Triisopropylsilyl Trifluoromethanesulfonate

Chemical properties

clear light brown to orange-brown liquid

Physical properties

Colorless oil; bp 83–87 °C/1.7 mmHg; d 1.173 g cm?3.

The Uses of Triisopropylsilyl Trifluoromethanesulfonate

Triisopropylsilyl Trifluoromethanesulfonate is a highly reactive silylating agent and Lewis acid capable of converting primary and secondary alcohols to the corresponding triisopropylsilyl ethers and converting ketones and lactones into their enol silyl ethers; protection of terminal alkynes; promoting conjugate addition of alkynylzinc compounds to α,β-enones; preparation of (triisopropylsilyl)diazomethane, participating in the following (but not limited to) reactions: Silylation of Alcohols, Formations of Enol Silyl Ethers, Alkynyltriisopropylsilanes, Conjugate Addition of Alkynylzinc Bromides, (Triisopropylsilyl)diazomethane, Triisopropylsiloxycarbonyl (Tsoc) and BIPSOP Protecting Groups for Amines, TIPS Protection for Oxazoles/Regioselective Trapping of C-2 Oxazole Anions, Benzannulation Using Triisopropylsilyl Vinyl Ketenes, Cyclization of 1-Silyloxy-1,5-diynes, Desymmetrization of Tartaric Acid Esters etc.

The Uses of Triisopropylsilyl Trifluoromethanesulfonate

Triisopropylsilyl trifluoromethanesulfonate is used as a reagent for the introduction of triisopropylsilyl(TIPS) group in organic synthesis. It is involved in the synthesis of 2-substituted benzothiopyran-4-ones and silyloxy acetylenes. As a protecting group in organic synthesis, it is utilized especially for the protection of primary amines. Furthermore, it plays an important role in Takahashi Taxol total synthesis or for chemical glycosylation reactions.

Preparation

To 38.2 g (0.242 mol) of triisopropylsilane at 0°C under argon is added 23.8 mL (0.266 mol) of trifluoromethanesulfonic acid dropwise. The solution is stirred at 22°C for 16 h, at which time no further hydrogen gas evolves (removed through a bubbler). The resulting product is distilled through a 30-cm vacuum jacketed Vigreux column under reduced pressure: 71.7 g (97% yield) of TIPS triflate; bp 83–87°C/1.7 mmHg.