Reaction between alkyl isocyanides and dialkyl acetylenedicarboxylates in the presence of benzoyl cyanides: one-pot synthesis of highly functionalized iminolactones

The highly reactive 1:1 adduct, produced from the reaction between dialkyl acetylenedicarboxylates and alkyl isocyanides, was trapped by benzoyl cyanide derivatives to afford dialkyl 5-alkylimino-2-cyano-2-aryl-2,5-dihydro-3,4-furandicarboxylates in fairly good yields.