Synthesis of Novel Titanasiloxanes with Ring and Cage Structures Using Sterically Demanding Substituents
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- 作者：Jö ; rn-Oliver Nolte ; Manuela Schneider ; Beate Neumann ; Hans-Georg Stammler ; and Peter Jutzi
- 刊名：Organometallics
- 出版年：2003
- 出版时间：March 3, 2003
- 年：2003
- 卷：22
- 期：5
- 页码：1010 - 1017
- 全文大小：209K
- 年卷期：v.22,no.5(March 3, 2003)
- ISSN：1520-6041
文摘
Novel oligomeric titanasiloxanes have been synthesized in good yields by reaction ofsterically demanding organosilanetriols with titanium alkoxides. The silanetriols tBu2(Me3Si)FlSi(OH)3 (5), (Me3Si)FlSi(OH)3 (6), and MeFlSi(OH)3 (7) and the titanium alkoxides Ti(OEt)4, Ti(OiPr)4, and Ti(OiPr)2(acac)2 have been used as starting materials (Fl = fluorenyl).Quite different structures are obtained by only small modifications of the organic substituentsof the substrates. Thus, the condensation reactions result in the formation of the polyhedraltitanasiloxanes [tBu2(Me3Si)FlSi]4O12[TiOEt]4 (8), [(Me3Si)FlSi]2O5[Ti(OEt)]4[
2-OEt]6[4-O](9), ([tBu2(Me3Si)FlSi]3O10[Ti(OiPr)]4[2-OiPr]2[3-O]Ti)2O (10), and [MeFlSi]2O8[Ti(OiPr)]6[2-OiPr]4[3-O]2[PhNH2]2 (11) and the cyclic titanasiloxane [MeFlSi(OiPr)]2O4[Ti(acac)2]2 (12).A 1:1 stoichiometry of the starting materials leads to 8 and 12 in quantitative yield, while9-11 are isolated in minor quantities. If the appropriate substrate ratio is used, the lattercompounds can also be obtained in high yields. All titanasiloxanes have been characterizedby X-ray crystallography, NMR, IR, and elemental analysis.
2-OEt]6[4-O](9), ([tBu2(Me3Si)FlSi]3O10[Ti(OiPr)]4[2-OiPr]2[3-O]Ti)2O (10), and [MeFlSi]2O8[Ti(OiPr)]6[2-OiPr]4[3-O]2[PhNH2]2 (11) and the cyclic titanasiloxane [MeFlSi(OiPr)]2O4[Ti(acac)2]2 (12).A 1:1 stoichiometry of the starting materials leads to 8 and 12 in quantitative yield, while9-11 are isolated in minor quantities. If the appropriate substrate ratio is used, the lattercompounds can also be obtained in high yields. All titanasiloxanes have been characterizedby X-ray crystallography, NMR, IR, and elemental analysis.