Trifluoromethanesulfonic Anhydride reaction with amines

Electrocyclization is the key step in a route to 4//-imidazoles 1187 and imidazoles 1188. Thus, activation of AT-acylamidines 1183 with trifluoromethanesulfonic anhydride and subsequent condensation with amino compounds 1185 produces l-amino-2,4-diazapenta-l,3-dienes 1186. Deprotonation of 1186 by the use of strong organic bases yields the corresponding 4//-imidazoles 1187 or imidazoles 1188 after amine elimination through an anionic 1,5-electrocyclization reaction. For the cyclization to occur, the amino compound 1185 needs to possess electron-withdrawing substituents such as alkoxycarbonyl or fluorenyl groups (Scheme 290) <2004EJO2567>. 

Amides of trifluoromethanesulfonic acid (triflamides) can be prepared by the reaction of the corresponding amines with triflic anhydride The most applicable in organic synthesis are iV-phenyltriflamides, which can be used as mild and selective Inflating reagents [110, lll ... 

Mercury(II) trifluoromethanesulfonate-N,N-Dimethylaniline (1). The reagent is prepared by reaction of triflic anhydride with yellow HgO in nitromethane with stirring for 18 hours. Then the amine is added, and a clear pale yellow solution is formed. 

---