79271-56-0

Basic information

• Product Name: Triethylsilyl trifluoromethanesulfonate
• Synonyms: TES TRIFLATE;TRIFLUOROMETHANESULFONIC ACID TRIETHYLSILYL ESTER;TRIETHYLSILYL TRIFLATE;TRIETHYLSILYL TRIFLUOROMETHANESULFONATE;TRIETHYLSILYL TRIFLUOROMETHANESULPHONATE;1,1,1-TRIETHYLSILYL TRIFLUOROMETHANESULFONATE;TRIETHYLSILYL TRIFLUOROMETHANESULFONATE 99%;TES-OTF
• CAS NO: 79271-56-0
• Molecular Formula: C₇H₁₅F₃O₃SSi
• Molecular Weight: 264.34
• EINECS: 279-124-4
• Product Categories: Protection & Derivatization Reagents (for Synthesis);Si (Classes of Silicon Compounds);Silicon Compounds (for Synthesis);Silyl Esters;Si-O Compounds;Synthetic Organic Chemistry;metal triflate compounds
• Mol File: 79271-56-0.mol
• Article Data: 5

Chemical Properties

• Boiling Point: 85-86 °C12 mm Hg(lit.)
• Flash Point: 162 °F
• Appearance: Clear colorless to light brown/Fuming Liquid
• Density: 1.169 g/mL at 25 °C(lit.)
• Vapor Pressure: 0.327mmHg at 25°C
• Refractive Index: n20/D 1.389(lit.)
• Storage Temp.: Inert atmosphere,Room Temperature
• Solubility: Triethylsilyl Trifluoromethanesulfonate is readily sol hydrocarbons, dialkyl ethers, halogenated solvents. CH2Cl2 is employed most commonly. Reactions in 1,2-dichloroethane proceed faster than those in CCl4 or Et2O. Protic solvents and THF react with trialkylsilyl triflates and are therefore not suitable.
• Water Solubility: Miscible with dichloromethane, hydrocarbons, dialkyl ethers and halogenated solvents. Immiscible with water.
• Sensitive: Moisture Sensitive
• BRN: 3590541
• CAS DataBase Reference: Triethylsilyl trifluoromethanesulfonate(CAS DataBase Reference)
• NIST Chemistry Reference: Triethylsilyl trifluoromethanesulfonate(79271-56-0)
• EPA Substance Registry System: Triethylsilyl trifluoromethanesulfonate(79271-56-0)

Safety Data

• Hazard Codes: C,F
• Statements: 34-14
• Safety Statements: 26-36/37/39-45-27
• RIDADR: UN 3265 8/PG 2
• WGK Germany: 3
• F: 10-21
• TSCA: No
• HazardClass: 8
• PackingGroup: II
• Hazardous Substances Data: 79271-56-0(Hazardous Substances Data)

Usage

Description

Triethylsilyl trifluoromethanesulfonate, also known as triethylsilyl triflate (Et3SiOTf), is a chemical compound that serves as a potent silylating agent and a Lewis acid catalyst. It is characterized by its ability to protect alcohols as triethylsilyl ethers, which are more stable towards hydrolysis than trimethylsilyl ethers. This stability has led to its increasing use as a protecting group for alcohols in various chemical reactions.

Uses

Used in Chemical Synthesis:
Triethylsilyl trifluoromethanesulfonate is used as a silylating agent for the protection of alcohols during chemical synthesis. Its increased stability towards hydrolysis compared to trimethylsilyl ethers makes it a preferred choice for protecting sensitive alcohol groups.
Used as a Lewis Acid Catalyst:
In the capacity of a Lewis acid catalyst, triethylsilyl trifluoromethanesulfonate facilitates various condensation reactions, such as the reaction of 2-trimethylsiloxyfuran with aldehydes, leading to the formation of threo addition products.
Used in the Preparation of Diazo Compounds:
Triethylsilyl trifluoromethanesulfonate is utilized in the synthesis of 1-diazo-3,3-dimethyl-1-(triethylsilyl)-2-butanone from 1-diazo-3,3-dimethyl-butan-2-one, showcasing its versatility in organic chemistry.
Used in Overcoming Steric Hindrance:
In cases where steric hindrance prevents the silylation of hydroxyl groups using Et3SiCl, triethylsilyl trifluoromethanesulfonate is employed to effectively address this challenge, allowing for the successful protection of sterically hindered alcohols.

Preparation

Triethylsilyl Trifluoromethanesulfonate can be prepared by reacting chlorotriethylsilane with trifluoromethanesulfonic acid followed by distillation.

