Dichlorosilane monomers, synthesis

Synthesis of enantioselective polysiloxanes comprises three main steps (a) synthesis of appropriately functionalized dichlorosilane monomers, (b) preparation of a fluid copolymer with a specified number of functional groups per weight unit and (c) covalent attachment of a suitable chiral enantio-selective moiety. 

The R1 values obtained for such phenylethynyl substituted siloxanes are higher then that reported for traditional aromatic-based systems [9] or the phenol modified ones (1.50-1.53) [10]. The synthesis of high refractive index (methyl)(diphenyle thenyl)-dichlorosilane via hydrosilylation was also described [1]. Such monomer was later hydrolyzed and condensed into silicone fluid. Similar process was also presented, applying silylative coupling process in the synthesis of an analogous (methyl)(phenylethenyl)diethoxysilane [11], so the two reactions shall be discussed in the following section. 

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