One-pot synthesis of isoquinoline-5,8-dione derivatives from acylquinones and enamines

A new and facile method for the preparation of isoquinolinequinone derivatives has been developed. Treatment of 2-acyl-1,4-naphthoquinones or 2-acyl-5,6-dimethyl-1,4-benzoquinones with enamines (or imines), followed by addition of aqueous NH3 in MeOH afforded benz[g]isoquinoline-5,10-dione or isoquinoline-5,8-dione derivatives, respectively, in moderate to good yields.