Addition of isocyanides to ?-(methylthio)-benzylidenamidinium iodides: A surprising access to 2-(dialkylamino)imidazoles and 3,5-diamino-2H-pyrrolium salts

Four-membered rings from isocyanides: Developments since the mid 1980s

“…But a competing reaction gave the 2-aminoimidazoles 22a-e (by involvement of the HC=NR' 2 moiety of 20). 16 …”

Studies on the interaction of isocyanides with imines: reaction scope and mechanistic variations

“…However, the direct reaction of imines and isocyanides has been considerably less studied and, in the absence of a carboxylate, the mechanistic outcome is considerably modified [ 2 ]. A relevant precedent was described by Deyrup in the late sixties, demonstrating the double incorporation of an isocyanide moiety to an imine [ 3 – 4 ]. Interestingly, the 3CR between a carbonyl, an amine and an isocyanide, taking place through the intermediacy of the in situ generated imine, leads to α-aminoamidines, resulting from the trapping of the nitrilium cation by the remaining amine [ 5 – 8 ].…”