Regioselective total synthesis of edulane and its angular analogue

Abstract

Herein we describe a 10-step total synthesis of edulane 3 and its angular analogue 18 from phloroglucinol. The key step involves ZnCl2-catalysed condensation of the appropriately substituted 2H-chromenes 8, 9 and 10 with the 2-alkoxy-1,4-benzoquinones 11 and 12, respectively.