Ring-construction/stereoselective functionalization cascade: total synthesis of pachastrissamine (jaspine B) through palladium-catalyzed bis-cyclization of bromoallenes.

Palladium(0)-catalyzed cyclization of bromoallenes bearing hydroxyl and benzamide groups as internal nucleophiles stereoselectively provides functionalized tetrahydrofuran. With this bis-cyclization as the key step, a short total synthesis of pachastrissamine, a biologically active marine natural product, was achieved.