Protection trifluoromethanesulfonic anhydride

The C-4 acids (183 and 184) have also been subjected to borane reduction conditions to afford alcohol 195 in 23-50% yield or 64% yield as the C-8 epimeric mixture (195 and 196, Scheme 29) [34, 49, 64]. The C-8 alcohol epimers 195 and 196 have been treated separately as a common intermediate for a number of C-4 derivatives including esters, ethers, and amines [34, 49, 64], Alcohols 195 and 196 was subjected to DCC, DMAP, and desired acid chloride or carboxylic acid in CH2CI2 affording ester analogs in 50-92% yield [64], Esters prepared include alkyl, aryl, and fluorenylmethyloxycarbonyl (Fmoc) protected amino acid derivatives (197 and 198) [64]. Ethers were prepared with various alkyl halides and Ag20 in CH3CN at 40 °C. Alkyl, allyl, and benzyl ethers were prepared in 45-80% yield (199 and 200) [34,64]. Alcohols 195 and 196 were then activated to the triflates and displaced by a variety of amines by treatment with trifluoromethanesulfonic anhydride and desired amine in 22% - quantitative yield over two steps (201 and 202)... 

Tetrazoles are usually prepared by the reaction of an azide with a nitrile, or an activated amide tri-n-butyltin azide and trimethylsilyl azide are more convenient and safer reagents than azide anion is some cases. The second example shown illustrates the use of a cyanoethyl group as a removable protecting group for amide nitrogen. Other variations on this method from nitriles include the use of triethylammonium chloride (instead of ammonium chloride) to avoid the possible sublimation of potentially explosive azides, and the use of micelles as reaction media. Amides can be activated with trifluoromethanesulfonic anhydride, or via formation of the thioamide, or by the use of triphenylphosphine with diethyl azodicarboxylate the equivalent imidochloride will react under phase transfer conditions. ... 

Tosyl-protected dipeptide loaded Wang resin 299 was prepared and treated with 3 equiv of PhaPO and 1.5 equiv of trifluoromethanesulfonic anhydride in DCM for 4h and then oxidized with 2.6 equiv of DBU (l,8-diazabicyclo[5.4.0]undec-7-ene) and 2.2 equiv of... 

Aniline allowed to react at -78° with trifluoromethanesulfonic acid anhydride and triethylamine in methylene diloride -> N-phenyltriflamide. Y 97%. - The protective group can be removed by reduction. F. e. and triflating agent, also Gabriel-type synthesis of prim, amines from halides via triflamides, s. J. B. Hendrickson and R. Bergeron, Tetrah. Let. 1973, 3839. 

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