Preparation and termination of carbosilane dendrimers based on a siloxane tetramer as a core molecule: silane arborols, part VIII
摘要:
Starting with 2,4,6,8-tetramethyl-2,4,6,8-tetravinyl-2,4,6,8-tetrasila-1,3,5,7-tetraoxacyclooctane (Me(CH2=CH)SiO)(4) as a core molecule, a succession of alternate platinum-catalyzed hydrosilations of all vinyl groups with HSiMeCl2,, as well as alkenylation with allylmagnesium bromide, provided the third generation (G3) as divergent growth of siloxane-based dendrimers. The reaction path of the repetitive allylation/hydrosilation cycles is controlled with NMR spectroscopic analyses. Each of the two steps provided quantitative yields of pure dendrimers. We also changed the simple construction of the G3P molecule into materials with special functions, such as by adding phenylethynyl and p-bromophenoxy groups on its periphery. (C) 1997 Elsevier Science S.A.
Preparation and termination of carbosilane dendrimers based on a siloxane tetramer as a core molecule: silane arborols, part VIII
摘要:
Starting with 2,4,6,8-tetramethyl-2,4,6,8-tetravinyl-2,4,6,8-tetrasila-1,3,5,7-tetraoxacyclooctane (Me(CH2=CH)SiO)(4) as a core molecule, a succession of alternate platinum-catalyzed hydrosilations of all vinyl groups with HSiMeCl2,, as well as alkenylation with allylmagnesium bromide, provided the third generation (G3) as divergent growth of siloxane-based dendrimers. The reaction path of the repetitive allylation/hydrosilation cycles is controlled with NMR spectroscopic analyses. Each of the two steps provided quantitative yields of pure dendrimers. We also changed the simple construction of the G3P molecule into materials with special functions, such as by adding phenylethynyl and p-bromophenoxy groups on its periphery. (C) 1997 Elsevier Science S.A.
Dendritic carbosilanes containing hydroxy groups on the periphery
作者:Chungkyun Kim、Sungmo Son、Bohyun Kim
DOI:10.1016/s0022-328x(99)00335-6
日期:1999.10
Dendritic carbosilanes with hydroxygroups on the periphery have been prepared. The hydroxy-group-containing dendrimers were prepared by the use of the hydroboration of carbosilane dendrimers containing double bonds with 9-BBN and the subsequent oxidation of the prepared dendrimers. Oxidation of the hydroborated dendrimers in an alkali medium gave quantitative yields. The hydroboration and oxidation
Preparation of dendritic carbosilanes containing ethynyl groups and dicobalt hexacarbonyl clusters on the periphery
作者:Chungkyun Kim、Inkyung Jung
DOI:10.1016/s0022-328x(99)00336-8
日期:1999.10
Dendritic carbosilanes have been prepared by the use of 2,4,6,8-tetramethyl-2,4,6,8-tetravinyl-2,4,6,8-tetrasila-1,3,5,7-tetraoxacyclooctane (CH2=CHMeSiO), and 1,2-bis(triallylsilyl)ethane ((CH2=CHCH2)(3)SiCH2)(2) as core molecules, diallylmethylsilyl groups ((CH2=CHCH2)(2)MeSi-) as building blocks and bisphenylethynylmethylsilyl groups ((PhC=C)(2)MeSi-) as terminating groups. The phenylethynyl-group-containing terminal generation is produced by the reaction of the chlorosilylated generation with lithium phenylacethylide. The reaction of dicobalt octacarbonyl Co,(CO), with phenylethynyl groups gave the corresponding phenylethynyl hexacarbonyl complexes (2Co(2)(CO)(6).(PhC=C)(2)MeSi-dendimer) on the periphery. The yields of the prepared dendrimers with phenylethynyl terminal groups and their cobalt carbonyl complexes are obtained nearly quantitatively. They are characterized by the use of spectroscopic analyses (H-1-, and C-13-NMR, UV and IR) as well as MALDI mass spectroscopy and elemental analysis. (C) 1999 Elsevier Science S.A. All rights reserved.