Total Synthesis of (±)-Pestalachloride C and (±)-Pestalachloride D through a Biomimetic Knoevenagel/Hetero-Diels–Alder Cascade

A concise total synthesis of (±)-pestalachloride C and (±)-pestalachloride D was achieved through a Knoevenagel/hetero-Diels–Alder cascade reaction to test the nonenzymatic biosynthetic hypothesis of Shao, Wang, and co-workers. The cascade reaction generates a mixture of racemic indano­[2,1-c]­chromans like those found in the natural products.