233 (2) | |
C2 | 0.04689 (10) | −0.21491 (10) | 0.64574 (8) | 0.0292 (3) | |
H2 | −0.0054 | −0.2281 | 0.6876 | 0.035* | |
C3 | 0.06634 (11) | −0.29740 (11) | 0.62044 (8) | 0.0314 (3) | |
H3 | 0.0269 | −0.3672 | 0.6458 | 0.038* | |
C4 | 0.14204 (10) | −0.28065 (10) | 0.55894 (8) | 0.0275 (3) | |
C5 | 0.19861 (9) | −0.17764 (10) | 0.52273 (8) | 0.0253 (2) | |
H5 | 0.2502 | −0.1646 | 0.4803 | 0.03* | |
C6 | 0.18088 (9) | −0.09329 (9) | 0.54761 (7) | 0.0235 (2) | |
H6 | 0.2205 | −0.0233 | 0.5227 | 0.028* | |
C7 | 0.16192 (13) | −0.37181 (12) | 0.53334 (10) | 0.0388 (3) | |
H7A | 0.212 | −0.3482 | 0.486 | 0.047* | |
H7B | 0.0925 | −0.4359 | 0.5177 | 0.047* | |
H7C | 0.1942 | −0.3906 | 0.5797 | 0.047* | |
O1 | 0 | 0 | 0.5 | 0.0234 (4) | |
O2 | 0.09017 (7) | −0.02751 (8) | 0.63562 (5) | 0.0277 (2) | |
Si1 | 0 | 0 | 0.59925 (3) | 0.02169 (16) | |
Atomic displacement parameters (Å2) top | U11 | U22 | U33 | U12 | U13 | U23 |
C1 | 0.0225 (5) | 0.0248 (5) | 0.0219 (5) | 0.0113 (4) | −0.0053 (4) | 0.0011 (4) |
C2 | 0.0283 (6) | 0.0314 (6) | 0.0242 (5) | 0.0120 (5) | 0.0029 (4) | 0.0070 (4) |
C3 | 0.0323 (6) | 0.0259 (6) | 0.0307 (6) | 0.0107 (5) | 0.0001 (5) | 0.0103 (4) |
C4 | 0.0256 (5) | 0.0245 (5) | 0.0330 (6) | 0.0131 (4) | −0.0056 (4) | 0.0037 (4) |
C5 | 0.0193 (5) | 0.0261 (5) | 0.0301 (5) | 0.0110 (4) | −0.0010 (4) | 0.0043 (4) |
C6 | 0.0208 (5) | 0.0214 (5) | 0.0260 (5) | 0.0088 (4) | −0.0029 (4) | 0.0046 (4) |
C7 | 0.0379 (7) | 0.0290 (6) | 0.0544 (9) | 0.0203 (6) | −0.0037 (6) | 0.0030 (6) |
O1 | 0.0253 (6) | 0.0253 (6) | 0.0197 (8) | 0.0127 (3) | 0 | 0 |
O2 | 0.0301 (4) | 0.0316 (4) | 0.0247 (4) | 0.0179 (4) | −0.0068 (3) | −0.0042 (3) |
Si1 | 0.0236 (2) | 0.0236 (2) | 0.0178 (2) | 0.01180 (10) | 0 | 0 |
Geometric parameters (Å, º) top
C1—C6 | 1.3827 (16) | C5—H5 | 0.95 |
C1—C2 | 1.3893 (16) | C6—H6 | 0.95 |
C1—O2 | 1.3932 (14) | C7—H7A | 0.98 |
C2—C3 | 1.3882 (19) | C7—H7B | 0.98 |
C2—H2 | 0.95 | C7—H7C | 0.98 |
C3—C4 | 1.3916 (19) | O1—Si1i | 1.6027 (6) |
C3—H3 | 0.95 | O1—Si1 | 1.6027 (5) |
C4—C5 | 1.3931 (16) | O2—Si1 | 1.6192 (9) |
C4—C7 | 1.5092 (18) | Si1—O2ii | 1.6192 (9) |
C5—C6 | 1.3960 (16) | Si1—O2iii | 1.6192 (9) |
| | | |
C6—C1—C2 | 120.73 (11) | C1—C6—H6 | 120.4 |
C6—C1—O2 | 119.15 (10) | C5—C6—H6 | 120.4 |
C2—C1—O2 | 120.07 (11) | C4—C7—H7A | 109.5 |
C3—C2—C1 | 119.04 (12) | C4—C7—H7B | 109.5 |
C3—C2—H2 | 120.5 | H7A—C7—H7B | 109.5 |
C1—C2—H2 | 120.5 | C4—C7—H7C | 109.5 |
C2—C3—C4 | 121.75 (11) | H7A—C7—H7C | 109.5 |
C2—C3—H3 | 119.1 | H7B—C7—H7C | 109.5 |
C4—C3—H3 | 119.1 | Si1i—O1—Si1 | 180 |
C3—C4—C5 | 117.94 (11) | C1—O2—Si1 | 125.05 (7) |
C3—C4—C7 | 120.43 (11) | O1—Si1—O2ii | 111.27 (4) |
C5—C4—C7 | 121.62 (12) | O1—Si1—O2iii | 111.27 (4) |
C4—C5—C6 | 121.27 (11) | O2ii—Si1—O2iii | 107.61 (4) |
C4—C5—H5 | 119.4 | O1—Si1—O2 | 111.27 (4) |
C6—C5—H5 | 119.4 | O2ii—Si1—O2 | 107.61 (4) |
C1—C6—C5 | 119.27 (10) | O2iii—Si1—O2 | 107.61 (4) |
Symmetry codes: (i) −x, −y, −z+1; (ii) −y, x−y, z; (iii) −x+y, −x, z. |