A General Strategy for the Construction of Calyciphylline A type Alkaloids: Divergent Total Syntheses of (–)‐Daphenylline and (–)‐Himalensine A

An efficient general strategy for the synthesis of the Daphniphyllum alkaloids via the rapid construction of the common  core intermediate has been estabilshed, based on which a divergent total synthesis of (-)-daphenylline and (-)-himalensine A has respectively been accomplished in 16 and 19 steps. The present work features an enantioselective Mg(ClO 4 ) 2 -catalyzed intramolecular amidocyclization to construct the aza-bridged core structure; a Cu-catalyzed intramolecular cyclopropanation and subsequent phosphine-catalyzed Cope-type rearrangement to furnish the himalensine A scaffold; and a one-pot Diels-Alder/aromatization method to assemble the aromatic skeleton of daphenylline.