Stereoselective Synthesis of 2,6‐Disubstituted Piperidines Using the Iridium‐Catalyzed Allylic Cyclization as Configurational Switch: Asymmetric Total Synthesis of (+)‐241 D and Related Piperidine Alkaloids

Pressing the configurational switch: Use of enantiomeric Ir catalysts allows the vinylpiperidine building blocks 2 a and 2 b to be synthesized with high selectivity. Total syntheses of the dendrobate alkaloid (+)-241 D, its C6-epimer, and a spruce alkaloid are presented as applications.