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Polymerization of 1,2-anhydro-3,4,6-tri-O-benzyl-beta-D-mannopyranose under acid catalysis has led to a series of polymers varying in anomeric configuration from approximately 90% alpha to 70% beta. Optical rotations follow 13C-n.m.r. estimates of anomeric composition linearly over this range. Low-temperature polymerization with trifluoromethanesulfonic anhydride as initiator favors mainly cis-opening of the anhydro ring, presumably through the intermediary of a macroester. These results are compared with related glycosylation and polymerization reactions on 1,2-anhydro sugar derivatives, and some mechanistic conclusions are proposed.

The reactions of S-methyl thiobenzoate with methyl triflate and methyl fluorosulfate yielded benzoic trifluoromethanesulfonic anhydride and benzoyldimethylsulfonium ion, respectively. Both of these reactive intermediates were found to function as powerful benzoylating agents for an arene, amine, alcohol, and phenol.

A new practical method for diastereoconversion of 2-amino alcohols was performed by treatment of N-Cbz- derivatives with trifluoromethanesulfonic anhydride or thionyl chloride, followed by ring cleavage of the resulting oxazolidin-2-ones

Sulfinyl β- d -galactofuranosides 3( R , S ) and 9( R , S ) were used as new hexofuranosyl donors in glycosylation reactions. Activation by trifluoromethanesulfonic anhydride involved different reaction pathways depending on the stereochemistry at the sulfur atom. Experimental results underlined a more suitable reactivity of 3( R ) and 9( R ) versus 3( S ) and 9( S ) , respectively, for the synthesis of β- d -galactofuranosides.

The 18F-labeling of 5-(trifluoromethyl)-dibenzothiophenium trifluoromethanesulfonate, commonly referred to as the Umemoto reagent, has been accomplished applying a halogen exchange 18F-fluorination with 18F-fluoride, followed by oxidative cyclization with Oxone and trifluoromethanesulfonic anhydride. This new 18F-reagent allows for the direct chemoselective 18F-labeling of unmodified peptides at the thiol cysteine residue.

2H-Cyclohepta[b]furan-2-one (1) reacted with TPT, electrophilically to give 3-dihydropyridinyl-2H-cyclohepta[b]furan-2-one and subsequent treatment with sodium hydroxide in ethanol gave 3-(4-pyridinyl)-2H-cyclohepta[b]furan-2-one in excellent yields. Furthermore, it reacted with methyl iodide give a corresponding pyridinium salt easily., Article, Heterocycles. Vol 69, Issue 1, 2006, pp.119-122.

The reaction of alkyl and aryl α-halomethyl ketones 1 with aliphatic and aromatic nitriles 2 in the presence of trifluoromethanesulfonic anhydride affords substituted 5-halopyrimidines 3 in good yields (55-91%)

As the first exo-methylene analog of sydnone, the title compound was synthesized by the treatment of 3-phenylsydnone with trifluoromethanesulfonic anhydride followed by the reaction with malononitrile-triethylamine. The electronic structure is discussed on the basis of the spectroscopic evidences.

Cyclisation en presence de l'anhydride triflique des bis-dimethylamides des acides succinique, glutarique et adipique: obtention des perhydro furannediylium-2,5, -pyrannediylium-2,6 et -oxepinnediylium-2,7 disubstitues sur les carbeniums par dimethylamino

It has generally proven difficult to synthesize ribonucleosides with sugar modifications at the 3′ position. We now present a practical route for the synthesis of ribonucleosides with a 3′ fluorine substituent. Nucleosides with the xylo configuration were prepared by sugar-base condensation. Tritylation of the unprotected nucleosides gave a mixture of 2′,5′ and 3′,5′ bistritylated nucleosides which were difficult to characterize. Therefore the necessary precursors were synthesized in a step-wise fashion, starting with selective deprotection of the 2′-acyl group, followed by tritylation. This gave the 2′,5′-tritylated xylonucleosides in good yield. Reaction with diethylaminosulfur trifluoride and deprotection with 80 % acetic acid provided the 3′-fluoro-3′-deoxyribonucleosides 1, 2 and 4. The cytidine derivative was synthesized from 1 by reaction with trifluoromethanesulfonic anhydride followed by ammonia. Treatment of 4 with adenosine deaminase yielded 5.

A new approach for the synthesis of some sugar nitrates is described. The reaction sequence consists of esterifying partially protected carbohydrates with trifluoromethanesulfonic anhydride and reacting the resulting triflates with tetrabutylammonium nitrate. This procedure is mild, convenient and has the advantage of protecting highly acid-labile groups.