Trifluoromethanesulfonic acid trimethylsilyl triflate

CT3795 EINECS 248-5664 Methanesulfonio acid, trifluoro-, trimethylsilyl ester Trifluoromethanesulfonic acid trimethylsilyl ester Trimethylsilyl triflate Trimethylsilyl trifluoromethanesulfonate ... 

Trimethyls lyl triflate. See Trimethylsilyl trifluoromethane sulfonate Trimethylsilyl trifluoromethane sulfonate CAS 27607-77-8 EINECS/ELINCS 248-565-4 Synonyms Trifluoromethanesulfonic acid trimethylsilyl ester Trimethylsilyl triflate Trimethylsilyl trifluoromethyl sulfonate Classification Silane Empirical C4HgF303SSi Formula CF3S03Si(CH3)3... 

Trimethylsilyl trifluoromethanesulfonate (trimethylsilyl triflate) is the most synthetically useful representative of the family of trialkylsilyl perfluoroalkane-sulfonates (for a review, see reference 101) This reagent is commercially available or can be prepared easily by the reaction of chlorotrimethylsilane and triflic acid [101] It has wide application in organic synthesis as an excellent silylating reagent... 

Benzyne is an important reactive intermediate especially useful for the construction of polycyclic compounds via cycloaddition reactions with various dienes. Several benzyne precursors, including diphenyliodonium-2-carboxylate [ 1 ], have been previously used for the generation of benzyne by thermal decomposition. More recently, several new precursors that generate benzyne quantitatively under very mild conditions have been developed [105 -108]. An efficient benzyne precursor, iodonium triflate 109, can be readily prepared by the reaction of l,2-bis(trimethylsilyl)benzene 108 with [(diacetoxy)iodo]benzene in the presence of trifluoromethanesulfonic acid (Scheme 47) [105]. 

Review. This review covers not only trifluoromethanesulfonic acid (triflic acid), but also the anhydride, trimethylsilyl triflate, triflate salts, and alkyl and vinyl triflates (232 references). 

After the readily available Friedel-Crafts catalyst, tin(IV) chloride, had been established as a catalyst for nucleoside synthesis, several other new catalysts, such as trimethylsilyl triflate (trimethylsilyl trifluoromethanesulfonate TMSOTf), etc., which are less acidic as Lewis acids... 

To a solution of trifluoromethanesulfonic acid (1.5 g, 10 mmol) in dry dichloro-methane (8 mL), allyltrimethylsilane (1.6 g, 14 mmol) is added dropwise with stirring. The reaction temperature is maintained between 15 and 20 °C for 1 h. The resulting mixture is transferred directly to a distillation apparatus and distillation under reduced pressure gives trimethylsilyl triflate as a colorless liquid (1.9 g, 85 %), bp 52-53 °C/31 Torr NMR (CDCI3) d 0.50 ppm. 

As homogeneous acid catalysts, trifluoromethanesulfonic acid (CF3SO3H) and its silylated form, trimethylsilyl triflate (CF3S03SiMc3), were chosen for comparison of the acid catalysis between heterogeneous and homogeneous acids. The reaction of 14a with 15a or 15b proceeded smoothly even at low temperature in the presence of CF3S03SiMe3 as well as CF3SO3H (Table XIV, Entries 8, 10 Table XV, Entries 12, 13, 15). The catalytic behavior of... 

Phenyl) [2-(trimethylsilyl)phenyl]iodonium triflate lodonium, phenyl-, 2-(trimethylsilyl)-phenyl-, salt with trifluoromethanesulfonic acid (1 1) (13) (164594-13-2)... 

MMTS MsOH NBS NHMDS NMP NMR PPb Ph Pr PTC rt TBDMS Tf THF THP TLC TMEDA TMS TMSOTf Tol TOMAC Ts TsOH UDP methyl methylthiomethyl sulfoxide (=FAMSO) methanesulfonic acid N-bromosuccinimide sodium hexamethyldisililazide /V-methyl-2-pyrrolidone nuclear magnetic resonance parts per billion phenyl propyl Phase transfer catalysis room temperature t-butyldimethylsilyl triflatc (trifluoromethanesulfonate) tetrahydrofuran 2-tetrahydro-2//-pyran-2-yl thin-layer chromatography /V./V./V /V -tetramethylethylenediamine trimethylsilyl trimethylsilyl triflate p-tolyl trioctylmethylammonium chloride tosyl p-toluenesulfonic acid ultrasonically dispersed potassium... 

Trifluoromethanesulfonic acid (triflk ad Trimethylsilyl triflate. Admixture c or CO(NHSiMej)2 generates TMSOTf in si reactions. 

Electrophilic attack by aldehydes can also take place at positions 3 and 4 in suitably substituted thiophenes. Thus, 2,5-bis(trimethylsilyloxy)thiophene reacts with aromatic aldehydes in the presence of the Lewis acid trimethylsilyl trifluoromethanesulfonate (0.1-1.0%) to form 3,4-disubstituted thiosuccinic anhydrides (88) in quantitative yield. With aliphatic aldehydes, the yields are lower, the catalyst being ZnBry, the products so obtained have been hydrolyzed in the presence of lead acetate to form the lactones (89) in 30-40% yields. 2,5-Bis(trimethylsilyloxy)thiophene also reacts with orthoesters in the presence of trimethylsilyl triflate to form (90) <87C152,92LA615>. 

The efficient acylbenzyne precursors, [5-acyl-2-(trimethylsilyl)phenyl]iodonium triflates 705 have been prepared by reaction of the appropriate l,2-bis(trimethylsilyl)benzenes with PhI(OAc)2 in the presence of trifluoromethanesulfonic acid in dichloromethane at room temperature. Treatment of these reagents with BU4NF in dichloromethane generates acylbenzynes 706, which can be trapped by furan to give adducts 707 in high yield (Scheme 3.283) [927]. 

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