Dendritic Nanosized Building Block for Siloxane-Based Materials
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conducted with an electron-impact ionizer. XRD patterns were recorded
on a Mac Science MXP3 diffractometer with Ni-filtered CuKa radiation.
An optical microscopic image of DMS-1 crystals was obtained with a dig-
ital microscope (Thanko Inc.). FTIR spectra were obtained on a JASCO
FT/IR 6100 spectrometer and a Perkin–Elmer Spectrum One spectrome-
ter by using KBr pellets with a nominal resolution of 2.0 cmÀ1. Nitrogen
adsorption measurements were performed by an Autosorb-1 instrument
(Quantachrome Instruments, Inc.) at À1968C. Samples were preheated at
1208C for 3 h under a pressure of about 1.3 Pa.
Project “Functional Designs of Silicon–Oxygen-Based Compounds by
Precise Synthetic Strategies”, and the Global COE program “Practical
Chemical Wisdom” from MEXT, Japan. K.K. is grateful for financial sup-
port provided through a Grant-in-Aid for JSPS Fellow from MEXT.
[1] Silicon-Containing Polymers: The Science and Technology of Their
Synthesis and Applications (Eds.: R. G. Jones, W. Ando, J. Chojnow-
ski), Kluwer Academic, Dordrecht, The Netherlands, 2000.
quioxanes (Advances in Silicon Science), Vol. 3 (Ed.: C. Hartmann-
Thompson), Springer, Berlin, Heidelberg, 2011.
Containing Dendritic Polymers (Advances in Silicon Science), Vol. 2
(Eds.: D. P. Radivoj, O. J. Michael), Springer, Berlin, Heidelberg,
2009.
[6] For example: a) W. Stçber, A. Fink, E. Bohn, J. Colloid Interface
Sci. 1968, 26, 62–69; b) T. Yokoi, Y. Sakamoto, O. Terasaki, Y.
Materials: Tetrahydrofuran (Wako Pure Chemical Industries, Ltd.,
>99.5%) and chlorodimethylsilane (ClSiHMe2, Tokyo Kasei Co.,
>95.0%) were used for the synthesis of DMS-1. Hydrosilylation of
DMS-1 was conducted with 1-hexadecene (Wako Pure Chemical Indus-
tries, Ltd., >95.0%), triethoxyvinylsilane (Tokyo Kasei Co., >98.0%),
allyl-EG4 (synthesized according to the literature;[34] details are in the
Supporting Information), H2PtCl6·6H2O (Kanto Chemical Co., >98.5%),
acetonitrile (Wako Pure Chemical Industries, Ltd., >99.5%), and tolu-
ene (Wako Pure Chemical Industries, Ltd.,>99.5%). Chloroform (Wako
Pure Chemical Industries, Ltd., >99.0%) was used as an eluent in gel
permeation chromatography (GPC).
Synthesis of DMS-1: The synthesis procedure of DMS-1 was based on
our previous report on TMS-1.[11] Compound 1 (Scheme 1) was synthe-
sized according to a previous report.[23] Water (1.03 mL , 5.7ꢁ10À2 mol)
was added to a mixture of 1 (0.880 g, 4.76ꢁ10À4 mol), THF (11.6 mL,
0.142 mol), and chlorodimethylsilane (ClSiHMe2, 15.5 mL, 0.143 mol)
with vigorous stirring. Stirring of the mixture was continued for 30 min in
an ice bath. The molar ratio of 1/chlorodimethylsilane/THF/H2O was
1:300:300:120. The solvent, unreacted silylating agent, and (Me2HSi)2O
produced as a byproduct were removed under reduced pressure at 808C.
Then, white powder was obtained. Finally, the powder was dissolved in
chloroform and purified by GPC (eluent: chloroform) to obtain DMS-1.
The yield was 82%. DMS-1 was characterized by solution 1H, 13C, and
29Si NMR spectroscopy, solid-state 29Si MAS NMR spectroscopy,
MALDI-TOF MS, powder XRD, TG-DTA, TG-DTA-MS, and FTIR
spectroscopy (the details are shown in the Supporting Information).
[7] a) H. Mori, M. G. Lanzendçrfer, A. H. E. Mꢂller, J. E. Klee, Macro-
Q. Huo, Langmuir 2010, 26, 11421–11426.
[8] E. A. Rebrov, A. M. Muzafarov, V. S. Papkov, A. A. Zhdanov, Dokl.
