ABSTRACT 1,2- and 1,3-diols can be protected synchronously by the 1,1,3,3-tetraisopropyl-1,3-disiloxane-diyl (TIPS) group. The TIPS group can be introduced by treating the diol with TIPS dichloride or bistrifluoromethanesulfonate. Both reagents are obtained conveniently from trichlorosilane and isopropyl-Grignard. The TIPS protective group is stable to slightly acidic and basic conditions, reductive and oxidative conditions and thus, compatible to a wide range of orthogonal sets of blocking groups. The TIPS group is removed selectively either by fluorodesilylation or by treatment with Lewis acids. Furthermore, cyclic TIPS-protected diols can be opened regioselectively by treatment with sodium hydroxide or hydrogen fluoride. Applications of the TIPS group in the synthesis of nucleosides, various natural products and mono- and oligosaccharides will be discussed. Novel developments for the application of TIPS-protected sugars, like the glycodesilylation protocol will be described.
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