InChI:InChI=1/C7H15F3O3SSi/c1-4-15(5-2,6-3)13-14(11,12)7(8,9)10/h4-6H2,1-3H3

Upstream product

• 617-86-7 triethylsilane 
• 66469-45-2 Silantetrayltetrakis(trifluormethansulfonat) 
• 1493-13-6 trifluorormethanesulfonic acid 
• 994-30-9 triethylsilyl chloride 

Downstream Products

• 157808-69-0 (5R,6S)-3-(3-Nitro-phenyl)-7-oxo-6-((R)-1-triethylsilanyloxy-ethyl)-1-aza-bicyclo[3.2.0]hept-2-ene-2-carboxylic acid 4-nitro-benzyl ester 
• 114566-90-4 1-benzyl-3-(triethylsiloxy)azetidine 
• 157808-71-4 (5R,6S)-7-Oxo-6-((R)-1-triethylsilanyloxy-ethyl)-3-(4-trifluoromethyl-phenyl)-1-aza-bicyclo[3.2.0]hept-2-ene-2-carboxylic acid 4-nitro-benzyl ester 
• 128685-12-1 C₉₆H₁₇₁NO₁₈Si₄ 
• 126788-81-6 (E)-(2S,3S)-5-((1R,3R,4R)-3-Methoxy-4-triisopropylsilanyloxy-cyclohexyl)-2,4-dimethyl-3-triethylsilanyloxy-pent-4-enoic acid methoxy-methyl-amide 
• 131675-58-6 methyl 4-<<3-O-methyl-2,4-bis-O-(triethylsilyl)-α-L-rhamnopyranosyl>oxy>-5-iodo-2,3-dimethoxy-6-methylbenzoate 
• 126789-21-7 (S)-4-Benzyl-3-[(2S,3R)-2-(4-methoxy-benzyloxy)-4-methyl-3-triethylsilanyloxy-pentanoyl]-oxazolidin-2-one 
• 126789-40-0 (2S,3R,4R,6S,7R,8S,10R) 2-(p-Methoxybenzyloxy)-3-triethylsilyloxy-4,10-dimethyl-6,8-dimethoxy-7-t-butyldimethylsilyloxy-11-triisopropylsilyloxyundecanoic acid 
• 118977-94-9 C₈₈H₁₆₇NO₁₄Si₅ 
• 144668-41-7 C₁₀₂H₁₅₈IN₃O₂₄S₄Si₅ 
• 158574-41-5 (4R,5R,6S)-6-Methoxy-4-(4-methoxy-benzyloxy)-3,3-dimethyl-5-triethylsilanyloxy-7-[(4S,5S,6R)-2,2,5-trimethyl-6-((R)-1-methyl-2-trityloxy-ethyl)-[1,3]dioxan-4-yl]-heptan-2-one 
• 136758-70-8 Triethyl-((E)-1-isopropyl-4-phenyl-but-3-enyloxy)-silane 
• 136758-66-2 2,2-Dimethyl-propionic acid (E)-5-phenyl-2-triethylsilanyloxy-pent-4-enyl ester 
• 129986-29-4 <1R,1(1R),2S>-<<1-<1-<(4-methoxyphenyl)methoxy>ethyl>-2-methoxy-4-penten-1-yl>oxy>-1,1,1-triethylsilane 

Relevant articles and documents

Heterolytic activation of H-X (X = H, Si, B, and C) bonds: An experimental and theoretical investigation

The highly electrophilic, coordinatively unsaturated, 16-electron [Ru(P(OH)3)(dppe)2][OTf]2 (dppe = Ph 2PCH2CH2PPh2) complex 1 activates the H-H, the Si-H, and the B-H bonds, in H2(g), EtMe2SiH and Et3SiH, and H3B·L (L = PMe3, PPh3), respectively, in a heterolytic fashion. The heterolysis of H2 involves an η2-H2 complex (observable at low temperatures), whereas the computations indicate that those of the Si-H and the B-H bonds proceed through unobserved η1-species. The common ruthenium-containing product in these reactions is trans-[Ru(H)(P(OH) 3)(dppe)2][OTf], 2. The [Ru(P(OH)3)(dppe) 2][OTf]2 complex is unique with regard to activating the H-H, the Si-H, and the B-H bonds in a heterolytic manner. These reactions and the heterolytic activation of the C-H bond in methane by the model complex [Ru(POH)3)-(H2PCH2CH2PH 2)2][CI][OTf], 4, have been investigated using computational methods as well, at the B3LYP/ LANL2DZ level. While the model complex activates the H-H, the Si-H, and the B-H bonds in H2, SiH4, and H3B·L (L = PMe3, PPh 3), respectively, with a low barrier, activation of the C-H bond in CH4 involves a transition state of 57.5 kcal/mol high in energy. The inability of the ruthenium complex to activate CH4 is due to the undue stretching of the C-H bond needed at the transition state, in comparison to the other substrates.

Zinc-catalyzed silylation of terminal alkynes

(Chemical Equation Presented) A rapid and high-yielding silylation of terminal alkynes employing TMSOTf and catalytic quantities of Zn(OTf) 2 has been developed. The reaction works well for a variety of substrates including reactive esters. Fifteen examples with yields of >90% are reported.

Lewis acid mediated Peterson fluoroolefination

Peterson olefination of the alkyl and aryl aldehydes with C,O-bis(triethylsilyl)fluoroketene acetal 1 promoted by titanium tetrachloride and dimethylaluminum chloride was investigated. Desired fluoroolefins were formed with high stereoselectivity and moderate to high yields.