Total Synthesis of Debromoflustramines B and E Based on the Intramolecular Carbamoylketene–Alkene [2 + 2] Cycloaddition

Abstract

Total synthesis of debromoflustramines B and E has been accomplished by using a platinum-catalyzed addition reaction of o-aminophenylboronic acid with the allene and an intramolecular carbamoylketene-alkene [2 + 2] cycloaddition for the construction of the basic carbon framework of the target alkaloids as the key steps.