Enantioselective sequential conjugate addition-allylation reactions: a concise total synthesis of (+)-podophyllotoxin.

A highly flexible and concise total synthesis of (+)-podophyllotoxin featured with an enantioselective sequential conjugate addition-allylation reaction was reported. Starting from commercially available 3,4,5-trimethoxycinnamic acid, this new route leads to (+)-podophyllotoxin 1 in only eight steps with 29% overall yield.