Microwave-Assisted aza-Friedel–CraftsArylation of N-Acyliminium Ions: ExpedientAccess to 4-Aryl 34-Dihydroquinazolinones

摘要

A one-pot microwave-assisted aza-Friedel–Crafts arylation of N-acyliminium ions, generated in situ from o-formyl carbamates and different amines, is reported. This metal-free protocol provides rapid access to diverse 4-aryl 3,4-dihydroquinazolinones in excellent yield without any aqueous workup. A solvent-directed process for the selective aza-Friedel–Crafts arylation of electron-rich aryl/heteroaryl/butenyl-tethered N-acyliminium ions is also described.