Electrophilic hexa(methoxycarbonyl)cycloheptatrienyl anion in the synthesis of electron-deficient 5-hydroxyisoquinolones

The reaction of hexa(methoxycarbonyl)cycloheptatrienyl anion with amines affords 5-hydroxyisoquinolones bearing four 4,6,7,8-positioned methoxycarbonyl groups and having unsubstituted C³H unit. The reaction is selective due to better steric availability and both charge and orbital distribution within the seven-membered ring and may proceed through a nucleophilic attack on the allyl-anionic moiety.