Cascade Multiple Diels–Alder Reactions of Styrene Derivatives with Maleimide or Maleic Anhydride

We developed novel one-pot multiple
Diels–Alder reactions,
which are frequently used in the construction of six-membered rings
in functional molecular synthesis. We report triple and double Diels–Alder
reactions with styrene derivatives, where the secondary Diels–Alder
reaction takes place at a different position from that of the conventional
Wagner-Jauregg reaction.