Regioselective Synthesis of 3-Aminoimidazo[1,2-a]pyrimidines with Triflic Anhydride

The regioselective synthesis of 3-aminoimidazo[1,2-a]pyrimidines via triflic anhydride mediated amide activation and intramolecular cyclisation is reported. The nature of the added pyridine base allows access to both regioisomers from a simple common precursor. The method tolerates a range of functional groups and provides access to novel heterocyclic scaffolds.