Trifluoromethyl iminium salts

While further studies and the discussion are planned to be published elsewhere, it can be concluded that trifluorothioacetamides, their amidium salts, their amide chlorides, their thioacetals and 1,3-dipoles are useful reagents with CF3-substitution. The trifluoromethyl iminium salts, the trifluoroethyl-t-butyl sulfoxide, and the already mentioned trifluoro-dithioacetates are treated in the following sections. 

Platts and Tomkinson reported a detailed quantitative study of the iminium ion catalysed Diels-Alder reaction between cyclopentadiene and cinnamaldehyde catalysed by trifluoromethyl pyrrolidine salt 182-HPFg [227]. This combination of secondary amine, co-acid and dienophile allowed the isolation and structural elucidation of the reactive iminium ion intermediate. As a result it was possible to... 

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