Studies towards the total synthesis of palauʹamine. Formation of 4,5-dihydropyrrole-2-carboxylate intermediates by alkene–enamide ring-closing metathesis

A highly functionalized 4,5-dihydropyrrole-2-carboxylate is assembled by alkene–enamide ring-closing metathesis. Subsequent intramolecular azomethine imine dipolar cycloaddition provides a triazacyclopenta[cd]pentalene intermediate of potential use in a total synthesis of palauʹamine.