Total Synthesis of (+)-Superstolide A

A convergent and highly stereocontrolled total synthesis of the cytotoxic macrolide (+)-superstolide A is described. Key features of this synthesis include the use of bimetallic linchpin <b>36b</b> for uniting the C(1)−C(15) (<b>43</b>) and the C(20)−C(27) (<b>38</b>) fragments of the natural product, a late-stage Suzuki macrocyclization of <b>49</b>, and a highly diastereoselective transannular Diels−Alder reaction of macrocyclic octaene <b>4</b>. In contrast, the intramolecular Diels−Alder reaction of pentaenal <b>5</b> provided the desired cycloadduct with lower stereoselectivity (6:1:1).