Total Synthesis of Diterpenoid Steenkrotin A1. Issue 23 (17th April 2015)

• Record Type: Journal Article
• Authors: Pan, Saiyong; Xuan, Jun; Gao, Beiling; Zhu, An; Ding, Hanfeng
• Is Part Of: Angewandte Chemie international edition. Volume 54:Issue 23(2015)
• Page Start: 6905
• Page End: 6908
• Publication Date: 2015-04-17
• Subjects: aldol reaction -- carbenoids -- natural products -- radical reactions -- total synthesis; Chemistry -- Periodicals; 540
• DOI: 10.1002/anie.201502034
• Languages: English
• ISSNs: 1433-7851

Abstract

Abstract: A concise and diastereoselective total synthesis of the diterpenoid (±)‐steenkrotin A is described for the first time. The strategy mainly features three key ring formations: 1) a rhodium‐catalyzed OH bond insertion followed by an intramolecular carbonyl‐ene reaction to build up the tetrahydrofuran subunit; 2) sequential SmI2 ‐mediated Ueno–Stork and ketyl–olefin cyclizations to construct the [5, 7] spirobicyclic skeleton; and 3) an intramolecular aldol condensation/vinylogous retro‐aldol/aldol sequence to form the final six‐membered ring with inversion of the relative configuration at the C7 position. Abstract : Work of steen : A concise and diastereoselective total synthesis of the diterpenoid (±)‐steenkrotin A is reported for the first time. The key features of the strategy are based on a rhodium‐catalyzed OH bond insertion, an intramolecular carbonyl‐ene reaction, sequential SmI2 ‐mediated Ueno–Stork and ketyl–olefin cyclizations, and a cascade intramolecular aldol condensation/vinylogous retro‐aldol/aldol process.