Keteneiminium salt

Keywords Viehe salt, pyrocatechol, solid-solid reaction, keteneiminium salt... 

Ketemimimum trifSates cyclobutanones. Triflic anhydride converts tertiary amides mainly into the salt (1), which loses triflic acid in the presence of collidine to form the keteneiminium salt 2. When generated in the presence of alkenes or alkynes, 2 undergoes [2 + 2] c ycloaddition to form cyclobutanones or cyclobutenones, respectively.1... 

The advantage of this route to keteneiminium salts over the earlier route from a-halo enamines (4, 94-95 5,136-138) is that R1, and even R1 and R2, can be H. 

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See also in sourсe #XX -- [ ]

See also in sourсe #XX -- [ ]

See also in sourсe #XX -- [ ]

See also in sourсe #XX -- [ ]

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