Divergent Asymmetric Syntheses of Podophyllotoxin and Related Family Members via Stereoselective Reductive Ni-Catalysis.

A nickel-catalyzed reductive cascade approach to the efficient construction of diastereodivergent cores embedded in podophyllum lignans is developed for the first time. Their gram-scale access paved the way for unified syntheses of naturally occurring podophyllotoxin and other members.