Synthesis of Polycyclic and Cage Siloxanes by Hydrolysis and Intramolecular Condensation of Alkoxysilylated Cyclosiloxanes
| Autor: | Atsushi Shimojima, Kazuyuki Kuroda, Hiroaki Wada, Tomoaki Sugiyama, Masashi Yoshikawa, Hiroya Shiba |
|---|---|
| Rok vydání: | 2018 |
| Předmět: |
biology
010405 organic chemistry Organic Chemistry Condensation General Chemistry 010402 general chemistry Condensation reaction biology.organism_classification 01 natural sciences Catalysis 0104 chemical sciences Nanomaterials chemistry.chemical_compound Hydrolysis Monomer chemistry Siloxane Intramolecular force Polymer chemistry Tetra |
| Zdroj: | Chemistry (Weinheim an der Bergstrasse, Germany). 25(11) |
| ISSN: | 1521-3765 |
| Popis: | The controlled synthesis of oligosiloxanes with well-defined structures is important for the bottom-up design of siloxane-based nanomaterials. This work reports the synthesis of various polycyclic and cage siloxanes by the hydrolysis and intramolecular condensation of monocyclic tetra- and hexasiloxanes functionalized with various alkoxysilyl groups. An investigation of monoalkoxysilylated cyclosiloxanes revealed that intramolecular condensation occurred preferentially between adjacent alkoxysilyl groups to form new tetrasiloxane rings. The study of dialkoxy- and trialkoxysilylated cyclotetrasiloxanes revealed multistep intramolecular condensation reactions to form cubic octasiloxanes in relatively high yields. Unlike conventional methods starting from organosilane monomers, intramolecular condensation enables the introduction of different organic substituents in controlled arrangements. So-called Janus cubes have been successfully obtained, that is, Ph4 R4 Si8 O12 , in which R=Me, OSiMe3 , and OSiMe2 Vi (Vi=vinyl). These findings will enable the creation of siloxane-based materials with diverse functions. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Plný text