Akad. Nauk SSSR 1989, 309, 376–380.
[9] a) H. Uchida, Y. Kabe, K. Yoshino, A. Kawamata, T. Tsumuraya, S.
39, 9369–9378; c) N. Auner, B. Ziemer, B. Herrschaft, W. Ziche, P.
Preparation of a DMS-1 cast film and its thermal treatment: A film was
prepared by casting a THF solution (100 mL, 1.23ꢁ10À6 mol) of DMS-1
(10.0 mg, 3.88ꢁ10À6 mol) on a Si substrate. The film was transparent
after drying. A heat-treated sample of the film was prepared by treat-
ment in an oven at 1808C under air for 5 days. The thermally treated film
was white and brittle, and was easily peeled off from the substrate. The
sample was pulverized for measurements by powder XRD, solid-state
29Si MAS NMR spectroscopy, FTIR spectroscopy, and N2 adsorption.
[11] K. Kawahara, Y. Hagiwara, A. Shimojima, K. Kuroda, J. Mater.
Hydrosilylation of DMS-1: A solution of H2PtCl6 (0.02m) in CH3CN
(16.6 mL) was added to a mixture of DMS-1 (0.200 g, 7.77ꢁ10À5 mol), 1-
hexadecene (1.26 g, 5.59ꢁ10À3 mol), and toluene (10 mL). The molar
ratio of DMS-1/1-hexadecene/H2PtCl6 was 1:72:2.2ꢁ10À3. The mixture
was stirred under N2 flow at 908C for 1 day and the volatile solution was
removed under reduced pressure to give a yellow viscous solution. The
solution was purified by GPC (eluent: chloroform) and the main compo-
nent (C16-DMS-1) was isolated. TES-DMS-1 and EG4-DMS-1 were also
synthesized with the same procedure by using triethoxyvinylsilane
(1.06 g, 5.59ꢁ10À3 mol) and allyl-EG4 (0.925 g, 3.73ꢁ10À3 mol,), respec-
tively. Their molar ratios were DMS-1/triethoxyvinylsilane/H2PtCl6 =
1:72:2.2ꢁ10À3 and DMS-1/allyl-EG4/H2PtCl6 =1:48:2.2ꢁ10À3. Hydrosily-
b) P.-A. Jaffrꢃs, R. E. Morris, J. Chem. Soc. Dalton Trans. 1998,
2767–2770; c) X. Zhang, K. J. Haxton, L. Ropartz, D. J. Cole-Hamil-
d) K. J. Haxton, D. J. Cole-Hamilton, R. E. Morris, Dalton Trans.
[13] a) D. Hoebbel, I. Pitsch, A. R. Grimmer, H. Jancke, W. Hiller, R. K.
Harris, Z. Chem. 1989, 29, 260–261; b) K. Saxena, C. S. Bisaria,
1
lated samples were characterized by solution H, 13C, and 29Si NMR spec-
[15] We investigated the reactivities of both ClSiHMe2 and ClSiMe3 with
troscopy.
HOSiPh3. HOSiPh3 was added to
a mixture of ClSiHMe2 and
ClSiMe3 with the same molar ratio. The 29Si NMR spectrum of
the crude sample mainly showed four signals due to a dimethyl-
silylated derivative (À19.6 ppm (Ph3SiOSiHMe2) and À3.3 ppm
(Ph3SiOSiHMe2)) and a trimethylsilylated derivative (À21.2 ppm
(Ph3SiOSiMe3) and 10.8 ppm (Ph3SiOSiMe3)) with integration ratios
of 1.0:1.0:0.30:0.25 (Supporting Information, Figure S1). The dime-
thylsilylated derivative was produced about four times more than
the trimethylsilylated derivative. This result indicates that the reac-
tivity of ClSiHMe2 is higher than that of ClSiMe3. The difference in
the reactivity is caused by the different degree of steric hindrance of
the reagents.
Acknowledgements
The authors are grateful to Dr. Toshimichi Shibue (MCCL, Waseda Uni-
versity) for TG-DTA-MS measurements and Prof. A. Shimojima (The
University of Tokyo), Mr. R. Wakabayashi (Waseda University), and Dr.
Y. Kuroda (Waseda University, now at The University of Tokyo) for
useful discussions. This work was supported in part by a Grant-in-Aid for
Scientific Research (No. 23245044), Elements Science and Technology
Chem. Eur. J. 2011, 17, 13188 – 13196
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13195