Concise synthesis of Obovatol: Chemoselective ortho-bromination of phenol and survey of Cu-catalyzed diaryl ether couplings

Abstract

Concise total synthesis of obovatol (1) was achieved from the commercially available eugenol (5) via linear 4 steps in 40% overall yield. The key features of the synthesis involve the chemoselective orthobromination of phenol in the presence of isolated double bond and the efficient Cu-catalyzed Ullmann coupling of two aromatic moieties for the diaryl ether skeleton.