Synthesis of Novel Benzo[6,7][1,4]oxazepino[4,5-a]quinazolinone Derivatives via Transition-Metal-Free Intramolecular Hydroamination

Novel benzo[6,7][1,4]oxazepino[4,5- a ]quinazolinone derivatives were synthesized through an efficient 7- exo - dig hydroamination of 3-substituted-2-[2-(prop-2-yn-1-yloxy)phenyl]-2,3-dihydroquinazolin-4(1 H )-ones in the presence of potassium tert -butoxide (KO t -Bu) in DMF at 130 °C.