Synthesis and Chemistry of Cyclic and Acyclic Polyfluorosiloxanes of 2,2,3,3,-

摘要

The stability and strength of silicon-oxygen bonds (approx. 106 kcal/ mol) arewell-known in organic as well as inorganic synthetic chemistry, and these properties are used fully in the versatile practical applications of siloxanes. The use of siloxane functional groups as protecting groups as well as their role in forming stable volatile side products in chemical reactions (e.g., Me3SiOSiMe3, CF3CH2OSiMe3) is also well documented. A closer look at the literature reveals that reactions involving cleavage of a Si-O bond are rather scarce in contrast to the plethora of reactions reported on breaking of Si-X (X = Cl, Br, I), Si-N, Si-S and Si-C bonds. Frequently, Si-O bond breakage requires extreme reaction conditions or highly reactive reagents like strong acids or metal halides. However, they do break under rather mild conditions such those observed in the reactions of silyl enol ethers and in some reactions with compounds having P-F, S-F, M-F, and C-F bonds. (jg) p. 2.