4-Arylphthalaz-1-ones (2a–e) are prepared by the hitherto unknown reaction of N- aminophthalimide (1) with aromatic hydrocarbons under Friedel-Crafts conditions. The reaction of N-aminophthalimide with Grignard reagents presents another convenient method for the synthesis of 4-alkyl or 4-arylphthalaz-1-ones.
