Synthesis of 1,3‐bis(2‐trimethylsilyloxyhexafluoro‐2‐propyl)‐5‐allylbenzene and its introduction into polysiloxane chains

Abstract

The synthesis of 1,3-bis(2-trimethylsilyloxyhexafluoro-2-propyl)-5-allylbenzene (IV) is described, starting from commercially available 1,3-bis(2-hydroxyhexafluoro-2-propyl)benzene. After the first step of iodination was optimized, a series of metallating agents were tested, before allylation, so that the best reagent could be selected. The allyl compound IV was then added to two different copoly(dimethylmethylhydro)siloxanes, PS 122.5 and PS 123 from Gelest/ABCR, via platinum-catalyzed hydrosilylation, for the preparation of new polysiloxanes bearing specifically designed pendant aryl moieties. The different synthesized products were characterized by spectroscopic methods (IR and 1 H, 13 C, 19 F, and 29 Si NMR), and the glass-transition temperatures of copolymers VI-2, VI-3, and VI-4 were measured. It was shown that the higher the amount was of grafted fluoroaryl groups, the higher the glass-transition temperature was.

Convenient syntheses of 1,1,1,3,3,3-hexafluoro-2-organyl-propan-2-ols and the corresponding trimethylsilyl ethers

“…in polysiloxane chains. 20 Therefore, the search for selective and efficient synthetic methods for 8 and related compounds can be regarded as one of considerable interest.…”

Bimetallic Combinations for Dehalogenative Metalation Involving Organic Compounds

“…Bu 3 MgLi was also found to be the reagent of choice for the synthesis of siloxane monomers, as reported by Guida-Pitrasanta’s group. The product depicted in Scheme was then successfully used in the synthesis of functional polysiloxanes …”