Abstrait

An improved total synthesis of (-)-Hyrtiosal from (-)-Sclareol

Jing Wang, Xi-Bo Chen, Si-Kai Hua, Qian-Jia Yuan, Jiangmeng Ren, Bu-Bing Zeng

An efficient total synthesis of (-)-hyrtiosal was accomplished in linear 10 steps from commercially available (-)-sclareol. An acid-catalyzed cyclization of , -unsaturated amide successfully constructed the key intermediateWeinreb amide 4bwith bulkyN,O-dimethylhydroxylamine group, which benefited the stereoselectivity in the epoxidation of 5. One-pot reaction involved the rearrangement of epoxide 5 and the thiol protection of aldehyde 6 catalyzed by BF3Et2O was developed to give a 74% yield. This practical synthetic route provided (-)-hyrtiosal on grams scale.