Synthesis of the C22−C26 Tetrahydropyran Segment of Phorboxazole by a Stereoselective Prins Cyclization

2000-04-12T00:00:00Z (GMT) by Scott D. Rychnovsky Christian R. Thomas
Tetrahydropyran rings are found in many complex natural products, and the segment-coupling Prins cyclization is an effective strategy for their synthesis. We report a four-step, stereoselective synthesis of the C20−C27 tetrahydropyran segment of phorboxazole. The key step is a Prins cyclization induced by catalytic BF3·OEt2.