Chlorides trifluoromethanesulfonyl

Vasella, A. Witzig, C. Chiara, J.-L. Martin-Lomas, M., Helv. Chlm. Actal991, 742073. 

Alvarez, R. M. S. Cutin, E. H. Romano, R. M. Mack, H.-G. Della Vedova, C. O., Spectmchlm. Acta, Part A, Molec. Blomolec. Spectrosc. 

Preparative Methods dried zinc trifluoromethanesulfonate is heated with PCl5-2ZnCl at 260 °C. Fractional distillation of the volatile products gives TfCl (94% yield).  

Handling, Storage, and Precautions moisture sensitive store under N2 in the cold. This toxic reagent is corrosive and is a lachrymator. It should only be handled in a fume hood. 

Paul A. Wender Thomas E. Smith Stanford University, Stanford, CA, USA 

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The chloride of triflic acid (trifluoromethanesulfonyl chloride) is an effective sulfonylating agent Like triflic anhydride, it usually reacts with alcohols and other nucleophiles with the formation of the corresponding derivatives of tnflic acid [69] However, in some reactions, it acts as a chlorinating reagent [98] The reactions of tnfluoromethanesulfonyl chloride with 1,3-dicarbonyl compounds or some carboxylic esters in the presence of a base result m the formation of chlonnated products in high yields (equation 49)... 

There are also procedures in which the enolate is generated and allowed to react with a halogenating agent. Among the sources of halogen that have been used under these conditions are bromine,91 A -chlorosuccinimide,92 trifluoromethanesulfonyl chloride,93 and hexachloroethane.94... 

This reaction has been carried out in DMAC for the trifluoromethylation of activated aryl chlorides such as 2,4-dinitro-l-chlorobenzene [95-97]. Similar trifluoromethylation can be accomplished with trifluoromethylcopper generated from trifluoromethanesulfonyl chloride and copper powder in DMAC [98] (Scheme 33). 

A significant feature in the synthesis of 2,2-disubstituted tetrahydropyrans from diethyl malonate is the selective chlorination by trifluoromethanesulfonyl chloride of carbanions which can be formed using triethylamine or DBU as the base (79TL3645). Monoalkylation of the diester with l-bromo-4-tetrahydropyranyloxybutane leads to the alcohol (237 R = H)... 

RuCl2(PPh3)3 catalyzes also the addition of trichloromethylsulfonyl chloride (and of simple sulfonyl chlorides683) to olefins which proceeds with extrusion of S02, resulting in the same products obtained with CC14684. (Note, however, that this reaction takes place even in the absence of catalyst685.) Trifluoromethanesulfonyl chloride behaves similarly (equation 92)686 ... 

CHLORINATION Bis(benzonitrile)dichloro-palladium(n). N-Chlorosucdnimide-Benzeneselenenyl chluride. N,N-Di-chlorouiethane. lodobenzene dichloride. Trifluoromethanesulfonyl chloride. 

Trifluoroethyl p-toluenesulfonate, 166 Trifluoromethanesulfonic acid, 485 Trifluoromethanesulfonyl chloride, 485 (Trinuotomethanesulfonylmethyl)trimethyl-... 

A substituent which appears to be even more readily displaced by nucleophiles than alkylsulfonyl groups is 0-mesyl (OSO CH ). Conversion of a cyclic lactam to its 0-mesyl derivative is accomplished by treatment with methanesulfonyl chloride/Et N in methylene chloride solution displacement takes place readily with dlmethylamine (15 min at 20 in dioxane). This may prove to be a generally useful procedure for replacement of lactam oxygen by other nucleophiles without resorting to intermediate chloro compounds. Note that 2-trlfluoromethanesulfonyloxypyridlne (from 2(lH)-pyridone, NaH, and trifluoromethanesulfonyl chloride) is an effective reagent for cile acylation of activated aromatic compounds with carboxylic acids. 

Trifluoromethanesulfonyl azide, prepared in situ from trifluoromethanesulfonyl chloride and sodium azide in dimethylformamide, is reported to azidate phospho-noacetic esters and p-dicarbonyl compounds in the presence of triethylamine,309 whereas the same, but preformed, reagent gives the diazo compounds with a-nitro328 and a-cyano329 carbonyl compounds in the presence of pyridine. The reason for this dichotomy is not clear but because the former reaction was carried out under typical diazo transfer conditions the products may have been misidentified.330... 

We also investigated the cycloaddition of a cyclopentenyl oxyallylic zwitterion derived from a chloroketone that contained the same tethered diene. The chlorination of ketone 48 at the less substituted a-position was accomplished by treatment with LDA and trifluoromethanesulfonyl chloride. The crude product was then treated with sodium trifluoro-... 

In the 4+3 cycloaddition step, ketone 58 was treated with LDA and the resultant enolate was quenched with trifluoromethanesulfonyl chloride at low temperature to give an a-chloroketone. This was not characterized... 

Trifluoromethanesulfonyl chloride is produced by (a) the reaction of trifluoromethanesulfonic acid with phosphorus pentachloride at 100°, (b) the reaction of trifluoromethanesulfenyl chloride, CF3SC1, with an excess of chlorine in the presence of water (Haszeldine and Kidd, 1955, 140 see also 29 and 116). 

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