Asymmetric Formal Synthesis of (-)-Swainsonine by a Highly Regioselective and Diastereoselective Allylic Amination Using Chlorosulfonyl Isocyanate

A concise asymmetric formal synthesis of (–)‐swainsonine from readily available D‐erythronolactone is described. The key steps include a highly diastereoselective amination of a chiral benzylic ether, which occurs with the retention of stereochemistry using chlorosulfonyl isocyanate, and a palladium‐catalyzed decarboxylative N‐allylation of an allyl carbamate. A concise asymmetric formal synthesis of (–)‐swainsonine from readily available D‐erythronolactone is described. The key steps include a highly diastereoselective amination of a chiral benzylic ether, which occurs with the retention of stereochemistry using chlorosulfonyl isocyanate, and a palladium‐catalyzed decarboxylative N‐allylation of an allyl carbamate.