Siloxane‐Based Building Blocks for Molecular Technology

Copper‐Promoted Formation of Vinylsiloxanes

“…A conventional method for the synthesis of siloxane from chlorosilanes is hydrolysis promoting dehydrative condensation of the formed silanol intermediates. Since the reactivity of organochlorosilanes is much greater than that of allylsilanes or organohydrosilanes, that is why organochlorosilanes are used mainly as polysiloxane precursors or as surface modifiers . In addition, in the case of organodichloro– and organotrichlorosilanes, a spontaneous self‐condensation of silanols makes it difficult to control structurally well‐defined siloxane compounds.…”

“…Another disadvantage of most hydrolytic reactions is that a hydrogen chloride scavenger is required to shift the equilibration toward the desired siloxane, and the fact that time‐consuming, laborious step of phase separation must be carried out. In the last decades, non‐hydrolytic processes, including sol‐gel reactions, were found to be very efficient for precise design of siloxane‐based materials. Several types of cross‐coupling reactions of halosilanes with silanols, silanolates, or alkoxysilanes have been reported, but special emphasis must be placed on processes using an extraneous source of oxygen, such as ethers, air or dimethyl sulfoxide .…”

“…Demand for higher performance and higher functionality of siloxane compounds is increasing year by year, and there is a need for techniques capable of precisely controlling the main skeleton of organosilicon products. [1] Special attention is paid to vinyl siloxanes that are highly versatile substrates for a wide range of chemical modification reactions especially copolymerization and hydrosilylation. [2] Poly(vinylsiloxane) provides a flexible middle segment in the copolymers, while vinyl side group may be used as a cross-linker or chain extender.…”

“…Since the reactivity of organochlorosilanes is much greater than that of allylsilanes or organohydrosilanes, that is why organochlorosilanes are used mainly as polysiloxane precursors or as surface modifiers. [1] In addition, in the case of organodichloro-and organotrichlorosilanes, a spontaneous self-condensation of silanols makes it difficult to control structurally well-defined siloxane compounds. Another disadvantage of most hydrolytic reactions is that a hydrogen chloride scavenger is required to shift the equilibration toward the desired siloxane, and the fact that time-consuming, laborious step of phase separation must be carried out.…”

“…Another disadvantage of most hydrolytic reactions is that a hydrogen chloride scavenger is required to shift the equilibration toward the desired siloxane, and the fact that time-consuming, laborious step of phase separation must be carried out. In the last decades, non-hydrolytic processes, [1] including sol-gel reac-the process and alter the pathway of siloxanes formation employing Cu 2 O as the source of oxygen. It was also shown that acetonitrile may be available as a solvent for construction of the systems with large preparative capabilities, including those based on the use atmospheric oxygen in siloxane synthesis.…”