Transition-metal-free synthesis of 4-aminoisoquinolin-1(2H)-ones via a tandem reactionof arynes and oxazoles

A facile and transition-metal-free method for the synthesis of 4-amino isoquinolin-1(2H)-ones has beendeveloped. Arynes react with 4,5-disubstituted oxazoles through a tandem Diels–Alder reaction/dehydrogenation–aromatization/tautamerization process to produce 4-amino isoquinolin-1(2H)-ones in moderate to excellent yields. The reaction can be easily scaled up and the product can be transformed to isoquinoline derivatives efficiently.