ChemInform Abstract: Reactivity of Imines Towards 3-Trifloxypropeniminium and Propyniminium Triflates

The imines 5 and 11 react with 3-trifloxypropeniminium triflates 1a–d to afford the heterocyclic iminium salts 8, 9, 13, 15, and 17, respectively, or the propeniminium salt 21. Propyniminium triflates 22, 24 react with imines by initial conjugated addition, followed by a reaction sequence analogous to the one observed for the reactions of 1a–d with imines. Thus, salt 22 and aldimine 5b yield the propeniminium salt 21, while 24 reacts with tri-tert-butylazete 25 to afford the semicyclic vinamidinium salt 28. A crystal structure analysis of 28 is performed.