Alkylating agents trifluoromethanesulfonic

Gramstad, T. and Haszeldine, R.N., Perfluoroalkyl derivatives of sulfur. VII. Alkyl trifluoromethane-suRonates as alkylating agents, trifluoromethanesulfonic anhydride as a promoter for esterification, and some reactions of trifluoromethanesulfonic acid, J. Chem. Soc., 4069,1957. 

Ethyl trifluoromethanesulfonate [425-75-2] M 178.1, b 115 /atm, 118-120 /atm, d 1.378, Hp 1.336. The ester reacts slowly with H2O and aqueous alkali. If its IR has no OH bands (-3000 cm" ) then purify by redistillation. If OH bands are present then dilute with dry Et20 and shake (carefully) with aqueous NaHC03 until effervescence ceases, then wash with H2O and dry (MgSOa), filter, evaporate and distil the residue under slight vacuum then at atmospheric pressure in a N2 atmosphere. IT IS A POWERFUL ALKYLATING AGENT, AND THE FUMES ARE VERY TOXIC - CARRY ALL OPERATIONS IN AN EFFICIENT FUME CUPBOARD. [Gramstad and Hazeldine J Chem Soc 173 7956 Howells and McCown Chem Rev 77 69 1977.]... 

Oxetanes have also been used as alkylating agents in the Friedel-Crafts reaction for example, 2-isopropyloxetane was reacted with benzene in superacidic trifluoromethanesulfonic acid (TFSA) to give a mixture of alkylated aromatic products (Equation 9) <2003CAL1>. The main product of the reaction was the tetralin derivative 46 which could be isolated in up to 75% yield. Other notable side products are shown, resulting from monoalkylation or other skeletal rearrangements. 

Esters of very strong protonic acids (trifluoromethanesulfonic, fluoro-sulfonic, perchloric), however, are sufficiently strong alkylating agents to initiate the polymerization of even weakly nucleophilic monomers (cyclic acetals, ethers) [2-6], Also their anhydrides (e.g., triflic anhydride) are efficient initiators. This last compound is especially interesting, because in the polymerization of cyclic ethers it leads to macromolecules with two identical growing chain ends (difunctional initiator) [30] ... 

The third and final general protocol for the hydrolysis of 5 5-acetals exploits the very easy reaction of the sulfur atom of an 5-acetal with alkylating agents such as iodomethane. trimethyl- or triethyl-oxonium tetrafluoroborate. and methyl trifluoromethanesulfonate to form the corresponding trialkylsulfonium salts. Ley s approach to the potent insect antifeedant Azadirachtin [Scheme... 

In place of methyl trifluoromethanesulfonate. the checkers used triethyloxonium tetrafluoro-borate, obtained from Lancaster Synthesis Inc., as the alkylating agent. 

The trifluoromethanesulfonates have certain advantages over perchlorates (nonexplosive) and tetrafluoroborates (even less reactive toward oxidizing agents) [447]. The tetraalky-lammonium trifluoromethanesulfonates are just as soluble or more soluble in the commonly used organic solvents than the corresponding perchlorates or fluoroborates. They can be prepared either by metathesis or by alkylation of a tertiary amine by an ester of trifluoromethanesulfonic acid. 

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