R. Tacke et al. · Improved Synthesis of HOPh2Si-SiPh2OH
735
59.6 MHz). CDCl3 was used as solvent. Chemical shifts 7.40 and 7.45 - 7.54 (m, 20 H, SiPh). – 13
C
1H NMR:
(ppm) were determined relative to internal CHCl3 (1H, =
= 127.8 (C-2/C-6 or C-3/C-5, SiPh), 129.7 (C-4, SiPh),
7.24), internal CDCl3 (13C, = 77.0), or external TMS 134.2 (C-1, SiPh), 136.2 (C-2/C-6 or C-3/C-5, SiPh). –
(29Si, = 0).
29Si 1H NMR: = –10.4. – C24H22O2Si2 (398.6): calcd.
C 72.32, H 5.56; found C 72.2, H 5.6.
1,2-Bis(diethylamino)-1,1,2,2-tetraphenyldisilane (1)
This compound was synthesized according to ref. [3].
1,5-Dihydroxy-1,1,2,2,4,4,5,5-octaphenyl-3-oxa-
1,2,4,5-tetrasilapentane-Hemibenzene (4 1/2C6H6)
1,2-Dichloro-1,1,2,2-tetraphenyldisilane (2)
Compound 4 1/2C6H6 wasformed in minor amounts as
aby-productin thecrystallization of 3. A procedurefor the
synthesis of 4 1/2C6H6 has been reported elsewhere [2].
Acetyl chloride (1.60 g, 20.4 mmol) was added
to a stirred solution of 1 (5.00 g, 9.83 mmol) in
dichloromethane (40 ml) at 0 C and the mixture then
stirred for 1 d at r. t. The solvent was removed under
reduced pressure and the resulting solid recrystallized
Crystal structure analyses of 3 and 4 1/2C6H6
Suitable single crystals of 3 and 4 1/2C6H6 were ob-
from toluene / petroleum ether (40 - 60 C) [1:1 (v/v)] to tained by crystallization of 3 from benzene/petroleum
give 3.81 g (8.75 mmol) of a colorless crystalline prod- ether (60 - 70 C) (see preparation). The crystals were
1
uct (yield 89%). – M. p. 106 - 109 C. – H NMR:
=
mounted in inert oil (perfluoroalkyl ether, ABCR) on a
7.26 - 7.69 (m, 20 H, SiPh). – 13C 1H NMR: = 128.2 glass fiber and then transferred to the cold nitrogen gas
(C-2/C-6 or C-3/C-5, SiPh), 130.8 (C-4, SiPh), 132.2 (C- stream of the diffractometer (Stoe IPDS; graphite-mono-
1, SiPh), 135.0 (C-2/C-6 or C-3/C-5, SiPh). – 29Si 1H
chromated Mo-K radiation, = 0.71073 A). The struc-
˚
NMR: = –4.6. – C24H20Cl2Si2 (435.5): calcd. C 66.19, tures were solved by direct methods (SHELXS-97) [9]
H 4.63; found C 66.2, H 4.7.
and refined by full-matrix least-squares on F2 with all
unique reflections (SHELXL-97) [10]. For the CH hy-
drogen atoms of 3 and 4 1/2C6H6, a riding model was
employed. The OH hydrogen atoms of 3 were localized in
the Fourier synthesis and refined freely. The OH hydrogen
atoms of 4 1/2C6H6 were placed on ideal positions and re-
fined using distance restraints. Crystallographic data (ex-
cluding structure factors) have been deposited with the
Cambridge Crystallographic Data Centre as supplemen-
tary publication no CCDC-181214 (3) and CCDC-181215
(4 1/2C6H6). Copies of the data can be obtained free of
charge on application to CCDC, 12 Union Road, Cam-
bridge CB2 1EZ, UK [Fax: (+44)1223-336-033; e-mail:
deposit@ccdc.cam.ac.uk].
1,1,2,2-Tetraphenyldisilane-1,2-diol (3)
A solution of 2 (2.00g, 4.59 mmol) in dichloromethane
(7 ml) was added dropwise at 0 C to a stirred mixture
of water (17 ml), diethyl ether (5 ml), and ammonium
carbonate (618 mg, 6.43 mmol). Stirring was continued
for 1 h at the same temperature and the aqueous phase
then saturated with sodium chloride. The two phases were
separated, and the aqueous layer was extracted with di-
ethyl ether (2
20 ml). The combined organic phases
were dried over anhydroussodium sulfate, and the solvent
was removed under reduced pressure. The resulting crude
product was recrystallized from benzene / petroleum ether
(60 - 70 C) [1:1 (v/v); cooling of a boiling saturated so-
lution to room temperature] to give 1.70 g (4.26 mmol) of
a colorless crystalline product (yield 93%). – M. p. 138 -
140 C. – 1H NMR: = 2.65 (br. s, 2 H, SiOH), 7.21 -
Acknowledgments
This work was supported by the Deutsche Forschungs-
gemeinschaft and the Fonds der Chemischen Industrie.
[1] R. Tacke, C. Burschka, J. Heermann, I. Richter, B. Wagner,
R. Willeke, Eur. J. Inorg. Chem. 2211 (2001)
[2] H. J. S. Winkler, H. Gilman, J. Org. Chem. 26, 1265 (1961).
[3] Synthesis of 1: K. Tamao, A. Kawachi, Y. Nakagawa, Y. Ito,
J. Organomet. Chem. 473, 29 (1994).
[4] Crystal structure analysis of 1: F. Huppmann, M. Nolte-
meyer, A. Meller, J. Organomet. Chem. 483, 217
(1994).
[5] Crystal structure analysis of HO(t-Bu)2Si-Si(t-Bu)2OH:
R. West, E. K. Pham, J. Organomet. Chem. 403, 43 (1991).
[6] Crystal structure analysis of HOMe2Si-SiMe2OH: M. Pras-
se, H. Reinke, C. Wendler, H. Kelling, J. Organomet. Chem.
577, 342 (1999).
[7] Crystal structure analysis of the all-trans-isomer of 2,3,5,
6-tetramethyl-2,3,5,6-tetraphenyl-1,4-dioxa-2,3,5,6-tetra-
silacyclohexane: V. V. Semenov, E. Y. Ladilina, Y. A.
Kurskii, S. Y. Khorshev, N. P. Makarenko, G. A. Dom-
rachev, L. N. Zakharov, G. K. Fukin, Y. T. Struchkov,
Russ. Chem. Bull. 45, 2420 (1996).
[8] The hydrogen-bonding system was analyzed by using the
program PLATON: A. L. Spek, PLATON, University of
Utrecht, The Netherlands (1998).
[9] G. M. Sheldrick, SHELXS-97, University of Go¨ttingen,
Germany (1997); G. M. Sheldrick, Acta Crystallogr. A
46, 467 (1990).
[10] G. M. Sheldrick, SHELXL-97, University of Go¨ttingen,
Germany (1997).
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