Synthesis of isocoumarin, 1‐isoquinolone and 4(1H)‐quinolone derivatives via seleno‐intermediates

The reaction of 2‐styrylbenzoic acids 2 with N ‐phenylselenosuccinimide (N‐PSS) affords 3‐phenyl‐iso‐coumarin derivatives 3 and 3,4‐dihydro‐3‐phenyl‐4‐(phenylseleno)isocoumarins 4 via selenolactonization. The reaction of 2‐styrylbenzamides 5 and 1‐(2‐aminophenyl)‐3‐phenyl‐2‐peropen‐1‐one derivatives 11 with N‐PSS also resulted in the formation of 1‐isoquinolone 6 and 4(1 H )‐quinolone derivatives 12 , respectively.