Trifluoromethanesulfonic acid tert-butyldimethylsilyl ester

Description

tert-Butyldimethylsilyl trifluoromethanesulfonate (TBS-OTf) is generally used as a reagent for installing TBS protecting groups. A similar reagent is tert-butyldimethylsilyl chloride (TBS-Cl).

Chemical properties

clear colorless to yellow fuming liquid

Physical properties

bp 60°C/7 mmHg; colorless oil, d 1.151 g cm?3. Solubility: sol most organic solvents such as pentane, CH2Cl2, etc.

The Uses of Trifluoromethanesulfonic acid tert-butyldimethylsilyl ester

TrifluoroMethanesulfonic acid tert-butyldiMethylsilyl ester is a highly reactive silylating agent and lewis acid capable of converting primary, secondary and tertiary alcohols to their respectctive TBDMS. TrifluoroMethanesulfonic acid tert-butyldiMethylsilyl ester is also used to covert ketones and lactones into their enol silyl ethers.

The Uses of Trifluoromethanesulfonic acid tert-butyldimethylsilyl ester

A mixture of the SM (2.0 g, 10.0 mmol), 2,6-lutidine (2.13 g, 19.9 mmol), TBSOTf (3.1 g, 14.9 mmol), and DCM (30 mL) was stirred at RT for 2 h. The reaction mixture was quenched with H2O (20 mL), then extracted with DCM. The org layer was dried (Na2SO4) and concentrated. The crude residue was purified by silica gel chromatography (20:1 petroleum ether/EtOAc) to provide the product as a colorless oil.

The Uses of Trifluoromethanesulfonic acid tert-butyldimethylsilyl ester

t-Butyldimethylsilyl Trifluoromethanesulfonate is used as a highly reactive silylating agent and Lewis acid capable of converting primary, secondary, and tertiary alcohols1b to the corresponding TBDMS ethers, and converting ketones and lactones, into their enol silyl ethers; promoting conjugate addition of alkynylzinc compounds and triphenylphosphine5 to α,β-enones; activation of chromones in [4 + 2] cycloaddition reactions;rearrangement of allylic tributylstannyl silyl ethers; activation of pyridine rings toward Grignard reagents and transalkylation of tertiary amine N-oxides;and transformation of N-t-butoxycarbonyl groups into N-alkoxycarbonyl groups.

The Uses of Trifluoromethanesulfonic acid tert-butyldimethylsilyl ester

tert-Butyldimethylsilyl trifluoromethanesulfonate is involved in the introduction of a bulky tert-butyl dimethylsilyl group onto a cis-bis(alkenyl)oxirane used in Cope rearrangement. It is associated with a thiolane and promotes the chalcogenide-Morita-Baylis-Hillman reaction. Further, it is used as a highly reactive silylating agent. In addition to this, it is used to prepare enol silyl ethers by reacting with ketones and lactones.

Preparation

to 24 g (0.16 mol) of t-butyldimethylchlorosilane at 23°C under argon is added 14 mL (0.16 mol) of trifluoromethanesulfonic acid dropwise. The solution is heated at 60°C for 10 h, at which time no further hydrogen chloride evolves (removed through a bubbler). The resulting product is distilled under reduced pressure: 34 g (80% yield) of TBDMS triflate; bp 60°C/7 mmHg.