Synthetic Efforts toward the Isoindolinone Core of Muironolide A

Abstract

Studies directed toward the isoindolinone core of muironolide A are described. An initial plan to implement an intramolecular Diels-Alder cycloaddition was thwarted by an undesired conjugate addition during the attempted preparation of the DielsAlder substrate. A revised retrosynthetic analysis revealed a direct, albeit challenging, intermolecular Diels-Alder disconnection. Toward this end, a sterically hindered and electronically deactivated diene was utilized with N-phenylmaleimide to achieve a DielsAlder cycloaddition.